Different metabolic predictors of white-coat and sustained hypertension over a 20-year follow-up period: a population-based study of elderly men.

Abstract

The clinical significance of white-coat hypertension is still unclear. Moreover, no study has examined metabolic predictors of white-coat versus sustained hypertension. We investigated men (n=602) in a longitudinal population-based cohort who at age 70 years were identified as normotensive, white-coat hypertensive (office blood pressure [BP] > or =140/90 and daytime ambulatory BP <135/85 mm Hg), and sustained hypertensive (office BP > or =140/90 and daytime ambulatory BP > or =135/85 mm Hg). At baseline, when the subjects were aged 50 years, blood glucose, insulin, lipids, and fatty acid composition of the serum cholesterol esters were analyzed. The investigations at age 70 years included determination of insulin sensitivity and target organ damage. At age 50 years, individuals who 20 years later were identified as white-coat hypertensive or sustained hypertensive showed significantly elevated BP, heart rate, and impaired glucose tolerance compared with normotensive subjects but white coat hypertensive subjects were leaner and had a more favorable serum cholesterol ester fatty acid profile than did sustained hypertensive subjects. At age 70 years, both white-coat and sustained hypertensive subjects showed an impaired insulin sensitivity, elevated blood glucose, and increased serum insulin and heart rate compared with normotensive subjects, but left ventricular mass and urinary albumin excretion were increased only in sustained hypertensive subjects. These findings indicate that although metabolic abnormalities and elevated heart rate were consistent over time in both hypertensive groups, a lower body mass index and more favorable dietary fat composition predicted the development of white-coat as opposed to sustained hypertension over 20 years.