A six-year study of Japanese outpatients found longer sleep was associated with the onset or worsening of diabetic nephropathy, particularly among older adults and those with early signs of kidney damage.
A new study published in the Journal of the Endocrine Society suggests that people with type 2 diabetes who routinely sleep for longer periods may be more likely to develop or see worsening diabetic kidney disease. Researchers followed 678 Japanese outpatients for an average of about six years and found that sleep duration stood out as the lifestyle factor most closely linked to the onset or progression of diabetic nephropathy, the medical term for kidney damage caused by diabetes.
The association appeared strongest among older adults and among participants who already showed signs of kidney stress, including microalbuminuria, a condition in which small amounts of albumin leak into the urine, and reduced kidney function. According to the Endocrine Society, diabetic kidney disease affects roughly 30% to 40% of people with diabetes and is closely tied to a higher risk of end-stage kidney disease and cardiovascular complications.
Tomoya Mita, the study author at Juntendo University Graduate School of Medicine, said the findings should not be taken to mean that longer sleep is harming the kidneys directly. Speaking in the Endocrine Society’s news release, Mita said prolonged sleep may be a useful clue that identifies people who need closer monitoring of their kidney health, but he stressed that the research was observational and could not prove cause and effect.
The study adds to evidence that sleep habits may carry clinical value in diabetes care, not as a stand-alone explanation for kidney decline but as a potential marker of broader vulnerability. In practical terms, that means clinicians may want to consider sleep patterns alongside blood pressure, glucose control and kidney tests when assessing risk in people with type 2 diabetes. Other reports on the study said participants who slept at least seven hours a night had a higher risk of nephropathy progression than those sleeping less than six hours, although the researchers also emphasised that sleep itself should not be treated as the culprit.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
