Lipoprotein (a), hypertension, and cardiovascular outcomes: a prospective study of patients with stable coronary artery disease.

Abstract

Although emerging data suggest that circulating lipoprotein (a) [Lp (a)] could predict cardiovascular events (CVEs) in patients with cardiovascular disease, no study is currently available regarding the prognostic linkage of Lp (a) and hypertension in patients with coronary artery disease (CAD). This study sought to evaluate the association of Lp (a), hypertension and cardiovascular outcomes in patients with stable CAD. A total of 8668 patients with stable CAD were consecutively enrolled. Baseline Lp (a) concentrations were measured. All subjects were categorized according to Lp (a) levels of <10 (low), 10-30 (medium) and ≥30 mg/dL (high) and were further stratified by hypertension status. They were regularly followed-up for the occurrence of cardiovascular death, nonfatal myocardial infarction, and stroke. Over an average of 54.81 ± 18.60 months of follow-up, 584 (6.7%) CVEs occurred. Kaplan-Meier and multivariate Cox regression analyses showed that elevated Lp (a) levels had a significant association with CVEs in hypertensive patients, regardless of the control status of blood pressure, but not in normotensive subjects. Moreover, when analyzed by subgroups according to both Lp (a) category and hypertension status, the risk of CVEs was only significantly elevated in the high Lp (a) plus hypertension group compared with the reference group with low Lp (a) levels and normotension (hazard ratio: 1.80, 95% confidence interval: 1.11-2.91). Elevated Lp (a) was associated with an increased risk of CVEs in stable CAD patients with hypertension. Moreover, the coexistence of high Lp (a) concentrations and hypertension greatly worsened the clinical prognosis in patients with CAD, which may suggest a prognostic correlation between Lp (a) and hypertension.