Smoking More Than Doubles Risk of Aortic Dissection, But Quitting Slashes Risk, Study Finds

"In contrast, former smokers showed no significant increase in risk (HR 1.03) and had a 48–75% lower risk than current smokers, highlighting the benefits of quitting," the researchers reported in Scientific Reports. They stressed that while smoking intensity drives up risk, cessation substantially lowers it—underscoring the need for more vigorous public health efforts to curb smoking and promote cessation.

While tobacco smoking raises the risk of aortic dissection, evidence from prospective studies is limited, and the impact of smoking cessation on this risk remains unclear. To address these gaps, Dagfinn Aune, Department of Nutrition, Oslo New University College, Oslo, Norway, and colleagues examined various aspects of tobacco use with aortic dissection within the UK Biobank cohort and further strengthened their findings through a meta-analysis of existing cohort studies.

For this purpose, the researchers investigated the association between various aspects of tobacco smoking and the risk of aortic dissection using data from the UK Biobank Study. They complemented their findings with a meta-analysis of existing cohort studies. In the UK Biobank analysis, multivariable Cox proportional hazards models were employed to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

To identify relevant cohort studies for the meta-analysis, systematic searches were conducted in PubMed and Embase up to July 19, 2024, and summary relative risks (RRs) with 95% CIs were calculated using random effects models.

The study led to the following findings:

• Over a mean follow-up of 12.3 years, 376 new cases of aortic dissection were identified among 499,078 UK Biobank participants.
• Compared to never-smokers, the multivariable-adjusted hazard ratio (HR) was 2.48 (95% CI: 1.87–3.29) for current smokers and 1.03 for former smokers.
• There was a clear dose-response relationship between cigarettes smoked per day and risk of aortic dissection, with HRs of 2.31 for 1–9 cigarettes/day, 2.94 for 10–19, and 2.63 for 20 or more.
• Smoking exposure measured in pack-years also showed a positive association, with an HR of 1.66 for ≥30 pack-years compared to never-smokers.
• Former smokers who had quit for varying durations experienced a 48–75% lower risk of aortic dissection compared to current smokers.
• In the meta-analysis, the summary relative risk (RR) was 2.44 for current smokers and 1.32 for former smokers versus never smokers.
• The risk increased by 52% per 10 cigarettes/day (RR 1.52) and by 16% per 10 pack-years (RR 1.16).
• The risk decreased by 22% per 10 years since quitting smoking (RR 0.78).

“The findings strengthen the evidence that tobacco smoking increases the risk of aortic dissection, with a possible dose-response relationship associated with smoking intensity and duration,” the authors wrote. They further noted that quitting smoking significantly lowers this risk. Concluding their analysis, they emphasized that while further research is warranted, the results reinforce the need for stronger public health initiatives to reduce smoking prevalence and promote cessation.

Reference:

Khan, M. Y., Dillman, A., Hibino, M., & Aune, D. (2025). Tobacco smoking and the risk of aortic dissection in the UK Biobank and a meta-analysis of prospective studies. Scientific Reports, 15(1), 1-10. https://doi.org/10.1038/s41598-025-96529-y