Effective blood pressure treatment improves LDL‐cholesterol susceptibility to oxidation in patients with essential hypertension

Abstract

Quin Ä ones-Galvan A, Pucciarelli A, Fratta-Pasini A, ). Effective blood pressure treatment improves LDL-cholestrol susceptibility to oxidation in patients with essential hypertension. J Intern Med 2001; 250: 322±326.Objectives. LDL-cholesterol particles from hypertensive patients exhibit enhanced susceptibility to in vitro oxidation, an abnormality thought to increase cardiovascular risk. We tested whether blood pressure (BP) normalization can reverse this abnormality. Design. Double-blind, randomized pharmacological intervention trial. Setting. Clinical research centre. Subjects. A total of 29 nondiabetic, normolipidaemic patients with essential hypertension (BP 151 3/99 1 mmHg) and 11 normotensive controls (BP 125 3/85 1 mmHg) matched for gender, age, obesity, glucose tolerance and lipid pro®le.Intervention. Anti-hypertensive treatment for 3 months with a calcium-antagonist in randomized combination with either an ACE inhibitor or a b-blocker.Main outcome measures. Lag phase of copperinduced LDL oxidation, cell-mediated (human umbilical vein endothelium) generation of malondialdehyde (MDA) by LDL and vitamin E content in LDL.Results. At baseline in hypertensives versus controls, lag phase was shorter (89 3 vs. 107 6 min, P < 0.04), MDA generation was higher (5.8 0.1 vs. 5.1 0.2 nmol L ±1 , P 0.002), and vitamin E was reduced (6.40 0.05 vs. 6.67 0.11 lg mg ±1 , P 0.03). At 3 months, BP was normalized (124 3/81 1, P < 0.0001 vs. baseline, P ns versus controls), lag phase was prolonged (to 98 3 min, P 0.0005), MDA generation was reduced (5.6 0.1 nmol L ±1 , P = 0.001), and vitamin E was increased (6.53 0.05 lg mg ±1 , P 0.003), with no signi®cant differences between the randomized groups. Conclusions. In nondiabetic, nonobese, normolipidaemic patients with essential hypertension, LDL susceptibility to copper-and cell-mediated oxidation is increased. BP normalization is associated with a signi®cant improvement, but not a full reversal, of this abnormality.