Increased lipoprotein(a) in metabolic syndrome: is it a contributing factor to premature atherosclerosis?

It is well known that patients with metabolic syndrome (MS) have a greater risk of developing coronary artery disease (CAD). However, the association of novel coronary risk factors with MS has not been well established. In this study, we sought to investigate the association of lipoprotein (a) [Lp(a)], homocysteine (Hcy), uric acid, and C-reactive protein (CRP) levels with MS.

We enrolled 355 consecutive patients from our outpatient cardiology clinic into this cross-sectional, controlled study-186 with MS and 169 without MS, according to the Adult Treatment Panel III criteria. Serum Hcy, Lp(a), uric acid, and CRP levels were determined and compared between the groups.

The groups were homogenous with regard to age, sex, and other demographic variables (all p>0.05). As expected, the prevalence of hypertension (85.4% vs 55.6%, p<0.001) and dyslipidemia (78.3% vs 62.6%, p<0.05) were higher in patients in the MS group. Patients were comparable with respect to smoking (28.4% vs 24.8%, p =0.4) and family history of CAD (46.1% vs 40.8%, p=0.3). Patients with MS had significantly higher Lp(a) levels [29.2 (13.4-45.7) vs 16.2 (9.5-26.2) mg/dL; p<0.0001] compared with controls, whereas Hcy (12.2+/-4.8 vs 12.3+/-4.9 micromol/L; P=0.8), uric acid (5.7+/-1.6 vs 5.3+/-1.3 mg/dL; p=0.08), and CRP levels [6.0 (3.7-9.3) vs 5.1 (3.2-7.6) mg/L; p=0.07] were similar.

Patients with MS seems to have increased serum levels of Lp(a), which might contribute to the premature atherosclerosis observed in these patients. Further research is needed to better clarify this issue.