Organ-specific insulin resistance in patients with noninsulin-dependent diabetes mellitus and hypertension.

Abstract

Abnormal heart and skeletal muscle glucose metabolism in diabetes or essential hypertension has been demonstrated. However, the role of hypertension in heart and skeletal muscle glucose utilization in diabetes has not been clarified yet. We compared heart and skeletal muscle glucose utilization using PET and the whole-body glucose disposal rate (GDR) during insulin clamping in 9 patients with noninsulin-dependent diabetes mellitus (NIDDM) and essential hypertension and 11 patients with NIDDM without hypertension to examine the effect of hypertension on heart and skeletal muscle glucose utilization. Results also were compared with those for 8 asymptomatic healthy control participants. Skeletal muscle glucose utilization rate was comparable between hypertensive NIDDM patients (61.2 +/- 55.5 micromol x min(-1) x kg(-1)) and normotensive NIDDM patients (50.9 +/- 25.2 micromol x min(-1) x kg(-1)) but was significantly reduced in both groups compared with control subjects (94.2 +/- 57.3 micromol x min(-1) x kg(-1)), as was the GDR (25.2 +/- 11.3 and 24.0 +/- 7.5 micromol x min(-1) x kg(-1)), respectively, for patients compared with 38.5 +/- 11.5 micromol x min(-1) x kg(-1) for control participants). However, the myocardial glucose utilization (MGU) rate was significantly reduced in NIDDM patients without hypertension (389 +/- 185 micromol x min(-1) x kg(-1)) than in those with hypertension (616 +/- 86.4 micromol x min(-1) x kg(-1), p < 0.01). Multivariate stepwise regression analysis has shown that MGU was significantly correlated with systolic blood pressure and plasma free fatty acid concentration. Whole-body insulin resistance was observed in NIDDM patients independent of hypertension. The MGU rate may have different properties to oppose insulin resistance than glucose utilization of skeletal muscle in hypertensive patients with NIDDM.