Prognostic value of lipoprotein fractions in essential hypertension

Abstract

Background: To evaluate distribution and prognostic value of total cholesterol and lipoprotein fractions in essential hypertension.

Methods: In a prospective cohort study, 2649 initially untreated subjects with essential hypertension (aged 51, 46.5% women) were investigated at entry and followed for a mean of 5.6 years (range: 1-16).

Results: At entry, subjects with total cholesterol (TC) > or =240 mg/dl (> or =6.22 mmol/l) or high-density lipoprotein (HDL) cholesterol (HDL-C) <40 mg/dl (1.05 mmol/l) or low-density lipoprotein (LDL) cholesterol (LDL-C) > or =160 mg/dl (4.13 mmol/l) or TC/HDL-C ratio >6 were 47.7%. TC, HDL-C, LDL-C and triglycerides (TG) did not show any association with office or 24-h ambulatory blood pressure (BP). During follow-up there were 167 first cardiac events and 122 first cerebrovascular events. TC, HDL-C, LDL-C and TC/HDL-C ratio showed an association with cardiac events, but not with cerebrovascular events. TG did not show any association with cardiac or cerebrovascular events. After adjustment for age, sex, diabetes, smoking, left ventricular (LV) hypertrophy and 24-h pulse pressure, the hazard ratio for cardiac events was 1.83 (95% CI 1.23-2.71) in association with a TC > or =6.22 mmol/l, 2.23 with a HDL-C <1.05 mmol/l (95% CI 1.06-4.70), 2.83 with a LDL-C > or =4.91 mmol/l (95% CI 1.48-5.42) and 3.90 with a TC/HDL-C ratio >6.0 (95% CI 2.23-6.81). When forced in the same model, HDL-C and LDL-C showed an independent association with cardiac events.

Conclusions: Abnormalities of TC and lipoproteins are common in essential hypertension. HDL-C and LDL-C independently predict the risk of cardiac, but not cerebrovascular, events. Their predictive value is independent of several confounding factors including LV hypertrophy and ambulatory BP.