Cost-effectiveness of an enhanced Paramedic Acute Stroke Treatment Assessment (PASTA) during emergency stroke care: Economic results from a pragmatic cluster randomized trial

Background: The Paramedic Acute Stroke Treatment Assessment (PASTA) trial evaluated an enhanced emergency care pathway which aimed to facilitate thrombolysis in hospital. A pre-planned health economic evaluation was included. The main results showed no statistical evidence of a difference in either thrombolysis volume (primary outcome) or 90-day dependency. However, counter-intuitive findings were observed with the intervention group showing fewer thrombolysis treatments but less dependency.
Aims: Cost-effectiveness of the PASTA intervention was examined relative to Standard Care (SC).
Methods: A within trial cost-utility analysis estimated mean costs and quality adjusted life years (QALYs) over 90 days’ time horizon. Cost were derived from resource utilisation data for individual trial participants. QALYs were calculated by mapping modified Rankin scale scores to EQ-5D-3L utility tariffs. A post-hoc subgroup analysis examined cost-effectiveness when trial hospitals were divided into compliant and non-compliant with recommendations for a stroke specialist thrombolysis rota.
Results: The trial enrolled 1214 patients: 500 PASTA and 714 SC. There was no evidence of a QALY difference between groups [0·007 (95%CI -0·003 to 0·018)] but costs were lower in the PASTA group [-£1473 (95%CI: - £2736 to -£219)]. There was over 97.5% chance that the PASTA pathway would be considered cost-effective. There was no evidence of a difference in costs at seven thrombolysis rota compliant hospitals but costs at eight non-complaint hospitals costs were lower in PASTA with more dominant cost-effectiveness.
Conclusions: Analyses indicate that the PASTA pathway may be considered cost-effective, particularly if deployed in areas where stroke specialist availability is limited.
Trial Registration: ISRCTN12418919 www.isrctn.com/ISRCTN12418919