Value-based healthcare in ischemic stroke care: case-mix adjustment models for clinical and patient-reported outcomes

Background

Patient-Reported Outcome Measures (PROMs) have been proposed for benchmarking health care quality across hospitals, which requires extensive case-mix adjustment. The current study’s aim was to develop and compare case-mix models for mortality, a functional outcome, and a patient-reported outcome measure (PROM) in ischemic stroke care.

Methods

Data from ischemic stroke patients, admitted to four stroke centers in the Netherlands between 2014 and 2016 with available outcome information (N = 1022), was analyzed. Case-mix adjustment models were developed for mortality, modified Rankin Scale (mRS) scores and EQ-5D index scores with respectively binary logistic, proportional odds and linear regression models with stepwise backward selection. Predictive ability of these models was determined with R-squared (R²) and area-under-the-receiver-operating-characteristic-curve (AUC) statistics.

Results

Age, NIHSS score on admission, and heart failure were the only common predictors across all three case-mix adjustment models. Specific predictors for the EQ-5D index score were sex (β = 0.041), socio-economic status (β = − 0.019) and nationality (β = − 0.074). R²-values for the regression models for mortality (5 predictors), mRS score (9 predictors) and EQ-5D utility score (12 predictors), were respectively R² = 0.44, R² = 0.42 and R² = 0.37.

Conclusions

The set of case-mix adjustment variables for the EQ-5D at three months differed considerably from the set for clinical outcomes in stroke care. The case-mix adjustment variables that were specific to this PROM were sex, socio-economic status and nationality. These variables should be considered in future attempts to risk-adjust for PROMs during benchmarking of hospitals.

Predictors of physical independence at discharge after stroke rehabilitation in a Dutch population

The aim of this study was to identify predictors, available at admission, of physical independence at discharge from inpatient rehabilitation. Secondary aims were to identify predictors of functional gain and length of stay (LOS). We included 1310 adult stroke patients who were admitted for inpatient rehabilitation in five Dutch rehabilitation centres. Data on the Utrecht Scale for Evaluation of Clinical Rehabilitation at admission and discharge (physical and cognitive independence, mood, pain and fatigue), age, sex and in a subsample stroke characteristics as well were collected. A prediction model was created using random coefficient analysis. None of the stroke characteristics were independently associated with physical independence or functional gain at discharge, or LOS. Higher physical and cognitive independence scores and severe pain at admission were predictors of higher physical independence scores at discharge. Furthermore, lower physical independence scores, higher cognitive independence scores, less pain at admission and younger age predicted more functional gain. Finally, lower physical and cognitive independence scores at admission and younger age predicted longer LOS. Physical independence at admission was the most robust predictor for rehabilitation outcome in a Dutch rehabilitation setting. To a lesser extent, age, cognitive independence and pain predicted rehabilitation outcome after stroke. Treatment of cognition and pain should be taken into account during rehabilitation. Further work needs to be carried out to establish whether focusing on these factors improves outcome after rehabilitation.