Circulating Insulin and Insulin Growth Factor-1 Are Independent Determinants of Left Ventricular Mass and Geometry in Essential Hypertension

Background—It is unclear whether insulin and insulin-like growth factor-1 (IGF-1) are independent determinants of left ventricular (LV) mass in essential hypertension. Methods and Results—We studied 101 never-treated nondiabetic subjects with essential hypertension. All had 24-hour noninvasive ambulatory blood pressure (ABP) monitoring and a 75-g oral glucose tolerance test. We determined fasting glucose, insulin, and IGF-1 and postload glucose and insulin 2 hours after glucose. Insulin resistance was estimated by the homeostasis model assessment (HOMAIR) formula. LV mass showed an association with body mass index (BMI) (r=0.47; P<0.01), postload insulin (r=0.54; P<0.01), HOMAIR (r=0.39; P<0.01), and IGF-1 (r=0.43; P<0.01) and a weaker association with average 24-hour systolic and diastolic ABPs (r=0.29 and r=0.26; P<0.05) and basal insulin (r=0.31; P<0.05). Relative wall thickness was positively related to IGF-1 (r=0.39; P<0.01) but not to fasting or 2-hour postload insulin, HOMAIR, and glucose. In a mul...