Serum vitamin C concentration and hs-CRP level in middle-aged Japanese men and women

ObjectiveTo examine the association between concentrations of serum vitamin C, a contributive factor to prevention of cardiovascular disease and levels of hs-CRP, a risk factor for cardiovascular disease, in population-based samples of middle-aged men and women.DesignA cross-sectional study.Methods and resultsThe subjects were 778 men and 1404 women, aged 40-69 years, who participated in a cardiovascular risk survey in Kyowa, Ibaraki prefecture in 2002 as part of the Circulatory Risk in Communities Study (CIRCS). Inverse associations between serum vitamin C concentrations and hs-CRP levels were established for both men and women. Multivariable-adjusted mean values of hs-CRP for the lowest to highest quintiles of vitamin C levels were 0.75, 0.65, 0.61, 0.61 and 0.47 mg/L (P for trend <0.001) for men, and 0.56, 0.51, 0.49, 0.41 and 0.41 mg/L (P for trend <0.001) for women. The inverse association between vitamin C and hs-CRP was stronger for non-smoking men and women, non-overweight women and postmenopausal women.ConclusionsSerum vitamin C concentrations were found to be inversely associated with hs-CRP levels in both men and women, primarily among non-smokers, non-overweight women and postmenopausal women. The respective roles of serum vitamin C and hs-CRP levels in the development of cardiovascular disease thus warrant further investigation.