The impact of differing anxiety disorders on outcome following an acute coronary syndrome: time to start worrying?

Background: Both depression and anxiety have been implicated as influencing survival following an acute coronary syndrome (ACS). Studies evaluating the contribution of anxiety have produced varying results, perhaps reflecting the use of dimensional self-report measures of state anxiety and failure to control for co-morbid depression. We sought to assess the impact of anxiety on outcome in ACS patients using DSM-IV diagnoses, in addition to self-report measures, controlling for effects of concurrent depressive diagnosis as well as medical and socio-demographic variables.

Methods: Some 489 patients hospitalized with an ACS were assessed for lifetime and current DSM-IV anxiety disorders using both Composite International Diagnostic Interview (CIDI) decisions and such decisions complemented by clinical judgments of impairment. Patients were re-interviewed over the next 12 months to assess cardiac outcome (ACS readmission and cardiac mortality).

Results: Univariate analyses revealed a trend for those with a lifetime history of agoraphobia to experience poorer cardiac outcome and for those with a lifetime diagnosis of generalized anxiety disorder (GAD) to experience a superior cardiac outcome. After controlling for post-ACS depression and key medical and demographic covariates, agoraphobia was a significant predictor of poorer cardiac outcome while the trend for those with a history of GAD to experience a superior cardiac outcome remained.

Conclusions: Any impact of "anxiety" on post-ACS outcome appears to be influenced by the clinical sub-type. The seemingly paradoxical finding that GAD might improve outcome may reflect "apprehensive worrying" being constructive, by improving self-management of the individual's cardiac problems.