Serum cholesterol levels, blood pressure response to stress and incidence of stable hypertension in young subjects with high normal blood pressure.

RATIONALE

Elevated serum cholesterol levels are common in patients with high blood pressure (BP) and could contribute to the progression of the hypertensive disease.

OBJECTIVE

To determine whether serum cholesterol levels affect the BP response to mental stress (MA) and the development of stable hypertension in young subjects with high normal BP.

METHODS

Seventy young (age < 45 years) high normal BP subjects with elevated (> 200 mg/dl, n = 49; HC) or normal (< or = 199 mg/dl, n = 21; NC) serum cholesterol levels, and 20 normotensive normocholesterolaemic (serum cholesterol < 199 mg/dl; C) subjects undergoing standardized mental challenge (mental arithmetic) were followed up for 15 years according to a prospective, longitudinal, cohort study design conducted in an ambulatory setting. The main outcome measure was the evaluation of the 15-year incidence of stable hypertension (diastolic BP > 95 mmHg).

RESULTS

After adjustment for age, resting BP, family history of high BP and body mass index at the study entry, high normal BP subjects with HC showed an enhanced BP reactivity to stress and a higher 15-year incidence of stable hypertension compared to high normal BP and NC subjects [relative risk (RR) = 2.1; 95% confidence interval (CI) = 1.7-5.5, P < 0.001] and controls (RR = 3.1; 95% CI = 1.4-5.3, P < 0.001). In a multivariate analysis of data the presence of high cholesterol levels was an independent predictor for the development of hypertension.

CONCLUSION

These data suggest that subjects with high normal BP and elevated serum cholesterol might have an exaggerated cardiovascular response to stress and have an increased risk for stable hypertension that can be detected at young age.