Greater body mass index is a better predictor of subclinical cardiac damage at long-term follow-up in men than is insulin sensitivity: a prospective, population-based cohort study.

Background: To examine whether lower insulin sensitivity as determined by homeostatic model assessment (HOMA-%S) was associated with increased left ventricular mass (LVM) and presence of LV diastolic dysfunction at long-term follow-up, independently of body mass index (BMI), in middle-aged, otherwise healthy males.

Methods: Prospective population-based cohort study with a median (IQR) follow-up time of 28 (27-28) years, in which traditional cardiovascular risk factors, including HOMA-%S and BMI, were assessed at baseline, and echocardiographic determination of LVM and LV diastolic function was performed at follow-up. Associations between risk factors and echocardiographic variables were tested using multivariable linear and binary logistic regression.

Results: The study population comprised 247 men with a median (IQR) age of 47 (47-48) years. Mean (SD) BMI was 25.1 +/- 3.0 kg/m(2), and median (IQR) HOMA-%S was 113.0 (68.3-284.6). Subjects with low insulin sensitivity (lowest HOMA-%S quartile (Q1)) had significantly greater BMI, fasting plasma insulin, and higher fasting blood glucose (FBG) (p <0.02 for all). BMI and HOMA-%S were significantly correlated (r = -0.383, p <0.0001). At follow-up, mean (SD) LVM and LVMI were 202 +/- 61 g and 103 +/- 31 g/m(2), respectively, whereas median (IQR) E/é was 10 (8-12). Moreover, 36 % had grade 2 or 3 diastolic dysfunction. In multivariable analyses, greater BMI, but not low insulin sensitivity was independently associated with later detection of increased LVM and diastolic dysfunction.

Conclusion: Greater baseline BMI, but not lower insulin sensitivity was independently associated with greater LVM and diastolic dysfunction at long-term follow-up.