Cannabis and non-psychotic mental disorders

Unhealthy behaviors associated with mental health disorders: a systematic comparative review of diet quality, sedentary behavior, and cannabis and tobacco use

Background

There are well-established literatures documenting the associations between mental disorders and unhealthy behaviors such as poor diet quality, sedentary behavior, and cannabis and tobacco use. Few studies have attempted to understand the respective findings in light of each other, however.

Objective

The purpose of this review was to assemble comparable data for each behavior-disorder association and assess the associations in terms of their overall strength. The review aimed to include a representative, but not exhaustive, range of studies that would allow for explorative comparisons.

Methods

Eligible studies were identified via Pubmed searches and citation searching, restricted to publications no older than 2015 written in English. To obtain comparable data, only studies that reported findings as odds ratios were included, and risk of bias related to study samples, behavioral measurement disparities, and control variables was assessed via sensitivity analyses. Findings for each disorder were compared on the basis of different measures of central tendency.

Results

From 3,682 records, 294 studies were included. The review found evidence of associations between each of the four unhealthy behaviors and psychosis, depression, anxiety, bipolar disorder, attention-deficit/hyperactivity disorder (ADHD), and post-traumatic stress disorder (PTSD), while personality disorder was only investigated in relation to cannabis and tobacco use. In overall comparison, the associations were generally of similar strength, and only the association between cannabis use and personality disorder was exceptional in terms of being significantly stronger than its counterparts across disorders and across behaviors. Analyses of bias risk identified some influence from behavioral measurement disparities and lack of adequate statistical control, but findings were generally robust across a range of sensitivity analyses.

Conclusion

This explorative and comparative review found that poor diet quality, sedentary behavior, and cannabis and tobacco use are about equally strongly associated with a range of different mental disorders. Given the general nature of these associations, we should probably understand them to reflect a general and shared etiology. However, the findings in this review should be regarded as tentative until confirmed by more comprehensive investigations.

Predictors of Cannabis Use Among Canadian University Students

Objective

To examine the correlates between cannabis use, motives to use, related psychosocial outcomes and academic behaviours among a sample of Canadian university students.

Methods

A random sample of 6,000 students who were enrolled in at least one class and were 18 years or over were asked to complete a cross-sectional online survey. Of the 920 students that responded, 478 (ages 18-55; mean age = 25.02, SD = 5.95) identified as having used cannabis within the past six months and thus were included as participants in the current study. Participants completed a battery of measures designed to examine cannabis use and associated constructs (i.e., substance use risk, personal well-being, non-specific psychological distress, academic behaviours, and motivations for use).

Results

Among the participants, 31% (n = 148) were found to be frequent (i.e., hazardous) users. Using cannabis for enhancement, coping, expansion, sleep difficulties, and conformity purposes, as well as impulsive personality traits were found to be predictors of cannabis use severity, with the enhancement motive identified as the strongest predictor for the total sample, males, and hazardous users. The coping motive was the strongest predictor for females, and impulsivity was the strongest predictor for non-hazardous users.

Conclusion

Findings will help inform the development of campus guidelines for lower risk cannabis use. Information gleaned from this study will also provide important information for those that use cannabis, policymakers, and health care providers in considering optimal personal use, prevention, and intervention plans.

Trends in Psychiatric Hospitalizations of Patients With Dual Diagnosis in Spain

OBJECTIVE

Substance use disorders are highly prevalent in people living with a mental health disorder. Co-occurring substance use disorders have been associated with a worse prognosis and poorer adherence to treatment. The aim of this study was to analyze the temporal trends in the prevalence of substance use disorders in patients admitted to a psychiatric inpatient unit between 1998 and 2020.

METHODS

This is a retrospective study based on the registry of 18,367 hospitalizations and 7,124 patients with a mental health disorder admitted during the period 1998 to 2020 in Malaga, Spain. Time trend analysis by gender and substance used was calculated using a segmented regression model. The permutation test was used to determine inflection points. A sensitivity analysis was performed based on the assumptions of autocorrelation and homoscedasticity.

RESULTS

A total of 22.2% of admissions had a diagnosis of mental health disorder and co-occurring substance use disorders. Prevalence was higher among males (30.0%) than females (9.4%; p < .001). Patients with both disorders had a shorter length of stay by 2 days (p < .001) and a younger age at first admission (by 6.5 years; p < .001) compared to patients without substance use disorders. There was no difference in the total number of hospitalizations between the two groups. Psychotic disorders and multiple drug use disorders were the most prevalent diagnoses in men compared to women, whereas personality disorders and alcohol use were the most common diagnoses in women. We observed an increase in the prevalence of dual diagnosis between 2005 and 2020. There was a 3.0% increase in cannabis-related admissions per year during the whole study period (p < .001). Cannabis and cocaine use disorders have become the most prevalent in the last 10 years, while opioid and alcohol use disorders have decreased.

CONCLUSIONS

Co-occurring substance use disorders are highly prevalent among hospitalized patients. In recent years, the pattern of substance use has shifted, with cannabis being the most prevalent, while opiates and alcohol substance use have decreased. We need to devise a specialized approach and integrative treatment for patients with co-occurring disorders.