Longer sleep duration linked to diabetic kidney disease risk

People with type 2 diabetes who sleep longer may have an increased risk of developing or worsening existing diabetic kidney disease, according to a study published in the Journal of the Endocrine Society.

Diabetic nephropathy, also known as diabetic kidney disease, is a serious kidney condition caused by long-term damage from type 1 or type 2 diabetes. It is among the most prevalent and severe complications of diabetes, affecting approximately 30% to 40% of people with the condition. It is strongly associated with the development of end-stage kidney disease and an increased risk of cardiovascular events.

Diabetic kidney disease is a major complication of diabetes and can eventually lead to kidney failure and an increased risk of cardiovascular disease. Sleep is a simple and routinely experienced aspect of daily life, so our findings suggest that longer sleep duration may provide a useful clue to identify people with diabetes who may need closer attention to their kidney health. At the same time, people should not interpret our findings as a recommendation to reduce their sleep, since this was an observational study and we cannot establish a causal relationship between sleep duration and kidney disease."

Tomoya Mita, M.D., Ph.D., study author, Juntendo University Graduate School of Medicine, Tokyo, Japan

The researchers studied 678 Japanese people with type 2 diabetes and found longer habitual sleep duration was associated with a higher risk of developing or worsening diabetic nephropathy during approximately six years of follow-up.

The association was particularly evident among older adults and those who already had signs of kidney damage, such as microalbuminuria or reduced kidney function.

"Importantly, our findings do not show that long sleep directly causes kidney disease; rather, longer sleep may be a readily observable marker of underlying health vulnerability," Mita said.

Other authors are Fuki Ikeda, Yusuke Osonoi, Yuki Someya, Shiho Nakayama and Hirotaka Watada of Juntendo University Graduate School of Medicine; Takeshi Osonoi, Miyoko Saito and Hidenori Ishida of Naka Kinen Clinic in Ibaraki, Japan; and Ryota Ishii and Masahiko Gosho of the University of Tsukuba in Tsukuba, Ibaraki, Japan.

The study was funded by the Manpei Suzuki Diabetes Foundation.