"Our study differs from previous literature in that it uses a nationally representative sample and incorporates potential covariates, thus making our findings more generalizable and reliable."
The risk of cough and asthma in persons with severe depression was 3.32 times and 2.84 times higher, respectively, than that in those without depression, reported researchers.
New data show that depression severity is associated with respiratory symptoms (ie, cough, wheezing), asthma, and chronic obstructive pulmonary disease (COPD).
The risk of cough and asthma in persons with severe depression was 3.32 times and 2.84 times higher, respectively, than that in persons without depression, and the risk of asthma and COPD was 2.4 times and 2.6 times higher, respectively, according to findings published in Respiratory Medicine.
“COPD patients have a high prevalence of anxiety and depression, and depression appears to be an independent factor in acute exacerbations of COPD,” wrote first author Yuefeng Sun, of Shandong University of Traditional Chinese Medicine in China, and colleagues. “The prevalence of depression and anxiety disorders in [people with asthma] is at least twice as high as in the general population, and depression contributes to the worsening of asthma.”
Researchers used data from the National Health and Nutrition Examination Survey (NHANES), from 2005 to 2012, to further explore the relationship between depression severity and respiratory symptoms (cough, wheeze, exertional dyspnea), and between depression and asthma and COPD through weighted logistic regression analysis.
"Our study differs from previous literature in that it uses a nationally representative sample and incorporates potential covariates, thus making our findings more generalizable and reliable."
A total of 10 412 participants (mean age, 59.7 years; 53.2% women) from NHANES were included in the study and weighted to reflect the US population, according to the study.
Investigators screened for depressive symptoms using scores from the Patient Health Questionnaire 9 program, with a higher score (20-27) indicating severe depression and a lower score (0-4) signaling no depression.
When Sun and colleagues adjusted for age, sex, race/ethnicity, marital status, household ratio of income to poverty, educational achievement, smoking status, body mass index, cardiovascular disease, diabetes mellitus, and hypertension, they found that patients with severe depression had a 3.32-times (odds ratio [OR] 3.32, 95% CI 1.57–7.05) higher likelihood of developing cough and 2.84-times (OR 2.84, 95% CI 1.52–5.31) higher likelihood of developing wheezing than those without depression.
“In addition, higher depression severity was associated with a higher risk of asthma and COPD,” wrote investigators.
Compared to participants without depression, the risk of developing asthma was 2.4-times (OR 2.41, 95% CI 1.37–4.24) higher for those with major depression; the risk was 2.6-times (OR 2.57, 95% CI 1.24–4.92) higher for developing COPD for those with moderate depression, according to the study results.
“Of note, our findings showed an interaction between the prevalence of respiratory symptoms and depression across gender,” added Sun and coauthors.
Among men, results showed that depression was associated with higher cough (OR 3.21, 95% CI 2.13–4.84; P < .001), wheezing (OR 2.66, 95% CI 1.97–3.59, P < .001), and exertional dyspnea (OR 2.78, 95% CI 2.00–3.85, P < .001) compared to no depression.
In terms of race/ethnicity, investigators observed higher odds for cough with depression among Mexican Americans (OR 2.76, 95% CI 1.49-5.13; P = .02) and non-Hispanic White individuals (OR 2.44, 95% CI 1.69-3.51; P < .001) compared to other racial groups.
When researchers separated the cohort based on smoking status, they found current smokers with depression face higher odds for asthma (OR 1.77, 95% CI 1.18-2.65; P = .003) compared with former smokers and never smokers.
“Our study differs from previous literature in that it uses a nationally representative sample and incorporates potential covariates, thus making our findings more generalizable and reliable,” stated Sun and colleagues. “Nonetheless, there are certain limitations that need to be considered when interpreting the results of our study.”
They continued: “Since the NHANES database is a cross-sectional database, it is not possible to distinguish between causal and correlational relationships. Second, although we used statistical techniques to adjust for confounding variables, the possibility of other confounding factors interfering cannot be completely ruled out.”
Source: Sun Y, Zhang Y, Bai W, Liu X. Relationship between depression severity and respiratory symptoms in US adults: A national cross-sectional study. Respir Med. 2023;220:107451. doi:10.1016/j.rmed.2023.107451