The relationship among patient reported outcome measure scores with health care costs and inpatient admission: results from Utah mEVAL and value driven outcomes.

Background: Patient-reported outcomes measures (PROMs) profile patient health status, have been found to be helpful in identifying high health care utilizers, and may be useful in providing targeted interventions to decrease health care costs. In 2013 the University of Utah Health (UU Health) began collecting mental and physical health PROMs using Patient Reported Outcomes Measurement Information System (PROMIS) instruments through a tool called My Evaluation (mEVAL). In 2012 UU Health began cataloguing inpatient and outpatient healthcare-associated costs. The objective of this study was to identify association of poor PROMIS physical function and depression scores with (1) likelihood of inpatient hospitalization and (2) overall inpatient healthcare costs.

Methodology: This study was a retrospective observational cohort study including patients seen at UU Health between 1/2013 and 12/2017 who completed PROMIS instruments at an outpatient visit using the mEVAL platform. PROMIS instruments were completed prior to outpatient visits. The primary outcome was time to incident hospitalization modeled by using the Cox proportional hazards approach. For cost analysis, raw inpatient healthcare costs were fitted using a median regression model. Both results were adjusted.

Results: Of 92,383 people, the average age was 48 (SD 18.6); 57% were female; and 87% identified as non-Hispanic white. A total of 11,909 patients who completed one or both of the mEVAL PROMIS instruments were admitted. The average PROMIS physical function and depression scores were 44.9 and 51.1, respectively. Those with worse physical function scores and worse depression scores were more likely to be hospitalized [HR = 1.77, 95% confidence interval (CI) (1.678, 1.872); HR (95% CI) = 1.149 (1.059, 1.246), respectively]. A physical function score 1.5 SD below the mean was associated with an increased median hospitalization cost of $2496; there was no statistically significant association between depression score 1.5 SD above mean and hospitalization costs.

Conclusions: Poor physical function scores were associated with an increased risk of hospitalization and higher inpatient health costs, while poor depression scores were only associated with increased risk of hospitalization. Future work should examine if improvement in these PROMs alters these metrics.