Major adverse cardiovascular events following acute coronary syndrome in patients with bipolar disorder

BACKGROUND: Persons with bipolar disorder (BD) have a higher cardiovascular mortality compared to the general population, partially explained by the increased burden of cardiovascular risk factors. Research regarding outcomes following acute coronary syndrome (ACS) in this population remains scarce.

DESIGN: This Danish register-based study included patients diagnosed with BD and ACS in the period between January 1st, 1995, to December 31st, 2013. Study participants were matched 1:2 to patients without BD on sex, date of birth, time of ACS diagnosis and comorbidities. The primary outcome of interest was major adverse cardiovascular events (MACE) a composite of all-cause mortality, reinfarction or stroke. MACE and its individual components were compared between patients with and without BD.

RESULTS: 796 patients with BD were compared to 1592 patients without BD, both groups had a mean age of first ACS of 66.5 years. MACE was 38% increased (HR 1.38 95% CI 1.25-1.54), all-cause mortality was 71% increased (HR 1.71 95% CI 1.52-1.92), stroke was 94% increased (HR 1.94 95% CI 1.56-2.41) and reinfarction rates were 17% lower (HR 0.83 95% CI 0.69-1.00) in the BD population compared to the population without BD. We also found higher prevalences of heart failure (9.1% vs. 6.5%), valve disease (5.3% vs. 3.5%), anemia (8.7% vs. 5.8%), chronic obstructive pulmonary disease (13.4% vs. 9.3%) and stroke (11.8% vs. 7.8%) in the population with BD at baseline, all p-values <0.05.

CONCLUSION: Bipolar disorder was associated with a higher risk of composite MACE, all-cause mortality, and stroke, after ACS compared to patients without BD.