C-reactive protein and diabetic retinopathy in Chinese patients with type 2 diabetes mellitus

AIM: To investigate the relationship between C - reactive protein (CRP) and diabetic retinopathy (DR) in a cohort of Chinese patients with type 2 diabetes mellitus (T2DM). METHODS: Community -based observational cohort study. There were 1131 participants recruited from November 2009 to September 2011 in Desheng community in urban Beijing. Patients diagnosed T2DM were recruited and underwent a standardized evaluation consisting of a questionnaire, ocular and anthropometric examinations and laboratory investigation. The presence and severity of DR were assessed by seven fields 300 color fundus photographs. Subjects were then classified into groups with no DR, any DR, or vision -threatening DR. CRP was analyzed from serum of study subjects. RESULTS: A total of 1007 patients with T2DM were included for analysis, including 408 (40.5%) men and 599 (59.5%) women. The median CRP level was 1.5 mg/L for women and 1.1 mg/L for men (P=0.004, OR 0.37, 95% CI 0.18-0.74). After adjusting for possible covariates, higher levels of CRP were associated with lower prevalence of any DR (P=0.02, OR 0.55, 95% CI 0.35-0.89), but not associated with vision-threatening DR (P=0.62, OR 0.78, 95% CI 0.28-2.14). After stratification by sex, the inverse association between CRP and DR was found to be statistically significant in men (P=0.006, OR 0.35, 95% CI 0.16-0.73), but not in women (P=0.58, OR 0.88, 95% CI 0.29-1.16). CONCLUSION: The data drawn from a Chinese population with T2DM suggest that increasing CRP levels may be inversely associated with development of DR.