Background: Heart failure (HF) and chronic obstructive pulmonary disease (COPD) lead to unplanned
hospital activity, but our understanding of what drives this is incomplete.
Objectives: To model patient, primary care and hospital factors associated with readmission and mortality
for patients with HF and COPD, to assess the statistical performance of post-discharge emergency
department (ED) attendance compared with readmission metrics and to compare all the results for the
two conditions.
Design: Observational study.
Setting: English NHS.
Participants: All patients admitted to acute non-specialist hospitals as an emergency for HF or COPD.
Interventions: None.
Main outcome measures: One-year mortality and 30-day emergency readmission following the patient’s
first unplanned admission (‘index admission’) for HF or COPD.
Data sources: Patient-level data from Hospital Episodes Statistics were combined with publicly available
practice- and hospital-level data on performance, patient and staff experience and rehabilitation
programme website information.
Results: One-year mortality rates were 39.6% for HF and 24.1% for COPD and 30-day readmission rates were
19.8% for HF and 16.5% for COPD. Most patients were elderly with multiple comorbidities. Patient factors
predicting mortality included older age, male sex, white ethnicity, prior missed outpatient appointments, (long)
index length of hospital stay (LOS) and several comorbidities. Older age, missed appointments, (short) LOS and
comorbidities also predicted readmission. Of the practice and hospital factors we considered, only more
doctors per 10 beds [odds ratio (OR) 0.95 per doctor; p < 0.001] was significant for both cohorts for mortality,
with staff recommending to friends and family (OR 0.80 per unit increase; p < 0.001) and number of general practitioners (GPs) per 1000 patients (OR 0.89 per extra GP; p = 0.004) important for COPD. For readmission,
only hospital size [OR per 100 beds = 2.16, 95% confidence interval (CI) 1.34 to 3.48 for HF, and 2.27, 95% CI
1.40 to 3.66 for COPD] and doctors per 10 beds (OR 0.98; p < 0.001) were significantly associated. Some
factors, such as comorbidities, varied in importance depending on the readmission diagnosis. ED visits were
common after the index discharge, with 75% resulting in admission. Many predictors of admission at this visit
were as for readmission minus comorbidities and plus attendance outside the day shift and numbers of
admissions that hour. Hospital-level rates for ED attendance varied much more than those for readmission,
but the omega statistics favoured them as a performance indicator.
Limitations: Data lacked direct information on disease severity and ED attendance reasons; NHS surveys
were not specific to HF or COPD patients; and some data sets were aggregated.
Conclusions: Following an index admission for HF or COPD, older age, prior missed outpatient appointments,
LOS and many comorbidities predict both mortality and readmission. Of the aggregated practice and hospital
information, only doctors per bed and numbers of hospital beds were strongly associated with either outcome
(both negatively). The 30-day ED visits and diagnosis-specific readmission rates seem to be useful performance
indicators.
Future work: Hospital variations in ED visits could be investigated using existing data despite coding
limitations. Primary care management could be explored using individual-level linked databases.
Funding: The National Institute for Health Research Health Services and Delivery Research programme.