Association of Patient Social, Cognitive, and Functional Risk Factors with Preventable Hospitalizations: Implications for Physician Value-Based Payment

Abstract
Background Ambulatory care-sensitive condition (ACSC) hospitalizations are used to evaluate physicians’ performance in Medicare value-based payment programs. However, these measures may disadvantage physicians caring for vulnerable populations because they omit social, cognitive, and functional factors that may be important determinants of hospitalization. Objective To determine whether social, cognitive, and functional risk factors are associated with ACSC hospitalization rates and whether adjusting for them changes outpatient safety-net providers’ performance. Design Using data from the Medicare Current Beneficiary Survey, we conducted patient-level multivariable regression to estimate the association (as incidence rate ratios (IRRs)) between patient-reported social, cognitive, and functional risk factors and ACSC hospitalizations. We compared outpatient safety-net and non-safety-net providers’ performance after adjusting for clinical comorbidities alone and after additional adjustment for social, cognitive, and functional factors captured in survey data. Setting Safety-net and non-safety-net clinics. Participants Community-dwelling Medicare beneficiaries contributing 38,616 person-years from 2006 to 2013. Measurements Acute and chronic ACSC hospitalizations. Results After adjusting for clinical comorbidities, Alzheimer’s/dementia (IRR 1.30, 95% CI 1.02–1.65), difficulty with 3–6 activities of daily living (ADLs) (IRR 1.43, 95% CI 1.05–1.94), difficulty with 1–2 instrumental ADLs (IADLs, IRR 1.54, 95% CI 1.26–1.90), and 3–6 IADLs (IRR 1.90, 95% CI 1.49–2.43) were associated with acute ACSC hospitalization. Low income (IRR 1.28, 95% CI 1.03–1.58), lack of educational attainment (IRR 1.33, 95% CI 1.04–1.69), being unmarried (IRR 1.18, 95% CI 1.01–1.36), difficulty with 1–2 IADLs (IRR 1.30, 95% CI 1.05–1.60), and 3–6 IADLs (IRR 1.44, 95% CI 1.16–1.80) were associated with chronic ACSC hospitalization. Adding these factors to standard Medicare risk adjustment eliminated outpatient safety-net providers’ performance gap (p < .05) on ACSC hospitalization rates relative to non-safety-net providers. Conclusions Social, cognitive, and functional risk factors are independently associated with ACSC hospitalizations. Failure to account for them may penalize outpatient safety-net providers for factors that are beyond their control.