Components of metabolic syndrome and 5‐year change in insulin clearance – the Insulin Resistance Atherosclerosis Study

Aims Cross‐sectional evidence indicates that abdominal adiposity, hypertension, dyslipidaemia and glycaemia are associated with reduced metabolic clearance rate of insulin ( MCRI ). Little is known about the progression of MCRI and whether components of metabolic syndrome are associated with the change in MCRI . In this study, we examined the association between components of metabolic syndrome and the 5‐year change of MCRI . Methods At baseline and 5‐year follow‐up, we measured fasting plasma triglycerides ( TG ), high‐density lipoprotein ( HDL ) cholesterol, blood pressure ( BP ), waist circumference ( WC ) and fasting blood glucose ( FBG ) in 784 non‐diabetic participants in the Insulin Resistance Atherosclerosis Study. MCRI , insulin sensitivity ( S I ) and acute insulin response ( AIR ) were determined from frequently sampled intravenous glucose tolerance tests. Results We observed a 29% decline of MCRI at follow‐up. TG , systolic BP and WC at baseline were inversely associated with a decline of MCRI regression models adjusted for age, sex, ethnicity, smoking, alcohol consumption, energy expenditure, family history of diabetes, BMI , S I and AIR [ β  = −0.057 (95% confidence interval, CI : −0.11, −0.0084) for TG , β  = −0.0019 (95% CI : −0.0035, −0.00023) for systolic BP and β  = −0.0084 (95% CI : −0.013, −0.0039) for WC ; all p < 0.05]. Higher HDL cholesterol at baseline was associated with an increase in MCRI [multivariable‐adjusted β  = 0.0029 (95% CI : 0.0010, 0.0048), p = 0.002]. FBG at baseline was not associated with MCRI at follow‐up [multivariable‐adjusted β  = 0.0014 (95% CI : −0.0026, 0.0029)]. Conclusions MCRI declined progressively over 5 years in a non‐diabetic cohort. Components of metabolic syndrome at baseline were associated with a significant change in MCRI .