CDC: CVD deaths decrease by 40% for diabetics

Cardiovascular disease (CVD) mortality dropped 40 percent for diabetic patients, according to findings from the National Health Interview Survey that were released by the Centers for Disease Control and Prevention (CDC) and the National Institutes of Health. These reductions may be due to improvements in the care and treatments for diabetic patients.

To help determine whether death rates (both all-cause and cardiovascular disease) declined between 1997 and 2006, Edward W. Gregg, PhD, and colleagues from the CDC in Atlanta, compared three-year death rates from four National Health Interview Samples (1997-1998, 1999-2000, 2001-2002 and 2003-2004).

“Diabetes has been associated with an average 10 years of life lost for individuals diagnosed during middle age,” the authors wrote in the June issue of Diabetes Care. However, recent improvements in glycemic control, CVD risk factors and rates of diabetes complications have helped to reduce this number.

Of patients diagnosed with diabetes and included in the survey, three-year CVD death rates were reduced by four deaths per 1,000 person-years. These reductions were 9.5 per 1,000 person-years in the 1997-1998 sample and 5.6 per 1,000 person-years in the 2003-2004 sample. After the researchers adjusted for age, sex, race/ethnicity and diabetes duration, diabetics within the 2003-2004 sample saw 40 percent lower rates of CVD mortality and a 23 percent reduction in all-cause mortality when compared with those in the earliest sample (1997-1998).

While the all-cause and CVD death rates in diabetic patients declined in both sexes, men saw greater reductions (5.2 deaths per 1,000 for men vs. 3.5 per 1,000 for women). The authors also reported that excess CVD death rates associated with diabetes declined from 5.8 to 2.3 deaths per 1,000 during the course of the study.

“The rates of improvement among those with diabetes have exceeded those of the nondiabetic population, resulting in more than a 50 percent reduction of the excess death rates that have been repeatedly attributed to diabetes,” the authors noted.

“Although excess mortality risk remains high—about two deaths per 1,000 due to CVD and about six all-cause deaths—this excess risk is now considerably lower than previous reports and consistent with improvements in several risk factors, complications, and indicators of medical care and representative of gradual, ongoing improvement in health for people with diagnosed diabetes.”

Among contributing factors, the authors listed improvements in care, self-management behaviors and medical treatments. However, the authors cautioned that the data may be limited because nearly 20 percent of persons with diabetes remain undiagnosed and some may not have self-reported the disease for the study.

“Although our analyses indicate encouraging reduction in mortality and, indirectly, continued success in diabetes care, these findings have ironic implications for the future U.S. diabetes burden,” they wrote. The authors said that while mortality rates for diabetic patients are decreasing, the disease soon will spread to a greater proportion of people in the U.S.

The researchers concluded that efforts must focus on ways to prevent vascular and neuropathic complications and to decrease diabetes-related death.