From the Editor

It’s legal. It’s readily available. What are the implications for road safety?

Cannabis is the focus of more and more research. Little, though, has been studied for its effects on driving. In the first selection, Thomas D. Marcotte (of the University of California San Diego) and his co-authors consider cannabis and driving performance. In a new paper for JAMA Psychiatry, they report on an RCT: “In a placebo-controlled parallel study of regular cannabis users smoking cannabis with different THC content ad libitum, there was statistically significant worsening on driving simulator performance in the THC group compared with the placebo group.” We consider the paper and its clinical implications.

Next month, the American Psychiatric Association releases DSM-5-TR, the first major update to the DSM series in nine years. Though the diagnostic criteria of several disorders have been revised, there is only one new disorder: prolonged grief disorder. In the second selection, Holly G. Prigerson (of Cornell University) and her co-authors write about it for JAMA Psychiatry. “PGD is a serious mental disorder that puts the patient at risk for intense distress, poor physical health, shortened life expectancy, and suicide.”

Finally, in the third selection, we consider the life and legacy of Dr. Alan A. Stone, a psychiatrist who passed at the age of 92. In his obituary for The New York Times, reporter Clay Risen describes his incredible career – as a psychoanalyst, a Harvard professor (in both the faculties of law and medicine), and a former president of the American Psychiatric Association who championed dropping homosexuality as a psychiatric disorder.


Selection 1: “Driving Performance and Cannabis Users’ Perception of Safety: A Randomized Clinical Trial” 

Thomas D. Marcotte, Anya Umlauf, David J. Grelotti, et al.

JAMA Psychiatry, 26 January 2022

As jurisdictions legalize cannabis for medicinal and recreational use, there are growing concerns regarding a potential increased prevalence of cannabis-impaired driver. Acute consumption of Δ9-tetrahydrocannabinol (THC) negatively affects cognitive functioning and reduces driving performance, particularly in lane position control (standard deviation of lateral position) and ability to adjust to lead car speed changes (car following). However, epidemiologic data regarding the effect of legalization on crash risk are not consistent…

Questions remain regarding the magnitude and time course of the effects of cannabis on those most likely to be on the road (regular users smoking to a desired level of intoxication) as well as the effect of different product THC amounts. While seminal studies examined these questions, most used small sample sizes (eg, <25 participants), low–THC content product within a crossover design, and structured dosing protocols, with some exceptions, for example using an ad libitum approach. Such studies provide critical data regarding THC dose effects but do not reflect real-world use.

So begins a paper by Marcotte et al.

Here’s what they did:

  • They conducted a double-blind, placebo-controlled parallel randomized clinical trial between February 2017 to June 2019 involving cannabis users.
  • Participants smoked cannabis cigarettes with either 13.4% THC, 5.9% THC, or 0.02% THC (considered placebo) content.
  • They then did driving stimulations – “The simulations emulated city and country driving, including common traffic challenges (eg, freeway merging), as well as scenarios providing outcomes similar to those widely used in drug-impaired driving studies.”
  • Main outcome: “The primary end point was the Composite Drive Score (CDS), which comprised key driving simulator variables, assessed prior to smoking and at multiple time points postsmoking. Additional measures included self-perceptions of driving impairment and cannabis use history.”

Here’s what they found:

  • 191 participants were randomized.
  • Demographics. Most were men (61.8%) with a mean age of 29.9. “There were no significant group differences on key background variables.”
  • Use. They used cannabis 16.7 days (mean) in the past 30 days, approximately 0.5 g when using.
  • Crashes. There were no significant differences among the 3 groups on the number of crashes at any time point.
  • CDS scores. Compared with placebo, the THC group declined on the Composite Drive Score at 30 minutes (Cohen d = 0.59) and 1 hour 30 minutes (Cohen d = 0.55), with borderline differences at 3 hours 30 minutes (Cohen d = 0.29).
  • “The Composite Drive Score did not differ based on THC content…”
  • “Although there was hesitancy to drive immediately postsmoking, increasing numbers (68.6%) of participants reported readiness to drive at 1 hour 30 minutes despite performance not improving from initial postsmoking levels.”

A few thoughts:

1. This is a good and timely study.

2. To summarize: “In this study of 191 regular cannabis users randomized to smoke THC or placebo cigarettes ad libitum, we found worse performance in the THC group on a measure of overall driving simulator performance as well as specific driving challenges, including a divided attention task, adding to a growing literature that THC negatively impacts driving ability. The magnitude of the effect was in the medium range (Cohen d of approximately 0.5035), suggesting a nontrivial difference.”

3. Strikingly, participants were poor judges of their own driving abilities. The authors speak to a “false sense of driving safety.” Ouch.

4. When we talk to patients about cannabis use, how often do we discuss cannabis and driving? Do we caution them that their perception of driving safety may be inaccurate? This study suggests that we should do just that.

The full JAMA Psychiatry paper can be found here:

Selection 2: “Prolonged Grief Disorder Diagnostic Criteria—Helping Those With Maladaptive Grief Responses” 

Holly G. Prigerson, M. Katherine Shear, Charles F. Reynolds 

JAMA Psychiatry, 2 February 2022  Online First

The American Psychiatric Association’s DSM-5-TR presents new diagnostic criteria for prolonged grief disorder (PGD). They provide timely and important guidance for clinical practice and research given the enormous death toll from the COVID-19 pandemic both in the US and globally, complicated by the disruption of clinical practice, social support for those dying, and for the bereaved left behind. Because of the pandemic, the absolute number of PGD cases is likely to increase and the 7% to 10% prevalence rate among of bereaved people may rise. Thus, it is vital that clinicians be knowledgeable about grief reactions, know how to distinguish normal from pathological manifestations of grief, and be aware of proven treatments for it.

So begins a Viewpoint paper by Prigerson et al.

They review several aspects of the new DSM-5-TR disorder:

The Criteria

“The DSM-5-TR criteria for PGD require that distressing symptoms of grief continue for at least 12 months following the loss of a close attachment and that the grief response is characterized by intense longing/yearning for the deceased person and/or preoccupation with thoughts and memories of the lost person to a clinically significant (ie, impairing) degree, nearly every day for at least the past month. Furthermore, as a result of the death, at least 3 of the following 8 symptoms have been experienced to a clinically significant degree: (1) feeling as though a part of oneself has died, (2) a marked sense of disbelief about the death, (3) avoidance of reminders that the person has died (often coupled with intense searching for things reminiscent of the deceased person and/or evidence that they are still alive, such as mistaking others for the person who died), (4) intense emotional pain (anger, bitterness, sorrow) related to the death, (5) difficulty with reintegration into life after the death, (6) emotional numbness (particularly with respect to an emotional connection to others), (7) feeling that life is meaningless as a result of the death, and (8) intense loneliness as a result of the death. The burden of these symptoms causes clinically significant distress or impairment in social, occupational, or other important areas of functioning. The duration and severity of the bereavement reaction clearly exceeds social, cultural, or religious norms for the individual’s culture and context.”

The Treatment

“Prolonged grief disorder can also be successfully treated, as shown in 3 separate randomized clinical trials comparing a 16-session PGD-targeted therapy vs treatment efficacious for major depression.Among a total of 641 participants, the overall prolonged grief disorder therapy (PGDT) response rate, as indicated by a rating of 2 or 1 (ie, “much improved” or “very much improved”) on the Clinical Global Impression Scale, was 71% vs 44% for depression treatment using interpersonal psychotherapyor citalopram. Participants were aged 20 to 93 years, bereaved of a range of losses by natural and by violent causes. Most had already received grief counseling and/or mental health treatment. The largest of the 3 randomized clinical trials, HEAL (Healing Emotions After Loss), found no difference between citalopram and placebo in the resolution of PGD symptoms, in contrast with the markedly better response rates to PGDT than to no PGDT.”

The Central Premise

“The central premise of PGDT is that loss triggers acute grief and a natural adaptive process by which grief is transformed and integrated. A further premise is that persistence and predominance of early grief coping responses (eg, protest, self-blame, anger, counterfactual thinking, and avoidance) derail this process. The objective of PGDT is to facilitate adaptation and address these derailing symptoms.”

A few thoughts:

1. This paper is clear and useful.

2. The debate over grief and the DSM has stretched for many years (remember: with DSM-IV, there was consideration of pathological grief as a disorder). These discussions can be animated, with some feeling that grief is part of normalcy, and others arguing that this isn’t always the case. While DSM-5-TR is unlikely to settle the debate, it does tip things in favour of one camp.

3. The section on treatment in the above paper may help persuade skeptics of the usefulness of this new DSM disorder.

The full JAMA Psychiatry paper can be found here:

Selection 3: “Alan A. Stone, 92, Dies; Challenged Psychiatry’s Use in Public Policy”

Clay Risen

The New York Times, 1 February 2022

Alan A. Stone, an iconoclastic scholar who used his dual tenured appointments at Harvard’s law and medical schools to exert a powerful influence on the evolution of psychiatric ethics over the last half-century, died on Jan. 23 at his home in Cambridge, Mass. He was 92.

His son Douglas said the cause was laryngeal cancer.

Dr. Stone trained as a psychiatrist and as a psychoanalyst and began teaching at Harvard Law School in the late 1960s, just as the foundations of both fields were coming under scrutiny.

He was at the forefront of questions about how psychiatry is used as a tool of public policy; for example, he criticized the role psychiatrists played in laws that banned abortion based on claims about a woman’s mental health, and in the involuntary commitment of millions of Americans to public mental institutions.

So begins an obituary by Risen.

Dr. Stone completed his medical degree at Yale; his residency, at McLean Hospital; and his psychoanalytic training, at the Boston Psychoanalytic Society and Institute.

The essay nicely captures his diverse and eclectic career. We highlight:

  • “Despite his lack of a law degree, Dr. Stone was widely considered one of the best and most popular professors on Harvard’s legal faculty. He often taught courses with the criminal lawyer Alan M. Dershowitz, on subjects ranging from criminal insanity to Shakespeare.”
  • “In part because of his capacity for thorough, critical thinking, the Department of Justice invited Dr. Stone to join a multidisciplinary panel that would examine the 1993 raid by federal agents on a compound near Waco, Texas, that was occupied by a religious sect called the Branch Davidians.” For the record, he issued a minority report.
  • “He was for years a film critic for Boston Review, using his professional insights to tease apart movies like ‘Million Dollar Baby’ (2004), which he argued was a story about the ethics of euthanasia, and ‘The Tree of Life’ (2011), which he hailed for its treatment of Oedipal conflicts.”

Of course, his biggest influence was in the field of psychiatry itself.

The article discusses his term as APA president – “a post where, among other things, he guided the decision to remove homosexuality from the profession’s list of mental disorders.”

It also notes his break from psychoanalysis. “He declared that Freudian psychoanalysis was no longer useful as a science and was best relegated to the humanities, where it could be used to evaluate works of art. ‘Psychoanalysis, both as a theory and as a practice, is an art form,’ he said in a speech to the American Academy of Psychoanalysis. ‘I do not think psychoanalysis is an adequate form of treatment.’”

The full obituary can be found here:

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