A large population-based study has found that people with bipolar II disorder face a significantly elevated risk of early death compared to individuals of the same age and sex without the condition. The research, published in JAMA Network Open, analysed data from Taiwan’s national health and death registries, covering more than 11,000 individuals diagnosed with bipolar II disorder and 45,708 matched controls, with a mean follow-up period of approximately 7.3 years.
Bipolar II disorder is characterised by recurrent depressive episodes and hypomanic episodes of elevated mood and energy. Unlike bipolar I disorder, manic episodes in bipolar II are generally less severe and less likely to require hospitalisation. However, the condition has historically been grouped with bipolar I in research, limiting understanding of its specific mortality risks.
Statistical modelling revealed that participants with bipolar II disorder were approximately 60% more likely to die from any cause during the study period. The risk of death from physical illness, including cardiovascular, respiratory, and digestive diseases, was 37% higher than in the general population. The risk of death from unnatural causes, including accidents, suicide, and violence, was nearly 4.5 times greater.
The study also found that individuals with bipolar II disorder had a 24% higher overall mortality risk compared to those with bipolar I disorder, though the elevated risk from unnatural causes was broadly similar between the two groups. Approximately 62% of bipolar II participants were women, and the cohort included individuals aged 12 and older.
The authors acknowledge that findings are drawn from a single national dataset and do not capture episode severity, frequency, or lifestyle variables, which may influence mortality. They call for further research to support integrated psychiatric and medical care for this population.
Source: Hsu C-W et al. All-Cause and Cause-Specific Mortality in Patients With Bipolar II Disorder. JAMA Network Open (2026). DOI: 10.1001/jamanetworkopen.2026.5535
Bipolar II disorder is characterised by recurrent depressive episodes and hypomanic episodes of elevated mood and energy. Unlike bipolar I disorder, manic episodes in bipolar II are generally less severe and less likely to require hospitalisation. However, the condition has historically been grouped with bipolar I in research, limiting understanding of its specific mortality risks.
Statistical modelling revealed that participants with bipolar II disorder were approximately 60% more likely to die from any cause during the study period. The risk of death from physical illness, including cardiovascular, respiratory, and digestive diseases, was 37% higher than in the general population. The risk of death from unnatural causes, including accidents, suicide, and violence, was nearly 4.5 times greater.
The study also found that individuals with bipolar II disorder had a 24% higher overall mortality risk compared to those with bipolar I disorder, though the elevated risk from unnatural causes was broadly similar between the two groups. Approximately 62% of bipolar II participants were women, and the cohort included individuals aged 12 and older.
The authors acknowledge that findings are drawn from a single national dataset and do not capture episode severity, frequency, or lifestyle variables, which may influence mortality. They call for further research to support integrated psychiatric and medical care for this population.
Source: Hsu C-W et al. All-Cause and Cause-Specific Mortality in Patients With Bipolar II Disorder. JAMA Network Open (2026). DOI: 10.1001/jamanetworkopen.2026.5535
