Course trajectories of anxiety disorders: Results from a 6-year follow-up in a general population study

Objective: Little is known about the course of anxiety disorders in the general population. This study provides insights into the course of anxiety disorders in the general population taking into account transition to residual symptoms and to other diagnostic categories. Methods: Using data from three waves of the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2; n = 6646), subjects with anxiety disorders (T_0; n = 243) were divided into three mutually exclusive course trajectories according to their diagnostic status at 3-year (T₁) and 6-year (T₂) follow-up: remission group (no disorder at T₂), intermittent course group (no disorder at T₁ and disorder at T₂) and chronic course group (disorder at all measurements). Transition to residual symptoms or other psychopathology were studied. In addition, predictors of course trajectories were assessed. Results: During 6-year follow-up, 77.8% of subjects achieved remission, 14.0% followed an intermittent course and 8.2% a chronic course. Of those in remission, residual anxiety symptoms remained in 46.6%, while 7.9% developed another disorder between T₀ and T₂. Compared with the remitting group, a chronic course was predicted by not living with a partner, multiple negative life events, neuroticism, lower mental functioning, severity of anxiety symptoms, use of mental health care and medication use. Limitations: The intermittent and chronic course groups were small, limiting statistical power. As a result, certain predictors may not have reached significance. Conclusions: In the general population at 6-year follow-up, 77.8% of subjects with anxiety disorders achieved remission. Because of transition to residual symptoms or another diagnostic category, only 52.4% of those subjects had a true favourable outcome.