Smoking significantly increases risk of major bleeding
In a new study, researchers have found that smoking significantly increases the risk of major bleeding. The risk of major bleeding was found to be statistically significant across all subtypes of bleeding (ie, intracranial, airway, gastrointestinal, urinary). The study has appeared in the Journal Thrombosis and Haemostasis.
Tobacco smoking represents the most preventable cause of several fatal and disabling diseases worldwide. Several ingredients in tobacco have been suspected to cause changes in the arterial wall leading to instability of blood vessels. The association of smoking with major bleeding is largely unexplored.
The researchers conducted a prospective cohort study with a mean follow-up of 5.9 years including 99,359 individuals from the Copenhagen General Population Study, with a questionnaire including self-reported smoking status and information on smoking intensity in cigarettes per day and pack-years. In this study, 17,555 were current smokers, 40,182 former smokers and 41,622 were never smokers.
In the study multivariable-adjusted hazard ratios found for current smokers versus never smokers were 1.49 (95% confidence interval [CI]: 1.38-1.61) for any major bleeding, 1.71 (1.37-2.13) for intracranial bleeding, 1.35 (1.14-1.60) for airway bleeding, 2.20 (1.84-2.62) for gastrointestinal bleeding and 1.39 (1.26-1.55) for urinary bleeding. Increased smoking intensity was also associated with increased risk of any major bleeding, where > 40 pack-years in current and former smokers compared with never smokers had a multivariable-adjusted hazard ratio of 1.59 (95% CI: 1.45-1.73) (p for trend across four groups: < 0.001). Also, current smokers smoking > 20 cigarettes per day compared with former and never smokers had a corresponding hazard ratio of 1.67 (1.51-1.85) (p for trend across four groups: < 0.001).
The researchers concluded that current smokers have an increased risk of any major bleeding as well as of intracranial, airway, gastrointestinal and urinary bleeding. Also, the increased smoking intensity was associated with an increased risk of major bleeding.
This prospective study tested the hypothesis that smoking and high consumption of tobacco are associated with an increased risk of major bleeding. Among the total 99,359 patients with mean 5.9 years of follow-up, current smokers were more likely than never smokers to have episodes of major bleeding in a multivariable analysis.