Risk of Myocardial Infarction in Relation to Plasma Levels of Homocysteine and Inflammation-Sensitive Proteins: A Long-Term Nested Case-Control Study

Abstract

Several studies have found that the homocysteine plasma level is associated with cardiovas cular disease. The authors previously described a relationship between concentrations of fibrinogen and other inflammation-sensitive plasma proteins, namely, α₁-antitrypsin, cerulo plasmin, haptoglobin, and orosomucoid (α ₁-acid glucoprotein) and the incidence of myocardial infarction (MI). Whether levels of these proteins are related to homocysteine has not been clarified. The aim of this study was to investigate whether a supposed relationship between homocysteine in plasma and the occurrence of MI is modified by these inflammation-sensitive proteins. A nested case-control study was designed, comprising 241 cases of MI, with a mean age of 48 years at baseline, and 241 controls matched for age, month of examination, and duration of follow-up. The mean homocysteine concentration did not differ between cases and controls and there was no association between the baseline homocysteine level and the time lapse before the occurrence of the MI. For the cases, there was no correlation between homo cysteine and any of the measured proteins, but for the controls, homocysteine was weakly but significantly negatively correlated to haptoglobin and ceruloplasmin and slightly positively correlated to albumin. For the separated groups of cases and controls there was no associa tion between the number of inflammation-sensitive proteins in the top quartiles and homo cysteine concentration. In this population-based, prospective cohort study the occurrence of MI had no relationship to homocysteine baseline plasma level. Furthermore, there was no strong association between homocysteine and the concentrations of any of these inflamma tion-sensitive proteins.