Regional variation in diabetic retinopathy and associated factors in Spectrum of Eye Disease in Diabetes (SPEED) study in India-Report 5

Purpose: To study the zonal variations in diabetic retinopathy (DR) and associated factors in people with known type 2 diabetes mellitus (T2DM) attending large eye care facilities in different regions of India. Methods: In this cross-sectional eye-care facility-based study, India was divided into five zones; large eye care facilities with a good referral base and offering an entire range of care for patients with DR were invited. First-time T2DM attendees aged >= 18 years were recruited. All subjects received a comprehensive systemic and ophthalmic examination. DR and systemic diseases were classified as per the international/ national standards. Findings were compared between the zones and with the national average. Results: Fourteen eye-care facilities (15% public) from five zones participated. In the cohort of 11,173 people, there were more males (59%); the average age was above 45 years, and in 57%, DM had been diagnosed more than 5 years earlier. Compared with the overall study population, the proportion of people with any DR, sight-threatening DR, and blind were higher in the east zone (42.5%, 95% confidence interval [CI]: 40.2-44.8; 24.3%, 95% CI 22.3-26.3, and 11.5%, respectively); diabetic macular edema was more frequent in the south zone (12.2%, 95% CI 11.2-13.2); people with moderate-to-severe visual impairment were more in the west zone (32.1%) and higher proportion of people in the south-central zone had systemic hypertension (56.8%, 95% CI 54.8-58.9). Conclusion: The zonal variation in DR and related vision loss could be related to variable health-seeking behavior, availability, and confidence in the available services.

Automated summary

The study revealed significant zonal variations in the prevalence of DR and related factors in individuals with T2DM in different regions of India. The east zone had higher rates of DR, sight-threatening DR, and blindness, the south zone had higher rates of diabetic macular edema, the west zone had higher rates of visual impairment, and the south-central zone had higher rates of systemic hypertension.