Substantial between-hospital variation in outcome following first emergency admission for heart failure.
BACKGROUND: Following hospitalization with a range of cardiovascular disorders, substantial variation has been noted in clinical outcome, both between and within countries. OBJECTIVES: To examine the variation, between hospitals, in the clinical outcomes of death and readmission following hospitalization with heart failure in Scotland. Setting All 29 acute hospitals in Scotland with more than 200 beds. PATIENTS: All 31 452 patients discharged from these hospitals between January 1990 and December 1995 with a first-ever, primary, diagnosis at discharge/death of heart failure. ANALYSIS: An analysis of the Scottish database of discharge summaries linking index admissions with subsequent admissions and deaths. Death rates and readmission rates were adjusted for baseline age, co-morbidity and socio-economic status and were calculated at different time periods (inpatient, 30 days, 1 year). Rates were calculated separately for large teaching hospitals (n=6, category A), large general hospitals with specialist units (n=8, category B) and medium sized general hospitals with limited specialist units (n=15 category C). RESULTS: A total of 31 452 patients were discharged between 1990-1995 - 10 219 (33%), 9735 (31%) and 11 498 (37%) to category A, B and C hospitals, respectively. The national, average, inpatient case fatality rate was 15.3%, ranging, in individual hospitals, from the lowest rate of 8.5% to the highest rate of 23.4%. The average 1 year case fatality rate was 42.4%, ranging between 35.3% and 50.8%. A similar two- to threefold variation was found in hospital readmission rates - thus the average 30 day readmission rate was 5.3% (lowest 3.3%, highest 7.3%). This variation, in both case-fatality and readmission rates, was apparent within all three groups of hospitals and persisted after adjustment for the baseline factors outlined above. CONCLUSIONS: A patient admitted to one Scottish hospital with heart failure may be two to three times more likely to die or be readmitted, both in the short and longer term, compared to a patient admitted to another hospital. Although we may not have accounted for some sources of variation, it is both surprising and disturbing that large, statistically significant, differences in adjusted death and readmission rates can apparently exist for such an important condition in a relatively small country with generally homogenous health care provision. Further, detailed investigation of this apparent variation is required.