Diabetic retinopathy (DR) remains a common complication for diabetic patients, where Retinal physiological function is affected by hydration status.

A recent study explored the association between hydration status and DR. It used National Health and Nutrition Examination Survey (NHANES) 2005-2008 results to perform this cross-sectional study. 

The study assessed serum osmolality to identify the hydration status of all participants and evaluated the osmolality for older people only. It evaluated DR and its severity and graded them into mild non-proliferative retinopathy, moderate/severe non-proliferative retinopathy, and proliferative diabetic retinopathy using the Early Treatment for Diabetic Retinopathy Study protocol and NHANES Digital Grading Protocol. 

• Among the 5,220 adults aged 40 or older, participants with the highest quartile of serum osmolarity showed higher odds of DR.
• For participants with DR, the adjusted OR of moderate/severe non-proliferative retinopathy and proliferative diabetic retinopathy in the higher serum osmolarity group was found as 2.119 and 7.001, respectively.
• In older people, higher calculated osmolarity showed a significant association with increased occurrence of DR.

This study shows that adults with lower hydration status have a higher risk of DR, moderate/severe non-proliferative retinopathy, and proliferative diabetic retinopathy. Dehydration in older adults, classified by calculated osmolality, is responsible for a higher rate of DR. The two methods showed a consistent trend in the results.

Zhang J, Ren Z, Zhang Q, et al. Lower hydration status increased diabetic retinopathy among middle-aged adults and older adults: Results from NHANES 2005-2008. Front. Public Health. 2022. https://doi.org/10.3389/fpubh.2022.1023747