Purpose
To quantify the lifetime ocular exposure of Ultraviolet radiation and study its association with the progression of cataract among a rural and urban South Indian population
Methods
The study participants underwent a comprehensive ophthalmic examination at both the baseline and 6 year follow up visit. Lifetime ocular UV exposure was calculated based on geographical location, migration details, task analysis and use of protective eye wear details. Cataract was graded using Lens Opacities Classification System (LOCS) II. Progression of cataract and potential risk factors for the development of cataract were evaluated
Results
Lifetime UV exposure data was collected for 827 subjects (Rural: 393 and Urban 434). The mean age of the subjects was 59.4 years (SD: 9.2, Range: 44 to 97 years) and 44.7% were male. There was a significant difference in age between male and female among the rural (Male: 59.8 years, Female: 57.1 years, p= 0.03) and urban participants (Male: 63.5 years, Female: 57.9 years, p< 0.0001). Increasing age, rural residence, females, illiterates and tobacco use were significantly associated with progression of all types of cataract. Non spectacle use, Turban use, smoking, low BMI, and a myopic shift in refraction were associated with the progression of nuclear cataract (NuC) and hyperopic shift was associated with cortical cataract. Turban users, high level of lifetime ocular UV exposure, low BMI and change in refractive error towards myopia were significantly associated with the progression of posterior sub-capsular cataract . High lifetime ocular UV exposure was significantly associated with the presence of NuC and PSC at baseline and no association was noted for Cortical Cataract
Conclusions
High lifetime ocular UV exposure was significanlty associated with a 2 fold increased risk for the progression of PSC. There was no association noted with the progression of nuclear and cortical cataract
Keywords: 445 cataract •
670 radiation damage: light/UV