title: Vitamin D status and breast cancer in Saudi Arabian women: case-control study.
abstract: BACKGROUND
  The role of vitamin D in breast cancer prevention is equivocal. Saudi Arabian women may be at greater risk of vitamin D deficiency because of a darker skin type and a greater likelihood of reduced ultraviolet B radiation exposure. Data regarding the vitamin D status of Saudi Arabian women and its relation to breast cancer risk are lacking.
  
  
  OBJECTIVE
  The purpose of this research was to evaluate the association between circulating concentrations of 25-hydroxyvitamin D [25(OH)D] and breast cancer risk in Saudi Arabian women.
  
  
  METHODS
  A case-control study was conducted among 120 breast cancer cases and 120 controls. The study population was drawn from patients admitted to King Fahd Hospital in Jeddah, Saudi Arabia, from June to August 2009. Participants completed questionnaires on diet and medical history, and serum samples were collected from all women to measure circulating 25(OH)D concentrations.
  
  
  RESULTS
  The participants had a mean age of 47.8 y and a mean body mass index (BMI; in kg/m(2)) of 30.0. Breast cancer cases had significantly lower (mean ± SD) serum concentrations of 25(OH)D (9.4 ± 6.4 ng/mL) than did controls (15.4 ± 12.3 ng/mL; P = 0.001). In comparison with those in the highest category of vitamin D status for this population (≥20 ng/mL), the adjusted ORs (95% CIs) for invasive breast cancer were 6.1 (2.4, 15.1) for women with a serum 25(OH)D concentration <10 ng/mL and 4.0 (1.6, 10.4) for women with a serum concentration of ≥10 to <20 ng/mL (P-trend = 0.0001).
  
  
  CONCLUSIONS
  An inverse association exists between serum 25(OH)D concentrations and breast cancer risk in Saudi Arabian women. This trial was registered at clinicaltrials.gov as NCT01817231.
authors.affiliation: Department of Nutritional Sciences, University of Arizona, Tucson, AZ, USA.
authors.forename: Fatimah M
authors.initials: FM
authors.lastname: Yousef
authors.forename: Elizabeth T
authors.initials: ET
authors.lastname: Jacobs
authors.forename: Paul T
authors.initials: PT
authors.lastname: Kang
authors.forename: Iman A
authors.initials: IA
authors.lastname: Hakim
authors.forename: Scott
authors.initials: S
authors.lastname: Going
authors.forename: Jehad M
authors.initials: JM
authors.lastname: Yousef
authors.forename: Rajaa M
authors.initials: RM
authors.lastname: Al-Raddadi
authors.forename: Taha A
authors.initials: TA
authors.lastname: Kumosani
authors.forename: Cynthia A
authors.initials: CA
authors.lastname: Thomson
mesh_terms: D000328:Adult; D015992:Body Mass Index; D001943:Breast Neoplasms / Q000097:blood / Q000453:epidemiology* / Q000517:prevention & control; D016022:Case-Control Studies; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D016015:Logistic Models; D008875:Middle Aged; D009752:Nutritional Status; D015995:Prevalence; D012307:Risk Factors; D012529:Saudi Arabia / Q000453:epidemiology; D011795:Surveys and Questionnaires; D014807:Vitamin D / Q000097:blood*; D014808:Vitamin D Deficiency / Q000097:blood / Q000453:epidemiology*
chemical_list: D014807:Vitamin D