background A better understanding of the long-term course and consequences of anxiety disorders is important for clinical practice.
aim This study compares the diagnostic and symptom course trajectories across different anxiety disorders, and examines socio-demographic and clinical prognostic factors.
method Data were from the Netherlands Study of Depression and Anxiety (nesda). dsm-iv based diagnostic interviews and life chart assessments were used for diagnostic and symptom course trajectory over two years. In total 1010 subjects were included.
results The majority of persons with panic disorder with agoraphobia (pda, 52.7%), panic disorder without agoraphobia (pd, 72.5%), social phobia (sp, 53.5%) or generalised anxiety disorder (gad, 69.7%) were remitted within two years. Only 42.9% of the comorbid anxiety disorder (comorbid ad)  group were remitted, and this group showed a longer time to first remission and a more chronic course than pure anxiety disorders. pd and gad had a more favourable course than pda and sp. The median episode duration to first remission was four months for both pd and gad and 24 months for comorbid ad, and a chronic course was seen in 27.4% in pd, 31.7% in gad and 59.0% in comorbid ad. pda and sp had intermediate positions with respectively 23 and 18 months of median episode duration, and 49.1% and 48.3% developed a chronic course. The most important course predictors were longer  symptom duration at baseline, higher symptom severity and early age of onset.
conclusion Findings of this study indicate that a comorbid anxiety diagnosis had a much longer time to first remission and a more chronic course than a single anxiety diagnosis. pd and gad showed a more favourable course than pda and sp. Clinical characteristics, as longer symptom duration and higher symptom severity at baseline, were the most important course predictors.