Insulinemia and blood pressure. Relationships in patients with primary and secondary hypertension, and with or without glucose metabolism impairment.

In order to investigate the relationships between insulinemia and hypertension, fasting insulinemia has been assessed in 117 subjects: 69 normotensive subjects, 36 with essential hypertension, and 12 with renovascular hypertension, all untreated and newly diagnosed, classified in subgroups (euglycemic nonobese, euglycemic obese, with impaired glucose tolerance and with non-insulin-dependent diabetes mellitus). In the patients with essential hypertension fasting insulinemia was significantly higher than in normotensive subjects (P less than .0005). The patients with secondary hypertension and the normotensive subjects had similar fasting insulinemia values. In each subgroup fasting insulinemia was higher in hypertensive patients than among normotensive subjects (P less than .05). A significant correlation between fasting insulinemia and mean blood pressure has been found in patients with essential hypertension (r = 0.408, P less than .05), but not in patients with renovascular hypertension. Our data suggest a possible direct relationship between fasting insulinemia and blood pressure, especially in obese patients or patients with impaired glucose metabolism, and that increased blood pressure per se is not an insulin resistant state.