Purpose: To investigate the association between smoking and subcapsular cataract and blood levels of cadmium and lead, and serum levels of vitamins C, E, and beta carotene in the middle-age male population.
Subjects and methods: The present study comprised 60 cataractous male patients aged 44-55 years who attended Mansoura University Ophthalmic Center. They were divided into two groups: the first group was comprised of 15 patients who had never smoked before with minimal exposure to cigarette smoking (control group), while the second group was comprised of 45 age and body mass index-matched smokers. Blood cadmium and lead concentrations were measured and their levels in the cataractous lenses were also estimated. The levels of some antioxidants, such as serum vitamins C, E, and beta carotene, were determined.
Results: Cadmium had a statistically significant higher concentration in blood and lenses of smokers compared with that of non smokers (p < 0.0001). There was a significantly high accumulation of cadmium in the lenses of cataractous smokers reaching about a four-fold increase in heavy smokers (15.4 +/- 0.4 micromol/g) and nearly a three-fold increase in light smokers (10.1 +/- 0.4 micromol/g) when compared to that of nonsmokers (3.7 +/- 0.9 micromol/g). Regarding vitamins E, C, and beta carotene, a highly significant reduction was observed in smokers when compared with nonsmokers. There was a highly positive correlation between blood cadmium concentrations and lens cadmium levels, and blood lead concentrations and lens lead levels in heavy smokers.
Conclusion: Cadmium present in high concentrations among smokers was associated with the presence of cataracts, through induction of oxidative stress as evidenced by reduction of levels of some antioxidant studied in this work, such as vitamins E, C, and beta carotene. Thus, education of health care professionals and the public about the cataractogenic effect of cadmium is mandatory. Intake of various antioxidants may be helpful in reducing the risk of cataract formation.