Kidney disease accounts for most of the increased risk of dying early among diabetics

Because people with diabetes have an increased likelihood of dying prematurely as well as an increased likelihood of developing kidney disease, Maryam Afkarian, MD, PhD (University of Washington) and her colleagues looked to see how the former affects the latter. In other words, how much does kidney disease contribute to diabetics' increased risk of dying early?

The researchers examined 10-year mortality rates in 15,046 US adults. Kidney disease was present in 9.4% and 42.3% of individuals without and with type 2 diabetes, respectively.

Among the major findings: • Among people without diabetes or kidney disease, 10-year mortality was 7.7%. • Among individuals with diabetes but without kidney disease, mortality was 11.5%. • Among individuals with both diabetes and kidney disease, mortality was 31.1%.

"People with type 2 diabetes have many other risk factors for cardiovascular disease and mortality, so we expected that kidney disease would predict a part, but not a majority, of higher mortality associated with type 2 diabetes. To our surprise, we found that even in the medically complex patients with type 2 diabetes, kidney disease is a very powerful predictor of premature death," said Dr. Afkarian.

She noted that the findings have important implications. "First, among people with type 2 diabetes, the subgroup with kidney disease carries most of the mortality risk, so targeting intensive risk factor modification on this subgroup is likely to have the highest impact on overall mortality of people with diabetes. Secondly, preventing kidney disease may be a powerful way of reducing mortality in people with diabetes," said Dr. Afkarian.

Study co-authors include Michael Sachs, PhD, Bryan Kestenbaum, MD, MS, Irl Hirsch, MD, Katherine Tuttle, MD, FACP, FASN, Jonathan Himmelfarb, MD, and Ian de Boer, MD, MS (University of Washington).