Trends in ambulance transports and costs among Medicare beneficiaries, 2007-2018

Abstract

Background: The primary purpose of this study was to evaluate trends in ambulance utilization and costs among Medicare beneficiaries from 2007 to 2018. Community characteristics associated with ambulance use and costs are also explored.

Methods: Aggregated county-level fee-for-service (FFS) Medicare beneficiary claims data from 2007 to 2018 were used to assess ambulance transports per 1000 FFS Medicare beneficiaries and standardized inflation-adjusted ambulance costs. Multivariable linear mixed models were used to quantify trends in ambulance utilization and costs and to control for confounders.

Results: A total of 37,675 county-years were included from 2007 to 2018. Ambulance transports per 1000 beneficiaries increased 15% from 299 (95% CI: 291.63, 307.30) to 345 (95% CI: 336.91, 353.10) from 2007 to 2018. Inflation-adjusted standardized per user costs exhibited an increasing (1.04, 95% CI: 1.04, 1.05), but non-linear relationship (0.996, 95% CI: 0.996, 0.996) over time with costs peaking in 2012. Indicators of lower socioeconomic status (SES) were associated with increases in both ambulance events and costs (p < .0001). A higher prevalence of Medicare beneficiaries utilizing Skilled Nursing Facilities was associated with increased levels of ambulance events per 1000 beneficiaries (95% CI: 8.06, 10.63). Rural location was associated with a 38% increase in ambulance costs (95% CI 1.30-1.47) compared to urban location.

Conclusions: Numerous policy solutions have been proposed to address growing ambulance costs in the Medicare program. While ambulance transports and costs continue to increase, a bend in the ambulance cost curve is detected suggesting that one or more policies altered Medicare ambulance costs, although utilization has continued to grow linearly. Ambulance use and costs vary significantly with community-level factors. As policy makers consider how to address growing ambulance use and costs, targeting identified community-level factors associated with greater costs and utilization, and their root causes, may offer a targeted approach to addressing current trends.

Keywords: Ambulance; Emergency medical services; Health care costs; Health policy; Medicare.