Deprivation and Visual Impairment in Pakistan. The National Blindness and Visual Impairment Survey

Abstract

Purpose:: To explore the association between visual impairment and deprivation in Pakistan.

Methods:: Visually impaired adults (≥30years) were identified in a population based national survey in Pakistan. A deprivation score (at district level stratified by urban/rural location; 0 = least, 100 = highest deprivation) similar to the UNDP’s Human Poverty Index, was obtained from national census data. Subjects were categorized as living in low (<25^th centile), medium (25-75^th centile) or high deprivation (>75^th centile) areas.

Results:: 16,507 (95.3% response rate) participants were examined. Adults in Sindh province had the lowest deprivation whereas rural areas in Balochistan had the highest.The prevalence of blindness (<3/60 in the better eye) in adults with low deprivation was 2.2%, compared with 3.7% in medium and 3.9% in high deprivation areas (p<0.001). The highest prevalence of blindness was found in rural Balochistan (5.2%). The prevalence of total blindness (bilateral no light perception) was more than three times higher in highly deprived areas compared to low deprivation areas (0.24% vs. 0.07%, p<0.001).Cataract was the leading cause of blindness in all areas (51.5%), and in high deprivation areas the proportion was 52.8% compared with 46.9% in low deprivation areas (p<0.001). In adults with <6/18 in the better eye, cataract remained the leading cause in the high and medium deprived areas (47.2% and 49.4% respectively) but uncorrected refractive error was the leading cause in low deprivation areas (40.1%).10.2% of adults in low deprivation areas presented with spectacles compared to 6.7% and 4.4% in medium and highly deprived areas respectively. Spectacle coverage was more than double in low deprivation areas compared to high deprivation areas (24.8% vs 11.8%, p<0.001). Reflecting access to eye care, the cataract surgical coverage was highest in the least deprived areas (80.6%) compared to 76.8% and 75.1% in the medium and highest deprived areas.

Conclusions:: Visual impairment and poor access to services is associated with deprivation. Control strategies need to focus on poor communities, and combating visual impairment may impact on global deprivation.

Keywords: clinical (human) or epidemiologic studies: risk factor assessment