Depression and panic disorder as predictors of health outcomes for patients with asthma in primary care.

INTRODUCTION: Depression and panic disorder are widely acknowledged as complicating factors in asthma patients. However, their impact on health outcomes in primary care patients is less well examined. This study prospectively evaluated the impact of depression and panic disorder on outcomes of primary care patients with asthma over 1 year.
METHODS: At baseline, 256 asthma patients from 43 primary care practices completed self-report questionnaires including the Patient Health Questionnaire (PHQ), the Asthma Quality of Life Questionnaire (AQLQ), and a structured questionnaire evaluating asthma severity, hospitalisation and emergency visits. One year later, 185 (72.3%) patients completed the same questionnaire.
RESULTS: At baseline, 3.9% of patients suffered from major depressive disorder, 22.7% from minor depressive disorder, and 7.8% from panic disorder. In the year under evaluation, 17 patients (9.2%) received emergency home visits and 10 patients (5.4%) were admitted to a hospital. Depression at baseline predicted hospitalisation within the subsequent year (OR 6.1; 95% CI 1.5-24.6) and panic disorder predicted unscheduled emergency home visits (OR 4.8; 95% CI 1.3-17.7). Depression but not panic disorder predicted the AQLQ scales activity (p=0.001), symptoms (p=0.001), emotions (p=0.001) and environment (p=0.001) at follow-up.
CONCLUSIONS: Although rates of hospitalisation and emergency visits in primary care are low, the impact of psychiatric comorbidity on health outcomes for patients with asthma is substantial. It might be helpful to identify patients with psychiatric comorbidity by analysing reasons for hospitalisation and emergency visits. For these patients, intensifying care with psychiatric interventions might help to reduce inappropriate healthcare utilisation and avoid adverse outcomes.