Antidepressant Medication Use Among Patients with Depression: Comparison between Usual Care and Collaborative Care Using Care Managers

Depression poses a significant economic and health burden, yet it remains underdiagnosed and inadequately treated. The STAR*D trial funded by the National Institute of Mental Health showed that more than one antidepressant medication is often necessary to achieve disease remission among patients seen in both psychiatric and primary care settings. The collaborative care model (CCM), using care managers, has been shown to be effective in numerous studies in achieving sustained outcomes in depression management compared to usual care. This model was adopted in a statewide depression treatment improvement initiative among primary care clinics in Minnesota, which was launched in March 2008. In this study, records of patients who were enrolled in CCM from March 2008 until March 2009 were reviewed and compared to those under usual care. Patients who were followed under the CCM had a significantly greater number of antidepressant medication utilizations when compared to those under usual care. After 6 months, mean PHQ-9 score of patients under CCM was statistically lower than those in usual care. There was no significant difference in both mean PHQ-9 scores at 6 months and antidepressant utilization between the 2 groups among patients aged 65 years and older.