30-Day Heart Failure Readmission and Post-Discharge Healthcare Use Among Older Australians: A Linked-Data Mixed-Methods Study

Abstract Background: Heart failure (HF) is a major public health challenge in ageing populations and a leading cause of unplanned hospital readmissions. Biological, social, and economic factors contribute to recurrent hospitalisation, but gaps remain in understanding how these factors interact and patterns of healthcare use following hospitalisation. Methods: We conducted an explanatory sequential mixed-methods study of patients aged ?60 years with an HF hospital admission between 2016 and 2020 who completed the Sax Institute?s 45 and Up Study baseline questionnaire. Data were linked to Admitted Patient Data Collection, Medicare Benefits Schedule, and Pharmaceutical Benefits Scheme data. HF readmission within 30 days of the index admission was the outcome. Cox proportional hazards models estimated crude and adjusted hazard ratios (HRs and adjHRs) with 95% confidence intervals (CIs). Kaplan-Meier curves and log-rank tests compared survival between groups. Time-series plots mapped healthcare interactions over 1 year following the index admission. Results: Among 4,252 patients with HF, 409 were readmitted within 30 days. Significant predictors included age ?80 years (adjHR, 1.30; 95%CI, 1.01?1.67), 1 chronic condition (adjHR, 2.49; 95%CI, 1.41?4.40), ?2 chronic conditions (adjHR, 1.75; 95%CI, 1.04?2.95), and alcohol consumption above national guidelines (adjHR, 1.45; 95%CI, 1.06?1.98). Time-series analysis indicated that participants with readmission had more frequent out-of-hospital health service contact following their initial HF admission than those without readmission. Conclusions: Older age, chronic conditions, and high alcohol intake increased 30-day HF readmission risk. Differences in healthcare use after admission highlight opportunities for targeted and coordinated post-discharge care.