OBJECTIVES: Hyperkalemia (HK) refers to increased serum potassium concentration in the blood, with possible severe effects on health outcomes. The risk of HK is often prevalent in patients suffering from heart or chronic kidney diseases (CKD) and can be amplified by medications, e.g. inhibitors of the renin-angiotensin-aldosterone system (RAAS).

The aims of this study were to compare health-relevant outcomes and healthcare costs between HK patients and non-hyperkalemia patients in Germany.

METHODS: A retrospective, matched cohort analysis was conducted. Data from the InGef research database containing German claims of over 4 million covered lives were used. Patients were identified in 2015, with an individual pre- and post-index period (index: first observable HK diagnosis/treatment in 2015) of 4 quarters. Two HK cohorts, individuals with outpatient-treated and with chronic HK, were identified. Diagnosis code E87.5 and/or ATC code VA03AE01 identified HK. Individuals with chronic HK were required to have diagnoses and/or HK treatment in all quarters of the post-index period. An exact 1:1 matching to patients without hyperkalemia was performed for both HK-cohorts.

RESULTS: In total, 3,191 individuals with outpatient-treated HK and 1,664 individuals with chronic HK were matched 1:1 to their respective non-hyperkalemia cohort. Both hyperkalemia cohorts showed a significantly higher proportion of diabetes mellitus type 2 and heart failure in comparison to the matched non-hyperkalemia cohorts. A significantly increased healthcare utilization was observable in the number of hospitalizations for both HK cohorts. Healthcare costs for outpatient-treated and chronic HK patients versus non-hyperkalemia individuals were higher in terms of outpatient, inpatient, pharmaceuticals, and devices and aids costs as well as overall costs in the post-index period.

CONCLUSIONS: The results show a higher disease burden in patients with outpatient-treated or chronic HK in comparison to non-hyperkalemia patients, implying a higher proportion of disease-specific comorbidities, a higher number of hospitalizations as well as higher healthcare costs.