Depression Treatment for Older Diabetics Prolongs Life

PHILADELPHIA, Nov. 27 -- The five-year death rate in older depressed diabetic patients was cut in half when they received treatment for the depression, researchers here reported.
Action Points
Explain that the study found that a dedicated depression treatment program reduced death rates over five years in older diabetic patients.
Point out that the reasons for the lower death rate were unclear and may not have been entirely related to the treatment program.
After adjusting for demographic variables and other medical conditions, the hazard ratio for death was 0.49 for those in the aggressive treatment program, compared with the death rate in those receiving usual care (95% CI: 0.24 to 0.98), reported Hillary Bogner, M.D., of the University of Pennsylvania, and colleagues in the December issue of Diabetes Care.
"Depression is not only common in persons with diabetes, but contributes to not taking medicines, not following prescribed diets, and overall reduced quality of life," said Dr. Bogner.
The study used data from the Prevention of Suicide in Primary Care Elderly: Collaborative Trial (PROSPECT), which was intended to test the effectiveness of depression treatment programs in preventing suicide among the elderly. Dr. Bogner's team also used death records from a national registry to supplement the PROSPECT data.
In PROSPECT, patients with depression were assigned to usual care or to the aggressive treatment program. In the former, subjects' regular physicians were informed of the depression diagnosis and given information on depression treatment in the elderly, with actual treatment left to their discretion.
The treatment program was directed by trained care managers and followed a predetermined plan, beginning with citalopram (Celexa) and interpersonal psychotherapy. Those refusing medication were treated solely with psychotherapy. Care managers checked on patient compliance, responses, and side effects, and gave additional care at regular intervals or as needed.
Patients were followed for five years. For the diabetes study, data on a subset of 584 patients, ages 60 to 94 (mean of 70), were analyzed. Of these, 123 had diabetes, as reported by patients during a baseline interview.
During the course of the study, about 17% of nondiabetic subjects died, with little difference between the study arms. About 27% of diabetics in the treatment group died, as did 38% of diabetics assigned to usual care.
Dr. Bogner's group said it was unclear why the treatment program seemed more effective in diabetic patients. Their data did not allow analysis of the exact mechanisms underlying the treatment program's apparent effectiveness in the diabetic patients.
They suggested that "both physiologic factors, such as increased inflammation and poor glucose regulation, and behavioral processes, such as poor adherence, may link depression with increased mortality in patients with diabetes." "The potential mediators between treatment assignments and outcomes for patients with diabetes deserve further study," they said.
The group cautioned that their data had other limitations as well. For example, they relied on subjects' self-report of diabetes, although it is estimated that up to one-third of people with diabetes are unaware of it.
Also, diabetic patients in the treatment program may have had a reduced death rate for reasons not related to the treatment, the report said. Patients in that group could have been seen by their physicians more frequently and therefore received better care for other conditions.
"Statisticians are wary of subgroup analyses," the report acknowledged as well. "At the same time, large-scale intervention studies carried out in primary care practice are limited, so we need to make the most of the data we have."
Both PROSPECT and the diabetes subgroup study were funded by the National Institute of Mental Health.
No disclosure was made about financial relationships with for-profit companies.Primary source: Diabetes CareSource reference: Bogner H, et al "Diabetes, depression and death: A randomized controlled trial of a depression treatment program for older adults based in primary care (PROSPECT)" Diabetes Care 2007; 30: 3005-10.