Impact of coping styles on substance use in persons with psychosis, siblings, and controls

Substance use is overrepresented in patients with psychosis. Maladaptive coping has been proposed as one of the mechanisms which might underlie this high prevalence. Patients are known to apply more maladaptive coping compared to the healthy population. However, it is unknown whether coping is associated with the use of different substances across those with different vulnerability for psychosis, and whether coping mediates the possible association between life events and substance use.

In this multicenter, cohort study, 429 patients, 504 siblings, and 220 controls were included. We determined whether coping was associated with tobacco smoking, cannabis use, or alcohol consumption. Multivariable logistic regression models were applied whilst correcting for potential confounders. We performed post-hoc analyses to explore the association between negative life events, tobacco smoking, and the role of coping as a mediator in patients with psychosis.

A positive association was found in patients between passive coping and tobacco smoking (fully adjusted OR 1.65, 95% CI 1.18-2.31). Tobacco smoking patients experienced more negative life events compared to non-smoking patients and passive coping mediated this association. In siblings and controls, none of the coping strategies were associated with substance use.

The coping style of patients with psychosis is associated with tobacco smoking and mediates the association between negative events and tobacco smoking. No significant associations were found in siblings, controls or concerning other substance use. Future research is required to examine whether enhancing healthy coping strategies decreases tobacco use in patients with psychosis.