Proceedings of the Subcommittee on
Veterans Affairs
Issue No. 15 - Evidence - May 9, 2018
OTTAWA, Wednesday, May 9, 2018
The Subcommittee on Veterans Affairs met this day at 12:05 p.m., to continue its study on the services and benefits provided to members of the Canadian Forces; to veterans; to members and former members of the Royal Canadian Mounted Police and their families (Topic: Study on Cannabis Use for Medical Purposes by Canadian Veterans).
Senator Jean-Guy Dagenais (Chair) in the chair.
[Translation]
The Chair: Honourable senators, welcome to the Subcommittee on Veterans Affairs. Before we begin, I will ask my colleagues to kindly introduce themselves, starting on my right.
[English]
Senator Wallin: Senator Pamela Wallin from Saskatchewan.
Senator McIntyre: Senator Paul McIntyre from New Brunswick.
Senator Richards: Senator David Richards from New Brunswick.
Senator Griffin: Senator Diane Griffin from Prince Edward Island.
Senator Jaffer: Senator Mobina Jaffer from British Columbia.
[Translation]
The Chair: I am Jean-Guy Dagenais from Quebec, chair of the subcommittee.
Thank you to my colleagues. Today we are continuing our study on the use of cannabis for medical purposes by Canadian veterans. Our witnesses are Mr. Zachary Walsh, associate professor, Department of Psychology, University of British Columbia, and Mr. David Pedlar, Scientific Director, Canadian Institute for Military and Veteran Health Research. He is accompanied by Dr. J. D. Richardson, consultant psychiatrist, physician clinical lead, at the Parkwood Operational Stress Injury Clinic.
Welcome, gentlemen. We will begin with Mr. Walsh’s presentation.
[English]
Zachary Walsh, Associate Professor, Department of Psychology, University of British Columbia, as an individual: Good afternoon, honourable senators. Thank you for inviting me to present. It is a privilege.
I am a researcher in cannabis and mental health and a tenured psychology professor at the University of British Columbia. I have studied issues related to the use of substances including alcohol, tobacco and illicit drugs. My focus for the past several years has been on cannabis use, both medical and nonmedical, and its effects on mental health.
I am currently funded by the Canadian Institutes of Health Research and the Social Sciences and Humanities Research Council of Canada to examine the consequences of cannabis use and cannabis legalization on the health and well-being of adults. My past work has included some of the largest surveys of medical cannabis users in Canada and an extensive review of the impact of medical cannabis use on mental health. I also lead an ongoing randomized control trial of cannabis for PTSD, which, together with a parallel study in the U.S., are among the first to evaluate this treatment.
As a clinical psychologist, I have had diverse opportunities to work with individuals who struggle with the aftermath of trauma. I received training within the Veterans Affairs hospital system in the U.S. and now provide clinical supervision to graduate student trainees in the assessment of PTSD. My testimony today will draw primarily on my own research and knowledge of the empirical literature on cannabis and PTSD but will also be informed by my first-hand experiences working with individuals who use cannabis to treat PTSD.
[Translation]
The Chair: Mr. Walsh, could you please slow down. That will make it easier for our interpreters.
[English]
Mr. Walsh: Today I would like to focus on the use of cannabis for PTSD and for co-occurring conditions prominent among veterans, as well as providing some thoughts on the potential impacts on veterans of the imminent legalization of nonmedical cannabis use.
It is sometimes noted that the evidence for the effectiveness of cannabis for PTSD is not strong. This usually refers to the lack of randomized controlled trials, RCTs, testing cannabis for PTSD. Such trials would certainly add to our confidence in how best to use or not use cannabis for PTSD, which is why we are currently undertaking trials of this sort. However, despite the lack of RCT evidence, it is nonetheless my opinion there is good reason to be hopeful regarding the potential for cannabis medicines to help improve the lives of individuals with PTSD.
Human studies that are not RCTs deserve attention. For example, studies show differences in the naturally occurring cannabis systems — the endocannabinoid system of individuals with PTSD, suggesting that dysfunction in this system may explain high rates of cannabis use among PTSD patients.
It is essential that we follow the leads provided by patient behaviours, particularly in areas where other evidence may be lacking. Surveys of medical cannabis users identify high levels of use to treat PTSD, and a retrospective study of medical cannabis patients in the U.S. reported substantial reductions in PTSD symptoms after uptake of medical cannabis use.
These studies highlight cannabis use to help with sleep and to cope with anxiety and depression that are part of PTSD.
Sleep disturbance often emerges as among the most debilitating PTSD symptoms, and one which is most responsive to cannabis therapy. Restorative sleep is key to health and well-being and, when it is disrupted, other aspects of health rapidly deteriorate.
I have spoken with many individuals who use cannabis for PTSD who report going from sleeping in brief stretches, interrupted by terrible nightmares, to having their first full night’s sleep in years after initiating cannabis therapies. Clinical research also supports the benefits of cannabis in PTSD-related sleep disturbance. Synthetic cannabinoids have demonstrated good effects in reducing nightmares and improving sleep among PTSD patients.
Our experience in Canada over the past few years also speaks to the therapeutic potential of cannabis for PTSD. Although the dramatic increase in enrolment by veterans in the ACMPR has caused concern in some quarters, it is what we might expect to see from the introduction of an effective but unconventional treatment for a difficult condition. Slow and steady increases at first until a tipping point caused by positive word of mouth leads to exponential growth.
Patient-reported self-efficacy and treatment uptake are not the accepted gold standard for determining the effectiveness of a medication. However, the devastating consequences of untreated PTSD and the inadequacies of existing treatments for many sufferers make it essential that all promising avenues be explored. Cannabis should be compared to existing options, not a hypothetical gold standard.
The quantities of cannabis being used by some veterans may appear excessive but perhaps no more so than the long lists of prescription medications often used to address PTSD and co-occurring conditions. For many, the side effects of cannabis are well tolerated compared to those of the antidepressants, sedatives and other medications that confer side effects such as weight gain, sexual dysfunction and lethargy that dramatically decrease quality of life. In contrast, even at high doses, cannabis can be a relatively gentle medicine with low toxicity.
Perhaps the greatest concern is the development of cannabis dependence. However, effective use of a medication to treat symptoms of a chronic condition cannot be considered disordered, and the cannabis withdrawal symptom is short-lived and relatively mild compared to those of some other widely used prescription medications.
One benefit of cannabis therapies is the potential to treat co-occurring conditions and replace several medications. Specifically, a recent comprehensive review from the National Academies of Sciences, Engineering and Medicine concluded that cannabis was effective for treating chronic pain in adults, which is particularly important given the high rates of opioid use disorder among individuals with PTSD. Indeed, growing evidence indicates that cannabis is increasingly being used as an opioid substitute that may reduce fatal opioid overdose.
Recent reporting from The Globe and Mail just this week that focused specifically on Canadian veterans supports the conclusion that cannabis may be being used instead of, rather than in addition to, other medications.
Research from our group found that cannabis not only reduced pain but helped patients to be more active despite chronic pain. Given the negative effects of the isolation that plagues too many veterans with chronic pain and PTSD, the potential of cannabis to facilitate activity and social integration is important.
Our review of medical cannabis and mental health found that medical cannabis patients overwhelmingly report using cannabis to reduce anxiety and depression in addition to a primary complaint of pain. The potential of cannabis to address both pain and anxiety is particularly important in the context of PTSD given the potential lethality of combining benzodiazepine sedatives and opioid pain killers, both of which are widely used by veterans.
Cannabis also has the potential to substitute for alcohol, and the calming effects of cannabis use may protect against domestic violence, which is also a heightened risk to the well-being of concerns.
With regard to the impact on veterans of imminent cannabis legalization, I believe the public health approach put forward by the current government will have a positive effect on the lives of veterans and should not be delayed.
Our research identifies fear of negative judgment as an impediment to open communication with caregivers regarding cannabis use. Veterans with mental health conditions who use cannabis bear the burden of a double stigma that could be a substantial barrier to accessing proper medical care and engaging in frank conversation with providers. To the extent that legalization reduces stigma, it will have a positive effect on the health of veterans.
Legalization will also have a positive effect by fostering research into the development of best practices for the therapeutic use of cannabis.
One concern I have regarding legalization as currently planned involves per se limits for driving. Veterans who use cannabis therapeutically may consistently exceed the proposed nanogram limit irrespective of acute cannabis intoxication. No one should be impaired on the roads, but veterans who use their medication responsibly should not be forced to abandon driving entirely.
Thank you very much.
[Translation]
The Chair: Thank you very much for your presentation, Mr. Walsh. We will now move on to Mr. David Pedlar.
[English]
David Pedlar, Scientific Director, Canadian Institute for Military and Veteran Health Research: Thank you for the opportunity to address members of the Senate and this committee on this important topic.
My name is David Pedlar. I am a full professor in the School of Rehabilitation Therapy at Queen’s University and scientific director of the Canadian Institute for Military and Veteran Health Research. We link together 43 Canadian universities as a network, 10 global affiliates and industry partners to offer an independent, arm’s length perspective to understand and help solve the health issues facing Canadian Armed Forces personnel, veterans and their families. Over 1,700 researchers have contributed to our mission. CIMVHR is a thriving community that engages researchers, practitioners, government and interested parties. We are all about working together to solve these problems.
First, my heart goes out to the veterans in Canada that have turned to medicinal cannabis as an alternative treatment. I know many of them personally, and I have also met many U.S. Armed Forces 9/11 veterans when I lived in Los Angeles in 2016 as a Fulbright Visiting Research Chair in Military Health at the University of California. They all have similar stories: physical and mental health issues that they attributed to military service; common mental health issues like PTSD and depression, as well as chronic pain arising from physical trauma or wear and tear with the rigours of military service. I note that military health problems commonly occur with physical health problems and chronic pain, and these can impair functioning. For example, a common complaint that I saw was that because of their mental and physical health conditions, they had challenges fulfilling roles in life. Many of the veterans I have known agonized over things like how their health prevented them from being the parents and spouses that they wanted to be.
Typically, their journey to feel better started with traditional treatments. They climbed the medication ladder, trying a wide range of prescribed antidepressants, anti-anxiety medications and a wide range of other traditional and nontraditional treatments and therapies, but they were not satisfied with the results. Finally, they turned to cannabis as an option in seeking relief. Some I have met claim that cannabis has helped them greatly, and some have experienced adverse side effects and discontinued use.
Regarding policy on medicinal cannabis under discussion here, one important lesson is the importance of adhering to the principles of evidence-based policy and decision-making, especially when we will publicly fund health care treatments. The government policy under discussion is an example, perhaps, of doing it backwards. The initial policy on veterans’ cannabis was not based on high-quality scientific evidence of safety and effectiveness. Therefore, the challenge facing government over the past year or two has been how to introduce rationality to a policy that was not initially evidence-based. However, here we are, so it is essential to balance compassion with caution, recognizing that many veterans are already using cannabis and could be adversely affected by dramatic policy changes.
CIMVHR proposes two priorities. First, from our perspective, is the investment in new research in the safety, effectiveness and cost effectiveness of medicinal cannabis. Overall, the quality of research evidence on safety and effectiveness of medicinal cannabis is of low quality. There is encouraging evidence that something in cannabis has good therapeutic value. On the other hand, cannabis can be addictive and has a variety of other adverse effects. It is an extremely complex mix of chemicals, has complex pharmacokinetics and pharmacodynamics and has positive and negative acute and chronic effects that are not well understood. THC concentrations in cannabis have increased over time, and overdose can occur. In addition to overdose, motor impairment is a consequence of use and can lead to motor vehicle and other kinds of accidents.
High-quality research is needed. The overall goal is to improve the quality of evidence for safety and effectiveness of medicinal cannabis. One key line of research would focus on safety and effectiveness, looking at how cannabis affects the body’s endocannabinoid system. We should also focus on it like any other drug, recognizing that virtually all medications have an on-target therapeutic effect and off-target side effects. Another key line of research would focus on cannabis from a public health perspective — the impact on physical and mental health, but all domains of functioning: at home, at work and in the community. How does it really impact veteran well-being?
The second priority is that CIMVHR has an important role to play in knowledge dissemination, which is very important. Veterans desperately need more information on both the potential benefits and adverse effects of using cannabis for medical purposes. There is an enormous amount of misinformation in marketing out there, making the need for quality, authoritative information even greater. This will become even more critical once cannabis is available for recreational use.
Health professionals would also benefit from additional information. CIMVHR can play a key role in collaborating on this with provincial and national medical associations. More effective collaboration could also be made with a network of Veterans’ Affairs-funded OSI clinics and those who authorize the use of medicinal cannabis. CIMVHR is well-situated to bridge those gaps.
In closing, I want to mention that CIMVHR is currently building a partnership with the DeGroote Centre for Medicinal Cannabis at McMaster University and Parkwood OSI Clinic to support research and knowledge dissemination into medical cannabis in the veteran space. I would highly recommend that you invite the DeGroote Centre team from McMaster here to speak. That would be James MacKillop, Jason Busse and Ramesh Zacharias, with whom we have been working lately and hope to play a leadership role in this area moving forward. Thank you.
[Translation]
The Chair: Thank you very much, Mr. Pedlar. Dr. Richardson, will you be giving a presentation?
[English]
Dr. J.D. Richardson, Consultant Psychiatrist, Physician Clinical Lead, Parkwood Operational Stress Injury Clinic, Canadian Institute for Military and Veteran Health Research: Yes, I do. I would like to thank the Senate committee for the opportunity to address on this important topic of cannabis for medical purposes in veterans.
I am a consultant psychiatrist and Physician Clinical Lead at the Parkwood Operational Stress Injury Clinic. I am also a fellow with the Canadian Institute of Military and Veteran Health Research, CIMVHR, and Associate Professor at Western University. Over the past 20 years, my clinical and research work has focused primarily on veterans and Canadian Forces members with PTSD and other operational stress injuries.
I will keep my introductory remarks short, as Dr. David Pedlar has already highlighted the issues of cannabis use for medical purposes, especially regarding both the short- and long-term safety and effectiveness of cannabis for medical purposes.
I support CIMVHR’s priorities of both research and knowledge dissemination. High-quality research for cannabis for medical purposes is lacking, and there is a desperate need for good clinical research involving not only the veterans but also their families. This research should examine not only symptom reduction but also the quality of life of the veteran and their families.
We look forward to collaborating with CIMVHR and McMaster’s Michael G. DeGroote Centre for Medicinal Cannabis on their research agenda. This type of research is extremely important, as military-related PTSD does not respond as well to either medication treatment, pharmacotherapy or psychotherapy — talking therapy — when compared to civilian PTSD.
As was already reviewed, accurate information to veterans and their families, and to community care providers, is crucially needed. With this knowledge, veterans and their care providers can make more informed decisions on the potential benefits and adverse effects of using cannabis for medical purposes.
Thank you.
[Translation]
The Chair: Thank you very much, Dr. Richardson. We will begin the question period. I invite Senator Jaffer to ask the first question.
Senator Jaffer: Thank you for being here today.
[English]
First, I have a question about the amount of cannabis that is now being provided. I think it is 3 nanograms a day, and I understand that some want more. Are any of you able to comment on that? Some need more; let me put it that way.
Mr. Walsh: With the research being conducted now, we are trying to determine an ideal dose. We can see from naturalistic observation of what is going on with medical cannabis patients broadly and veterans with PTSD specifically that it seems that would be sufficient for most but not all to the extent that there are some who report using higher doses effectively and that lesser doses are not effective. In the absence of clinical trials to specify dose, the reports of patients are our best guidance.
Among recreational users, very few use more than a few grams a day, and most use less. If the use is recreational, it is rare to see it at those higher levels. My interpretation is that those higher levels likely represent medical need, because they are not consistent with recreational use in general.
Senator Jaffer: Thank you for that.
You know that our committee is another voice for veterans. We are trying to find out how we can support veterans and improve the lives of veterans who have given such great sacrifices for our country. We owe them a lot. I would like to ask you what you think the barriers are. You covered some of them, but could you put it down as one, two, three? What are the barriers for accessing medical cannabis? You covered it, but I would like it in point form again.
Mr. Walsh: One of the big barriers we have come across in our research with medical cannabis more broadly is stigma and caregiver communications. People are concerned that their cannabis use will be perceived in a manner that is stigmatized such that they are reluctant to discuss it with their caregivers. Then they are left on their own or left to work outside of the authorized medical community to determine how best to use cannabis. In many cases, they work with ad hoc providers or dispensaries to gather the best information. However, as my colleagues noted, authoritative information can be hard to come by, and there is such diversity of opinion that it can be quite a struggle for a medical cannabis user to figure out the best dose and best type.
As my colleagues also noted, there are a number of different potential active ingredients in herbal cannabis. With regard to your comment about the high doses, it could be that some patients are looking for cannabinoids or finding certain cannabinoids effective that are present in only small doses in cannabis. That might explain why they use larger doses. But more research is needed to determine that.
Senator Jaffer: Also, when you are purchasing on your own, there are all kinds of differences and exact doses in the different cookies or whatever people are purchasing.
I was hoping you would talk about stigma, because I wanted to know if that is a barrier. With legalization, will that make a difference for veterans? Will it make it more open to access for medicinal purposes?
Dr. Richardson: I would like to address one of the earlier questions. One of the challenges in the medical profession that has an implication for veterans who are seeking to obtain cannabis for medical purposes is the lack of evidence we look for in terms of medical treatment in order to be able to provide or authorize this type of treatment. That area is extremely lacking.
There are also the challenges for a lot of veterans accessing primary care and specialty treatment, as you are probably aware. Are veterans aware that there are effective treatments for PTSD and depression that are already out there, and how do they access it? It is a complex picture.
Mr. Pedlar: If I may talk about the 3 gram or 10 gram thing, I don’t think there is any clear scientific basis for either. It would be based on an input from practitioners, but there is no clear scientific basis. In a sense, I would call those arbitrary. We know, however, that higher use is associated with higher risk, including addiction. I think both 3 grams and 10 grams would be considered high, although there may be individual circumstances where they could be warranted. I think 10 grams would be considered extremely high, but if people are on 10 grams, there are issues around withdrawal and other hardships that might be important issues in terms of how you would transition from 10 grams to 3 grams.
Senator Jaffer: Are there gender differences?
Dr. Richardson: That is a good question, and I’m not sure there are any studies out there. However, for most medications that are approved, the ones with a drug identifying number, most of the research is done on men. There is a definite lack of evidence and research that is gender-specific. That is a good point to raise as we start doing research on this, because it could be quite different. We do know that the impact of alcohol on women is significantly different than for men, but we do not know about that in terms of cannabis, as far as I am aware.
Mr. Walsh: I think there may also be gender differences related to the stigma issues that you raised, where there may be a particular stigma among women for using cannabis, particularly as it relates to parenting issues. Some research from our group has shown particular attitudes toward parenting and cannabis that might add an additional barrier to trying to access that cannabis medication.
To add to the stigma issue, our research with medical cannabis patients — and this is a few years old so I think that it’s a fast-moving target — the stigma also extends to physicians who are reluctant to go against some of the provincial regulatory bodies and be perceived as endorsing a medication that doesn’t have the kind of support they might want. What we’ve come across, anecdotally at least, is physicians recommending it but also being reluctant to recommend it officially. Instead, they are recommending it casually or deferring it to the illegal market.
Senator Jaffer: It’s a real opportunity to have you here, Dr. Richardson, especially around PTSD. We as a committee have looked at this and have been preoccupied with it. Maybe not directly, all of us individually, with the horrible sad stories we hear. Do you think this will help? You did say that, but further, I would like you to expand on whether legalizing cannabis will make a difference for veterans suffering from PTSD.
Dr. Richardson: I think that’s a very interesting question, because it’s hard to know if legalizing would necessarily help individuals who have PTSD. Whether or not the evidence is there, for example, for Cesamet or nabilone, which is a medication that affects the endocannabinoid system in your brain, that has been demonstrated to decrease the frequency and severity of traumatic nightmares. We know there are other drugs that are legal and can help calm an individual, for example, alcohol. We know that when you drink, if you have social anxiety, it helps, but we don’t recommend it as a treatment. There are things that might be helpful in terms of symptoms, but it’s not necessarily treatment in the long term. I’m not convinced yet that the evidence is there for cannabis as a plant, but there is good, emerging evidence that there is something in this plant that has been around for a long time. In terms of the human brain, we have receptors for it where it has both good and bad impacts.
[Translation]
The Chair: Dr. Richardson, you have piqued my curiosity. Having worked in the insurance industry for some time, I am very familiar with the drug identification, or DIN, system. Did you not say that the system and the research are based on men only?
[English]
Dr. Richardson: I think that’s a very good question. A lot of the current drugs that are approved by the FDA are often studied initially on men, so this is the average 70 kilogram male, and there is a lack of research on the specific effects of drugs on women. Currently, if you try to get studies published or if you are trying to get new medication, my understanding is that you have to also look at the gender aspect. Does that help answer your question?
[Translation]
The Chair: Yes. Since my work related to medications, I am very familiar with the DIN system. Yet I did not know that the DIN was based on research conducted on men only, hence my surprise. Thank you for your answer.
[English]
Senator McIntyre: Gentlemen, thank you for sharing your knowledge with the subcommittee on the state of research and knowledge on the use of cannabis for medical purposes. Your presentation is very interesting.
This is the second meeting. At the first meeting, Veterans Affairs Canada appeared before us to explain its reimbursement policy for cannabis for medical purposes. Veterans Affairs Canada informed us, as I recall, that the maximum reimbursement limit of 3 grams per day is based on studies showing that the average Canadian who uses cannabis for medical purposes consumes less than 3 grams per day. In your opinion, do veterans’ physical and mental injuries require more or stronger medical cannabis compared with that used by the general population?
Dr. Richardson: I think that’s a very important question, and I don’t think we have an exact answer with regard to what is needed for a dose. Whether you’re smoking cannabis or using edibles will also affect the number of grams that is required.
The challenge, from my perspective as a specialist, is that we don’t see individuals who fully recover using cannabis because if you fully recover on something, you’re not seeing a specialist within our clinical system. It’s hard to know exactly whether 3 grams is ideal or fewer than 3 grams. As clinicians, we see individuals using lower doses of 1 to 2 grams to help them sleep, and they are reporting that it is helpful. For those on higher doses, we don’t have the evidence as to whether or not it’s been helpful. Some veterans are obviously reporting that the higher doses have been helpful, or it’s what they have needed.
Senator McIntyre: Do you have data on the amount of cannabis generally used to relieve some medical conditions, and if so, what are they?
Dr. Richardson: Not on hand. I do not have any of that specific data.
Senator McIntyre: Are cannabis producers involved in the studies on the effects of cannabis for medical purposes?
Mr. Walsh: The study that is ongoing, which I lead and is hosted by UBC, is sponsored by Tilray, a licensed producer of cannabis. Other licensed producers are also engaged in a variety of different research.
Senator McIntyre: Wouldn’t their involvement pose a risk of bias or conflict of interest?
Mr. Walsh: As is typical of pharmaceutical development, there is often an industry component. I don’t think cannabis is different from other medications where the pharmaceutical industry sponsors the trial.
Senator McIntyre: Any other comments on that?
Dr. Richardson: I think it introduces the potential for bias, but it doesn’t necessarily mean that there is a bias. In anything that would be published, if it’s supported, it will be indicated in the publication.
Senator McIntyre: How do you think the legalization of recreational marijuana will affect veterans’ use of medical marijuana?
Dr. Richardson: We don’t know. However, I would assume that, like most things, once it becomes legalized, there will be an increased use. Whether or not veterans might be using it for medical purposes to treat symptoms, they might also be using it, as a lot of Canadians are using it, for recreational purposes. Some might find it helpful and some might not find it helpful.
Senator McIntyre: I’ll rephrase the question: Do you anticipate that people could self-medicate using recreational cannabis without appropriate medical follow-up? If so, what would be the consequences of this phenomenon, in your opinion?
Dr. Richardson: As clinicians, our approach would be similar to alcohol. We know that many individuals will self-medicate with alcohol to help them sleep or to control if they are nervous or upset. I would assume that the approach will be very similar to legalized recreational cannabis. What is important is probably public education and information on safe use and the potential drawbacks of continuous use.
Mr. Walsh: I think that legalization, to the extent that it reduces stigma, will bring people who are currently self-medicating but perhaps concerned about disclosing that to their physician into closer communication with their physician. It will be something that is a little easier to speak to your doctor about once it’s generally legal.
Senator Wallin: I want to go over some of the similar turf that has been discussed here. Last week, in our first assessment of this, we were trying to get at the question of how VAC decided to go from 10 grams to 3 grams, and all of you seemed to indicate that we still don’t have good research on that. They cited one licensed producer who said that the average non-veteran patient uses 1.5 grams of medical marijuana compared to 4.6 for the veteran user. I don’t know how relevant those statistics are. They were cited, so you might want to comment on that.
When we’re talking about 3 grams versus 10, that’s a huge difference. Can any of you give us some indication of what state — and I know this varies with individuals — a person might be in emotionally or physically, their ability to function, if they are on 10 grams versus 3? I raise part of that because it comes back to your question about driving and engaging in other activities because this is a crucial point in the legalization of recreational marijuana. If we can look at it through the vet perspective, that may give us some insight on the other.
Mr. Pedlar: I’ll stay aside from setting 3 grams or 10 grams. Maybe there are general ideas that can provide guidance. One was that higher use is associated with higher risk. Therefore, I guess the thoughts would be caution and compassion. While I can’t say that 3 grams is better than 10 grams, you could say that given those issues, it could be scientifically justified that you might want to have a specialist engagement in having higher levels, however those are defined. At least around the parameters of reduction, there would be justification for doing so.
Senator Wallin: Is 3 grams too low for the reimbursement bar?
Mr. Pedlar: Because the levels are arbitrary, I can only give general direction on the decision. There is a justification for the direction of the decision. Most people would say 10 grams is a lot, and some people would say 3 grams is still pretty high compared to averages, and so they were stuck with this probably unenviable situation of trying to set limits when there is no clear foundation about how to set those limits. That would be a clear policy struggle that they faced, and that’s where that came up.
Dr. Richardson: Following the same line of compassion and also caution, it’s very hard to pinpoint a specific maximum dose. In general, when we’re prescribing a medication, whether it’s an antidepressant or a blood pressure medication, there is what we call a therapeutic window, which means there is a dose that within this range will work for the average individual for that condition. However, there are some individuals who, because of the way they are metabolizing the drug in their liver or the severity of their symptoms or the makeup of their brain, may require a higher dose, and there are some individuals who require a very small dose because they don’t metabolize medication or a drug well.
The challenge with cannabis is finding a specific gram because it’s a complicated drug from a plant as opposed to something that is quite specific with a mix. I think as Dr. Pedlar alluded to, with anything, as you go up, there will be a ceiling effect, meaning that you are no longer getting a potential benefit but you are getting a higher risk of developing side effects. That would be very common in terms of pharmacology. It’s always that balance: If we go beyond whatever the number is finally decided, you’re going to have more side effects, and do they outweigh the risk? That’s always a challenge. As was already discussed, hopefully the individual who is using would feel comfortable discussing it with their care provider so they can both get an informed decision.
Senator Wallin: It comes up for the reason — I said it before and I do want to hear you on that question — that if and when it is legalized, you will have people probably self-medicating and getting the 3 grams that’s funded but maybe buying other stuff on the black market or in a legal store that has a totally different composition and may have different kinds of ingredients in it. There is the impact of mixing and of self-medicating. To me, I’m not sure I want to be on a highway with somebody who has ingested, in some form or another, 10 grams of marijuana.
Mr. Walsh: Those are very good points. One thing that is important to consider with cannabis as a medicine is there is a substantial level of tolerance that develops, and cannabis is notable in the sense that tolerance comes and goes rapidly. You can develop tolerance quite quickly and you can lose that tolerance quickly as well. If veterans are using regular high levels of cannabis, the effects of 10 grams would be very different from a naive user or someone unused to cannabis using 10 grams a day.
In my experience, there is a great variety of styles of use, even amongst people using it for the same condition, for PTSD. One veteran may take a few puffs before bed to help suppress dreams, and that may take less than a gram or half a gram a day. Someone who is also suffering from chronic pain may want to feel the effects throughout the day and may require a higher dose. If that person is using it throughout the day to address chronic pain, they may develop a tolerance that requires greater doses to aid in sleep. Tolerance is a big issue, and 10 grams, or even 2 or 3 grams for an experienced user, can have the same effects as just a few puffs for someone who is naive. Reasons for use and tolerance can be big factors there.
The other thing about a daily limit is that it can vary from day to day. If someone is having a particularly bad day, they may use much more than on a relatively good day and may not want to be in a situation where they don’t want to use their week’s cannabis in one day if they are having a bad day. A 10 gram per day limit does not necessarily mean 10 grams every day. There is something called self-titrating that’s quite common with cannabis where people use to the point that they feel the effects they require to control their symptoms.
I hope that addresses some of that.
Senator Wallin: It affects the other debate we are all involved in on Bill C-45 and Bill C-46. Given the motor impairments that occur and the addictions, how do we decide if a medical marijuana user, a vet in particular, should not be denied the right to drive or participate in other activities? And I agree there are already enough punishments. How do we decide? What will we do? The police pull them over on the side of the road, and they say, “Yes, I’m impaired, but I’m a vet.” Realistically, how can we make this work?
Mr. Walsh: There are procedures in place for medications like antihistamines, benzodiazepines and opioids, all of which have a similar level of impairment to cannabis amongst medical use.
It’s also worth noting that research has shown that medical cannabis users perform better on tasks that require complex mental functioning when properly medicated rather than when they are suffering from their symptoms. It’s not relative to a perfect situation; rather, it’s relative to a situation where they may be impaired from their symptoms without their medication.
We have ways of dealing with impairment that comes from medications, and I think cannabis can fit within that framework. The level of impairment in driving, while substantial, is nothing like what we see with alcohol. I think we should be using analogies from other medications rather than analogies from alcohol when we consider road safety.
Senator Wallin: Do we actually know that?
Mr. Walsh: The best evidence suggests that cannabis impairment behind the wheel is more similar to things like antihistamines, benzodiazepines and opioids — perhaps less than benzodiazepines like Valium — than it is like alcohol.
Dr. Richardson: The challenges that might occur with cannabis at the higher doses are that it’s hard to be sure exactly what they are taking because there are multiple different brands and strains —
Senator Wallin: Especially if you mix.
Dr. Richardson: — which might be different than when you compare it to opiates or pain medication, antihistamines or benzodiazepines. If an individual says they are taking X amount of those, we know for the most part that is the number of grams and we can study the effect on the human body for that amount. It is more of a challenge when its cannabis, whether recreational or not.
Mr. Pedlar: I don’t have much to add, but I will say that if we are talking more generally than just veterans, we might be looking at more seniors who are veterans as well using cannabis for medicinal and recreational purposes. From the seniors’ point of view, because we are talking about multiple medications, we may also want to scope the issues of cannabis use in the context of polypharmacy as well. I wanted to add that to the discussion.
[Translation]
The Chair: Mr. Pedlar, I have a supplementary question for you. Once the bill is passed, might veterans be tempted to use their medical marijuana in combination with what is available on the illegal market? Would that not be dangerous?
[English]
Mr. Pedlar: I don’t feel I have enough background to answer that question well. I don’t know if my colleagues would be able to.
[Translation]
The Chair: Dr. Richardson or Mr. Walsh, do you not think that, once the bill is passed, it could be dangerous to combine two types of cannabis? A veteran might be tempted to add a few grams from the illegal market to the 3 grams to which they are entitled. Would it not be dangerous to use two different types of cannabis? They might not be the same.
[English]
Dr. Richardson: The potential is always there that if you are going to be mixing and increasing — if you’re normally taking 3 grams but then decide to take more and buy it on the streets, I would assume that can and should be studied. That might be occurring already, and that might be an area that warrants further study.
Mr. Walsh: One of the potential benefits we may see with legalization is that there will be more access to well-characterized cannabis so that if veterans are accessing outside of the program, they are able to know exactly what they are getting. Right now, as you say, if they are getting cannabis from the illicit market, it’s hard to know what is there. Legalization might reduce some of those risks associated with accessing illicit-market cannabis.
[Translation]
The Chair: That is assuming that they buy it from authorized sales points, because there will always be street cannabis available, which will certainly be less expensive and tax-free.
To your knowledge, Dr. Richardson, have veterans stopped using cannabis in favour of antidepressants?
[English]
Dr. Richardson: In my clinical experience, I’ve had lots of evidence of veterans who have discontinued cannabis use, whether for medical and recreational purposes, and have been able to respond well to pharmacotherapy, including antidepressants. My colleagues and I have had lots of evidence of veterans who were able to effectively decrease their use of cannabis and demonstrate a positive response but who continued to use a much lower dose in addition to treating their depression and PTSD with medication and talking therapy.
[Translation]
The Chair: Thank you.
[English]
Senator Griffin: Mr. Walsh, what about long-term use of medical marijuana? Does it become less effective over time?
Mr. Walsh: At least as far as we know, the tolerance that impacts the effectiveness of cannabis develops quite quickly. Most patients, in my experience, find their dose and are able to stay there. Particularly, they want to stay there and want to find the effective strain, which has been an issue. Once they find their spot, most people are able to stay there.
The hope is that, in the long term, using cannabis to reduce symptoms can help veterans engage in some of the talk and behavioural therapies that are associated with a cure to PTSD as opposed to the symptom management that cannabis brings.
Some of the best hope is that cannabis can perhaps help with sleep and some of the factors that make it difficult to engage in those behaviour therapies, because they are difficult to engage in. They often involve reliving the trauma, and they can make things a little worse before they get better. Having the supports there to help with long-term healing is one of the potentials. But for some, it will be long-term use to manage symptoms.
Senator Griffin: If someone were using recreational marijuana, would they achieve the same result as they would with medical marijuana? Will they achieve the same result in terms of allaying symptoms and helping them with other treatments?
Mr. Walsh: The cannabis itself is usually the same. The medical marijuana is more carefully characterized and should be cleaner and held to a variety of specifications, but the substance itself is generally similar. Medical versus recreational can refer to people’s authorization and motivations, but it does not necessarily refer to the quality or characteristics of the cannabis.
Senator Griffin: Dr. Pedlar, you mentioned the risk of overdose. Do you mean that could happen or does currently happen with cannabis alone, or is it more generally when it’s mixed with alcohol and other drugs besides marijuana?
Mr. Pedlar: I will probably defer some of this to my clinical colleagues. My knowledge in this area comes from reading and also from the contact I have with the emergency physician community. They commonly see overdose issues come into their space on a regular basis — perhaps on a daily basis. The accounts I’m aware of often involve the way it has been used. For example, if it is ingested, it’s much harder to keep track of how dose has been impacting your well-being. I have heard a number of quite scary stories around overdoses from people who are either innocently experimenting with it or using medical cannabis.
Mr. Walsh: To clarify what we mean by overdose with cannabis, the colloquial term is “greening out.” It’s a very unpleasant experience that lasts for several hours and is characterized by anxiety and sometimes nausea, but not long-term damage the way we see with overdose of many other medications. Fortunately, there are not cannabinoid receptors in the areas of the brain responsible for breathing so the issue that we see with the opioid epidemic and the terrible number of overdoses is something that we can’t expect to see with cannabis. An overdose, while unpleasant, usually doesn’t have long-term negative effects.
Senator Richards: This is not a statement — it might sound like a statement — but I grew up in a drug culture. There is the idea that this is going to be uniform and that there’s going to be a kind of uniform reaction. Everyone has a different reaction to taking these drugs. Someone might take them and feel fine and great; others become isolated and paranoid. I’m sure you all experienced that and know that.
I am not at all worried about people having cannabis and taking it to go to bed and relieve the nightmares and the horror of post-traumatic stress. Who would be against that? But I’m worried about the long-term effects and mixing it with alcohol. I know how every party starts and every party ends. A lot of times, they don’t end well. You start off thinking you’re going to have a few tokes and a few things, and, three days later, you’re still drunk and high. I have experienced that, and so have many of my friends.
Is this, in the long-run, going to help these guys? Is this really going to help these guys, or is this going to be just another problem that we’re creating with this? Somebody’s going to take 3 grams of marijuana, and then they’re going say, “Well, that’s not working. I can go down to the local marijuana bootlegger and get 3 or 4 more because we’re having a party.”
You have a set of criteria and rules here. I’m not sure everyone’s going to follow them. That’s all. I’m not at all saying that this isn’t going to work for some people. I’m just wondering if it’s going to work for the vast majority of people.
Dr. Richardson: As a general statement, I think that is how we would like to approach it. We currently have today effective treatments to treat PTSD, including military-related PTSD, depression, anxiety and other operational stress injuries that do not involve cannabis. I think that message needs to be promoted. However, we know that military-related or combat-related PTSD, as I mentioned already, doesn’t respond as well to treatment, whether it’s talking therapy, the psychotherapy, or the list of other medications. There is a desperate need to find more effective treatments.
However, in a clinical approach, an approach that I would find for veterans and their families and their caregivers is somebody that they can trust, with whom they can discuss: What are the options? Have I tried treatments that I know are helpful? There has been lots of news on the benefits of exercise for depression and anxiety, which has minimal side effects. Then there is the talking therapy. There’s medication. If you’ve tried what we know has been demonstrated to help but isn’t working for you, then what can you go to as your next step? That’s the approach I try to work with.
Senator Richards: Thank you very much. I am not faulting this. I am just worried about it. That is all. The idea that this is just an isolated drug is not the case. It’s a companion drug to every other drug around. It has always been a companion drug. I have grown up with this since I was 14. Marijuana and alcohol have been at every party I was ever at, and they’re mixed together continuously. I’m just thinking that it would be good if this were the case and your theories were true, and I wish they were. But I just see problems arising out of this, over the next few years. That’s all.
Mr. Walsh: If I can speak to the statements about them being used together, I agree that co-use of cannabis and alcohol is problematic. In our research, at least with students at UBC, where we’ve asked them about their co-use of cannabis and alcohol, many have said that cannabis helps them to drink less alcohol and drink more slowly, that it doesn’t motivate increased alcohol consumption. What we have seen in comparisons of U.S. states with and without medical cannabis laws is that, in those states with medical cannabis laws, there have been reductions in traffic accidents that they relate to reduced alcohol consumption on the road. Some initial evidence from Colorado shows decreasing alcohol sales together with increasing cannabis.
I agree that if cannabis is stacked on top of other substances, it is a problem. If it is used instead of, then we can compare the relative benefits and harms. Perhaps we see some public health savings. We’ve certainly seen that again in the states, where we see reduced opioid overdose in medical cannabis states.
Senator Richards: Thank you.
[Translation]
The Chair: Before we begin the second round, I have a question for our three witnesses. Do you know if cannabis use by veterans has led to it being used by other members of their family?
[English]
Dr. Richardson: That is a fascinating question. I’m not sure that I know whether or not other family members are also using, but I think it is a potential concern. However, they might already have been using as a couple, which is not that uncommon. I don’t think we have research on that. I think I’ve mentioned the benefits of not only researching the individual but also the family to see the potential benefits and impacts.
[Translation]
The Chair: You and I both know that if there is cannabis in the home, teenagers and spouses might say that, if mom or dad is using cannabis, then so can I.
[English]
Mr. Walsh: I think it will be very important to develop materials for helping people to discuss cannabis use with their children, especially if they’re using medically. There already are some materials out there. We see people using alcohol around their children. Certainly, they wouldn’t want their children to be using alcohol. It is the same with opioid pain medication. I think we can send clear messages around this being something that is for adults and not for children.
Again, I think that reducing stigma leads to open conversation. Now, I think many parents do a poor job of hiding their cannabis use from their children, and children learn the message that cannabis use is something that you hide rather than something that is discussed openly with parents. I hope that that open discussion can lead us to a situation as we have with alcohol and other drugs.
Senator Jaffer: What you have had to say has been very interesting. Now, I’m going to ask you to do a little bit of crystal balling because we are all in territories that, for most of us, are new ground.
I have so many questions about impairment. We have been hearing about cannabis not just in this committee but also in the Finance Committee and in the Legal Committee. Everywhere, we’re getting different witnesses with different points of view. I wanted to ask you all if there is a test you know of, or how does one tell if a person is impaired? Some of the things we have heard is that it depends. If somebody has been taking cannabis for a long time, their impairment is very different from somebody who is just starting. Do you have any opinion as to how you assess impairment?
Mr. Walsh: Cannabis, because of the way that it is metabolized, presents a particular puzzle when it comes to impairment. A certain nanogram blood limit can mean that you used a lot of cannabis yesterday, it can mean you recently ingested cannabis but aren’t feeling the effects yet, or it could mean you are impaired. I think we will have a lot of trouble finding some kind of per se blood limit that will be informative.
Functional tests of impairment, like the roadside sobriety-type tests, may be our best tool. Research that can refine those types of assessments, whether you are currently impaired as you are taken away from your car, will be more informative and fair given the way that cannabis is metabolized than any kind of per se limit.
Senator Jaffer: Can you repeat that?
Mr. Walsh: If you are talking about driving, if we can test how impaired people are, what their reaction time is, their executive function and attention — all those things that may be impaired — in a real-life setting, it would be more informative than blood levels, especially and combined with some kind of indication of blood levels. Blood levels on their own will be a tough test for impairment. We will need something behavioural that shows how impaired someone actually is. Unfortunately, I don’t think we’ll get something like alcohol, where you get this nice indication of how much alcohol is in someone’s blood based on a Breathalyzer. Because of the way alcohol is metabolized, that gives us a good indication. I am not hopeful we will come up with something like that for cannabis soon. As we await that, I think that functional impairment tests will be the best way to go.
Senator Jaffer: I am struggling with this because in my other life, I was a lawyer — I still am — and I did a lot of cases as defence on impairment with alcohol. There were lots of problems with those machines, when was it given, 15 minutes ago or within two hours, where it was given and how cold it was. There are so many issues.
I am thinking about what a burden it will be on the police. How will they be able to assess and then, further, how will the court hold somebody guilty on impairment? As parliamentarians and legislators, we will not be able to give any specific guidance as we do with the alcohol legislation, I don’t think; I’m not sure. I’m really concerned and I wanted to know your opinion on this.
Mr. Walsh: It is not a new issue. Currently, people are using cannabis at high levels. I don’t think it will be all that new following legislation, but I agree it is a real puzzle that the research community must address.
Senator Jaffer: I have a question with respect to prescriptions. Do you see a day when we will have a process where doctors will be prescribing cannabis as a drug for medical purposes? I know some doctors do that, but how about as a prescription?
Dr. Richardson: It is very hard to know. That is probably not one of my talents, to be able to predict the future.
If there is sufficient evidence and an indication, whether it is off label or directed through Health Canada or the FDA in the U.S., then, like any other treatment that is beneficial, I would guess the medical community would support a prescription or treatment for it. I don’t think we are there yet, but once we are there and it goes through all the regulatory approvals, then if it is indicated, I would assume it would also be supported.
Mr. Pedlar: This is longer term, but you can look at the path that a lot of medications have taken. For example, Digitalis, in its history, went back to a plant called foxglove and it took a long time to separate what was beneficial and what was harmful.
In my experience, physicians like to know what they are prescribing. Something with 87 chemicals in it is a challenge for a physician to get their head around. Generally speaking, physicians like to prescribe something built from the molecule up. I’m guessing that as we learn more about what the beneficial thing is, we will be in a better position to build medications, whether natural or synthetic, that will become more like traditional medications in terms of knowing exactly what you are giving and what the harms and benefits are.
Senator Jaffer: Thank you.
[Translation]
The Chair: Before I give the floor to Senator McIntyre, I would like to pick up on a point raised by Senator Jaffer regarding blood alcohol testing. I was a police officer and breathalyzer technician for at least twenty years. I was an operator and a qualified technician. Even though our devices had been standardized several years before, it was very difficult to win a court case based on breathalyzer results, despite the two-hour delay calculation.
In the case of drugs, we are told that police officers will be able to conduct cognitive tests and collect a blood sample within two hours. Alcohol testing is often done at night. I challenge you to find a hospital within two hours, in Abitibi, with doctors available in the emergency ward to do the tests. Such cases are not a high priority in the emergency ward. I wish the police officers good luck when they have to do drug detection tests — and I speak from experience.
[English]
Senator McIntyre: Last week, our committee heard from Dr. Courchesne, Veterans Affairs’ Chief Medical Officer. According to Dr. Courchesne, marijuana is still a controlled substance, and because it is still a controlled substance researchers have difficulty submitting research ethics proposals and passing the ethics board. You all have expertise on the state of research on this issue. Have you come up with this problem?
Mr. Walsh: In my experience with the research ethics board, in recent years there has been so much interest in doing cannabis research and so many calls for cannabis research that the research ethics board hasn’t been the primary barrier.
I think finding funding for cannabis research has been a bigger obstacle. The perspective of the scientific community on cannabis primarily as a lower consequence drug of abuse makes it less of a research priority compared to other health issues. I think an emerging lack of interest and stigma has been more of an issue.
Also, the biggest issue internationally is access to cannabis in research settings where cannabis administration is called for. It has been a puzzle trying to access the quality of cannabis required for reliable research.
Research ethics boards vary from site to site, and I can’t say that the research ethics board I have dealt with has been anything short of helpful.
Senator McIntyre: But as you said, a lack of funding, for example, would be one of the impacts on advancing knowledge in this area.
Mr. Walsh: Absolutely. A lack of funding and general stigma in the scientific community, which I hope is dissipating.
Senator McIntyre: Funding and stigma; thank you.
Senator Wallin: I have two quick follow-up questions, including warning Senator Richards not to try to travel to the United States with all your confessions here today.
Senator Richards: Not since I was 16, but they will still put me in jail.
Senator Jaffer: Not in jail, but ban you for life.
Senator Wallin: Dr. Richardson, I think you said in response to Senator Richards or Senator Dagenais that you had cases where people voluntarily stopped using cannabis and tried other alternatives. Was there any consistent reason as to why?
Dr. Richardson: That’s something we are currently studying in the sense of examining those who are currently using and have used cannabis. What are their potential benefits and reasons for decreasing? Sometimes it might have been, as was alluded to before, stigma and having family members that they didn’t want to be smoking. For others, they didn’t like the fact that they were smoking and had some adverse side effects, including feeling emotionally numb, having more anxiety and feeling stoned or not feeling themselves. So there were a variety of reasons.
Senator Wallin: That leads me to my next follow-up question. I think it was Mr. Walsh who said, in response to Senator Griffin, that there was no substantial difference between medical and recreational marijuana. We are certainly led to believe that there is less THC and more CBD in the medical so you have the benefit but not the stoned effect. Is that not the case?
Mr. Walsh: Some medical users prefer or use cannabis with higher THC. The distinction I was making is that it is not the cannabis itself that is medical or recreational but rather the motives for use and the authorization. Some recreational users may prefer cannabis with various qualities. However, yes, higher CBD cannabis is more likely to be used medically.
Senator Wallin: Thank you.
[Translation]
The Chair: Before we conclude our meeting, I have one last question for Mr. Walsh. Have you heard of a combination of medications that could be used with cannabis that would reduce the amount of cannabis needed?
[English]
Mr. Walsh: That is a great question. When I try to look forward to what will be the ideal type of cannabis therapy, it will be cannabis as an adjunct, so cannabis in addition to behaviour therapy, ideally. As caregivers, we would all like to see people to be free of medications and be able to engage in things like exercise or talk therapy and, depending on the symptoms, minimizing the amount of medications with side effects in total. So if there are medications that have less negative side effects than cannabis, I think we would want to increase those relative to cannabis. If it is a medication that has a potential harm, for instance, opioids in someone who is susceptible to opioid misuse, then increasing the relative amount of cannabis to opioid may be beneficial. On a case-by-case basis, there are situations where more cannabis or less cannabis relative to other treatments may be more or less effective.
[Translation]
The Chair: Thank you.
That concludes our meeting. Dr. Richardson, Mr. Walsh, Mr. Pedlar, thank you for your presentations and your testimony. They will be very useful when we are preparing our report.
(The committee adjourned.)