Association between serum carotenoid concentrations and risk of major age-related eye diseases among middle-aged and older adults

Background Age-related eye diseases are the main causes of progressive and irreversible vision loss in aging populations worldwide. Carotenoids, as a group of common natural antioxidants, can suppress free radicals produced by complex physiological reactions, thereby protecting the eyes from the effects of oxidative stress, cell apoptosis, and mitochondrial dysfunction. The present study aims to explore the association between serum carotenoid concentrations and risk of major age-related eye diseases among middle-aged and older adults in the United States. Methods This study involved 1,478 participants aged ≥50 years from the 2005–2006 cycles of the National Health and Nutrition Examination Survey (NHANES). Multivariate logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) of prevalence of cataract, glaucoma, diabetic retinopathy, and age-related macular degeneration (AMD) in relation to serum carotenoid concentrations. Results Compared to participants in the first quartile, those in highest quartile of serum α -carotene (OR: 0.37; 95% CI: 0.21–0.64), β -carotene (OR: 0.57; 95% CI: 0.33–0.95), lutein/zeaxanthin (OR: 0.45; 95% CI: 0.27–0.76), and total carotenoid (OR: 0.58; 95% CI: 0.35–0.97) were negatively associated with risk of cataract; those in highest quartile of serum β -carotene (OR: 0.30; 95% CI: 0.11–0.77) and β-cryptoxanthin (OR: 0.28; 95% CI: 0.12–0.68) were negatively associated with risk of diabetic retinopathy; and those in highest quartile of lycopene (OR: 0.37; 95% CI: 0.18–0.78) was negatively associated with risk of AMD. In addition, subgroup analysis results indicated that participants in highest quartile of serum α -carotene (OR: 0.16; 95% CI: 0.08–0.32), β -carotene (OR: 0.40; 95% CI: 0.21–0.75), lycopene (OR: 0.46; 95% CI: 0.24–0.87), lutein/zeaxanthin (OR: 0.45; 95% CI: 0.25–0.84), and total carotenoid (OR: 0.41; 95% CI: 0.22–0.77) concentrations were negatively associated with risk of any ocular disease among female participants. By contrast, no associations were observed among male participants. Conclusion Our study demonstrated that higher serum concentrations of carotenoids were negatively associated with the risk of age-related eye diseases, particularly among middle-aged and older female participants.