Although there are a number of studies about substance use by medical students, the majority are still cross-sectional. We aimed to investigate prevalence, 2-year incidence, and factors associated with substance use during medical training.
This longitudinal study included medical students in 4 different waves (with each wave equaling 1 semester). Socio-demographic data, Duke Religion Index (DUREL), DASS-21, and the “Alcohol, Smoking and Substance Involvement Screening Test” (ASSIST) were used.
A total of 327 (56.2%) medical students were followed for 2 years. Prevalence of lifetime substance use was 89.9% for alcohol, 34.5% for cannabis, and 17.1% for sedatives. Tobacco had the greatest incidence of use over the 2 years (16.4%), followed by alcohol (13.8%) and cannabis (13.8%). At least 24% of the students would need an intervention for alcohol use, 11.4% for tobacco, and 6.5% for cannabis. Alcohol use during wave 4 was associated with organizational religiosity, and alcohol and tobacco use at the baseline; tobacco use during wave 4 was associated with age, non-organizational religiosity, and cannabis and tobacco use at the baseline; and cannabis use during wave 4 was associated with cannabis and tobacco use at the baseline.
Our results indicate an increase in the incidence of lifetime substance use during medical training. Prior use of substance was associated with a higher chance of use after 2 years, while age and religiousness seem to reduce the chance of use.