The effects of perioperative β-blockers on mortality in patients undergoing non-cardiac surgery in real world: A meta-analysis of cohort studies

The Effect of Intravenous and Oral Beta-Blocker Use in Patients with Type B Thoracic Aortic Dissection

BACKGROUND

Beta-blockers have become the cornerstone for medical management in patients with chronic type B aortic dissection (TBAD). However, the effect of being on and/or receiving intravenous beta-blockers during hospitalization on outcomes of surgical repair of TBAD is not fully described. We sought to investigate this association during open surgical repair (OSR) and endovascular (Endo) intervention for nontraumatic TBAD.

METHODS

The Premier Healthcare Database was inquired (June/2009-March/2015). Patients with nontraumatic isolated TBAD were identified via ICD-9-CM diagnosis and procedural codes. Patients with codes that indicated TAAD were excluded. In-hospital mortality, cardiac complications (CHF, MI, arrythmia) and stroke were evaluated. Log binomial regression analyses with bootstrapping were performed to assess the relative risk of adverse outcomes.

RESULTS

A total of 1,752 were admitted for OSR (54.3%) and Endo (45.7%) TBAD repair. Use of oral beta blocker (BB) was 16.0% in OSR and 56.4% in Endo groups. In each arm, patients on BB were more likely to be diabetic, on aspirin or statin and more likely to receive additional IV BB than nonBB patients. There was no significant difference in age, sex, race, or prior history of CHF between BB and nonBB groups. Mortality was proportionally lower in patients on BB in OSR group (7.9% vs. 16.7%; P = 0.006) and Endo (3.3% vs. 9.2%; P < 0.001). The adjusted relative risk for mortality and stroke were significantly lower in oral BB recipients compared with none [aRR (95% CI): 0.53 (0.32-0.90) and 0.46 (0.25-0.87); both P ≤ 0.02]. IV metoprolol was the only IV BB that reduced mortality [aRR (95% CI): 0.62 (0.46-0.85); P = 0.003]. A dose of ≤10 mg was associated with significant mortality reduction: 6.3% (3.0-9.5%) compared with 8.1% (4.6-11.6%) in no IV BB group. Cardiac complications were not affected by BB use.

CONCLUSIONS

For patients with nontraumatic TBAD, use of oral BB was associated with significant protection against in-hospital mortality and stroke following repair. Metoprolol was the only Intravenous BB type associated with improved survival. Further research is warranted to elucidate the effect of beta-blockers on the long-term surgical outcomes of TBAD.

Patterns of β-blocker initiation in patients undergoing intermediate to high-risk noncardiac surgery

BACKGROUND

Based on 2 small randomized controlled trials (RCTs) from the 1990s, β-blockers were promoted to prevent perioperative cardiac events in patients undergoing noncardiac surgery. In 2008, a large RCT (POISE trial) showed an increased mortality risk associated with perioperative β-blockade, raising concerns about an extensive β-Blocker use.

OBJECTIVES

The objective of the study is to examine patterns of β-Blocker initiation among patients undergoing noncardiac elective surgery in the US.

METHODS

From a large, nationwide US health care insurer, we identified patients ≥18 years old who underwent moderate- to high-risk noncardiac elective surgery between 2003 and 2012 and initiated a β-Blocker within 30 days before surgery. We evaluated temporal trends and assessed the impact of the POISE trial on perioperative β-Blocker initiation. We also evaluated patient characteristics and examined the effect of temporal proximity to surgery on the likelihood of β-Blocker initiation.

RESULTS

Of 499,752 patients undergoing surgery, 9,014 (18 per 1,000 patients) initiated a β-Blocker. β-Blocker initiation increased from 12 per 1,000 patients in 2003 to 23 before POISE, after which it decreased to 14 by December 2012 (P = .0001). β-Blocker initiation remained relatively high among patients undergoing vascular surgery or with Revised Cardiac Risk Index score ≥ 2. Proximity to surgery was highly predictive of β-Blocker initiation (odds ratio 3.34, 95% CI 3.17-3.51).

CONCLUSIONS

After a period of a rapidly increasing trend, perioperative β-Blocker initiation decreased sharply in the second half of 2008 and continued to decrease afterwards. β-Blocker initiation remained relatively high in patients with Revised Cardiac Risk Index score ≥2 and in those undergoing major vascular surgery.