Abstract 13033: Clinical Evidence, Practice Guidelines, and Perioperative Beta-Blocker Utilization
Introduction: Views regarding beta-blockade for noncardiac surgery have changed considerably. After being received enthusiastically following small positive randomized trials (e.g. DECREASE-I), doubts emerged after larger observational and randomized (e.g. DIPOM, POISE) studies. The changing evidence also led to altered guideline recommendations. We conducted a time-series analysis to evaluate the impact of changing evidence and guidelines on prescriptions for perioperative beta-blockers.
Methods: Following REB approval, we conducted a population-based time-series analysis of patients (≥66 years) who had major elective noncardiac surgery in Ontario, Canada (1 April 1999 to 31 March 2010). New beta-blocker use was defined as ≥1 prescriptions within 60 days before surgery, and no other prescriptions in the year before surgery. For comparison, we evaluated trends in new statin use. Time-series analysis (ARIMA models) was used to evaluate the impact of clinical evidence and practice guidelines on prescription rates.
Results: The analysis included 249,828 procedures. The overall new beta-blocker prescription rate was 40.3 per 1000 procedures. It rose from 26.3 per 1000 procedures in April 1999, and peaked during the 1st quarter of 2005 (62.7 per 1000 procedures), after which it fell to 19.7 per 1000 procedures by March 2010. Rates of new statin prescriptions instead rose through the study. The directional change in beta-blocker trends coincided (P=0.004) with publication of a cohort study by Lindenauer et al. (July 2005). Prescription trends were not altered (P=0.76) after the POISE trial was published (May 2008). There was no shift in trends after publication of ACC/AHA guidelines in 2002 (P=0.13) and 2006 (P=0.76).
Conclusions: Rates of new preoperative beta-blocker use in Ontario underwent marked changes between 1999 and 2010. The changes were influenced by a large cohort study by Lindenauer et al., but not by the POISE trial or revised practice guidelines.
- © 2011 by American Heart Association, Inc.