Patients with bipolar disorder and those with asthma have significantly increased comorbidity rates, according to a meta-analysis published in Medicine, suggesting that clinicians should pay extra attention to the link, particularly in older patients.1
Out of 10 studies included in the investigation, Ming-Kung Wu, MD, and coauthors found in 4 studies that the prevalence rate of bipolar disorder was 2.12 times higher in those with asthma than in healthy controls, while an analysis of 6 studies showed a prevalence rate that was significantly higher (effect size, 1.86; 95% confidence interval: 1.40-247; P<.001) for asthma in patients with bipolar disorder than in healthy controls.
Asthma and bipolar disorder, while 2 distinct diseases, share a similar underlying inflammatory dysfunction, Ping-Tao Tseng, MD, a study author and attending staff of the Department of Psychiatry at Tsyr-Huey Mental Hospital, Koahsiung Jen-Ai’s Home in Taiwan, told Psychiatry Advisor. The study is one of the first to summarize current evidence about asthma and bipolar disorder occurring together, Dr Tseng said.
“This meta-analysis was based on observational studies. Therefore, we could only derive the conclusion of the observational results,” Dr Tseng concluded. “However, we suggest researchers investigate the possible common pathophysiology between these two diseases.”
Age Association in Asthma and Bipolar Disorder
In the meta-analysis of the prevalence rate of bipolar disorder in patients with and without asthma, the research included 4 studies of 50,358 patients with asthma and 109,218 healthy controls. Meta-regression was performed on data in women and no statistically significant association was found between the prevalence rate of bipolar disorder in patients with asthma and female sex, the authors wrote.
The researchers also analyzed the prevalence rate of asthma in patients with or without bipolar disorder in 6 studies of 5750 patients with bipolar disorder and 139,529 healthy controls. In the meta-regression, researchers found only a significantly positive association between the odds ratio of asthma in patients with bipolar disorder and mean age (slope: 0.015; P<.001).
“This meta-analysis provides the link between these 2 distinct diseases in clinical applications, which is especially important because in clinical practice, the physical problems are frequently missed in patients with severe mental illness,” the authors stated. “Thus, psychiatrists should be aware of possible comorbid asthma during the treatment of bipolar disorder. Medications with exacerbating effects on the asthmatic activity, such as beta blockers, must be avoided. At the same time, physicians should pay attention to distinguishing the symptoms of asthma and agitation during manic attack and avoid medications, such as steroids, that can induce manic symptoms.”
Wu, MK, Wang, HY, Chen, YW, et al. Significantly higher prevalence rate of asthma and bipolar disorder co-morbidity: A meta-analysis and review under PRISMA guidelines. Medicine. 2016;95(13):e3217.