C-Reactive Protein and Age-Related Macular Degeneration and Cataract: The Singapore Malay Eye Study

Abstract

Purpose. To describe associations between C-reactive protein (CRP) and age-related macular degeneration (AMD) and cataract in an Asian population. Methods. A population-based, cross-sectional study of 3280 (78.7% response) Malay persons aged 40 to 80 years was conducted in Singapore. Wisconsin grading protocols were used to grade retinal photographs for signs of early and late AMD, and lens photographs were assessed for nuclear, cortical, and posterior subcapsular (PSC) cataract. Venous blood samples were assessed for serum CRP. Results. Of 3100 (94.5%) subjects with gradable fundus photographs, 177 (5.7%) had any AMD, 155 (5.0%) early AMD, and 22 (0.7%) late AMD. No association was found between CRP and AMD. After subjects were stratified by diabetes status, the data showed that higher CRP was associated with any AMD in 2385 persons without diabetes (multivariate-adjusted odds ratio [OR], 1.73; 95% confidence interval [CI], 1.03-2.91, comparing the 4th versus the 1st quartiles of CRP). Cataract was present in 1431 (48.5%) subjects, and 634 (21.5%), 881 (29.9%) and 443 (15.0%) had nuclear, cortical, and PSC cataract, respectively. After multivariate analysis, no association was found between CRP and any cataract (OR, 0.99; 95% CI, 0.73-1.34), nuclear (OR, 0.98; 95% CI, 0.68-1.40), cortical (OR, 0.94; 95% CI, 0.71-1.23), or PSC (OR, 1.12; 95% CI, 0.81-1.55) cataract. Conclusions. In the general population, there were no associations between CRP and AMD or cataract. In persons without diabetes, higher CRP was associated with AMD. These data suggest only a weak link between systemic inflammation and AMD and cataract in Asian people.