Aim: There have been inconsistent reports regarding the relationship between the iron status and coronary vascular diseases (CVD). Recently, low serum iron levels have been shown to be associated with mortality from CVD in women.
Methods: The relationships between the serum iron levels and traditional and nontraditional risk factors for CVD were examined in 202 community-living elderly Japanese women.
Results: The women in the lowest iron tertile had higher high-sensitivity C-reactive protein (hsCRP) and tumor necrosis factor-α (TNF-α) levels than the women in the top iron tertile (p<0.01 or less for both). In addition, the women in the lowest tertile had higher serum levels of adiponectin and copper and ratios of serum copper to zinc and lower serum levels of albumin, hemoglobin and hematocrit. Furthermore, the women in the lowest tertile had higher creatinine levels and lower eGFR values, although there were no significant differences in the prevalence of chronic kidney disease between the three tertile groups. In a multiple regression analysis including the levels of hsCRP, TNF-α, adiponectin and serum creatinine and the ratio of serum copper to zinc as independent variables, the levels of hsCRP, TNF-α and adiponectin emerged as independent determinants of the serum iron level (R²= 0.106). In the model to which the hemoglobin level was added as an independent variable, the levels of hemoglobin, hsCRP and TNF-α emerged as independent determinants of the serum iron level (R²= 0.192).
Conclusions: The present study demonstrated that community-living elderly Japanese women with low serum iron levels have nontraditional risk factors for CVD, including low-grade inflammation and higher levels of serum adiponectin.