Diabetes, depression, and death: a randomized controlled trial of a depression treatment program for older adults based in primary care (PROSPECT)

Abstract

Objective: We sought to test our a priori hypothesis that depressed patients with diabetes in practices implementing a depression management program would have a decreased risk of mortality compared with depressed patients with diabetes in usual-care practices.

Research design and methods: We used data from the multisite, practice-randomized, controlled Prevention of Suicide in Primary Care Elderly: Collaborative Trial (PROSPECT), with patient recruitment from May 1999 to August 2001, supplemented with a search of the National Death Index. Twenty primary care practices participated from the greater metropolitan areas of New York City, New York; Philadelphia, Pennsylvania; and Pittsburgh, Pennsylvania. In all, 584 participants identified though a two-stage, age-stratified (aged 60-74 or >or=75 years) depression screening of randomly sampled patients and classified as depressed with complete information on diabetes status are included in these analyses. Of the 584 participants, 123 (21.2%) reported a history of diabetes. A depression care manager worked with primary care physicians to provide algorithm-based care. Vital status was assessed at 5 years.

Results: After a median follow-up of 52.0 months, 110 depressed patients had died. Depressed patients with diabetes in the intervention category were less likely to have died during the 5-year follow-up interval than depressed diabetic patients in usual care after accounting for baseline differences among patients (adjusted hazard ratio 0.49 [95% CI 0.24-0.98]).

Conclusions: Older depressed primary care patients with diabetes in practices implementing depression care management were less likely to die over the course of a 5-year interval than depressed patients with diabetes in usual-care practices.

Figure 1

Survival curves for patients with diabetes (n = 53) and patients without diabetes (n = 220) in practices randomized to Usual Care and patients with diabetes (n = 70) and patients without diabetes (n = 241) patients randomized to practices in the Intervention Condition. Data gathered from the PROSPECT study.