Low HDL cholesterol is associated with increased atherogenic lipoproteins and insulin resistance in women classified with metabolic syndrome

Both metabolic syndrome (MetS) and elevated LDL cholesterol (LDL-C) increase the risk for cardiovascular disease (CVD). We hypothesized that low HDL cholesterol (HDL-C) would further increase CVD risk in women having both conditions. To assess this, we recruited 89 women with MetS (25-72 y) and LDL-C greater-than or equal to 2.6 mmol/L. To determine whether plasma HDL-C concentrations were associated with dietary components, circulating atherogenic particles, and other risk factors for CVD, we divided the subjects into two groups: high HDL-C (H-HDL) (greater-than or equal to 1.3 mmol/L, n = 32) and low HDL-C (L-HDL) (less than 1.3 mmol/L, n = 57). Plasma lipids, insulin, adiponectin, apolipoproteins, oxidized LDL, Lipoprotein(a), and lipoprotein size and subfractions were measured, and 3-d dietary records were used to assess macronutrient intake. Women with L-HDL had higher sugar intake and glycemic load (P less than 0.05), higher plasma insulin (P less than 0.01), lower adiponectin (P less than 0.05), and higher numbers of atherogenic lipoproteins such as large VLDL (P less than 0.01) and small LDL (P less than 0.001) than the H-HDL group. Women with L-HDL also had larger VLDL and both smaller LDL and HDL particle diameters (P less than 0.001). HDL-C was positively correlated with LDL size (r = 0.691, P less than 0.0001) and HDL size (r = 0.606, P less than 0.001), and inversely correlated with VLDL size (r = -0.327, P less than 0.01). We concluded that L-HDL could be used as a marker for increased numbers of circulating atherogenic lipoproteins as well as increased insulin resistance in women who are already at risk for CVD.