Association of CRP gene polymorphisms with CRP levels, frailty and co-morbidity in an elderly Chinese population: results from RuLAS.

ABSTRACT

OBJECTIVES: to examine the associations of two common CRP gene polymorphisms with CRP levels, frailty and co-morbidity in an elderly Chinese population. DESIGN: a population-based cohort study. SETTING AND PARTICIPANTS: we obtained data on 1,723 elderly participants aged 70-84 from the ageing arm of the Rugao Longevity and Ageing study (RuLAS), a population-based observational cohort study conducted in Rugao, Jiangsu province, China. MEASUREMENTS the genotyping of two common CRP gene polymorphisms (rs1205 and rs3093059) was performed. Items concerning the frailty index and co-morbidity were collected. RESULTS: the mean age of the study population was 75.3 ± 3.9 years, and 53.5% (n = 922) were women. The minor allele frequencies of rs1205 and rs3093059 were 42.4% (C allele) and 16.9% (C allele), respectively. The polymorphisms rs1205 and rs3093059 were significantly associated with CRP levels (ß = 0.113 and 0.222, all P < 0.001). Non-significant association between rs1205 and rs3093059 and frailty, as well as between rs3093059 and co-morbidity was observed. However, SNP rs1205 CC genotype had an increased odds of co-morbidity compared with the TT genotype (odds ratio (OR)1.53; 95% confidence interval (CI) 1.16-2.02). Each additional copy of the C allele of SNP rs1205 was associated with 1.23 times (95% CI 1.07-1.41) odds of co-morbidity. The significance remained after controlling for covariates such as education level, etc. CONCLUSIONS: among elderly Chinese individuals, two CRP gene polymorphisms were significantly associated with CRP levels. However, none of them was associated with frailty. The preliminary findings warrant further validations.