Relation between process measures and diagnosis-specific readmission rates in patients with heart failure

To explore the relations between cause-specific readmission rates and National Heart Failure Audit process of care measures in patients admitted for heart failure (HF).

Using admissions data for all acute hospitals in England for April 2009-March 2012, we defined an index admission as the first emergency admission with a primary diagnosis of HF for at least three years. We compared risk-adjusted readmission rates for HF and for all non-HF diagnoses combined, risk-adjusted in-hospital mortality rates and performance on six Audit process measures.

14.7% of 123,644 patients died during the index admission. Of 105,441 index live discharges, 6853 (6.5%) were readmitted as emergencies within 7 days and 20,144 (19.1%) within 30 days. Index admission mortality rates correlated positively but weakly with non-HF readmission rates but not at all with HF rates. There was modest positive correlation at 7 days between HF and non-HF readmission rates (r=+0.24) but no significant relation at 30 or 365 days. All six process measures (prescribing of ACE inhibitors and beta-blockers, echocardiogram, cardiology inpatient and follow-up by cardiologist and HF liaison) correlated modestly but significantly with lower HF readmission rates at 7 days (r at most -0.26), only three did at 30 days and only cardiology follow-up did for non-HF at either 7 or 30 days; all associations were diminished at 365 days.

Hospitals scoring higher on evidence-based HF process measures had lower readmission rates, though the association seems limited to HF readmissions and is modest in strength and duration.