The study, published in the online edition of Annals of Epidemiology, showed that among people 65 and older, the mortality rate was 10 per cent per year in people who had diabetes compared to 6 per cent per year for those without diabetes, according to Alain G. Bertoni, M.D., M.P.H, and his colleagues.
What's more, the situation is getting worse, as the epidemic of diabetes spreads among people 65 and older, he said.
"The main implication of our findings is that diabetes-related mortality may be expected to increase in relative importance compared to other causes of death in the elderly, given recent trends of increasing diabetes prevalence," said Bertoni, assistant professor of public health sciences and internal medicine.
The result was something of a surprise, since several other population studies had suggested that though diabetes caused "excess mortality" in younger people, diabetes was less deadly in the elderly. "This may have led some doctors or family members not to worry much about a grandmother's touch of sugar," Bertoni said.
"These new findings suggest that prevention of diabetes among the elderly should be a priority," Bertoni said. "The Diabetes Prevention Program has shown that diabetes in high-risk individuals can be prevented." He said the program, which involves modest weight loss and physical activity, demonstrated a 71 percent reduction in diabetes incidence among those age 60 and above compared to people who just continued their normal activities.
Bertoni's study was based on a 5 percent national sample of Medicare claims in 1994, and included 148,519 persons with diabetes, matched by age, gender and race with precisely the same number of people who did not have a diagnosis of diabetes in 1994. Deaths among both groups were recorded through Dec 31, 1999. During those 60 months, 59,369 (or 40 percent) of the people with diabetes died from all causes, compared to 39,220 (or 26.4 percent) of the people who did not have diabetes. When the groups were divided into five-year subgroups by age, mortality was higher among the diabetics in each subgroup, a pattern that continued through those over 85.
When separated by race and ethnicity, the results showed that diabetes increased the risk of death by about 60 percent in African-Americans, 80 percent in whites, and more than 100 percent in Hispanics and Native Americans.
Bertoni said that among those elderly patients who already have diabetes, more research is needed because "few clinical trials have included many elderly participants." Studies are needed to determine whether treating diabetes vigorously is safe and if it can improve outcomes.
In fact, Bertoni added, "an important diabetes study, ACCORD, which is enrolling patients up to 80 years old, is already underway." There are clinical centers across North Carolina (and the nation) including three affiliated with Wake Forest Baptist.
Bertoni worked with a multidisciplinary team, including Julienne K. Kirk, Pharm D., associate professor of family medicine, David C. Goff Jr., M.D., Ph.D., professor of public health sciences and internal medicine, and Lynne E. Wagenknecht, Dr. PH, professor of public health sciences.
The study was paid for by a grant from the Center for Healthcare Research and Quality of Wake Forest University Health Sciences.
About Wake Forest University Baptist Medical Center: Wake Forest Baptist is an academic health system comprised of North Carolina Baptist Hospital and Wake Forest University School of Medicine. It is licensed to operate 1,282 acute care, psychiatric, rehabilitation and long-term care beds and is consistently ranked as one of "America's Best Hospitals" by U.S. News & World Report.