Long-Term Pattern and Associated Costs of Re-hospitalisations in Patients After Index Atrial Fibrillation Admission in Western Australia, 2011–2017

Aims
This study aimed to determine total and cardiovascular-specific re-hospitalisation patterns and associated costs within 2 years of index atrial fibrillation (AF) admission in Western Australia (WA).

Method
Patients aged 25–94 years, surviving an index (first-in-period) AF hospitalisation (principal diagnosis) from 2011 to 2015 were identified from WA-linked administrative data and followed for 2 years. Person-level hospitalisation costs ($ Australian dollar) were computed using the Australian Refined Diagnosis Related Groups and presented as median with first and third quartile costs.

Results
The cohort comprised 17,080 patients, 59.0% men, mean age 69.6±13.3 (standard deviation) years, and 59.0% had a CHA2DS2-VA (one point for congestive heart failure, hypertension, diabetes mellitus, vascular disease or age 65–74 years; two points for prior stroke/transient ischaemic attack or age ≥75 years) score of 2 or more. Within 2 years, 13,776 patients (80.6%) were readmitted with median of 2 (1–4) readmissions. Among total all-cause readmissions (n=54,240), 40.1% were emergent and 36.6% were cardiovascular-related, led by AF (19.5%), coronary events (5.8%), and heart failure (4.2%). The median index AF admission cost was $3,264 ($2,899–$7,649) while cardiovascular readmission costs were higher, particularly stroke ($10,732 [$4,179–23,390]), AF ablation ($7,884 [$5,283–$8,878]), and heart failure ($6,759 [$6,081–$13,146]). Average readmission costs over 2 years per person increased by $4,746 (95% confidence interval [CI] $4,459–$5,033) per unit increase in baseline CHA2DS2-VA score. The average 2-year hospitalisation costs per patient, including index admission, was $27,820 (95% CI $27,308–$28,333) and total WA costs were $475.2 million between 2011 and 2017.

Conclusions
Patients after index AF hospitalisation have a high risk of cardiovascular and other readmissions with considerable healthcare cost implications. Readmission costs increased progressively with baseline CHA2DS2-VA score. Better integrated management of AF and coexistent comorbidities is likely key to reducing readmissions and associated costs.