Objective: To investigate whether insulin resistance is the common route for hereditary and environmental factors to cause hypertension.
Methods: 93 hypertensives with family history of hypertension, 94 hypertensives without family history of hypertension and 99 normal tensives without family history of hypertension as well as their spouse, and one child in each family were enrolled in the present study. Insulin sensitivity was calculated from fasting plasma glucose (FPG) and insulin (FINS) with the formula insulin sensitivity index (ISI) = 1/(FPG x FINS) and insulin resistance index (Homa-IR) = (FPG x FINS)/22.5. The contribution of insulin resistance to blood pressure elevation was investigated by multivariate regression analysis.
Results: Subjects with essential hypertension, regardless of the presence or absence of family history of hypertension, were more insulin resistant. Multivariate regression analysis demonstrated that insulin resistance contributed to 17% of mean blood pressure (MBP) elevation, whereas taken FPG + total cholesterol (TC) + high density lipoprotein (HDL) together it explained only 9% of MBP changes in the indicator group. When family history of hypertension was included as a independent variable in the analysis, it became the most important factor instead of insulin resistance in the model and contributed to 30% of the changes of MBP, while contribution of insulin resistance was significantly reduced as to explain only 7% of the changes of MBP.
Conclusions: Insulin resistance is a common route for hereditary and environmental factors to induce hypertension. It is suggested that improving insulin sensitivity may play an important role in the management of essential hypertension.