Metabolic derangements in nonmodulating hypertension

A positive association exists between insulin resistance, dyslipidemia, and hypertension, specifically salt-sensitive hypertension. A subgroup of salt-sensitive normal and high renin hypertensives called nonmodulators (NM) manifest an inability to modulate the adrenal and renal blood flow responses to a change in dietary sodium. Therefore, we tested the hypothesis that the NM subgroup would be insulin resistant and dyslipidemic when compared with normal and high renin hypertensives, in whom modulation is intact (M). Forty-six nondiabetic hypertensive individuals were evaluated and their modulation status defined by either renal or adrenal criteria. Fasting blood was drawn for measurement of several metabolic factors. Since the NM group had a greater body mass index (BMI) it was subdivided into a “lean” subgroup that matched the BMI of the M group. The fasting insulin levels in both the total NM and lean NM groups was significantly higher than in the M group (P =.013 and .04, respectively). There were no differences in age, blood pressure, or plasma/serum levels of glucose, triglycerides, total cholesterol, or potassium. NM had elevated fasting insulin levels compared to M, compatible with an insulin resistant state, but this insulin resistance was not accompanied by higher lipid levels, suggesting that dyslipidemia and insulin resistance are dissociable in the hypertensive population