Systemic inflammation and eye diseases. The Beijing Eye Study

Purpose Systemic inflammation is potentially associated with ocular diseases such as late age-related macular degeneration (AMD). Using the serum concentration of high-sensitive C-reactive protein (hs-CRP) as surrogate of systemic inflammation, we examined potential associations between the serum hs-CRP concentration and the presence and degree of eye diseases. Methods The population-based Beijing Eye Study included 3468 Chinese individuals. The study participants underwent a standardized interview and a detailed ophthalmic examination. The serum concentration of hs-CRP was determined. Results Out of 3468 participants, 2452 (70.7%) individuals (mean age:63.4±9.4 year; range:50–91 years) had hs-CRP measurements (mean:1.96±4.07mg/L). In multivariate analysis, higher serum concentration of hs-CRP was significantly (regression coefficient r: 0.21) associated with a higher level of diabetic retinopathy ( P = 0.007; standardized regression coefficient beta:0.06; non-standardized regression coefficient B:1.35; 95% confidence interval (CI):0.37,2.22) and polypoidal choroidal vasculopathy ( P = 0.002;beta:0.06;B:6.22;95%CI:2.24,10.2) after adjusting for higher serum concentration of high-density lipoproteins ( P <0.001;beta:-0.12;B:-1.31;95%CI:-1.77,-0.85), higher body mass index ( P = 0.01;beta:0.06;B:0.06;95%CI:0.01, 0.11), lower level of education ( P = 0.04;beta:-0.06;B:-0.22;95%CI:-0.42,-0.02), lower cognitive function score ( P = 0.01;beta:-0.07;B:-0.08;95%CI:-0.13,-0.02). If the presences of other ocular diseases were added to the model, the presence of glaucoma ( P = 0.99), open-angle glaucoma ( P = 0.80), angle-closure glaucoma ( P = 0.67), pseudoexfoliation ( P = 0.18), nuclear cataract ( P = 0.30), cortical cataract ( P = 0.15), subcapsular cataract ( P = 0.59), retinal vein occlusions ( P = 0.33), central serous choroidopathy ( P = 0.44), early stage of age-related macular degeneration (AMD) ( P = 0.46), intermediate stage of AMD ( P = 0.20) and late stage of AMD ( P = 0.91) including geographic atrophy ( P = 0.60) or neovascular AMD ( P = 0.68) were not significantly associated with the serum concentration of hs-CRP. Conclusions In Chinese aged 50+ years, higher serum concentration of hs-CRP was significantly associated with a higher level of diabetic retinopathy and higher frequency of polypoidal choroidal vasculopathy. Other major ocular disorders, namely glaucoma including open-angle glaucoma and angle-closure glaucoma, pseudoexfoliation, nuclear, cortical or subcapsular cataract, retinal vein occlusions, central serous choroidopathy, early, intermediate or late stage of AMD including geographic atrophy, were not significantly associated with hs-CRP serum concentrations. It suggests that these diseases, in contrast to diabetic retinopathy and polypoidal choroidal vasculopathy, were not associated with a major systemic inflammatory component.