Sustained Normokalemia to Enable RAAS Inhibition Beneficial in CKD
New model predicts that maintenance of normal potassium levels in CKD patients to optimize use of renin-angiotensin-aldosterone inhibitors can delay progression to ESRD and prolong survival.
Maintaining normal potassium levels in patients with chronic kidney disease (CKD) so they can receive optimal therapy with renin-angiotensin-aldosterone system inhibitors (RAASi) can delay progression to end-stage renal disease and prolong survival, according to investigators.
RAASi therapy often is suboptimal or discontinued in patients with CKD because of concerns about an increased risk of hyperkalemia, an electrolyte abnormality for which CKD patients already are at risk because of impaired renal function, Marc Evans, MD, of Llandough Hospital in Cardiff, UK, and colleagues noted in a paper published in BMC Nephrology. Withholding RAASi therapy may lead to incremental health care costs associated with poor outcomes, such as earlier onset of ESRD, hospitalizations related to cardiovascular events, and cardiovascular mortality, they said.
“Novel strategies that safely and effectively manage serum potassium levels, whilst allowing the optimal delivery of established renoprotective therapies, may therefore have significant potential to improve long-term outcomes in the CKD population,” they wrote.
Dr Evans and his co-authors developed a model to qualify the health and economic benefits of maintaining normokalemia and enabling RAASi use in patients with CKD. Natural progression of CKD was modelled via a gradual decline in estimated glomerular filtration rate (eGFR), where RAASi use impacted the rate of decline. Simulated patients progressed sequentially through CKD stages until ESRD onset. Based on associations established in previous published studies, the investigators modelled rates of clinical outcomes (cardiovascular events, hospitalizations, and death) prior to renal replacement therapy in relation to various serum potassium levels at different eGFR values and/or RAASi use.
According to the model, sustained normokalemia and continued RAASi treatment predicted a 2.36-year extension of life expectancy and, among patients who progressed to ESRD, a mean 5.4-year delay in ESRD onset, compared with not using RAASi therapy as a way to prevent hyperkalemia. Sustained normokalemia and continued RAASi treatment also were associated with improved quality of life and cost savings.
“The model developed in this study has the potential to inform broad decision making on interventions for hyperkalaemia, as cost is an increasingly important consideration,” the authors wrote.
Evans M, Palaka E, Furuland H, et al. The value of maintaining normokalaemia and enabling RAASi therapy in chronic kidney disease. BMC Nephrol. 2019;20:31.