CHADS-VASc predicts readmission, outcomes and resource utilization in patients undergoing coronary artery bypass grafting: A 7-year National Readmission Database study.

BACKGROUND

CHA2DS2-VASc score is used to assess thromboembolic risk in patients with atrial fibrillation (AF)/atrial flutter (AFL), however its utilization to predict outcomes and readmission at following discharge in patients undergoing coronary artery bypass grafting (CABG) regardless of AF/AFL presence is understudied. We sought to assess its utility in predicting outcomes, length of hospital stay (LOS), and healthcare-associated costs (HAC) in these patients.

METHOD

The National Readmission Database (NRD) was queried from 2010 to 2017 for patients with/without AF/AFL undergoing CABG using the International Classification of Diseases, Ninth and Tenth editions (ICD-9-&-10). Multiple regression analysis and multivariate analysis using Cox-Hazard analysis were used to evaluate outcomes up to 90-day readmission from discharge, LOS, and HAC against CHADS-VASc score (cut-off-score:6) were abstracted from the database.

RESULTS

Of the 420,458 patients that underwent CABG, 76,859 (18.3 %) were re-admitted to hospital within 90-days from discharge. Statistically significant increase in 90-day all-cause readmissions were demonstrated with increasing CHADS-VASc score [No AF/AFL vs AF/AFL: score-0 (2.4 % vs1.4 %), score-6 (3.1 % vs 4.5 %, p-value<0.0001]. Similar trends were seen in re-admissions for TIA/Stroke and heart failure. The survival rate for all events were lower with incremental increase in CHADS-VASc score (score-0 = 100 %; score-6 = 73 %, p-value<0.0001). Greater LOS and HAC was associated with increasing higher CHADS-VASc score (standardized-beta[β]; no AF/AFL vs AF/AFL: LOS = score-1: 0.08 vs 0.06, score-6: 0.12 vs 0.13. HAC = score-1: 0.02 vs 0.009, score-6: 0.02 vs 0.01, p-value <0.001).

CONCLUSION

CHADS-VASc score is an easy-to-use tool that predicts poorer outcomes, higher readmission, longer LOS, higher HAC, not just in patients with AF/AFL undergoing CABG, but also in those without AF/AFL.