The Impact of Disability and Social Determinants of Health on Condition Specific Readmissions beyond Medicare Risk Adjustments: A Cohort Study
BackgroundReadmission rates after pneumonia, heart failure, and acute myocardial infarction hospitalizations are risk adjusted for age, gender, and medical comorbidities and used to penalize hospitals.ObjectiveTo assess the impact of disability and social determinants of health on condition specific readmissions beyond current risk adjustment.Design, Setting, and ParticipantsRetrospective cohort study of Medicare patients using 1) linked Health and Retirement Study Medicare claims data (HRS CMS) and 2) Healthcare Cost and Utilization Project State Inpatient Databases (Florida, Washington) linked with ZIP Code level measures from the Census American Community Survey (ACS HCUP) Multilevel logistic regression models assessed the impact of disability and selected social determinants of health on readmission beyond current risk adjustment.Main MeasuresOutcomes measured were readmissions =30 days after hospitalizations for pneumonia, heart failure, or acute myocardial infarction. HRS CMS models included disability measures (activities of daily living [ADL] limitations, cognitive impairment, nursing home residence, home healthcare use) and social determinants of health (spouse, children, wealth, Medicaid, race) ACS HCUP model measures were ZIP Code percentage of residents =65 years of age with ADL difficulty, spouse, income, Medicaid, and patient level and hospital level race.Key ResultsFor pneumonia, =3 ADL difficulties (OR 1.61, CI 1.079 2.391) and prior home healthcare needs (OR 1.68, CI 1.204 2.355) increased readmission in HRS CMS models (N 1631) ADL difficulties (OR 1.20, CI 1.063 1.352) and 'other' race (OR 1.14, CI 1.001 1.301) increased readmission in ACS HCUP models (N 27,297) For heart failure, children (OR 0.66, CI 0.437 0.984) and wealth (OR 0.53, CI 0.349 0.787) lowered readmission in HRS CMS models (N 2068) while black (OR 1.17, CI 1.056 1.292) and 'other' race (OR 1.14, CI 1.036 1.260) increased readmission in ACS HCUP models (N 37,612) For acute myocardial infarction, nursing home status (OR 4.04, CI 1.212 13.440) increased readmission in HRS CMS models (N 833) 'other' patient level race (OR 1.18, CI 1.012 1.385) and hospital level race (OR 1.06, CI 1.001 1.125) increased readmission in ACS HCUP models (N 17,496).ConclusionsDisability and social determinants of health influence readmission risk when added to the current Medicare risk adjustment models, but the effect varies by condition.
Journal of General Internal Medicine