Elevated fasting glucose levels within normal range are associated with an increased risk of metabolic syndrome in older women

Objective: The prevalence of cardiovascular disease (CVD) and metabolic syndrome (MetS) increases with increasing fasting plasma glucose (FPG) levels in an elderly population with pre-diabetes or diabetes. However, it remains unknown whether the relationship between elevated FPG and increased risks of MetS exists in older women with normoglycemia (FPG<100mg/dL). Therefore, the present study was conducted to fill the lack of information in that area.

Materials and methods: We included 6505 apparently healthy women, aged 65years and older, with normoglycemia who participated in routine health checkups at health screening centers in Taiwan. Components of MetS (FPG, waist circumference (WC), high-density lipoprotein cholesterol (HDL-C), triglycerides, and systolic/diastolic blood pressure), body mass index (BMI), low-density lipoprotein cholesterol (LDL-C), total cholesterol, and percentage body fat (PBF) were examined in all subjects.

Results: Subjects were sub-grouped by FPG levels (<90mg/dL, 91-95mg/dL and >95mg/dL for group 1, group 2 and group 3, respectively). Subjects in group 2 and group 3 were 1.22-fold (P=0.017) and 1.25-fold (P=0.007) more likely to have MetS compared with those in group 1. Age, WC, BMI, PBF, systolic and diastolic blood pressure, total cholesterol, triglycerides, and HDL-C were significantly correlated with FPG, whereas HDL-C was negatively correlated with FPG. In a multivariate stepwise regression analysis, PBF, LDL-C, triglycerides, and age were significantly and independently associated with FPG.

Conclusion: Among older women, the risk of MetS was significantly associated with elevated FPG even for subjects with normal FPG. Lifestyle interventions for reducing PBF and controlling dyslipidemia could help reduce the risk of MetS in this population.