Homocysteine is associated with both myocardial infarction and arterial wall inflammation. To establish whether homocysteine is associated with myocardial infarction after adjusting for age, sex, the major cardiovascular risk factors and inflammatory risk predictors (fibrinogen, C-reactive protein and interleukin-6). A case-control study, using 364 myocardial infarction cases drawn from the north Glasgow MONICA study, 3-9 months after their event, and 383 controls drawn from the general population of the same geographical area. The odds ratio for myocardial infarction increased progressively across the four quarters of the homocysteine distribution, after adjusting for only age and sex or for the full adjustment (age, sex, smoking, systolic blood pressure, total cholesterol, fibrinogen, C-reactive protein and interleukin-6). The odds ratios produced by the two adjustments were similar. Comparing the top quarter with the bottom quarter of homocysteine, the odds ratio was 2.21 (95% confidence interval: 1.30-3.76) after the full adjustment. The odds ratio for a 5 micromol/l increase in homocysteine was 1.12 (95% confidence interval: 1.01-1.24) after the full adjustment.
Conclusion: This study suggests that homocysteine has an effect on cardiovascular risk over and above that of inflammatory markers and the major cardiovascular risk factors.