Substance Use Disorders Among College Students In Chennai: Pattern, Prevalence And Associated Psychiatric Comorbidities

Background: Substance use among college students is a growing public health concern globally. In India, limited data exists on the prevalence, patterns, and psychiatric comorbidities associated with substance use in college populations, particularly using standardized diagnostic instruments. Understanding these associations is crucial for developing targeted prevention and intervention strategies. Objective:To determine the prevalence and patterns of substance use among college students in Chennai, examine associations with depression and anxiety, assess impact on academic performance, and identify independent predictors through multivariate analysis. Methods: A cross-sectional study was conducted among 612 college students from six colleges in Chennai during September to October 2025. Substance use was assessed using standardized questionnaires. Depression (PHQ-9), anxiety (GAD-7), and academic performance were evaluated. Statistical analysis included chi-square test, t-test, ANOVA, Pearson correlation, and multiple logistic regression. Results: Overall substance use prevalence was 28.4 %. Alcohol was most common (22.1 %), followed by tobacco (18.3 %) and cannabis (7.5 %). Male students showed significantly higher prevalence (40.5 % vs 14.2 %, p<0.001). Poly-substance use was present in 11.6 %. Depression was present in 41.4 % of substance users vs 18.7 % of non-users (OR=3.06, p<0.001). Anxiety prevalence was 38.5 % vs 16.2 % (OR=3.24, p<0.001). Substance users had lower CGPA (6.8±1.4 vs 7.8±1.2, p<0.001). Independent predictors included peer substance use (OR=4.42), male gender (OR=3.83), family history (OR=2.44), depression (OR=2.28), and anxiety (OR=2.11). Only 13.8 % sought professional help. Conclusion: Substance use prevalence among Chennai college students is high with significant psychiatric comorbidities and academic impairment. Strong associations with depression, anxiety, and poor academic performance necessitate comprehensive prevention programs and accessible mental health services in colleges.