Collaborative care for depression yields similar improvement among older and younger rural adults

Background: Depressive disorders are among the most prevalent mental health conditions; however, significant barriers to treatment access persist. This study examined differences in depression outcomes between younger and older adults in a large-scale implementation demonstration of the collaborative care model (CoCM).

Methods: Secondary data analysis of a longitudinal, observational implementation demonstration at eight primary care clinics across low-resourced rural or frontier areas of the Western United States. Seven of these clinics were federally qualified health centers. The sample consisted of 3722 younger (18-64 years) and older (65+ years) adult primary care patients diagnosed with unipolar depression. All participants received depression treatment via CoCM, which enhances usual primary care and makes efficient use of specialists by using a behavioral healthcare manager and a psychiatric consultant to support primary care providers. Clinics were followed for up to 27 months. Patients were followed until they completed treatment or dropped out. The Patient Health Questionnaire (PHQ-9) assessed depressive symptoms at baseline (enrollment) and at most follow-up contacts. The primary treatment outcome was a change between a patient's first and last recorded PHQ-9 scores.

Results: Across both age groups, there was an average overall reduction of 6.9 points on the PHQ-9. Older adults demonstrated a greater decrease in depression scores of 2.06 points (95% CI -2.98 to -1.14, p < 0.001) on the PHQ-9 compared with younger adults. Estimates were robust when adjusting for gender, race, and clinic.

Conclusions: CoCM resulted in meaningful improvement in depressive symptoms across age groups.