Beta Blockers as Primary and Secondary Prevention for Aortic Dissections in Nonsyndromic Patients With Hypertension

BACKGROUND: Recommendations for beta blockers in preventing aortic dissection (AD) and improving postdissection survival in nonsyndromic patients with hypertension are based on limited evidence. METHODS: This nationwide, population-based study combined a nested case-control and historical cohort design. Using Danish health care registries, all hospitalized adult patients with AD from 1996 to 2016 were identified and validated. Patients with bicuspid aortic valves or connective tissue disorders were excluded. In the case-control analysis, 1657 validated AD cases were matched 1:10 (±1) with 16 139 controls with hypertension based on age, sex, index date, and cumulative antihypertensive drug use. Long-term beta blocker use was defined as ≥2000 defined daily doses (DDD). In the cohort analysis, 2120 validated survivors of AD were followed for 5 years to assess postdissection mortality stratified by beta blocker use. RESULTS: Long-term beta blocker use was associated with increased odds of AD type A (adjusted odds ratio [aOR], 1.7 [95% CI, 1.3-2.3]) and AD type B (aOR, 3.7 [95% CI, 2.7-5.2]) compared with never-users. A dose-dependent risk increase was observed for AD type B (aOR, 1.4 [95% CI, 0.8-2.2] for DDD 100-199; aOR, 3.9 [95% CI, 1.6-9.8] for DDD ≥10 000). Beta blocker use was associated with higher 5-year all-cause mortality in survivors of AD type A (adjusted hazard ratio [aHR], 1.5 [95% CI, 0.99-2.23]) and AD type B (aHR, 1.5 [95 %CI, 1.0-2.3]) compared with never-users. CONCLUSIONS: Beta blocker use did not reduce AD risk or improve outcomes in survivors of AD compared with other antihypertensive agents. Although clinically relevant data as aortic diameters and blood pressure were not available, these findings challenge current clinical practice and highlight the need for randomized trials.