Abstract A150: Prehospital Blood Pressure Lowering in Likely Intracerebral Hemorrhage Patients Is a Cost-Effective Treatment Strategy in Both US and China

Introduction: Prehospital blood pressure lowering in hyperacute stroke patients improves outcome in intracerebral hemorrhage (ICH) but worsens outcome in ischemic stroke (IS) patients, per the INTERACT 4 trial. Modeling has shown existing prehospital ICH recognition scales (e.g. CASPR) and point-of-care tests (e.g serum GFAP) have sufficient sensitivity/specificity in selecting a population strongly enriched for ICH to make field antihypertensive therapy in test-positive patients clinically beneficial. The objective of this study was to investigate if this treatment strategy would also be cost-effective. Methods: Modeling inputs were: 1) age- and sex-specific life expectancies from US and China actuarial tables; 2) mRS disability weights and disability-level specific mortality hazard ratios for ICH and IS; 3) 3m mRS outcomes for ICH and IS patients from INTERACT 4; and 4) costs of prehospital BP medication in the US (nifedipine) and China (urapidil). Aggregating these data, we calculated incremental cost-effectiveness ratios (ICERs) for prehospital BP-lowering therapy over a range of positive predictive values (PPVs) for ICH of prehospital assessment tests from 50%-100%. Results: Table 1 shows ICER results for PPVs between 50%-100% for male and female US and Chinese patients. Treating patients test-positive for likely ICH was highly cost-effective in all scenarios. For example, at 80% PPV, prehospital BP-lowering cost $28 (dollars) per quality-adjusted life year gained in US male patients and ¥ 109 RMB (renminbi) per QALY in Chinese female patients. Fig 1.1 depicts model results in US male and female patients. In the prototypical male US patient age, DALYs with BP-lowering were 11.4 (YLL 9.6+YLD 1.8) vs without BP-lowering 11.7 (YLL 10.0+YLD 1.8). The average quality-adjusted life year gained for each treated male patient was 0.3y. Figure 1.2 depicts results in Chinese patients. In the prototypical Chinese female patient, DALYs with BP-lowering were 20.0 (YLL 16.9+YLD 3.1) vs without BP-lowering 20.7 (YLL 17.6+YLD 3.1). The average quality-adjusted life year gained for each treated female patient was 0.6y. Conclusion: Prehospital BP-lowering treatment in hyperacute stroke patients assessed as likely having ICH would be highly cost-effective at positive predictive values attainable by currently available ICH diagnostic scales and point-of-care tests. These findings support pivotal trial testing of this promising treatment approach.