Researchers in China and Japan, led by Jinping Li, MD, conducted an analysis of patients with non-dialysis dependent chronic kidney disease (CKD) stages 3 to 5 to examine the effect of serum potassium level and hyperkalemia on the decline in renal function. Results were reported in the Chinese Medical Journal [DOI: 10.3760/cma.j.cn112137-20201218-03394].
The patients were divided into three groups: (1) stable; (2) slow progressing; and (3) fast progressing. The correlations between baseline serum potassium and time-average serum potassium levels and CKD progression were evaluated using multivariate logistic regression analysis.
The analysis included 343 patients treated at Tianjin First Central Hospital, China, and 669 patients treated at Teikyo University Medical School Affiliated Hospital of Japan, Tokyo (total=1012). Mean age was 61 years and 62.7% (n=635) were male. The average decline in estimated glomerular filtration rate (eGFR) was 4.0% per year. The study cohort included 337 patients in the stable group, 337 in the slow progressing group, and 338 in the fast progressing group. In the rapidly progressing group, 83 patients (24.6%) had baseline hyperkalemia, defined as serum potassium ≥5.0 mmol/L, and 118 patients (34.9%) had an average serum potassium of ≥5.0 mmol/L; both measurements were higher than in patients in the stable group.
Results of multivariate logistic regression demonstrated that baseline serum potassium and time average serum potassium were correlated with rapid progression of CKD (odds ratios, 1.843; 95% confidence interval [CI], 1.051-3.234 and 2.495; 95% CI, 1.040-5.987, respectively). Time average serum potassium ≥5.0 mmol/L was an independent predictor of rapid progression of CKD.
“Controlling the mean serum potassium level of <5.0 mmol/L in CKD stage 3-5 patients without dialysis during the follow-up period may reduce the risk of rapid renal function progression,” the researchers said.