SENIOR HIGH COST HEALTHCARE USERS: HOW DO THEY DIFFER?

High cost users (HCUs) are a small proportion of the population that use disproportionate healthcare resources. In 2011, 5% of the population in Ontario, Canada accounted for 65% ($19.8 billion) of provincial health expenditures. Understanding HCU multi-morbidity and drug use is required to target interventions to improve clinical outcomes and contain healthcare costs. This study aimed to compare senior HCUs to non-HCUs based on demographics, co-morbidities, medication use, health service utilization, clinical outcomes and costs. We conducted a retrospective population-based matched cohort analysis of incident senior HCUs defined as Ontarians age ≥ 66 years in the top 5% of total healthcare costs in FY2013. Healthcare and prescription drug utilization data were obtained from health administrative databases. The primary outcomes were annual total healthcare expenditures per patient, total drug costs per patient and drug-to-total healthcare expenditure ratio. Secondary outcomes were one-year mortality and hospitalization rate. Senior HCUs (n=176,604) accounted for $4.9 billion in total healthcare expenditures and $433 million in medication costs in FY2013. Compared to non-HCUs (n=529,812) on a per patient basis, HCUs incurred higher total healthcare costs ($27,697 vs. $2233) and higher medication costs ($2453 vs. $842). HCUs were characterized by greater polypharmacy (>5 medications, 87.7% vs. 47.6%) and multi-morbidity (median John Hopkins Expanded Diagnosis Clusters [EDCs], 14 vs. 10). HCUs had higher annual mortality (10.39% vs. 0.72%) and hospitalization rates (3.20 vs. 0.06 hospitalizations per 1000 person-years). Compared to non-HCUs, senior HCUs are frail, multi-morbid and vulnerable. The contribution of prescribing and medication utilization quality deserves further study.