Cardiovascular mortality in bipolar disorder: Population-based cohort study

Area of Science:

• Cardiovascular epidemiology
• Psychiatric comorbidities
• Public health

Background:

• Bipolar disorder (BD) is associated with a persistent and significant gap in cardiovascular disease (CVD) mortality compared to the general population.
• A limited evidence base on cause-specific CVD mortality in BD hinders the development of targeted preventive strategies.
• Addressing this knowledge gap is essential for reducing premature mortality in individuals with BD.

Purpose of the Study:

• To investigate the specific causes of excess cardiovascular disease (CVD) mortality in individuals diagnosed with bipolar disorder (BD).
• To identify leading causes of both absolute and relative excess CVD mortality within the BD population.
• To inform the development of targeted interventions for CVD prevention in BD.

Main Methods:

• Utilized Finnish nationwide data from 2004-2018 to identify individuals aged 15+ with a BD diagnosis.
• Calculated standardized mortality ratios (SMR) with 95% confidence intervals (CI) by comparing mortality rates in the BD cohort to the general population.
• Followed 53,273 individuals with BD for a total of 428,426 person-years.

Main Results:

• Cardiovascular disease (CVD) accounted for 26% of all deaths (5988 total deaths) in the BD cohort.
• Leading causes of relative excess CVD mortality included cardiomegaly (SMR 4.51), venous thromboembolism (SMR 3.03), cardiomyopathy (SMR 2.46), and hypertensive heart disease (SMR 2.12).
• Coronary artery disease (CAD) was the leading cause of absolute excess CVD mortality (SMR 1.47), with lower relative excess compared to structural/functional heart disorders.

Conclusions:

• Structural and functional heart disorders, particularly cardiomyopathy and hypertensive heart disease, significantly contribute to excess CVD mortality in bipolar disorder (BD), alongside coronary artery disease.
• These findings highlight the importance of addressing modifiable risk factors associated with these conditions.
• Prioritizing interventions targeting cardiomyopathy, hypertensive heart disease, and related factors is crucial for preventing premature CVD mortality in the BD population.