title: Vitamin D deficiency is a problem for adult out-patients? A university hospital sample in Istanbul, Turkey.
abstract: OBJECTIVE
  To investigate the frequency of vitamin D deficiency in relation to demographics, clinical diagnosis, season of measurement and laboratory parameters in adult out-patients.
  
  
  METHODS
  Descriptive, retrospective study concerning evaluation of the initial 25-hydroxyvitamin D (25(OH)D) levels determined at admission in relation to demographics, clinical diagnosis, season of measurement and laboratory parameters. 25(OH)D levels ,20 ng/ml were classified as deficiency, 20–30 ng/ml as insufficiency and .30 ng/ml as sufficiency.
  
  
  METHODS
  Out-patient clinics at a tertiary care centre.
  
  
  METHODS
  A total of 2488 adult patients (mean age: 53?3 (SD 15?2) years; 85?2% were females) admitted to out-patient clinics at Baskent University Istanbul Hospital were included.
  
  
  RESULTS
  Mean level of 25(OH)D in the overall population was 17?4 (SD 11?5) ng/ml while insufficiency and deficiency were evident in 24% and 66% of patients, respectively. Mean 25(OH)D levels in males .45 years old were higher than in their female counterparts (19?4 (SD 11?3) ng/ml v. 17?8 (SD 12?2) ng/ml; P,0?05). Mean 25(OH)D levels obtained in summer (18?6 (SD 11?1) ng/ml) and autumn (23?3 (SD 13?6) ng/ml) were significantly higher than levels in spring (16?1 (SD 10?3) ng/ml) and winter (14?6 (SD 10?2) ng/ml; P,0?01). Mean 25(OH)D levels were determined to be significantly lower in obese patients compared with non-obese patients (15?6 (SD 10?4) ng/ml v. 17?6 (SD 11?6) ng/ml; P,0?05). Levels of 25(OH)D were significantly negatively correlated with serum parathyroid hormone levels (r520?194; P,0?001) while significantly positively correlated with phosphorus (r50?059; P,0?01) and HDL cholesterol (r50?070; P,0?01) levels.
  
  
  CONCLUSIONS
  Our findings indicate that vitamin D deficiency is very common among out-patients in Turkey, regardless of gender and age, especially among obese people and during winter and spring.
authors.affiliation: Faculty of Medicine, Department of Family Medicine, Baskent University, Ankara, Turkey. ozlemcigerli@gmail.com
authors.forename: Ozlem
authors.initials: O
authors.lastname: Cigerli
authors.forename: Hulya
authors.initials: H
authors.lastname: Parildar
authors.forename: Aslı D
authors.initials: AD
authors.lastname: Unal
authors.forename: Ozlem
authors.initials: O
authors.lastname: Tarcin
authors.forename: Rengin
authors.initials: R
authors.lastname: Erdal
authors.forename: Nilgun
authors.initials: N
authors.lastname: Guvener Demirag
mesh_terms: D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000032:analysis; D002097:C-Reactive Protein / Q000032:analysis / Q000378:metabolism; D002118:Calcium / Q000097:blood; D002784:Cholesterol / Q000097:blood; D003404:Creatinine / Q000097:blood; D005215:Fasting; D005260:Female; D006785:Hospitals, University; D006801:Humans; D007328:Insulin / Q000097:blood; D008297:Male; D008875:Middle Aged; D017711:Nonlinear Dynamics; D009765:Obesity / Q000097:blood; D010045:Outpatients; D010281:Parathyroid Hormone / Q000097:blood; D010758:Phosphorus / Q000097:blood; D012189:Retrospective Studies; D012621:Seasons; D014280:Triglycerides / Q000097:blood; D014421:Turkey / Q000453:epidemiology; D014808:Vitamin D Deficiency / Q000097:blood* / Q000453:epidemiology*
chemical_list: D001786:Blood Glucose; D007328:Insulin; D010281:Parathyroid Hormone; D014280:Triglycerides; D010758:Phosphorus; D002097:C-Reactive Protein; D002784:Cholesterol; D003404:Creatinine; D002118:Calcium