Longitudinal Changes of Insulin Sensitivity in Essential Hypertension: Influence of Blood Pressure Control and Familial Predisposition to Hypertension

Abstract

The aim of this study was to evaluate the influence of blood pressure (BP) control and familial predisposition to hypertension on longitudinal changes in insulin sensitivity in essential hypertension. We evaluated 6 groups of subjects twice (basal: before any treatment; 2nd: after at least 18 months): 42 hypertensives (H) with a family history of hypertension (F+) and 30 H without a family history of hypertension (F-) successfully treated with angiotensin-converting enzyme inhibitors and/or calcium channel blockers (2nd: 24-h BP < or = 130/80 mm Hg); 22 untreated (UT) HF+ and 18 UTHF- (2nd: 24-h BP >140 and/or 90 mm Hg); 18 normotensives F+ and 15 normotensives F-. The parameters evaluated were as follows: glucose, insulin, and C-peptide (Cp) response to an oral glucose load. Glucose was normal in all of the subjects, similar among the 6 groups, and unchanged at the 2nd evaluation. At the basal evaluation insulin and Cp were higher and the metabolic clearance rate (MCR) of glucose was lower in the three F+ groups compared with the corresponding F- groups. In the 2nd evaluation insulin and Cp were reduced and the MCR of glucose increased in THF-, whereas all metabolic parameters were unchanged in THF+; in both UT hypertensive groups insulin and Cp increased and the MCR of glucose decreased, more so in F+ than in F-; in normotensive groups metabolic parameters did not change. A familial predisposition to hypertension influences insulin sensitivity changes during successful antihypertensive therapy, with an improvement in insulin sensitivity in F- and no changes in F+. A persistently high BP has a negative influence on insulin sensitivity in F+ and F-; this influence is greater when high BP is associated with a familial predisposition to hypertension.

Insulin action and secretion in hypertension in the absence of metabolic syndrome: model-based assessment from oral glucose tolerance test

“…An association among insulin resistance (decreased sensitivity or responsiveness to the metabolic actions of insulin), hyperinsulinemia, and hypertension is generally recognized [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Demonstration that essential hypertension is an insulin-resistant state in its own right implied its involvement in the insulin resistance syndrome, later transmuted into the metabolic syndrome (MS) [1,2,17,18].…”

Insulin resistance in hypertension quantified by oral glucose tolerance test: comparison of methods

“…The insulin-resistant state in hypertension is a timehonored notion [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. Quantification of insulin sensitivity by well-accepted techniques, such as the euglycemichyperinsulinemic clamp and the minimal model analysis of FSIGTT data, in groups of nonobese and nondiabetic hypertensive patients, compared with groups of control subjects matched for age and BMI, showed significant reductions in hypertension ranging from 26% to 70% [1,7,8,14].…”

“…Knowledge of the etiology of insulin resistance and its link with hypertension, however, is far from complete [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. An improvement of knowledge can be determined by clinical applications of methods that allow quantification of indexes of insulin sensitivity in hypertensive patients to be compared with normotensive subjects.…”