30-day potentially preventable hospital readmissions in older patients: Clinical phenotype and health care related risk factors

Purpose: Early readmission rate has been regarded as an indicator of in-hospital and postdischarge quality of care. Evaluating the contributing factors is crucial to optimize the healthcare and target the intervention. In this study we evaluated the potential for preventing 30-day hospital readmission in a cohort of older patients and identified possible risk factors for readmission. Patients and methods: Diagnosis-Related Group (DRG) codes of patients consecutively hospitalized for acute disease in the Geriatrics Unit of the University Hospital of Pisa within a 1-year window were recorded. All the patients had received a comprehensive geriatric assessment. Crossing and elaboration of the DRG codes was performed by the Potentially Preventable Readmission Grouping software (3M™ Corporation). DRG codes were classified as stand-alone admissions (SA), index admissions (IA) and potentially preventable readmissions (PPR) within a time window of 30 days after discharge. Results: In total, 1263 SA and 171 IA were identified, with an overall PPR rate of 11.9%. Hospitalizations were significantly longer in IA and PPR than SA (p<0.05). The more frequent readmission causes were acute heart failure, pulmonary edema, sepsis, pneumonia and stroke. In acute heart failure a nonlinear U-shaped readmission trend (with nadir at 5 days of hospitalization) was observed while, in all the other DRG codes, the PPR rate increased with increasing length of hospitalization. Comprehensive geriatric assessment showed a significantly lower degree of disability and comorbidity in SA than IA patients. At stepwise regression analysis, a high degree of disability and comorbidity as well as the diagnosis of sepsis emerged as independent risk factors for PPR. Conclusion: Addressing PPR is crucial, especially in older patients. The adequacy of treatment during hospitalization (especially in cases of sepsis) as well as the setting of a comprehensive discharge plan, accounting for comorbidity and disability of the patients, are essential to reduce PPR.