The relationship between C-reactive protein levels and mortality risk

Abstract

Background. High-sensitivity C-reactive protein (hsCRP) levels are decreased in Asian compared with Western subjects. It is uncertain whether hsCRP is a potent predictor of mortality at lower CRP concentrations. The present study examined the associations of hsCRP with the risks of all-cause and cause specific mortality in Japanese population. The present study also examined the concentrations of hsCRP in Indonesian.

Methods. Subjects were 4,737 men and 6,343 women aged 49-76 years participating in the baseline survey of an ongoing cohort study of lifestyle-related diseases between February 2004 and July 2006. Hazard ratios for all-cause and cause-specific mortality associated with hsCRP levels were estimated using Cox proportional hazards regression. For hsCRP levels in Indonesian subjects, recorded hsCRP levels of patients in hospitals were referred to.

Results. A total of 436 all-cause deaths occurred during a median follow-up of 8 years. The main cause of death was cancer. In men, hsCRP levels were positively associated with the risk of all-cause mortality as well as deaths from cancer and cardiovascular disease (CVD). All-cause mortality hazards for the 2nd (0.34-0.84 mg/L) and the 3rd (≥ 0.85 mg/L) tertiles of hsCRP were 1.27 (95% confidence interval [CI], 0.93-1.73) and 1.75 (1.30-2.37) in men, respectively (p for trend=0.001). In women, increased risks of all-cause and cause-specific mortality associated with elevated hsCRP levels were observed, but the associations were not statistically significant. In Indonesian subjects, males had a higher mean CRP level compared to females.

Conclusions. HsCRP was an independent predictor of all-cause, cancer, and CVD mortality in apparently healthy Japanese men, but not women. The differential effect of hsCRP in predicting mortality risk by sex warrants further investigation. The mean CRP level in the Indonesian subjects was not too high compared to the level determined by the laboratory assessing the C-reactive protein level.