Ambulatory Treatments for RAAS Inhibitor-Related Hyperkalemia and the 1-Year Risk of Recurrence

Abstract

Background and objective: The optimal ambulatory management of renin-angiotensin-aldosterone system inhibitor (RAASi)-related hyperkalemia to reduce the risk of recurrence is unknown. We examined the risk of hyperkalemia recurrence on the basis of outpatient pharmacologic changes following an episode of RAASi-related hyperkalemia.

Design: We performed a population-based, retrospective cohort study of older adults (n=49,571; mean age 79 years) who developed hyperkalemia (potassium ≥5.3 mEq/L) while on a RAASi and were grouped as follows: no intervention, RAASi discontinuation, RAASi dose decrease, new diuretic, diuretic dose increase, or sodium polystyrene sulfonate within 30 days. The primary outcome was hyperkalemia recurrence, with secondary outcomes of cardiovascular events and all-cause mortality within 1 year.

Results: Among patients who received a pharmacologic intervention (23% of the cohort), RAASi discontinuation was the most commonly prescribed strategy (74%), followed by RAASi decrease (15%), diuretic increase (7%), new diuretic (3%), and sodium polystyrene sulfonate (1%). A total of 16,977 (34%) recurrent hyperkalemia events occurred within 1 year. Compared with no intervention (35%, referent), the cumulative incidence of recurrent hyperkalemia was lower with RAASi discontinuation (29%; hazard ratio, 0.82; 95% confidence interval, 0.78 to 0.85), whereas there was no difference with RAASi dose decrease (36%; hazard ratio, 0.94; 95% confidence interval, 0.86 to 1.02), new diuretic (32%; hazard ratio, 0.95; 95% confidence interval, 0.78 to 1.17), or diuretic increase (38%; hazard ratio, 0.99; 95% confidence interval, 0.87 to 1.12) and a higher incidence with sodium polystyrene sulfonate (55%; hazard ratio, 1.30; 95% confidence interval, 1.04 to 1.63). RAASi discontinuation was not associated with a higher risk of 1-year cardiovascular events (hazard ratio, 0.96; 95% confidence interval, 0.91 to 1.02) or all-cause mortality (hazard ratio, 1.05; 95% confidence interval, 0.96 to 1.15) compared with no intervention.

Conclusions: Among older adults with RAASi-related hyperkalemia, RAASi discontinuation is associated with the lowest risk of recurrent hyperkalemia, with no apparent increase in short-term risks for cardiovascular events or all-cause mortality.

Keywords: chronic kidney disease; clinical nephrology; electrolytes; epidemiology and outcomes; hyperkalemia; recurrence; renin; renin-angiotensin system.