High prevalence of undiagnosed diabetes and high risk for diabetes using HbA1c criteria in middle-aged patients undergoing cataract surgery.

AIM This study assessed the prevalence of undiagnosed diabetes and a high risk for diabetes using glycated haemoglobin (HbA(1c)) values in middle-aged patients undergoing cataract surgery. METHODS The study comprised 137 consecutive patients, aged 40 to 65 years, with no known diabetes undergoing cataract surgery at a French national eye centre. Fasting glucose, obesity parameters, and vascular and ocular cataract risk factors were recorded. HbA1c was measured on the day of cataract surgery. Prevalence of undiagnosed diabetes (HbA(1c) ≥ 6.5%) and a high risk of diabetes (≥ 6.0% but < 6.5%) in the study population was compared with recently published estimates from general French, Dutch and US populations. RESULTS In the study population, undiagnosed diabetes was found in 12 patients (9%; 95% CI: 4-14%) and a high risk for diabetes in 47 (34%; 95% CI: 26-42%). These prevalences were four to 11 times higher than the corresponding population-based estimates, whereas obesity parameters recorded in the general populations and in our study population were similar according to HbA1c subcategories. Of the 125 patients with HbA1c less than 6.5%, values were higher in patients without ocular cataract risk factors (n = 73; 58%) than in those with cataract risk factors (n = 52; 42%) at 5.92 ± 0.30% and 5.57 ± 0.29%, respectively (P < 0.001), thereby suggesting a significant role for blood glucose levels in cataractogenesis. CONCLUSION Middle-aged patients undergoing cataract surgery showed a high prevalence of diabetes and a high risk for diabetes not recognized before surgery, suggesting that this patient population should be targeted for diabetes screening and prevention.