Respiratory disease in people with bipolar disorder: a systematic review and meta-analysis

People with bipolar disorder (BD) have an increased risk of premature mortality and the respiratory mortality rate is higher than those of the general population. To date, however, the evidence on respiratory disease in this population has not been meta-analyzed. We systematically review and meta-analyze the frequency of respiratory diseases in patients with BD and to compare prevalence and odds ratio (OR) with the general population. The systematic literature search was conducted in Pubmed, PsycINFO, Scielo and Scopus, with snowball search of reference and citation lists. Inclusion criteria were studies reporting diagnoses of respiratory diseases (asthma, chronic obstructive pulmonary disease (COPD), pneumonia, lung cancer and tuberculosis) in people with BD according to operationalized criteria and where possible, control group. Of the 2158 articles screened, 20 including 962,352 people with BD and 37,340,405 control group, met the inclusion criteria. In people with BD, the prevalence of COPD was 9.14% (95%CI: 6.61-12.5%), asthma 6.4% (95%CI: 4.56-8.91%), pneumonia 2.78% (95%CI: 2.51-3.08%) and lung cancer 0.44% (95%CI:0.23-0.84%). Compared to the general population, people with BD had significantly higher rates of COPD (OR: 1.73; 95% CI: 1.40-2.14), showing an increased rate in younger and female patients; asthma (OR: 1.91, 95% CI: 1.25-2.94), with a greater rate in younger patients; and pneumonia (OR: 2.82, 95% CI: 1.33-5.99). In the first meta-analysis on the topic, BD was associated with an increased risk of respiratory illness versus the general population. In COPD and asthma, young people and women are at particular risk. Prevention programs are urgently needed.