Smoking Cessation and the Risk of Bladder Cancer among Postmenopausal Women

• Published in: Cancer prevention research (Philadelphia, Pa.) Pa.), 2019-05, Vol.12 (5), p.305-314
• Main Authors: Li, Yueyao, Tindle, Hilary A, Hendryx, Michael S, Xun, Pengcheng, He, Ka, Liang, Xiaoyun, Luo, Juhua
• Format: Article
• Language: English
• Subjects: Aged; Carcinoma, Papillary - epidemiology; Carcinoma, Papillary - etiology; Carcinoma, Papillary - pathology; Carcinoma, Papillary - prevention & control; Carcinoma, Transitional Cell - epidemiology; Carcinoma, Transitional Cell - etiology; Carcinoma, Transitional Cell - pathology; Carcinoma, Transitional Cell - prevention & control; Ex-Smokers - statistics & numerical data; Female; Follow-Up Studies; Humans; Incidence; Middle Aged; Non-Smokers - statistics & numerical data; Postmenopause; Prospective Studies; Risk Factors; Smokers - statistics & numerical data; Smoking Cessation - statistics & numerical data; Time Factors; Tobacco Smoking - adverse effects; Urinary Bladder - pathology; Urinary Bladder Neoplasms - epidemiology; Urinary Bladder Neoplasms - etiology; Urinary Bladder Neoplasms - pathology; Urinary Bladder Neoplasms - prevention & control
• ISSN: 1940-6207; 1940-6215; 1940-6215
• DOI: 10.1158/1940-6207.CAPR-18-0441

Smoking is the strongest established risk factor for bladder cancer. Former smokers have a lower risk of bladder cancer compared with current smokers, but findings on the dose-response relationship between years after quitting and the risk of bladder cancer are inconsistent. A total of 143,279 postmenopausal women from the Women's Health Initiative Study were included. Cox proportional hazards regression models were applied for estimating age- and multivariable-adjusted HRs and their 95% confidence intervals (CI). There were 870 bladder cancer cases identified over an average of 14.8 years of follow-up. After adjusting for pack-years of smoking, bladder cancer risk among former smokers declined by 25% within the first 10 years of cessation and continued to decrease as cessation time increased but remained higher than never smokers after 30 years of quitting (HR, 1.92; 95% CI, 1.43-2.58). Smokers who quit smoking had a lower risk of bladder cancer compared with current smokers (HR, 0.61; 95% CI, 0.40-0.94). We conclude that among postmenopausal women, there is a significant reduction in the risk of bladder cancer after quitting smoking. In addition to primary prevention, smoking cessation is critical to prevent the incidence of bladder cancer in older women.