a1 Department of Medicine, Institute of Public Health and Clinical Nutrition, University of Eastern Finland, PO Box 1627, FI-70211 Kuopio, Finland
a2 Department of Internal Medicine, Lapland Central Hospital, PO Box 8041, FI-96101 Rovaniemi, Finland
Oxidative stress plays an important role in cataractogenesis. Previous studies have shown that long-term dietary intake of antioxidants (lutein and zeaxanthin) may decrease the risk of age-related cataracts. The aim of the present study was to examine whether plasma concentrations of lutein and zeaxanthin are related to age-related nuclear cataract in the elderly population. Subjects were participants in the Kuopio Ischaemic Heart Disease Risk Factor Study and they were classified into tertiles according to plasma concentrations of lutein and zeaxanthin. The association of plasma lutein and zeaxanthin concentrations with age-related nuclear cataract in 1689 elderly subjects (aged 61–80 years) was investigated in the present cross-sectional study by using the Cox proportional hazards model. A total of 113 cases of incident age-related cataracts were confirmed, of which 108 cases were nuclear cataracts. After adjustment for age, examination year, sex, BMI, smoking, alcohol consumption, serum LDL-cholesterol, serum HDL-cholesterol, years of education, use of oral corticosteroids, history of diabetes and history of hypertension with current use of antihypertensive medication, subjects in the highest tertiles of plasma concentrations of lutein and zeaxanthin had 42 and 41 % lower risks of nuclear cataract, respectively, compared with those in the lowest tertiles (relative risk (RR) = 0·58, 95 % CI 0·35, 0·98; P = 0·041 for lutein and RR = 0·59, 95 % CI 0·35, 0·99; P = 0·046 for zeaxanthin). In conclusion, we suggest that high plasma concentrations of lutein and zeaxanthin were associated with a decreased risk of age-related nuclear cataract in the elderly population.
(Received March 28 2011)
(Revised August 30 2011)
(Accepted August 30 2011)
(Online publication October 18 2011)
Abbreviations: KIHD, Kuopio Ischaemic Heart Disease Risk Factor