Does the Additional Component of Calf Circumference Refine Metabolic Syndrome in Correlating With Cardiovascular Risk?

Abstract

Calf circumference (CC) was a useful anthropometric tool, but there was limited study on the effect of CC on metabolic syndrome (MetS) for cardiovascular risk. The objective of our study was to determine whether adding CC as a component of MetS refined correlating MetS with cardiovascular, all-cause, and cancer mortality risks. From the National Health and Nutrition Examination Survey data set for 1999 through 2002, we analyzed four types of MetS: (1) increased waist circumference and two or more of four MetS components (WaistMetS); (2) decreased CC and two or more of four MetS components (CalfMetS); (3) increased waist-to-calf ratio and two or more of four MetS components (WCRMetS); and (4) decreased CC and three or more of five MetS components (CC+MetS). The cause-specific hazard ratios were measured as categorized by the four types of MetS. For cardiovascular mortality, the adjusted hazard ratios for WaistMetS, CalfMetS, WCRMetS, and CC+MetS were 1.867, 1.871, 1.949, and 2.306, respectively (all P < 0.001). Notably, CalfMetS showed the strongest positive correlation with serum C-reactive protein levels, and WCRMetS had the strongest positive relationship with homeostasis model assessment of insulin resistance. Adding CC to the components of MetS correlated with higher cardiovascular and all-cause mortality risk than the traditional definition of MetS.