Association between the Emergency Heart Failure Mortality Risk Grade (EHMRG30-ST) and costs of care

Background — The Emergency Heart Failure Mortality Risk Grade (EHMRG30-ST) is a clinically validated model that predicts 30-day mortality in heart failure patients presenting to the emergency department (ED). However, the relationship between the EHMRG30-ST score and costs of care remains unclear. In this study, we explored the relationship between the EHMRG30-ST score and costs of care at 90 and 365 days after the index ED visit, and identified predictors of costs at 90 days.

Methods — We combined 2 chart review databases, including 11,407 patients presenting to the ED with heart failure between 2004-2007. We estimated the costs from administrative databases. We stratified patients into quintiles (Q) of EHMRG30-ST scores (Q1 = lowest risk; Q5 = highest risk), and compared the total costs in 2021 Canadian dollars at 90 and 365 days by score quintiles. We further examined the cost breakdown by categories. Finally, we used a generalized linear model to identify predictors of 90-day costs.

Results — Patients in the highest EHMRG30-ST risk group (Q5) had higher total costs compared to those for the lowest risk quintile (Q1) at 90 days (CAD$13,453 vs $24,484, P < 0.0001), and 365 days (CAD$29,401 vs $45,224, P < 0.0001). A positive correlation between EHMRG30-ST risk quintile and cost was observed for subcategories of hospital costs, long-term-care, and home care. Major predictors of 90-day costs were ejection fraction measurement and troponin levels.

Conclusions — Higher mortality risk as determined by the EHMRG30-ST score was associated with higher costs for up to 1 year after the initial ED presentation. Our study suggests that costs of care may be another potential dimension of the utility of prognostic risk scores.