[Prevalence of cannabis use in Primary Care]

To estimate the prevalence of cannabis use among adults attending primary care, identify the age of initiation and associated sociodemographic characteristics, and describe patterns of dependence risk.

A cross-sectional descriptive study was conducted in three primary healthcare centres in the Barcelona metropolitan area. Adults aged 18 - 45 years were selected by simple random sampling. Telephone interviews used cannabis related questions from the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST), validated by the World Health Organization. Cannabis use prevalence and dependence risk were analysed by sociodemographic characteristics using multiple logistic regression.

Of 237 individuals contacted, 221 participated (93.25%). Among the participants, 58.8% were women, with a mean age of 33.5 years (SD = 8.1). Overall, 53.4% had used cannabis at least once in their lifetime, with a mean age of initiation of 18.4 years (SD = 4.1). Among lifetime users, 25.4% had a moderate risk of dependence. After adjustment for age and socioeconomic status, cannabis use was more likely among men than women (OR = 2.11; 95% CI: 1.21-3.72). Overall, 22.9% had used cannabis within the previous three months, and 81.5% of these users had a moderate risk of dependence. Moderate dependence risk was more frequent with lower educational attainment.

Cannabis use prevalence exceeded that reported in previous studies and was higher in men. One-quarter of lifetime cannabis users had a moderate risk of dependence according to the ASSIST, particularly those with lower educational attainment.