Dietary and serum magnesium levels in patients with acute myocardial infarction, coronary artery disease and noncardiac diagnoses.

OBJECTIVE

To study the relation of dietary and serum levels of magnesium (Mg) in acute myocardial infarction (AMI) and its complications in relation to noncardiac diagnoses.

METHODOLOGY: Case control study in a primary and secondary care center for AMI patients. The study included 460 subjects with definite AMI (n = 335, group A), possible AMI (n = 64, group B), unstable angina (n = 19, group C) and controls with noncardiac chest pain (n = 42, group D). Demographic variables, dietary intake, and clinical and biochemical data were compared. Mean age, sex, body weight, and body mass index were comparable in all the groups.

RESULTS

Dietary fat and cholesterol intakes were significantly higher and carbohydrate intakes were lower in group A, B and C patients with coronary artery disease compared to control group D. Dietary consumption of Mg was comparable in all groups; however, in 85 patients in group A (272.5 mg/day) and 17 in group B (280.4 mg/day) in whom ventricular arrhythmias were present, Mg intake was relatively lower compared to control group D (316.6 mg/day). Serum Mg levels in group A (1.66 mEq/L), B (1.65 mEq/L), and C (1.66 mEq/L) were within normal (1.74 mEq/L) limits, but were significantly lower than in control group D.

CONCLUSIONS

Lower serum Mg in group A, B and C patients was attributed to increased demand during AMI, although in patients with complications (ventricular arrhythmias), Mg deficiency may in part result from relatively lower Mg intake, a hypothesis which requires further study.