Impact of symptom remission on outpatient visits in depressed primary care patients treated with collaborative care management and usual care.

Depression symptoms contribute to significant morbidity and health care utilization. The aim of this study was to determine the impact of symptom improvement (to remission) on outpatient clinical visits by depressed primary care patients. This study was a retrospective chart review analysis of 1733 primary care patients enrolled into collaborative care management (CCM) or usual care (UC) with 6-month follow-up data. Baseline data (including demographic information, clinical diagnosis, and depression severity) and 6-month follow-up data (Patient Health Questionnaire scores and the number of outpatient visits utilized) were included in the data set. To control for individual patient complexity and pattern of usage, the number of outpatient visits for 6 months prior to enrollment also was measured as was the presence of medical comorbidities. Multiple logistic regression analysis demonstrated that clinical remission at 6 months was an independent predictor of outpatient visit outlier status (>8 visits) (odds ratio [OR] 0.609, confidence interval (CI) 0.460-0.805, P<0.01) when controlling for all other independent variables including enrollment into CCM or UC. The OR of those patients not in remission at 6 months having outpatient visit outlier status was the inverse of this at 1.643 (CI 1.243-2.173). The most predictive variable for determining increased outpatient visit counts after diagnosis of depression was increased outpatient visits prior to diagnosis (OR 4.892, CI 3.655-6.548, P<0.01). In primary care patients treated for depression, successful treatment to remission at 6 months decreased the likelihood of the patient having more than 8 visits during the 6 months after diagnosis.