ROLE OF GLUCOSE-INTOLERANCE IN CARDIAC DIASTOLIC FUNCTION IN ESSENTIAL-HYPERTENSION

Insulin resistance and glucose intolerance have been suggested to be i nvolved in the pathogenesis of various cardiovascular diseases. We exa mined the role of glucose intolerance in cardiac performance and cardi ac hypertrophy in 33 patients with essential hypertension (28 to 71 ye ars of age, mean+/-SD: 53+/-13 years) who had never been treated. Pati ents with obesity (body mass index>30 kg/m(2)) or overt diabetes were excluded. Plasma glucose and insulin were measured after oral administ ration of 75 g glucose. The incremental areas of glucose and insulin w ere used as indices of glucose intolerance and insulin resistance, res pectively. Patients with impaired glucose tolerance according to World Health Organization criteria (n=12) showed a significantly higher rat io of peak velocity during atrial contraction to early left ventricula r filling phase (A/E ratio) than those with normal glucose tolerance ( n=21) despite similar age, blood pressure, and left ventricular mass i ndex. By regression analysis, left ventricular mass index positively c orrelated with systolic blood pressure (r =.392, P<.05) but not with a ny parameters of glucose and insulin metabolism. A/E ratio determined by a Doppler system significantly correlated with age (r=.776) and fas ting and peak levels and incremental area of plasma glucose (r=.529, r =.468, and r=.634) but not with those parameters of insulin. In contra st, ejection fraction was not related to blood pressure, glucose toler ance, or insulin resistance. These results suggest that glucose intole rance does not play an important role in cardiac hypertrophy in essent ial hypertension but partly contributes to the cardiac diastolic dysfu nction that develops early in these patients.