Anti-phospholipid antibodies and carotid-artery intima-media thickness in young survivors of myocardial infarction.

BACKGROUND

Not all coronary events occur in young individuals with traditional risk factors. In recent years some authors have observed increased prevalence of elevated anti-phospholipid (aPL) antibodies in young patients with myocardial infarction. Also, thickening of the combined arterial intima-media thickness (IMT) of superficial vessels has been identified as an independent risk factor for both stroke and heart attack. The objective of our study was to assess possible association between aPL antibodies and carotid IM thickening in young survivors of myocardial

METHODS

In a case control study we determined IgG and IgM antiphospholipid antibodies by enzyme-immunoassay, and IMT by ultrasonography in 50 male survivors of myocardial infarction under the age of 50, and compared them to 50 healthy controls.

RESULTS

Elevated aPL antibody levels (IgG>10 GPL; IgM>20MPL) were detected in 12 of 50 patients (24%) with MI and in 3 of 50 controls (6%). The mean level of aPL antibodies was significantly higher in the patients than in the controls (IgG 9.15+/-3.53 vs 7.69+/-2.98 GMP, p=0.04 and IgM 18.46+/-7.61 vs 12.14+/-5.05 MPL, p<0.01). Patients with MI had a significantly greater IMT than healthy controls (0.9 mm vs 0.6 mm; p<0.01). There was a correlation between aPL and IM thickening (r=0.31; p=0.01). Among coronary risk factors only hypertension (r=0.28; p=0.01) and smoking (r=0.41; p=0.01) showed a relationship with IMT.

CONCLUSIONS

The intima-media thickness of the carotid artery and elevated aPL antibodies are strongly associated with the risk of myocardial infarction in young patients.