Association between total homocyst(e)ine and the likelihood for a history of acute myocardial infarction by race and ethnicity: Results from the Third National Health and Nutrition Examination Survey

Background Few studies examining the association between total homocyst(e)ine and coronary heart disease have included blacks or Hispanics. Methods Data from the third National Health and Nutrition Examination Survey (3173 patients), a nationally representative survey of US adults, were used to examine the relation between total homocyst(e)ine and an electrocardiogram or a physician's diagnosis of acute myocardial infarction (259 patients) among whites, blacks, and Mexican Americans greater than or equal to 40 years aid. Results Vitamin B-12 and serum folate concentrations were significantly lower among persons with a total homocyst(e)ine concentration greater than or equal to 15 mu mol/L than among those with a total homocyst(e)ine concentration less than or equal to 10 mu mol/L. Persons with a total homocyst(e)ine concentration greater than or equal to 15 mu mol/L were also older and more likely to be hypertensive, have a higher cholesterol concentration, and smoke. Compared with persons with a total homocyst(e)ine concentration less than or equal to 10 mu mol/L, persons with a concentration greater than or equal to 15 mu mol/L had an odds ratio (OR) for myocardial infarction of 1.8 (95% confidence interval [CI], 1.2-2.9) after adjustment for cardiovascular disease risk factors. Similar associations were noted among whites (OR 1.8, 95% CI, 1.1-3.1) and blacks (OR 1.9, 95% CI, 0.8-4.2); a more modest association was noted among Mexican Americans (OR 1.2, 95% CI, 0.3-5.0). The association between total homocyst(e)ine and myocardial infarction was also more pronounced in persons without hypertension or diabetes. Conclusions Almost a 2-fold increased likelihood of myocardial infarction among persons with a total homocyst(e)ine concentration greater than or equal to 15 mu mol/L was noted in this nationally representative survey. The magnitude of the association did not differ by race or ethnicity.