Increased homocysteine and lipoprotein(a) levels highlight systemic atherosclerotic burden in patients with a history of acute coronary syndromes

Abstract

Background: Strong evidence supports an association between high levels of homocysteine (Hcy) and lipoprotein(a) [Lp(a)] and an increased rate of ischemic vascular events.

Methods: The study population comprised 162 patients (50 women [30.9%]; age, 66.71 ± 12.76 years) having a history of acute coronary syndrome within 1 year who underwent fasting blood sampling, measurement of intima-media thickness and pulse wave velocity at the common carotid and femoral arteries by Doppler ultrasound, and ankle-brachial index measurement. Cutoff values were considered 0.9 mm and 1.2 mm for carotid and femoral intima-media thickness, respectively; 12 m/s for pulse wave velocity; and <0.9 for ankle-brachial index. We included hypertension, dyslipidemia, diabetes, overweight/obesity, smoking, and family history of cardiovascular disease in the count of traditional risk factors (CRFs). Adding Hcy ≥15 μmol/L and Lp(a) ≥500 mg/L to CRFs, we obtained a new score, named TOTAL.

Results: On univariate analysis, Hcy and Lp(a) were significantly associated with presence of atherosclerotic extracoronary lesions (for Hcy: β = .934; standard error = 0.178; P < .0001; for Lp(a): β = .961; standard error = 0.177; P < .0001) and compliance alterations (for Hcy: odds ratio, 13.3; 95% confidence interval, 3.9-45.3; P < .0001; for Lp(a): odds ratio, 14.6; 95% confidence interval, 5.69-37.62; P < .0001). On multivariate analysis, Lp(a) and Hcy were significantly associated with extracoronary atherosclerosis, even after correction for CRFs. The area under the curve of the TOTAL score for both atherosclerosis and vascular compliance alterations was significantly higher than the area under the curve of traditional CRFs plus only Hcy ≥15 μmol/L or plus Lp(a) ≥500 mg/L, separately added.

Conclusions: The addition of evaluation of Hcy ≥15 μmol/L and Lp(a) ≥500 mg/L to the traditional CRF count does improve detection of systemic atherosclerotic burden of patients with acute coronary syndrome and can offer a new opportunity to optimize secondary prevention.