An Observational Study to Evaluate Dry Eye Status in Type 2 Diabetes Mellitus Patients and Its Association With Diabetic Retinopathy

Introduction Type 2 diabetes mellitus affects millions globally and frequently leads to ocular complications. This study investigated the prevalence of dry eye disease in diabetic patients and examined whether tear film dysfunction correlates with diabetic retinopathy severity. Methodology We conducted a cross-sectional observational study at the Department of Ophthalmology, Regional Institute of Medical Sciences, Ranchi, from September 2023 to December 2024. We enrolled 153 consecutive patients with type 2 diabetes and assessed them using the Ocular Surface Disease Index questionnaire, tear break-up time measurement, Schirmer's test, and fluorescein staining. Diabetic retinopathy was graded using dilated indirect ophthalmoscopy. Results Among 153 diabetic patients (mean age 55.48 ± 8.66 years, 69.28% male), 64 (41.83%) had dry eye disease. Most cases were moderate severity (21.57%). Patients with dry eye had longer diabetes duration than those without (6.00 ± 2.88 vs 4.95 ± 2.03 years, t = 2.45, p = 0.01). Diabetic retinopathy was present in 48 cases (31.37%). Dry eye severity correlated significantly with retinopathy progression (χ² = 8.76, p < 0.05). Higher HbA1c levels are associated with increased dry eye prevalence (F = 12.34, p < 0.001), with mean HbA1c rising from 6.89 ± 0.49 in unaffected patients to 8.48 ± 1.24 in severe cases. Conclusion Dry eye disease is common among patients with type 2 diabetes. Advanced age, prolonged diabetes duration, and poor glycemic control are associated with higher dry eye prevalence. The strong correlation between diabetic retinopathy severity and dry eye suggests shared pathophysiological mechanisms. These findings support comprehensive ocular surface screening in diabetic patients alongside routine retinal examination.