Depression Care Management May Reduce Mortality in Older Patients With Diabetes

August 29, 2007 — Depression care management may reduce 5-year mortality in older primary care patients with both depression and diabetes, according to the results of a study published in the August 23 Publish Ahead of Print issue of Diabetes Care.
"Although cohort studies document that depression is associated with increased risk of death among persons with diabetes, no known intervention study has evaluated whether treatment for depression modifies this increased risk of mortality among older primary care patients with diabetes," write Hillary R. Bogner, MD, MSCE, from the University of Pennsylvania in Philadelphia, and colleagues. "We investigated the relationship between diabetes, depression treatment, and all-cause mortality using data from the multi-site, randomized trial, PROSPECT (Prevention of Suicide in Primary Care Elderly: Collaborative Trial), supplemented with a search of the National Death Index."
PROSPECT was a practice-randomized, controlled trial with patient recruitment from May 1999 through August 2001. At 20 primary care practices from New York City, Philadelphia, and Pittsburgh, 584 participants identified from a 2-stage, age-stratified depression screening of randomly sampled patients were classified as depressed and had complete information on diabetes status.
Of the 584 participants, 123 (21.2%) reported a history of diabetes. A depression care manager as well as primary care clinicians implemented algorithm-based care, vital status was determined at 5 years, and median follow-up was 52.0 months.
During follow-up, 110 patients with depression had died. After adjustment for baseline differences in the intervention condition (IC) and usual care (UC) groups, patients in the IC group were less likely to have died during the 5-year follow-up than were those in the UC group (adjusted hazard ratio [HR], 0.49; 95% confidence interval, 0.24 - 0.98).
"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 were depressed patients with diabetes in usual care practices," the study authors write. "We believe these findings support the integration of depression evaluation and treatment with diabetes management in primary care."
Limitations of the study include lack of generalizability to other primary care practices in the United States, diabetes mellitus based on self-report alone (some patients with impaired glucose tolerance but not diabetes may have been included), reduction in mortality in the intervention group possibly due to factors other than the specific effects of a depression management program, possible misclassification of vital status, selection of patients with diabetes from a larger intervention trial, and uncertainty regarding the effect of treatment of depression on outcomes for diabetes and other medical comorbidities.
"These results indicate that a depression care management intervention can significantly reduce all-cause mortality among depressed patients with diabetes," the study authors conclude. "These results should propel the development and dissemination of models of care that better integrate depression management for people with diabetes."
The National Institute of Mental Health supported this study. Dr. Bogner has disclosed being a faculty scholar with the Robert Wood Johnson Foundation. The remaining study authors have disclosed financial relationships with the National Institute of Mental Health.
Diabetes Care. Published online August 23, 2007.