Effect of insulin resistance on left ventricular hypertrophy and dysfunction in essential hypertension

Background In hypertensive patients, the relationships between glucose tole rance and left ventricular hypertrophy (LVH) and left ventricular diastolic function (LVDF) have been described in several reports. Objective In this study, we examined the relationships between insulin resi stance and LVH and LVDF in hypertensive patients from the therapeutic persp ective Methods and results The study participants were essential hypertensive pati ents with impaired glucose tolerance (IGI-HT, n = 26), hypertensive patient s with normal glucose tolerance (NGT-HT, n = 39), and normotensive control individuals (n =18). Insulin resistance was evaluated by the insulin suppre ssion test by use of the steady-state plasma glucose (SSPG) level. Left ven tricular mass index (LVMI) and LVDF, which was determined by the E:A ratio, were estimated by echocardiography. Temocapril, an angiotensin-converting enzyme inhibitor, was administered in an open, nonrandomized manner with a mean dose of 2.8 +/- 0.2 mg/day, and the mean administration period was 18 weeks. The systolic and diastolic blood pressure, the LVMI, and the SSPG le vel were significantly higher in the hypertensive patients than in the cont rol individuals. The mean systolic and diastolic blood pressures were signi ficantly decreased by treatment with Temocapril. Before treatment, stepwise regression analysis showed that SSPG is an independent predictor for LVMI and LVDF. After treatment, the changes in LVMI (D-LVMI; %) (-15.1 +/- 1.5), the changes in LVDF (D-E:A; %) (-38.2 +/- 4.1), and the changes in insulin resistance (D-SSPG; %) (-13.7 +/- 1.7) were significantly higher in the IG T-HT group than in the NGT-HT group (-11.4 +/- 1.1, -18.1 +/- 1.7, -9.4 +/- 1.4, respectively), and the D-SSPG was an independent predictor for D-LVMI and D-E:A. Conclusions The results of this study indicate that insulin resistance is a n important factor affecting LVH and LVDF. I Hypertens 1999, 17:1153-1160 ( C) Lippincott Williams & Wilkins.