Assessing the impact of electronic nicotine delivery systems on chronic obstructive pulmonary disease: A systematic review and meta-analysis.

BACKGROUND

Electronic Nicotine Delivery Systems (ENDS), commonly known as e-cigarettes or vapes, have gained widespread popularity, particularly among young adults and former smokers. While marketed as a harm reduction tool, concerns have emerged regarding their long-term impact on respiratory health, particularly their association with chronic obstructive pulmonary disease (COPD). This systematic review and meta-analysis aimed to evaluate the relationship between ENDS use and COPD risk while considering tobacco smoking as a key confounder.

METHODS

A comprehensive search was conducted across PubMed, Embase, and Web of Science for studies published up to September 20, 2024. Observational studies assessing the association between ENDS use and COPD risk were included. A random-effects meta-analysis was performed using R statistical software (version 4.4). Tobacco smoking, a key confounder in COPD research, was accounted for in many included studies, with adjustments varying across studies.

RESULTS

Fifteen studies met the inclusion criteria. The pooled odds ratio (OR) for current ENDS use and COPD risk was 1.488 (95 % CI: 1.363-1.623). Former ENDS users had an OR of 1.839 (95 % CI: 1.513-2.234), and ever-users had an OR of 1.787 (95 % CI: 1.421-2.247). Sensitivity analyses confirmed the robustness of findings, and no publication bias was detected.

CONCLUSION

This meta-analysis provides evidence of a significant association between ENDS use and increased COPD risk, even after adjusting for tobacco smoking. Future research should standardize smoking adjustments and investigate the independent impact of ENDS use on COPD.