The association between alcohol consumption and pulmonary function: a scoping review.

Introduction: The health effects of alcohol are well established but the influence on pulmonary function remains debated. Studies indicate that small amounts of alcohol are beneficial and heavy consumption is harmful, suggesting a U-shaped association. Our objective is to determine whether there is an association between alcohol intake and changes in pulmonary function parameters, exploring the potential protective effect of moderate alcohol consumption and the harm caused by heavy drinking.

Methods: A comprehensive search from PubMed, Embase, Cochrane and CINAHL was carried out, and studies were evaluated using the JBI methodological framework for scoping reviews. Two independent reviewers conducted parallel screening and data extraction. A data extraction form was utilised to organise key themes, with qualitative analysis and visual representation of the results.

Results: Among 4427 screened abstracts, 179 underwent full-text review, resulting in 30 eligible studies. Of these, 10 showed a negative effect, nine reported no impact, nine exhibited a positive effect and two indicated a nonlinear U-shaped association between alcohol consumption and pulmonary function parameters.

Conclusion: While the U-shaped curve hypothesis remains unconfirmed by the current literature, there are notable associations. Heavy alcohol consumption appears to negatively affect pulmonary function, while low to moderate intake shows a positive influence in included studies. However, the diversity in study quality, the nonstandardised alcohol intake quantification and the confounding role of smoking challenge definitive conclusions. The need for consistent, long-term international studies is evident to further explore this relationship while addressing the complex interplay between alcohol and smoking.