The Individual and Joint Associations of Alcohol Use and Cigarette Smoking in Adolescence and Young Adulthood with Psychological Distress in Midlife – A Multicohort Study

This study examined the separate and combined associations of heavy episodic drinking (HED) and daily cigarette smoking in adolescence and early adulthood with midlife psychological distress across four prospective cohorts from Finland and Sweden: “TAM” study ( N = 1334), “FinnTwin16” ( N = 4409), “Northern Finland Birth Cohort 1966” (NFBC1966, N = 7147), and “IDA program” ( N = 514). HED was defined as self-perceived drunkenness or consumption of ≥ 60 g of pure alcohol on one occasion, smoking as daily cigarette use, and psychological distress using the 12-item General Health Questionnaire. Substance use was assessed at ages 14/16 and 22/24/25/26 years, and psychological distress at ages 35/42/46/49 years, with follow-up periods ranging from 19 to 33 years. No clear evidence emerged for individual or combined associations of HED or smoking with midlife distress, and results were overall systematic across cohorts. In contrast to prior diagnostic-focused research, these findings suggest weaker links between early substance use and later psychological distress.