title: Baseline comorbidities in a skin cancer prevention trial in Bangladesh.
abstract: BACKGROUND
  Epidemiologic research suggests that increased cancer risk due to chronic arsenic exposure persists for several decades even after the exposure has terminated. Observational studies suggest that antioxidants exert a protective effect on arsenical skin lesions and cancers among those chronically exposed to arsenic through drinking water. This study reports on the design, methods and baseline analyses from the Bangladesh Vitamin E and Selenium Trial (BEST), a population-based chemoprevention study conducted among adults in Bangladesh with visible arsenic toxicity.
  
  
  METHODS
  Bangladesh Vitamin E and Selenium Trial is a 2 × 2 full factorial, double-blind, randomized controlled trial of 7000 adults having manifest arsenical skin lesions evaluating the efficacy of 6-year supplementation with alpha-tocopherol (100 mg daily) and L-selenomethionine (200 μg daily) for the prevention of nonmelanoma skin cancer.
  
  
  RESULTS
  In cross-sectional analyses, we observed significant associations of skin lesion severity with male gender (female prevalence odds ratio (POR) = 0.87; 95% CI = 0.79-0.96), older age (aged 36-45 years, POR = 1.27; 95% CI = 1.13-1.42; aged 46-55 years, POR = 1.44; 95% CI = 1.27-1.64 and aged 56-65 years, POR = 1.50; 95% CI = 1.26-1.78 compared with aged 25-35 years), hypertension (POR = 1.29; 95% CI = 1.08-1.55), diabetes (POR = 2.13; 95% CI = 1.32-3.46), asthma (POR = 1.55; 95% CI = 1.03-2.32) and peptic ulcer disease (POR = 1.20; 95% CI = 1.07-1.35).
  
  
  CONCLUSIONS
  We report novel associations between arsenical skin lesions with several common chronic diseases. With the rapidly increasing burden of preventable cancers in developing countries, efficient and feasible chemoprevention study designs and approaches, such as employed in BEST, may prove both timely and potentially beneficial in conceiving cancer chemoprevention trials in Bangladesh and beyond.
authors.affiliation: Department of Health Studies, The University of Chicago, Chicago, IL 60637, USA.
authors.forename: Maria
authors.initials: M
authors.lastname: Argos
authors.forename: Mahfuzar
authors.initials: M
authors.lastname: Rahman
authors.forename: Faruque
authors.initials: F
authors.lastname: Parvez
authors.forename: James
authors.initials: J
authors.lastname: Dignam
authors.forename: Tariqul
authors.initials: T
authors.lastname: Islam
authors.forename: Iftekhar
authors.initials: I
authors.lastname: Quasem
authors.forename: Samar
authors.initials: S
authors.lastname: K Hore
authors.forename: Ahmed
authors.initials: A
authors.lastname: T Haider
authors.forename: Zahid
authors.initials: Z
authors.lastname: Hossain
authors.forename: Tazul
authors.initials: T
authors.lastname: I Patwary
authors.forename: Muhammad
authors.initials: M
authors.lastname: Rakibuz-Zaman
authors.forename: Golam
authors.initials: G
authors.lastname: Sarwar
authors.forename: Paul
authors.initials: P
authors.lastname: La Porte
authors.forename: Judith
authors.initials: J
authors.lastname: Harjes
authors.forename: Kristen
authors.initials: K
authors.lastname: Anton
authors.forename: Muhammad G
authors.initials: MG
authors.lastname: Kibriya
authors.forename: Farzana
authors.initials: F
authors.lastname: Jasmine
authors.forename: Rashed
authors.initials: R
authors.lastname: Khan
authors.forename: Mohammed
authors.initials: M
authors.lastname: Kamal
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Shea
authors.forename: Muhammad
authors.initials: M
authors.lastname: Yunus
authors.forename: John A
authors.initials: JA
authors.lastname: Baron
authors.forename: Habibul
authors.initials: H
authors.lastname: Ahsan
mesh_terms: D000328:Adult; D000368:Aged; D016588:Anticarcinogenic Agents / Q000627:therapeutic use*; D000975:Antioxidants / Q000627:therapeutic use*; D020261:Arsenic Poisoning / Q000150:complications*; D001459:Bangladesh; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012645:Selenomethionine / Q000627:therapeutic use*; D012878:Skin Neoplasms / Q000139:chemically induced / Q000517:prevention & control*; D024502:alpha-Tocopherol / Q000627:therapeutic use*
chemical_list: D016588:Anticarcinogenic Agents; D000975:Antioxidants; D012645:Selenomethionine; D024502:alpha-Tocopherol