OBJECTIVES: The risk of hyperkalemia (HK) is a barrier to renin-angiotensin-aldosterone system inhibitor (RAASi) therapy in chronic kidney disease (CKD) and/or heart failure (HF). Novel potassium-binding treatments may facilitate the maintenance of RAASi therapy. This study assesses healthcare costs and all-cause mortality after an event of HK and a reduction of RAASi therapy in Sweden.

METHODS: Data from national health registers and electronic medical records were analyzed. The study sample included patients aged ≥18 years with HF and/or CKD, and RAASi use at baseline. Patients were categorized as having maintained or reduced (down-titrated or discontinued) RAASi treatment after their HK episode, and 1:1 propensity score (PS) matching was applied to compare the patient groups.

RESULTS: Out of 20,824 patients, 41.9% (n=8716) reduced their RAASi treatment after the index HK episode. Following matching, 6998 patients remained in each group (maintained vs. reduced RAASi) and were compared. During the six months following the HK event, outpatient visits per person-year increased by 26.6% among patients who reduced their RAASi treatment and 12.4% among those who maintained it compared to 6 months before the HK event. Similarly, inpatient bed-days showed an increase of 117.2% in those who reduced RAASi vs. 62.1% in those who maintained. In addition, patients who reduced RAASi were on average alive 121.5 (SD 75.0) days outside the hospital, compared to 154.0 (SD 51.3) in those who maintained RAASi. Healthcare costs, and the burden of incremental all-cause mortality, will be presented.

CONCLUSIONS: Reducing RAASi therapy after an event of HK is associated with increased hospitalization costs and an increase in the risk of all-cause mortality. These findings emphasize the importance of carefully considering the implications of reducing or discontinuing RAASi treatment after a HK event.