CHICAGO (FRONTLINE MEDICAL NEWS) – Low levels of serum magnesium were associated with increased all-cause mortality, whether or not patients had chronic kidney disease, in a single center, retrospective study of 3,551 people.

The association was independent of sociodemographic factors, comorbidities, and use of diuretics.

If causality is shown, “magnesium supplementation could be a simple therapy to lessen the chance of death in CKD patients,” study investigator Silvia Ferrè, PhD, University of Texas Southwestern, Dallas, said in an interview regarding the results of the Dallas Heart Study, which was presented at the annual meeting of the American Society of Nephrology.

This retrospective analysis involved 3,551 study participants in the Dallas Heart Study who had serum magnesium measured at their baseline visit. Of these, CKD did not develop in 3,245 subjects and did develop in 306 subjects. Both groups could be stratified according to low, medium, and high serum magnesium. In the non-CKD group, the low (736 subjects), medium (1,461), and high (1,048) tertiles of serum magnesium comprised. The respective numbers in the CKD group were 118, 109, and 79 subjects.

In both groups, the subjects with low serum magnesium were younger, more likely to be female, had a higher body mass index, and were more burdened by comorbidities including type 2 diabetes mellitus and hypertension. Subjects without CKD and low serum magnesium were significantly more likely to use diuretics. Diuretic use was comparable in subjects with CKD regardless of serum magnesium level.

Irrespective of CKD status, survival was significantly lower in subjects with low serum magnesium in the median 12.3-year follow-up compared to the other two serum magnesium tertiles (P less than 0.001 and P equal to 0.03, respectively). Following adjustment for age, gender, race/ethnicity, body mass index, phosphorus, calcium, bicarbonate, albumin, intact parathyroid hormone, total cholesterol, high-density lipoprotein, and use of diuretics and supplements, low serum magnesium was independently associated with all-cause death in subjects with CKD (Hazard Ratio, 1.92; 9%% Confidence Interval, 1.03 to 3.59; P equal to 0.04) and those without CKD (HR, 1.43; 1.43; 95% CI, 0.95 to 2.15; P equal to 0.09), when compared to high serum magnesium as the referent.

Dr. Ferrè said that screening for serum magnesium and supplementation with magnesium as part of routine blood testing might improve survival. Low magnesium level alsonhas been linked with osteoporosis, diabetes, and cardiovascular disease.

The Dallas Heart Study was a multiethnic, population-based study involving 6,101 adults residing in Dallas County. The study, which ran from 2000 to the end of 2011, was designed to explore the early detection of cardiovascular disease and the social, behavioral, and environmental factors associated with risk, with the goal of interventions that can be provided at the community level.

The study sponsor was University of Texas Southwestern Medical Center. The study was funded by the National Institutes of Health and the Donald W. Reynolds Foundation. Dr. Ferrè reported having no financial disclosures.