Was the decreasing trend in hospital mortality from heart failure attributable to improved hospital care? The Oregon experience, 1991-1995

Objective:To assess the trend in risk-adjusted hospital mortality from hear t failure. Study Design: Oregon hospital discharge data from 1991 through 1995 were an alyzed. Patients and Methods: A total of 29,530 hospitalizations because of heart f ailure in elderly patients (age greater than or equal to 65 years) were ide ntified from International Classification of Diseases, 9th Revision, codes 428.0-428.9. The logistic regression and life table analyses were used to a ssess the risk-adjusted trend in hospital mortality from heart failure. Results: From 1991 through 1995, 1757 (5.9%) patients with heart failure di ed in the hospital; 920 (52.4%) of them died within 3 days. The percentage of patients discharged to skilled nursing facilities increased from 6.1% in 1991 to 9.8% in 1995 (P value for trend < .001), whereas the percentage of patients discharged directly to home decreased from 69.2% in 1991 to 62.4% in 1995 (P value for trend < .001). The mean length of stay decreased from 5.15 days in 1991 to 3.97 days in 1995. The age- and sex-standardized mort ality rate decreased by 33.8% from 7.4 in 1991 to 4.8 in 1995 (P value for trend < .01). Additional adjustment for comorbidity using multiple logistic regression revealed a greater reduction of 41.0% in the mortality rate (od ds ratio = 0.59; 95% confidence interval = 0.50, 0.69) and a reduction of 4 6.0% in the 3-day mortality rate (odds ratio = 0.54; 95% confidence interva l = 0.43, 0.67) across the 5-year period. Life table analysis showed consis tently lower cumulative mortality rates during the first week after admissi on in 1995 compared with those in 1991 (P < .001). Conclusion: There was a decreasing trend over time in the risk-adjusted hos pital mortality rates from heart failure, which was not an artifact of decr easing length of stay. Our findings raised the possibility of improved hosp ital care for heart failure in Oregon.