title: High prevalence of vitamin D deficiency in urban health checkup population.
abstract: Vitamin D deficiency is documented as a common health problem in the world. Limited data has been found on the prevalence of vitamin D deficiency in Beijing area.
  
  
  
  To investigate the prevalence s of vitamin D deficiency in urban Beijing residents and the seasonal and monthly serum 25(OH)D variation in this population.
  
  
  
  This is an urban hospital based cross-sectional study lasting whole 2 years. 5531 (5-101 years old) urban Beijing residents for health checkup are recruited from December 9th, 2011 to December 8th, 2013. Each subject completed a questionnaire designed to quantify intake of vitamin D through food, vitamin D supplements, hours of sun exposure, sunscreen use over the past month. Serum 25(OH)D is statistically analyzed in accordance with gender, age, and time-lines.
  
  
  
  Vitamin D deficiency (Serum 25(OH)D level ≤20 ng/mL) and sever deficiency (Serum 25(OH)D level ≤ 10 ng/mL) are highly prevalent in this population. The prevalence of vitamin D deficiency is 87.1% and higher prevalence is found in female (89.0%) than male (84.9% P < 0.001). Severe vitamin D deficiency is also higher in female than male (59.3% and 42.7%, respectively, P < 0.001). Female under 20 and over 80 have lower 25(OH)D levels compared to 40-60 years old female (both P < 0.05). Severe vitamin D deficiency are also highly prevalence in this two group (60.9% and 54.1%) compared with 40-60 years old females (43.1%, both P < 0.05). Seasonal variation are also found in this population (P < 0.01). Autumn and summer have the higher 25(OH)D level than winter and spring in both genders (P < 0.001). Winter and spring have higher vitamin D deficiency and Severe deficiency than the other two seasons (P < 0.05). Serum 25(OH)D level peaks in October and troughed in April in both female and male. Lower serum 25(OH)D level are found in April than February (P < 0.05) in both gender.
  
  
  
  This is the first time to examine the prevalence of vitamin D deficiency among urban Beijing residents spanning the age spectrum. And Vitamin D deficiency and severe deficiency is found highly prevalent in this population, especially among females under 20 and older than 80 and in winter and spring seasons. Targeted prevention on vitamin D deficiency is urgent for this population.
authors.affiliation: Department of Endocrinology and Metabolism, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China. Electronic address: ningzhiwei@hotmail.com.
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Ning
authors.affiliation: Department of Infectious Diseases and Clinical Microbiology, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
authors.forename: Shufan
authors.initials: S
authors.lastname: Song
authors.affiliation: Department of Endocrinology and Metabolism, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
authors.forename: Li
authors.initials: L
authors.lastname: Miao
authors.affiliation: Department of Endocrinology and Metabolism, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
authors.forename: Pengrui
authors.initials: P
authors.lastname: Zhang
authors.affiliation: ACURE Biotechnology, Inc. 8780 Manahan Dr. Ellicott City, MD 21043, USA.
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Endocrinology and Metabolism, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Endocrinology and Metabolism, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
authors.forename: Yanjin
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Department of Endocrinology and Metabolism, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Department of Laboratory Medicine, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Zhao
authors.affiliation: Department of Laboratory Medicine, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
authors.forename: Yufang
authors.initials: Y
authors.lastname: Liang
authors.affiliation: Department of Laboratory Medicine, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
authors.forename: Qingtao
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Pharmacy, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
authors.forename: Lihong
authors.initials: L
authors.lastname: Liu
authors.affiliation: Basic Medical School, Tianjin Medical University, Tianjin 300070, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Basic Medical School, Tianjin Medical University, Tianjin 300070, China.
authors.forename: Lizhi
authors.initials: L
authors.lastname: Hu
authors.affiliation: Affiliate Hospital of Chengde Medical College, Chengde, Hebei Province 67000 China.
authors.forename: Mingyan
authors.initials: M
authors.lastname: Huo
authors.affiliation: Affiliate Hospital of Chengde Medical College, Chengde, Hebei Province 67000 China.
authors.forename: Qinyun
authors.initials: Q
authors.lastname: Zhou
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000068476:Beijing / Q000453:epidemiology; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D013472:Sunlight; D011795:Surveys and Questionnaires; D014504:Urban Health; D014505:Urban Population; D014807:Vitamin D / Q000008:administration & dosage / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000453:epidemiology*; D055815:Young Adult
chemical_list: D014807:Vitamin D
keywords: 25-hydroxy vitamin D; Chinese; Prevalence; Season; Vitamin D; Vitamin D deficiency