PLASMA HOMOCYSTEINE LEVELS AND MORTALITY IN PATIENTS WITH CORONARY-ARTERY DISEASE

Background Elevated plasma homocysteine levels are a risk factor for c oronary heart disease, but the prognostic value of homocysteine levels in patients with established coronary artery disease has not been def ined. Methods We prospectively investigated the relation between plasm a total homocysteine levels and mortality among 587 patients with angi ographically confirmed coronary artery disease. At the time of angiogr aphy in 1991 or 1992, risk factors for coronary disease, including hom ocysteine levels, were evaluated. The majority of the patients subsequ ently underwent coronary-artery bypass grafting (318 patients) or perc utaneous transluminal coronary angioplasty (120 patients); the remaini ng 149 were treated medically. Results After a median follow-up of 4.6 years, 64 patients (10.9 percent) had died. We found a strong, graded relation between plasma homocysteine levels and overall mortality. Af ter four years, 3.8 percent of patients with homocysteine levels below 9 mu mol per liter had died, as compared with 24.7 percent of those w ith homocysteine levels of 15 mu mol per liter or higher. Homocysteine levels were only weakly related to the extent of coronary artery dise ase but were strongly related to the history with respect to myocardia l infarction, the left ventricular ejection fraction, and the serum cr eatinine level. The relation of homocysteine levels to mortality remai ned strong after adjustment for these and other potential confounders. In an analysis in which the patients with homocysteine levels below 9 mu mol per liter were used as the reference group, the mortality rati os were 1.9 for patients with homocysteine levels of 9.0 to 14.9 mu mo l per liter, 2.8 for those with levels of 15.0 to 19.9 mu mol per lite r, and 4.5 for those with levels of 20.0 mu mol per liter or higher (P for trend = 0.02). When death due to cardiovascular disease (which oc curred in 50 patients) was used as the end point in the analysis, the relation between homocysteine levels and mortality was slightly streng thened. Conclusions Plasma total homocysteine levels are a strong pred ictor of mortality in patients with angiographically confirmed coronar y artery disease. (C)1997, Massachusetts Medical Society.