Abstract
Purpose: :
To evaluate prevalence of visual impairment and blindness, and identify demographic barriers to eye care in rural and slum areas of Chennai, India.
Methods: :
A cross-sectional study of vision status of 2558 subjects aged 5 years or older was conducted in May and June 2009 using a two-stage cluster random sampling. Visual impairment was defined as best-corrected visual acuity in the better eye (BCVA) <6/18 but >=3/60, and blindness was defined by the WHO (BCVA<3/60), Indian (BCVA<6/60), and US (BCVA<=6/60) standards. Of all the subjects, 424 aged 15 years or older responded to a structured survey on demographic background, awareness of visual burden, ability to access and acceptance of eye care.
Results: :
Prevalence of blindness was 0.72% [95% Confidence Interval 0.43-1.13%] by the WHO definition, 2.63% [2.04-3.33%] by the Indian definition, and 7.92% [6.90-9.05%] by the US definition. Prevalence of visual impairment was 12.38% [11.12-13.73%]. Cataract (12.12% [10.88-13.45%]) was the leading cause of blindness, in 94.44% (p<0.001), 89.39% (p<0.001), and 79.90% (p<0.001) of blindness by the WHO, Indian, and US standards respectively, and visual impairment (87.50%, p<0.001).Acceptance rates of medicine, eyeglasses, surgeries, and all three were 53.7% [48.9-58.6%], 87.5% [84.0-90.5%], 61.1% [56.3-65.8%], and 35.4% [30.8-40.1%] respectively, while 4.0% [2.4-6.3%] rejected all three. These acceptance/rejection rates were consistent irrespective of gender, age, education, employment, financial, and vision status. Only 15.1% [11.8-18.7%] could afford private eye care and 52.6% [47.7-57.4%] had never received previous eye examinations. In a multivariate analysis, surgery acceptance was statistically associated with self report of severe visual burden on daily life (Odds Ratio 1.85 [1.08-3.15], p 0.024) and certain regions of residence, but not with gender, age, education, employment, reception of eye care in the past, or ability to pay.
Conclusions: :
Cataract and refractive errors are the leading causes of blindness and visual impairment in this region. Resources should be allocated to address the high prevalence of cataract and preventable blindness. Lack of knowledge of eye care is consistent among most demographic groups, notably including education, employment, and financial status. Concerns for quality of local eye care services (such as medicine) and lack of eye care education also present major barriers to eye care in this region.
Keywords: clinical (human) or epidemiologic studies: prevalence/incidence • low vision • cataract