Association of Retinopathy and Insulin Resistance: NHANES 2005-2008

Purpose: In animal models, insulin resistance without severe hyperglycemia is associated with retinopathy; however, corroborating data in humans are lacking. This study aims to investigate the prevalence of retinopathy in a population without diabetes and evaluate the association of insulin resistance and retinopathy within this group. Methods: The study population included 1914 adults age >= 40 without diabetes who were assigned to the morning, fasted group in the National Health and Nutrition Examination Survey 2005-2008, conducted by the Centers for Disease Control. Retinopathy was determined using fundus photos independently graded by a reading center and insulin resistance was determined using the homeostatic model of insulin resistance. Results: Prevalence of retinopathy in those without diabetes was survey design adjusted 9.4% (174/1914). In multivariable analyses, retinopathy was associated with insulin resistance (HOMA-IR OR: 1.09, 95% CI: 1.03, 1.16; p = .0030), male gender (OR: 1.39, 95% CI: 1.04, 1.85; p = .0267), and age (OR: 1.03, 95% CI: 1.01, 1.05; p = .0203). Conclusions: Insulin resistance in the absence of overt hyperglycemia could be an early driver of retinopathy.