Disentangling the association between alcohol consumption and employment status: causation, selection or confounding?

BACKGROUND: Alcohol use constitutes a major health risk and is related to unemployment. However, the direction of this relationship is unclear: unemployment may change drinking patterns (causation), but heavy drinkers may also be more prone to lose their job (selection). We simultaneously examined selection and causation, and assessed the role of residual confounding. Moreover, we paid attention to the subgroup of abstainers and occupationally disabled, often disregarded in the literature. METHODS: Longitudinal data (three waves collected between 2006 and 2018) of the Lifelines Cohort study from the Netherlands were used (138 875 observations of 55 415 individuals, aged 18-60 at baseline). Alcohol use was categorized as 'abstaining', 'moderate drinking' and 'binge drinking' (≥5 drinks/occasion for male; ≥4 for women). Employment status included occupational disability, short (