Prevalence of blindness and visual impairment in a coastal region of Southern India: A cross-sectional survey in Prakasam district, Andhra Pradesh.

Purpose: To estimate the magnitude, determinants, and causes of visual impairment (VI) and blindness among people >40 years.

Methods: In this cross-sectional survey, 2,968 people >40 years from 34 clusters were examined. A cluster random sampling method with a compact segment sampling technique was used to select the study participants. Prevalence of any VI (presenting visual acuity (PVA) <6/12 in better eye), severe VI (PVA <6/60 - 3/60), and blindness (PVA <3/60 in better eye) were expressed as percentage with 95% confidence interval. Logistic regression was performed to determine the risk factors associated with blindness. A P value of less than 0.05 was considered statistically significant.

Results: The mean age of the participants was 54.6 years (Standard deviation ± 11.2 years). The prevalence of mild, moderate, and severe visual impairment was 14.2% (12.95-15.49), 13.7% (12.46-14.97), and 0.7% (0.47-1.12), respectively. The prevalence of blindness was 1.3% (0.94-1.79, n = 39). The overall prevalence of VI (presenting Visual Acuity <6/12) was 12.0% (95% CI: 10.8-13.2%). The major causes of VI were cataract (78.08%), refractive error (12.07%), and optic atrophy (2.22%), and corneal opacity (2.22%) and the major cause of blindness was cataract (77.27%). Blindness was strongly associated with increasing age- OR 17.1 (95% CI: 4.9-59.8) for people >70 years, and OR 7.6 (95% CI: 2.2-26.5) for people aged between 60 and 69 years compared to those aged 41-50 years and people living near coastal regions (Within 50 km of coast) (OR: 3.9, 95% CI: 1.6-7.3).

Conclusion: Blindness and vision impairment are of public health concern in this geographic region. Eye care services need to be augmented to address this challenge.