Risk factors for the development of hypertension: a 10-year longitudinal study in middle-aged men.

A group of middle-aged men (n = 2322) were examined at a health screening which included an intravenous glucose tolerance test (IVGTT) with insulin determinations, and were then re-examined approximately 10 years later. At the first survey, 19.6% of the participants had hypertension, defined as diastolic blood pressure greater than or equal to 95 mmHg or were receiving drug treatment for hypertension. At follow-up survey, the corresponding figure was 34.7%. Baseline blood pressures were the strongest predictors of future development of hypertension. In the absence of baseline blood pressures, fasting and late insulin levels at IVGTT, difference in body mass index between the surveys and heredity for hypertension were significant risk factors for hypertension. When a difference in diastolic blood pressure was used as an independent variable, the only significant risk factor was the difference in body mass index. Thus, insulin resistance (as reflected by fasting, late insulin levels and body mass index) seems to be related to the development of hypertension.