Association between health system specialty pharmacy use and health care costs among national sample of Medicare Advantage beneficiaries

BACKGROUND: Health care expenditures are growing rapidly. There is a growing body of literature showing that health system specialty pharmacy is associated with improvement in clinical outcomes; however, there is a tack of data on its effect on health care costs and utilization. OBJECTIVE: To perform exploratory research assessing the association between health system specialty pharmacy use and health care costs and utilization. METHODS: A retrospective cohort study was conducted examining medical and pharmacy claims from 2018 and 2019 of Medicare Advantage beneficiaries. Opium Advisory Service's proprietary deidentified Normative Health Information database was used, which includes claims, membership, and provider data for 12.6 million Medicare Advantage members. Members who filled a prescription at a health system specialty pharmacy and had a specialty provider participating in the health system specialty pharmacy care model in clinic were assigned to the intervention group. Members who did not use a health system specialty pharmacy but had the same provider (provider benchmark group) or different provider (network benchmark group) were considered as comparisons. The network benchmark group was further refined to match variation in health care cost due to geography. The primary outcome measure was total health care costs (across the medical and pharmacy benefit) on a per-patient per-month basis. Secondary outcomes were selected utilization drivers and cost subcomponents. Cost and utilization metrics were calculated on a risk-adjusted basis using Centers for Medicare & Medicaid Services Hierarchical Condition Categories (CMS-HCC) risk score methodology. Differences were assessed for categorical variables with chi-square tests, and 2-tailed t-tests were used for continuous variables. RESULTS: Of the analytic sample of 9,780 members used in this study, 208 (2.1%) used health system specialty pharmacy services. During the 2018 baseline period, total health care costs and utilization were similar after CMS-HCC risk score adjustment ($9,520 among health system specialty pharmacy users; $8,691 among the provider benchmark group; $9,510 among the network benchmark group) but lower in 2019 ($7,060, $7,683, and $8,152, respectively). The differences in 2019 were primarily driven by savings in pharmacy and free-standing physician-related costs. CONCLUSIONS: Use of a health system specialty pharmacy is associated with a lower health care cost. Further study is required to analyze how drug and disease-specific interactions influence total health care costs and utilization for health system specialty pharmacy populations.