[Decrease of depression and outcome in treatment of anxiety disorders - an observational study of ROM data]

Most mental health hospitals in the Netherlands use disorder specific standards of care. In case of comorbidity, we lack evidence in choosing the treatment of preference when both depressive- and anxiety disorder(s) are present in the same patient.
AIM: To investigate the prevalence of depression and anxiety (including obsessive compulsive disorder and post-traumatic stress disorder) in an outpatient mental health hospital population treated for their anxiety disorder, and to investigate the difference in outcome of (anxiety) treatment between patients with and without a comorbid depressive disorder.
METHOD: A retrospective study using outcome data from 2012 to 2017. In this period, we identified 127 patients for whom outcome data and diagnostic criteria were available. Comorbidity in this group was determined by a clinical interview. During treatment symptoms were monitored using self-reporting scales, among others the Inventory of Depressive Symptomatology (IDS) and the Beck Anxiety Inventory (BAI).
RESULTS: In 46,5% of the patients a comorbid depressive disorder was diagnosed. No significant difference in treatment outcome was observed between the group of patients with and the group of patients without a comorbid depressive disorder. However, the amount of reduction of depressive symptoms measured by the ids was a good predictor of the reduction of anxiety: a faster reduction of depressive symptoms predicts a better outcome of the treatment of anxiety.
CONCLUSION: Comorbid depressive disorders were observed in almost half of the patients treated in specialized (outpatient) clinics for anxiety disorders. A slower reduction of depressive symptoms predicts worse outcome of the treatment of anxiety.