Weight Gain After Smoking Cessation and Cancer Risk in 3 Prospective Cohorts in the United States
Menée à partir de données 1978-2016 des cohortes "the Nurses’ Health Studies" et "the Health Professionals Follow-Up Study" portant sur 198 565 personnes, cette étude analyse l'association entre une prise de poids après un sevrage tabagique et le risque de cancer (32 456 cas)
It remains unknown how cancer risks vary by duration of smoking cessation and whether the benefit is attenuated by post-cessation weight gain.We prospectively followed 198,565 persons from Nurses’ Health Study (NHS, 1978-2016), NHSII (1991-2017), and Health Professionals Follow-up Study (1988-2016) who were free of cancer at baseline. We used proportional hazard Cox models to compare cancer risk between current smokers and former smokers with different durations of smoking cessation and post-cessation weight gains.During 4,718,199 person-years of follow-up, we identified 32,456 cases of total cancer. Compared to current smokers, the risks for total and smoking-related cancer in past smokers were reduced to the level similar to never smokers after abstaining smoking for more than 26 years, with the hazard ratio of 0.69 (95% confidence interval [CI] = 0.63,0.76) for total cancer and 0.31 (95% CI = 0.26,0.37) for smoking related cancer, whereas no risk reduction was found for obesity-related cancer. Comparing former smokers to current smokers, the multivariable-adjusted hazard ratios for post-cessation weight gain of 0-5 kg, >5-10 kg, and ≥10 kg were 0.85 (95% CI = 0.81,0.89), 0.88 (95% CI = 0.83,0.93), and 0.93 (95% CI = 0.88,1.00) for total cancer; and 0.62 (95% CI = 0.58,0.67), 0.65 (95% CI = 0.60,0.71), and 0.71 (95% CI = 0.65,0.78) for total smoking-related cancer. In contrast, higher weight gain following smoking cessation was associated with a modest increased obesity-related cancer risk.Smoking cessation overall has a strong net association with lower risk of total cancer irrespective of weight gain. However, this inverse association may be attenuated by substantial post-cessation weight gain, largely due to an increased risk of obesity-related cancers.
JNCI Cancer Spectrum 2022