The Increased Clinical and Economic Burden of Hyperkalemia in Medicare Patients Admitted to Long-Term Care Settings.

Abstract

Older patients are at increased risk for hyperkalemia (HK). This study describes the prevalence, recurrence, and clinical and economic burden of HK in Medicare patients admitted to a long-term care (LTC) setting. Retrospective cohort study using 100% Medicare Fee-for-Service (FFS) claims identified patients aged≥65years with index admission between 2017 and 2019 to a LTC setting (skilled nursing, home health, inpatient rehabilitation, or long-term acute care). Beneficiaries were required to have 12months continuous medical and pharmacy coverage prior to index LTC admission and≥30days after LTC discharge (follow-up). Patient characteristics, healthcare resource utilization, and costs were assessed. HK was defined as ICD-10 diagnosis code E87.5 in any claim position or Medicare Part D fill for oral potassium binder. Of 4,562,231 patients with a LTC stay, the prevalence of HK was 14.7% over the full study period (pre-index, index stay, and follow-up). Excluding those with HK only during the follow-up period resulted in 4,081,103 patients. Of these, 290,567 (7.1%) had HK and 3,790,536 (92.9%) did not have HK during or within 14days prior to index LTC stay. The HK recurrence rate during index stay and follow-up was 48.3%. Unmatched HK versus non-HK patients were more often male (43.0% vs. 35.4%), Black (13.5% vs. 8.0%), dual eligible for Medicaid (34.2% vs. 25.0%), with higher mean Charlson Comorbidity Index scores (6.2 vs. 3.9) (all p<0.0001). After propensity matching, HK patients were 2.2times more likely to be hospitalized, with higher mortality (30.8% vs. 21.5%) and higher total healthcare costs during both index stay (US$26,520 vs. $18,021; p<0.0011) and follow-up ($57,948 vs. $41,744 (p<0.0011) versus matched non-HK patients. Prevalence and recurrence of HK was high among LTC patients, and HK was associated with significantly greater clinical and economic burden during and post-LTC.