Initiation of β-blocker therapy and depression after acute myocardial infarction.

Introduction: Although β-blockers reduce mortality after acute myocardial infarction (AMI), early reports linking β-blocker use with subsequent depression have potentially limited their use in vulnerable patients. We sought to provide empirical evidence to support or refute this concern by examining the association between β-blocker initiation and change in depressive symptoms in AMI patients.

Methods: Using data from 2 US multicenter, prospective registries of AMI patients, we examined 1-, 6-, and 12-month changes in depressive symptoms after the index hospitalization among patients who were β-blocker-naïve on admission. Depressive symptoms were assessed using the validated 8-item Patient Health Questionnaire (PHQ-8), which rates depressive symptoms from 0 to 24, with higher scores indicating more depressive symptoms. A propensity-matched repeated-measures linear regression model was used to compare change in depressive symptoms among patients who were and were not initiated on a β-blocker after AMI.

Results: Of 3,470 AMI patients who were β-blocker-naïve on admission, 3,190 (91.9%) were initiated on a β-blocker and 280 (8.1%) were not. Baseline PHQ-8 scores were higher in patients not initiated on a β-blocker (mean 5.78 ± 5.45 vs 4.88 ± 5.11, P = .005). PHQ-8 scores were progressively lower at 1, 6, and 12 months in both the β-blocker (mean decrease at 12 months 1.16, P < .0001) and no-β-blocker groups (mean decrease 1.71, P < .0001). After propensity matching 201 untreated patients with 567 treated patients, initiation of β-blocker therapy was not associated with a difference in mean change in PHQ-8 scores at 1, 6, or 12 months after AMI (absolute mean difference with β-blocker initiation at 12 months of 0.08, 95% CI -0.81 to 0.96, P = .86).

Conclusions: Initiation of β-blocker therapy after AMI was not associated with an increase in depressive symptoms. Restricting β-blocker use because of concerns about depression appears unwarranted and may lead to undertreatment of AMI patients.