Lower serum calcium levels, even within a normal physiologic range, are a significant risk factor for a rapid decline in estimated glomerular filtration rate (eGFR) among individuals in the general population without chronic kidney disease (CKD), according to a Japanese study.
The association is independent of previously reported metabolic risk factors for renal dysfunction, such as blood pressure, diabetes, and dyslipidemia.
Writing in Scientific Reports, investigators concluded that lower serum calcium levels can be a useful marker for predicting which individuals are at elevated risk for worsening renal function in ordinary clinical settings.
Satoru Mizushiri, MD, of Hirosaki University Graduate School of Medicine, Hirosaki, Japan, and colleagues studied 218 men and 380 women aged 40 years or older and who had an eGFR above 60 mL/min/1.73 m2.
Compared with individuals in the highest tertile of serum calcium level (above 9.6 mg/dL), those in the lowest tertile (less than 9.4 mg/dL) had 2.4-fold greater odds of a rapid decline in eGFR (a decline of at least 4.4 mL/min/1.73 m2). In addition, compared with a serum calcium level of 9.2 mg/dL or higher, those with a level below 9.2 mg/dL had 3.3-fold increased odds.
Mizushiri S, Daimon M, Murakami H, et al. Lower serum calcium levels are a risk factor for a decrease in eGFR in a general non-chronic kidney disease population. Sci Rep. 2018; 8(1):14213.