Kidney Disease Linked to Low Magnesium
Highest vs. lowest quartile of serum magnesium associated with a 58% increased CKD risk.
Low serum magnesium levels are associated with an elevated the risk of developing kidney disease, according to a new study.
Adrienne Tin, MD, of Johns Hopkins University in Baltimore, and colleagues studied 13,226 individuals aged 45-65 years participating in the Atherosclerosis Risk in Communities study. Subjects had baseline estimated glomerular filtration rates of 60 mL/min/1.73 m2 or higher in 1987–1989 and were followed through 2010. During a median follow-up of 21 years, chronic kidney disease (CKD) developed in 1,965 subjects and end-stage renal disease (ESRD) developed in 208.
With respect to CKD, those in the 1st quartile of serum magnesium (0.25-0.70 mmol/L) had a 1.58 increased risk compared with individuals in the 4th quartile (0.90–1.15 mmol/L), in a fully adjusted model, Dr. Tin's group reported online ahead of print in Kidney International. For ESRD, individuals in the 1st quartile had a 2.39 times increased risk compared with those in 3rd and 4th quartiles combined (0.85–1.15 mmol/L).
The researchers explained that the 3rd and 4th quartiles were combined as the reference group to ensure an adequate number of subjects in each subgroup (such as by diabetes status and diuretic use) in multivariate analysis.
“Further research is required to determine whether low total serum magnesium is itself nephrotoxic,” the authors concluded. “If so, our findings suggest that magnesium levels may be a novel therapeutic target for the prevention of CKD.”
Previous studies have found associations between low magnesium and kidney function decline in CKD patients and diabetics, as well as decreased allograft survival in kidney transplant recipients and mortality in hemodialysis patients, the researchers noted. It remains unclear, however, whether low serum magnesium is a cause or consequence of CKD risk factors or treatment or both.