Cigarette smoking, alcohol intake, and thyroid cancer risk: a pooled analysis of five prospective studies in the United States
We examined the associations between cigarette smoking, alcohol intake, and thyroid cancer risk in a pooled analysis of five prospective studies.
Data from five prospective U.S. studies were standardized and then combined into one aggregate dataset (384,433 men and 361,664 women). Pooled hazard ratios (HR) and 95 % confidence intervals (CI) for thyroid cancer were estimated from mutually adjusted models of cigarette smoking and alcohol intake, which were additionally adjusted for age, sex, education, race, marital status, body mass index, and cohort.
Over follow-up, 1,003 incident thyroid cancer cases (335 men and 668 women) were identified. Compared to never smokers, current smoking was associated with reduced risk of thyroid cancer (HR = 0.68, 95 % CI 0.55–0.85); this association was slightly stronger among non-drinkers (HR = 0.46, 95 % CI 0.29–0.74). No reduction in risk was observed for former, compared to never, smokers. Greater smoking intensity, duration, and pack-years were associated with further reductions in risk among former and current smokers. Alcohol intake was also inversely associated with thyroid cancer risk (≥7 drinks/week versus 0, HR = 0.72, 95 % CI 0.58–0.90, p trend = 0.002). Inverse associations with smoking and alcohol were more pronounced for papillary versus follicular tumors.
The results of this pooled analysis suggest that both cigarette smoking and alcohol consumption are associated with reduced risks of papillary thyroid cancer and, possibly, follicular thyroid cancer.
KeywordsThyroid neoplasms Cigarette smoking Alcohol intake Prospective study Epidemiology
- 1.Howlader N, Noone AM, Krapcho M, Neyman N, Aminou R, Waldron W, et al (Eds) (2011) SEER Cancer Statistics Review, 1975–2008, National Cancer Institute. Bethesda, MD, http://seer.cancer.gov/csr/1975_2008/, based on November 2010 SEER data submission, posted to the SEER web site
- 21.Fritz A, Percy C, Jack A et al (eds) (2000) International classification of diseases for oncology (ICD-O), 3rd edn. WHO, GenevaGoogle Scholar
- 25.National Center for Health Statistics (2012) Health, United States, 2010. Hyattsville, MDGoogle Scholar
- 26.LaVallee RA, Williams GD, Yi H (2011) Surveillance Report #87: Apparent Per Capita Alcohol Consumption: National, State, and Regional Trends, 1970–2007. Bethesda, MD: National Institute on Alcohol Abuse and Alcoholism, Division of Epidemiology and Prevention Research and Health, United States, 2010, National Center for Health Statistics, Hyattsville, MDGoogle Scholar
- 27.Surveillance, Epidemiology, and End Results (SEER) Program. (www.seer.cancer.gov) SEER*Stat Database: Incidence—SEER 9 Regs Research Data, Nov 2011 Sub (1973–2009)—Linked to County Attributes—Total U.S., 1969–2010 Counties, National Cancer Institute, DCCPS, Surveillance Research Program, Surveillance Systems Branch, released April 2012, based on the November 2011 submission
- 28.Surveillance Research Program (2012) National Cancer Institute SEER*Stat software (www.seer.cancer.gov/seerstat) version 7.0.9
- 29.Belin RM, Astor BC, Powe NR, Ladenson PW (2004) Smoke exposure is associated with a lower prevalence of serum thyroid autoantibodies and thyrotropin concentration elevation and a higher prevalence of mild thyrotropin concentration suppression in the third National Health and Nutrition Examination Survey (NHANES III). J Clin Endocrinol Metab 89:6077–6086PubMedCrossRefGoogle Scholar
- 40.Surveillance Epidemiology and End Results (SEER) (2012) SEER stat fact sheet—cancer of the thyroid. Bethesda, MD: National Cancer Institute, National Institutes of Health. http://seer.cancer.gov/csr/1975_2009_pops09/results_single/sect_01_table.11_2pgs.pdf. Accessed July 6 2012