Relevance of post-methionine homocysteine and lipoprotein (a) in evaluating the cardiovascular risk in young CAD patients.

BACKGROUND

Aims of our study were to evaluate the prevalence of high lipoprotein (a) [Lp(a)] and homocysteine levels - both in the fasting state (FHcy) and post-methionine (PMHcy) - in young coronary artery disease (CAD) patients, and to investigate the role of genetic and environmental factors for hyperhomocysteinaemia.

MATERIALS AND METHODS

We studied 140 patients with angiographically documented CAD (24 women </= 55 years and 116 men </= 50 years) and 140 healthy subjects as controls.

RESULTS

Both FHcy [13.2 (5.4-45.8) vs. 9.0 (5.1-24) micromol L(-1)); P < 0.0001] and PMHcy [(39.4 (9.0-66.4) vs. 25.2 (16.4-33.9); P < 0.0001] were significantly higher in patients than in controls. Lp(a) levels were significantly higher in patients than in controls (200 (3-1486) mg L(-1) vs. 97 (10-412) mg L(-1); P < 0.0001). At the multivariate analysis, adjusted for the classical cardiovascular risk factors and creatinine levels, the OR (95% CI) for CAD at young age significantly increased in the fourth quartile of the distribution of FHcy, PMHcy and Lp(a) levels [FHcy: 14.9 (4.1-58), P < 0.0001; PMHcy: 19.2 (4.0-86.3); P < 0.0001; Lp(a): 19.6 (4.7-78.6): < 0.0001]. Vitamin deficiencies were detected in 28/140 (20%) patients. The prevalence of the homozygous C677T (+/+) methylenetetrahydrofolatereductase genotype was higher, but not significantly different, in patients (22.8%) than in controls (18.6%). The allele frequency of the 844ins68 insertion variant in the cystathionine beta-synthase gene was 0.08 in the control group and 0.06 in the patient group.

CONCLUSIONS

Results of the present study indicate the usefulness of including fasting and post-methionine Hcy, and Lp(a) determination in the diagnostic panels of young CAD patients, in order to obtain a better assessment of their cardiovascular risk profile.