Low serum magnesium tied to increased CAD risk

Low circulating magnesium (Mg) is associated with a higher risk of coronary artery disease (CAD) as compared to higher Mg, according to a study.

A total of 2,131 incident CAD cases were recorded over a median follow-up of 27 years. Low vs higher serum Mg correlated with higher CAD risk after adjusting for demographics, lifestyle factors and other CAD risk factors (Q1 vs Q5: hazard ratio [HR], 1.28, 95 percent confidence interval [CI], 1.11–1.47; p-linear trend<0.001).

This association was more evident among women (Q1 vs Q5: HR, 1.53, 95 percent CI, 1.22–1.92) than men (HR, 1.11, 95 percent CI, 0.92–1.34; p-interaction=0.05).

In the meta-analysis including five studies, the lowest vs highest circulating Mg category had a pooled relative risk of 1.18 (95 percent CI, 1.06–1.31; I², 22 percent; p-heterogeneity=0.27).

“Whether increasing Mg concentrations within healthy limits is a useful strategy for CAD prevention remains to be seen,” the authors said.

This study followed 14,446 participants (baseline mean age, 54 years; 57 percent women; 27 percent African American) from the Atherosclerosis Risk in Communities (ARIC) Study for incident CAD through 2017. CAD events were defined as myocardial infarction or CAD mortality.

Serum Mg was modeled as quintiles based on mean visit 1 (1987–1989) and visit 2 (1990–1992) concentrations. The authors used Cox regression models and also conducted a random-effects meta-analysis incorporating these contemporary ARIC findings.

“A previous ARIC Study article that evaluated the Mg–CAD association, based on 319 events occurring over 4–7 years, identified a sex interaction whereby the inverse Mg–CAD association was much stronger among women than men,” the authors noted. “More than 1,700 additional ARIC CAD events have since accrued.”