STUDY OF ROLE OF CIRCULATING ANTIOXIDANTS IN DEVELOPMENT OF SENILE CATARACT

Abstract

Introduction: Senile cataract is the commonest worldwide cause of treatable blindness, most often due to excess reactive oxygen species [ROS]. Anti-oxidant vitamins namely beta-carotene, ascorbate and tocopherol and enzymes like superoxide dismutase (SOD), constitute rst line defenses against ROS assault, while malondialdehyde (MDA) levels indicate the total burden of lipid peroxidation in-vivo. Objectives: We aimed to compare the levels of above ve analytes in senile cataract patients in contrast to apparently healthy controls and also among smoking and non-smoking sub groups of both cases and controls. Methods: A hospital-based case-control study, was conducted with 102 cases of senile cataract and 102 control subjects, following strict inclusion and exclusion criteria. Recruited individuals were sub-categorized into smokers and non-smokers. After overnight fasting (12 hours), 10 ml blood was drawn aseptically. Serum and plasma were separated and used for biochemical estimations of all ve analytes, following established protocols. Levels were compared between cases and controls as well as between the smoking and non-smoking sub-sections of both groups. Results: Signicantly lower levels of plasma ascorbate and serum tocopherol were seen in cases as compared to controls (P=0.0078 and P<0.0001 respectively). Signicantly lower levels of serum beta carotene (P<0.0001), tocopherol (P<0.0001), plasma ascorbate (P<0.0001), and SOD (P<0.0001). Signicantly higher level of serum MDA (P= 0.0494) was seen in the smokers, as compared to non-smokers Conclusions: Lowered serum tocopherol and plasma ascorbate were signicant factors leading to senile cataract. Furthermore, smoking was found crucial in loss of anti-oxidant defenses and subsequent development of cataract.