Related Experiment Videos
Clustering of cardiovascular risk factors in confirmed prehypertensive individuals
S M Haffner1, E Ferrannini, H P Hazuda
1Department of Medicine, University of Texas Health Science Center, San Antonio 78284-7873.
Insights
Cardiovascular risk factors like high triglycerides and low HDL cholesterol appear before hypertension develops. These atherogenic changes may precede the onset of high blood pressure.
Area of Science:
- Cardiovascular disease
- Metabolic syndrome
- Hypertension research
Background:
- Hypertension is often associated with atherogenic lipoprotein patterns, hyperinsulinemia, and impaired glucose tolerance.
- These metabolic abnormalities may stem from antihypertensive medications or the hypertensive state itself.
Purpose of the Study:
- To investigate the cardiovascular risk factor profile in individuals who developed hypertension during an 8-year follow-up.
- To determine if atherogenic changes precede the development of hypertension.
Main Methods:
- Analysis of 1,440 initially normotensive subjects from the San Antonio Heart Study over 8 years.
- Comparison of baseline cardiovascular risk factors between subjects who developed hypertension and those who remained normotensive.
Main Results:
- Prehypertensive individuals exhibited higher baseline blood pressure, lipids (total and LDL cholesterol, triglycerides), glucose, and insulin levels.
- Lower high-density lipoprotein cholesterol and higher body mass index were observed in those who later developed hypertension.
- Elevated baseline triglycerides and blood pressure, and lower HDL cholesterol were significant predictors of future hypertension.
Conclusions:
- The study suggests that a cluster of atherogenic changes, including lipid and glucose metabolism abnormalities, precede the development of hypertension.
- These findings indicate that cardiovascular risk factors associated with hypertension may originate before blood pressure elevation.
Abstract:
Numerous studies have indicated that hypertensive subjects have an atherogenic lipoprotein pattern, hyperinsulinemia, and impaired glucose tolerance relative to normotensive individuals. These abnormalities could be due to adverse effects of certain antihypertensive agents, to pathophysiological concomitants of the hypertensive state itself, or to both. In this report, we describe the cardiovascular risk factor profile of 1,440 subjects who were normotensive and were not taking any antihypertensive medications when first examined and who subsequently participated in the 8-year follow-up of the San Antonio Heart Study. Hypertension developed in 130 subjects during the follow-up period. At baseline these prehypertensive individuals had significantly higher levels of blood pressure, fasting total and low density lipoprotein cholesterol, triglyceride, glucose, and insulin, and 2-hour glucose than those who remained free of hypertension. In addition, they had higher body mass indexes, a less favorable body fat distribution, and lower levels of high density lipoprotein cholesterol. In multiple linear regression analyses, baseline levels of triglyceride and blood pressure remained significantly higher and high density lipoprotein cholesterol remained significantly lower in the subjects who later converted to hypertension than in those who remained normotensive. Although baseline insulin levels were also higher in the prehypertensive subjects, this difference was not statistically significant. In nonobese subjects, however, those with high baseline insulin concentrations had an increased incidence of hypertension compared with those with low insulin concentrations. The present results suggest that the cluster of atherogenic changes associated with hypertension actually precede the development of the hypertensive state.