Age-Stratified Thirty-Day Rehospitalization and Mortality and Predictors of Rehospitalization among Patients with Systemic Lupus Erythematosus: a Medicare cohort study
Abstract
Objective Recent studies suggest young adults with lupus have high 30-day readmission rates, which may necessitate tailored readmission reduction strategies. To aid in riskstratification for future strategies, we measured 30-day rehospitalization and mortality among Medicare beneficiaries with lupus and determined rehospitalization predictors by age.
Methods In a 2014 20% national Medicare sample of hospitalizations, rehospitalization risk and mortality within 30 days of discharge were calculated for young (18-35), middle-aged (36-64), and older (65+) beneficiaries with and without lupus. Multivariable GEE models were used to predict rehospitalization among lupus patients by age group using patient, hospital, and geographic factors.
Results Among 1.39 million Medicare hospitalizations, 10,868 involved lupus beneficiaries. Hospitalized young adult lupus beneficiaries were more racially diverse, living in more disadvantaged areas, and had more comorbidities than older lupus and non-lupus beneficiaries. Thirty-day rehospitalization was 36% among young adult lupus beneficiaries – 40% higher than peers without lupus and 85% higher than older (65+) lupus beneficiaries. Longer length of stay and higher comorbidity risk score increased odds of rehospitalization in all age groups, while specific comorbid condition predictors and their impact varied. Our models, which incorporated neighborhood-level socioeconomic disadvantage, had moderate-to-good predictive value (c-statistics 0.67-0.77), outperforming administrative data models lacking comprehensive social determinants in other conditions.
Conclusion Young adults with lupus on Medicare had very high 30-day rehospitalization at 36%. Considering socioeconomic disadvantage and comorbidities provided good prediction of rehospitalization risk, particularly in young adults. Young lupus beneficiaries with comorbidities should be a focus of programs aimed at reducing rehospitalizations.