Risk factors of chronic course of anxiety and depressive disorders: a 3-year longitudinal study in the general population

Background: Risk factors of a chronic course of anxiety and depressive disorders were previously studied using a limited definition of recovery, i.e. remission of the index disorder. However, frequently, other mental disorders are present at follow-up. Thus, the course of anxiety and depressive disorders was represented too rosy and the identified determinants may not apply when using a broader, more realistic definition. Additionally, physical health risk factors have often been ignored. Methods: Data were used from two waves of the Netherlands Mental Health Survey and Incidence Study-2 including 509 respondents with 12-month anxiety disorder (panic disorder, social phobia, agoraphobia or generalized anxiety disorder) or/and major depressive disorder at baseline. Chronic course was defined as (1) presence of index disorder; and (2) presence of any anxiety, mood or substance use disorder (overall course) during the subsequent three years. Regression models were built with sociodemographic, clinical, and lifestyle/physical health indicators. Predictive accuracy was evaluated with area under the curve (AUC). Results: Chronic course of the index disorder was present among 24.8% of cases, whereas 38.7% had a chronic overall course. The accuracy of prediction of chronic course of the index disorder was suboptimal (AUC = 0.68) compared to prediction of overall course (AUC = 0.75). The main risk factors were baseline number of mental disorders, neuroticism, childhood abuse, parental psychopathology and alcohol use. Lifestyle and physical health indicators were marginally relevant. Conclusion: Transdiagnostic risk factors are important in predicting overall course of anxiety and depressive disorders but cannot accurately predict chronic course of the index disorder.