American Journal of Epidemiology Advance Access originally published online on May 15, 2008
American Journal of Epidemiology 2008 168(2):158-169; doi:10.1093/aje/kwn109
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ORIGINAL CONTRIBUTIONS |
Body Mass Index and Waist Circumference in Relation to Lung Cancer Risk in the Women's Health Initiative
1 Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Yeshiva University, Bronx, NY
2 Women's Health Initiative Clinical Coordinating Center, Fred Hutchinson Cancer Research Center, Seattle, WA
3 Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, CA
Correspondence to Dr. Geoffrey C. Kabat, Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Yeshiva University, Belfer Building, Room 1301, 1300 Morris Park Avenue, Bronx, NY 10461 (e-mail address: gkabat{at}aecom.yu.edu).
Received for publication October 2, 2007. Accepted for publication April 1, 2008.
Investigators in several epidemiologic studies have observed an inverse association between body mass index (BMI) and lung cancer risk, while others have not. The authors used data from the Women's Health Initiative to study the association of anthropometric factors with lung cancer risk. Over 8 years of follow-up (1998–2006), 1,365 incident lung cancer cases were ascertained among 161,809 women. Cox proportional hazards models were used to estimate hazard ratios adjusted for covariates. Baseline BMI was inversely associated with lung cancer in current smokers (highest quintile vs. lowest: hazard ratio (HR) = 0.62, 95% confidence interval (CI): 0.42, 0.92). When BMI and waist circumference were mutually adjusted, BMI was inversely associated with lung cancer risk in both current smokers and former smokers (HR = 0.40 (95% CI: 0.22, 0.72) and HR = 0.61 (95% CI: 0.40, 0.94), respectively), and waist circumference was positively associated with risk (HR = 1.56 (95% CI: 0.91, 2.69) and HR = 1.50 (95% CI: 0.98, 2.31), respectively). In never smokers, height showed a borderline positive association with lung cancer. These findings suggest that in smokers, BMI is inversely associated with lung cancer risk and that waist circumference is positively associated with risk.
adiposity; body mass index; body weight changes; health status; lung neoplasms; smoking; waist-hip ratio
Abbreviations: BMI, body mass index; CI, confidence interval; HR, hazard ratio; WHI, Women's Health Initiative