China: In a groundbreaking study involving over 280,000 participants, researchers have discovered a significant association between lung function and the onset of depression. This prospective cohort study sheds light on the intricate biological pathways linking respiratory health to mental well-being.
The study, published in BMC Medicine, revealed that the higher risk of depression development was associated with impaired lung function. Moreover, the association might be mediated partially by biomarkers, including erythrocytes, systemic inflammation, and renal and liver function.
"In a cohort of patients with varying lung function assessed through values of forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1), and no previous depression, participants with the lowest lung function had increased depression levels versus individuals with better levels of lung function," the researchers reported.
Lung health is increasingly being recognized as an important factor in mental health. However, there is a need to determine prospective evidence on lung function with incident depression. Considering this, Bao-Peng Liu, Cheeloo College of Medicine, Shandong University, Jinan, China, and colleagues aimed to examine the prospective association between impaired lung function and incident depression and the underlying biological mechanisms.
The prospective cohort study enrolled 280,032 non-depressed individuals with valid lung function measurements from the UK Biobank. Lung function assessment was done through FVC or FEV1. The associations between lung function and incident depression were estimated using Cox proportional hazard models. Mediation analyses were fitted to examine the potential mediating role of metabolites and biomarkers in the association.
The study led to the following findings:
· During a median follow-up of 13.91 years, 3.4% of participants developed depression.
· Individuals in the highest quartile had a lower risk of depression (FVC % predicted: HR = 0.880; FEV1% predicted: HR = 0.854) compared with those in the lowest quartile of the lung function indices.
· The restricted cubic splines suggested lung function indices had reversed J-shaped associations with incident depression.
· Impaired lung function yielded similar risk estimates (HR = 1.124).
· Biomarkers involving systemic inflammation, erythrocytes, and liver and renal function may be potential mediators in the lung function-depression association.
In conclusion, the study revealed an association between impaired lung function and an increased risk of developing depression. Regular lung function screening in routine practice holds the potential to identify at-risk populations and the development of personalized interventions, yielding profound public and clinical health implications.
"Our findings underscored that the biomarkers involving erythrocytes, systemic inflammation, and renal and liver function may partially mediate this association, but these mediation findings should be interpreted with caution due to potential temporal ambiguity," the researchers wrote. "Further studies are warranted with repeatedly measured data to replicate our mediation findings."
Reference:
Hu, W., Liu, BP. & Jia, CX. Association and biological pathways between lung function and incident depression: a prospective cohort study of 280,032 participants. BMC Med 22, 160 (2024). https://doi.org/10.1186/s12916-024-03382-3