Changes in Heart Failure Outcomes After a Province-Wide Change in Health Service Provision A Natural Experiment in Alberta, Canada

Abstract

Background— The Alberta Cardiac Access (ACA) initiative was implemented in the spring of 2008 to increase access to specialized heart failure (HF) clinics after hospital discharge. Methods and Results— We identified all adults hospitalized with a most responsible diagnosis of HF between April 1999 and December 2009. We randomly selected 1 episode of care per patient and evaluated outcomes using interrupted time series: the a priori specified primary outcome was all-cause readmission or death in the first 30 days postdischarge. Between 1999 and 2009, median length of stay increased from 8 days to 10 days ( P <0.001), and 30-day mortality increased from 9.1% to 11.5% ( P <0.001) in the 37891 HF hospitalizations we examined. However, these temporal changes were attributable to the increasing comorbidity burden over time: the adjusted Risk Ratio for 30-day mortality in 2009 versus 1999 was 0.99, 95% confidence interval, 0.86 to 1.15. After adjusting for secular trends, the ACA initiative was associated with changes in 30-day postdischarge mortality or readmission rates (which were increasing 0.3% per month [0.2%–0.3%] pre-ACA and decreased 1.4% per month [0.3%–2.5%] in the 18 months post-ACA; P =0.008). After roll out of the ACA initiative, patients discharged from vanguard regions (those that had specialized HF clinics) exhibited lower 30-day postdischarge death/readmission rates than those discharged from other areas of the province (18.6% versus 22.2%, adjusted odds ratio 0.83, 95% confidence interval, 0.75–0.93). Conclusions— An initiative which increased specialized HF clinic access was associated with a statistically significant improvement in 30-day postdischarge mortality/readmission rates.