Early substance use disorders and subsequent NEET-not in education, employment or training—a national cohort study

BACKGROUND: Substance use problems have been associated with poor labour market outcomes. This study investigated whether substance use disorders (SUD) in emerging adulthood increase the likelihood of later being not in employment, education or training (NEET). METHODS: A national cohort study of 23 5295 males and 227 792 females born between 1981 and 1987. SUD was assessed between ages 17 and 24 years. Logistic regression models were used to estimate the odds ratios (ORs) of NEET, between ages 25–34. Sibling-comparison analysis was performed to account for potential shared genetic and environmental factors. RESULTS: Having been diagnosed with a SUD was associated with the likelihood of being NEET among males [OR = 1.37, 95% confidence interval (CI), 1.25–1.49] and females (1.19, 1.13–1.27) after adjusting for domicile, origin, psychiatric diagnosis and parental psychiatric diagnosis. Early SUD was also associated with a gradual increase in the ORs of accumulation of years being NEET. This was more evident among females. In the sibling-comparison analysis, we found a higher OR of NEET among same-sex sibling males 1.39 (1.06–1.82) and females 1.28 (0.99–1.66) with SUD. These risks were fully attenuated when another psychiatric diagnosis was adjusted for. CONCLUSION: Early SUD was associated with an increased likelihood of being NEET in both males and females. Neither origin, domicile, psychiatric diagnoses nor parental psychiatric diagnoses did fully explain the association. The combination of unmeasured familial factors and having other psychiatric disorders largely explained these associations.