Patients with advanced chronic kidney disease (CKD) who experience greater fluctuation in their plasma potassium levels have a higher risk of dying once they transition to dialysis, a new study finds.
Investigators identified 34,167 mostly male US veterans with advanced CKD and calculated their individual plasma potassium variability based on measurements taken within the 3-year prelude to dialysis initiation. Potassium variability was categorized into quartiles: less than 0.31, 0.31 and higher but less than 0.41, 0.41 and higher but less than 0.52, and 0.52 mEq/L or more
In adjusted analyses, the risk for all-cause mortality within 6 months of starting dialysis was a significant 9% and 14% higher among patients in the third and fourth quartiles of plasma potassium variability, respectively, compared with the bottom quartile, Csaba P. Kovesdy, MD, of the Memphis VA Medical Center in Memphis, Tennessee, and colleagues reported in Kidney International Reports. The risk for cardiovascular mortality was not increased, however. The team adjusted the multivariable Cox and Fine-Gray competing risk regression models for estimated glomerular filtration rate, smoking status, comorbidities such as diabetes, hypertension, and heart failure, hospitalization stay, body mass index, vascular access type, medications such as renin angiotensin system inhibitors and diuretics, and other factors.
Previous studies in peritoneal dialysis patients have found a higher risk for all-cause and cardiovascular mortality with higher potassium variability, the investigators noted.
According to Dr Kovesdy’s team, “it is possible that the higher [potassium] variability detected during the evaluation period in our study is an early manifestation of subsequent dyskalemic events, which could potentially be prevented with early interventions.”
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Dashputre AA, Potukuchi PK, Sumida K, et al. Predialysis potassium variability and postdialysis mortality in patients with advanced CKD. Published online December 3, 2020. Kidney Int Rep. doi:10.1016/j.ekir.2020.11.022