RAAS inhibitor discontinuation more harmful than beneficial in hyperkalaemic CKD patients

Chronic kidney disease (CKD) patients with hyperkalaemia may fare better with maintaining than discontinuing treatment with a renin-angiotensin-aldosterone system (RAAS) inhibitor, as discontinuation poses risks of higher mortality and increased cardiovascular (CV) events, according to a study.

Researchers examined the medical records of 7,200 CKD patients in Manitoba and 71,290 CKD patients in Ontario, Canada, who had an episode of de novo RAAS inhibitor-related hyperkalaemia (serum potassium ≥5.5 mmol/L).

The respective mean potassium and mean estimated glomerular filtration rate were 5.8 mEq/L and 41 mL/min/1.73 m² in the Manitoba cohort, and 5.7 mEq/L and 41 mL/min/1.73 m² in the Ontario cohort.

RAAS inhibitor discontinuation was positively associated with the primary outcome of all-cause mortality. Cox proportional hazards analysis revealed that treatment discontinuation upped the risk of death by 32 percent in the Manitoba cohort (hazard ratio [HR], 1.32, 95 percent confidence interval [CI], 1.22–1.41) and by 47 percent in the Ontario cohort (HR, 1.47, 95 percent CI, 1.41–1.52).

Furthermore, cessation of RAAS inhibitor treatment contributed to increased risks of CV mortality (Manitoba cohort: HR, 1.28, 95 percent CI, 1.13–1.44; Ontario cohort: HR, 1.32, 95 percent CI, 1.25–1.39) and dialysis initiation (Manitoba cohort: HR, 1.65, 95 percent CI, 1.41–1.85; Ontario cohort: HR, 1.11, 95 percent CI, 1.08–1.16).