From the Editor

Cannabis use is increasingly common. Should you be screening for misuse? What’s the role of drug testing? Do short interventions work?

In the first selection, we look at the new paper on cannabis-related disorders, published in The New England Journal of Medicine. Dr. David A. Gorelick (of the University of Maryland) comments on cannabis use disorder, offering practical suggestions, drawing on the latest in the literature (with 76 references). “Cannabis use disorder and heavy or long-term cannabis use have adverse effects on physical and psychological health.” We discuss the paper and its takeaways.

In the second selection, Jason Zhang (of the University of Michigan) and his co-authors consider surgeons and the prescribing of opioids. Given past problems, are surgeons more frugal when they reach for the prescription pad? Drawing on an impressive US database, they analyzed dispensed opioids from 2016 to 2022 in a new JAMA Network Open research letter, finding a step in the right direction – but just a step. “Despite large reductions in opioid prescribing, surgical opioid stewardship initiatives remain important.”

And in the third selection, The Globe and Mail weighs in on the recent decision to delay the expansion of medical assistance in dying, or MAiD, for mental disorders. In an unsigned editorial, the authors recognize the suffering of some, but argue that not enough has been done to define the term irremediable. “A delay is not enough.”


Selection 1: Cannabis-Related Disorders and Toxic Effects”

David A. Gorelick

The New England Journal of Medicine, 14 December 2023

Cannabis (sometimes called marijuana) is a broad term that can refer to a specific plant (genus Cannabis), the chemicals contained in the plant, their synthetic counterparts and analogues, and products derived from any of these things. The cannabis plant contains more than 500 identified chemicals, many of which are not well characterized pharmacologically, including more than 125 phytocannabinoids. The most studied phytocannabinoids are delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). THC is considered the primary psychoactive compound in cannabis, responsible for many of its psychological and physiological effects.

So begins a paper by Dr. Gorelick.

The paper covers much ground. Here, we focus on epidemiology and the cannabis use disorder.


“Cannabis is one of the most commonly used psychoactive substances globally, trailing only caffeine, alcohol, and tobacco (nicotine). Worldwide, an estimated 209 million persons 15 to 64 years of age used cannabis in 2020, representing about 4% of the global population in that age group. In the United States, an estimated 52.4 million persons 12 years of age or older used cannabis in 2021, representing 18.7% of the community-dwelling population in that age group, and 16.2 million persons met the diagnostic criteria for cannabis use disorder, which has as its core feature the use of cannabis despite adverse consequences. Cannabis use disorder occurs in all age groups but is primarily a disease of young adults.”

Cannabis Use Disorder

“Cannabis use disorder, like other substance use disorders, is a chronic, relapsing condition. The core feature is loss of control over cannabis use, which is reflected in persistent use of cannabis despite adverse consequences.”

On risk factors

“The major risk factors for development of cannabis use disorder are the frequency and duration of cannabis use. The amount and the potency of the cannabis that is used are also likely risk factors, but they have not been well studied because of the difficulty in reliably quantifying the amount and the potency of the THC content of products that are illicit at the federal level and loosely regulated at the state level. The potency of cannabis has doubled over the past 2 decades, according to analyses of samples seized by U.S. law enforcement, which may contribute to the increased risk of cannabis use disorder and cannabis-induced psychosis…”

On clinical and sociodemographic factors

“Several clinical and sociodemographic factors are associated with an increased risk of cannabis use disorder, including the use of other psychoactive substances such as alcohol and tobacco; having had adverse childhood experiences (such as physical, emotional, or sexual abuse); having a history of a psychiatric disorder or conduct problems as a child or adolescent; depressed mood, anxiety, or abnormal regulation of negative mood; stressful life events (such as job loss, financial difficulties, and divorce); and parental cannabis use…”

On screening

“The U.S. Preventive Services Task Force recommends screening all adolescents and adults in primary care settings for substance use disorders, including cannabis use disorder, as long as ‘services for accurate diagnosis, effective treatment, and appropriate care can be offered or referred.’ Screening is best done with a validated, brief instrument, to be completed by the patient, either used as a stand-alone questionnaire or embedded in a larger health questionnaire…

“A person’s own report of cannabis use or cannabis use disorder is fairly reliable if the context in which the person is asked about it poses no potential adverse consequences (e.g., criminal charges or job loss). In such contexts, 1-to-4-item screening instruments have a sensitivity of 79 to 82% and a specificity of 95% for identifying heavy cannabis use and a sensitivity of 71 to 83% and a specificity of 75 to 95% for identifying cannabis use disorder.

“An evaluation for cannabis use disorder should be triggered by a positive screening response or by signs or symptoms suggestive of cannabis use disorder. These include otherwise unexplained impairment in social, educational, or vocational functioning; exacerbation of conditions known to be worsened by cannabis (e.g., depression and anxiety); chronic conjunctival injection; yellowing of the fingertips; cannabis odor on clothing; and increased appetite.”

On treatment

“The Screening, Brief Intervention, and Referral to Treatment model should be used. Patients who are identified as having mild cannabis use disorder are offered brief intervention. Those who have moderate or severe cannabis use disorder or who did not respond to brief intervention are referred for specialty treatment…

“Brief intervention typically consists of one or two sessions, lasting 15 to 30 minutes each, of patient-centered, nonjudgmental counseling using motivational enhancement techniques. Brief intervention has short-term efficacy in reducing cannabis use and manifestations of cannabis use disorder, primarily in persons who are identified by screening and in adolescents. More intensive treatment for cannabis use disorder uses psychosocial methods. Medication plays little or no role in the treatment of cannabis use disorder.”

On psychosocial treatments

“Psychosocial treatments have significant short-term (2 to 4 months) efficacy in helping patients reduce or stop their cannabis use. Few studies of longer-term treatment outcomes have been conducted, but cannabis abstinence is usually sustained over the long term by less than 50% of patients. The most robust evidence of efficacy is for cognitive behavioral therapy (CBT) and motivational enhancement therapy (MET)… Contingency management uses behavioral reinforcement techniques to encourage specific beneficial behaviors. Typically, patients are rewarded with a voucher (redeemable for a low-value prize) each time they attend a treatment session or provide a urine sample that is negative for cannabis. There is little evidence that generic counseling for substance use disorder or attendance at mutual self-help groups such as Marijuana Anonymous (analogous to Alcoholics Anonymous) is effective in the treatment of cannabis use disorder… Patients can use a computer, tablet, or smartphone to engage in CBT, MET, and similar psychosocial treatments. Such treatments reduce cannabis use in patients with mild cannabis use disorder.”

A few thoughts:

1. This is a timely paper providing an excellent overview of the disorder.

2. It’s practical. 

3. Here are five takeaways from the big review:

  • Cannabis itself has changed. “The potency of cannabis has doubled over the past 2 decades.”
  • Screening can be helpful – even a short questionnaire – but not drug testing.
  • Medications aren’t helpful.
  • There is “little evidence” for self-help groups.
  • CBT – yes, and there’s an app or two for that, and app interventions are relevant for mild presentations.

4. Cannabis has been considered in past Readings. In October, we reflected on the fifth anniversary of Canada’s legalization of recreational use. You can find that Reading here:

The full NEJM paper can be found here:

Selection 2: “Opioid Prescribing by US Surgeons, 2016-2022”

Jason Zhang, Jennifer F. Waljee, Thuy D. Nguyen, et al.

JAMA Network Open, 7 December 2023

US surgeons prescribe opioids more frequently than surgeons elsewhere. These prescriptions often exceed patient need, increasing diversion risk. In response, policies and practice guidelines centered on opioid prescribing for acute pain have been implemented.

Timely national data on opioid prescribing by surgeons are important to inform ongoing stewardship initiatives. However, the most recent data on this prescribing come from 2019. We addressed this gap using national data from 2016 to 2022.

So begins a research letter by Zhang et al.

Here’s what they did:

“This cross-sectional study used data from the IQVIA Longitudinal Prescription Database, which captures 92% of prescriptions dispensed in US retail pharmacies… We included opioid prescriptions from surgeons dispensed between 2016 and 2022… Outcomes were the monthly surgical opioid dispensing rate (dispensed opioid prescriptions from surgeons per 100 000 people), monthly mean total morphine milligram equivalents (MMEs) per prescription (a standardized measure of prescription size), and monthly total MMEs per 100 000 people.

To assess trend changes, we fitted joinpoint regression models.” 

Here’s what they found:

  • There were 140 586 250 opioid prescriptions for 67 922 137 patients.
  • Demographics. The patients tended to be female (60.3%) with a mean age of 47.5 years.
  • Trend. “During January 2016 to December 2022, the monthly surgical opioid dispensing rate decreased from 661.2 to 426.0 prescriptions per 100 000 people (35.6%). This rate decreased 0.89%… per month during January 2016 to January 2020, declined sharply and rebounded during February to July 2020, and declined 0.45%… per month from August 2020 onward.”
  • MME. “Monthly mean total MMEs per prescription decreased from 414.0 to 222.0 prescriptions (approximately 44 pills containing 5 mg hydrocodone) during January 2016 to December 2022 (46.4%). This quantity decreased 0.47%… per month during January 2016 to May 2017 and 1.34%… during May 2017 to January 2020. After an increase and decrease during February to July 2020, this quantity declined 0.39%… per month from August 2020 onward…”
  • Orthopedics. “For orthopedic surgery, the specialty accounting for the most opioid dispensing, the opioid dispensing rate per 100 000 people declined from 301.7 to 184.9 MMEs (−38.7%) and mean total MMEs per prescription declined from 495.3 to 274.7 MMEs (−44.5%).”

A few thoughts:

1. This is a good – though not great – research letter, capturing years of data, and drawing on a robust dataset (covering 92% of US retail pharmacies).

2. A summary in seven words: good news – opioid prescribing is way down.

3. It’s interesting that the start of the pandemic saw an uptick. Did surgeons prescribe more in an attempt to address the challenges of accessing care during the lockdowns?

4. Of course, we don’t know about the actual number of opioid pills taken by patients over the study period, just the amount dispensed by pharmacies. Still, the research letter speaks to prescribing habits after a shift in medicine away from liberal opioid prescriptions.

5. The glass is half full and half empty. Yes, prescribed opioids are down, but there is still work to be done. As the authors write: “the mean size of opioid prescription from surgeons was 44 pills in December 2022, more than patients typically need. Going forward, surgical opioid prescribing guidelines based on patient-reported opioid consumption could align prescribing with patient need.” 

The JAMA Netw Open research letter can be found here:

Selection 3: A delay is not enough: Ottawa should withdraw its MAID law for the mentally ill”

The Globe and Mail, 31 January 2024

The Liberal government is trying to portray its (second) delay of the expansion of medically assisted death to those suffering solely from mental illness as a mere hiccup, a brief pause that will allow Ottawa to iron out some nagging technical issues.

‘It’s clear from the conversations we’ve had that the system is at this time not ready, and we therefore need more time,’ Health Minister Mark Holland told reporters on Monday, as the government endorsed a recommendation from a parliamentary committee to defer the enactment of the law, likely for another year.

But Mr. Holland defended the premise of the law, saying it will help Canadians who have been trapped ‘in a mental-health nightmare’ for decades and who want the relief of death ‘after trying absolutely everything.’

Those statements are misleading, both in how the government is describing the law and how it is characterizing the challenges it must surmount before it could responsibly expand medically assisted death to those suffering only from mental illness.

So begins an unsigned editorial.

They argue that: “Some European countries that offer MAID to the mentally ill have stipulated such provisions. Canada has not… Even more worrisome, the government is simply brushing aside the fundamental issue facing its MAID legislation: Is it even possible to determine if a mental illness is irremediable?”

They note the importance of that term. “Irremediability is one of the legal standards articulated by the Supreme Court in its 2015 landmark decision opening the door for medically assisted death for physical ailments.” They observe the lack of consensus within the psychiatric community itself. “Expert witnesses at the committee, who were supporters of the expansion of MAID, tried to wave away that problem, saying that clinicians deal with uncertainty as a matter of course. That is a flippant answer…”

It notes that eight provinces and three territories “asked Ottawa for an indefinite pause on its MAID expansion in order to ‘ensure a consistent and safe approach across the country that includes appropriate safeguards.’”

They conclude:

“Ottawa needs to withdraw its bill, until such time that it can demonstrate that there is a strong consensus among clinicians that irremediable mental illness can be reliably diagnosed.”

A few thoughts:

1. The editorial raise good points and is well argued.

2. Is irremediable a term that can be credibly defined? The editorialists argue no. (And you can decide how persuasive they are.)

3. Of course, many have weighed in on this issue in recent days. Some writing worth looking at:

Dr. Sonu Gaind (of the University of Toronto) has been critical of MAiD for those with mental illness. In a Toronto Star opinion piece, he suggests alternatives, including better funding of mental health care and a national suicide prevention framework.

In the Ottawa Citizen, John Scully, a former journalist, writes about his mental illness and his desire to see MAiD available for people like him. “I deserve the same rights as other patients.”

Is Canada ready to expand MAiD to those with mental disorders? The Special Joint Committee of Parliament considered that question. Their final report is worth reading, as are the dissenting opinions (at the end of the report), including the one first authored by Dr. Stan Kutcher (of Dalhousie University).

4. The debate is important but polarizing. As always, the Reading of the Week invites letters to the editor.

The full Globe editorial can be found here:

Reading of the Week. Every week I pick articles and papers from the world of Psychiatry.