title: Serum 25-hydroxyvitamin D in a West African population of tuberculosis patients and unmatched healthy controls.
abstract: BACKGROUND
  Little is known regarding vitamin D deficiency (VDD) in African populations and in tuberculosis (TB) patients. VDD has been shown to be associated with TB.
  
  
  OBJECTIVE
  We aimed to compare the degree of vitamin D insufficiency (VDI) and VDD in TB patients and healthy adult controls in a West African population.
  
  
  METHODS
  An unmatched case-control study was performed at a Demographic Surveillance Site in Guinea-Bissau. Serum 25-hydroxyvitamin D(3) [25(OH)D(3)] concentrations were measured in 362 TB patients and in 494 controls.
  
  
  RESULTS
  Hypovitaminosis D [25(OH)D(3) </= 75 nmol/L] was more common in TB patients, but VDD [25(OH)D(3) </= 50 nmol/L] was more common and more severe in controls. We observed hypovitaminosis D in 46% (167/362) of the TB patients and in 39% (193/494) of the controls; the relative risk (RR) of hypovitaminosis D was 1.18 (95% CI: 1.01, 1.38). VDD was observed in 8.5% (31/362) of the TB patients and in 13.2% (65/494) of the controls. The RR was 0.65 (95% CI: 0.43, 0.98), mainly because severe VDD [25(OH)D(3) </= 25 nmol/L] was observed in only 1 of 362 TB patients (0.2%) and in 24 of 494 controls (4.9%). After adjustment for background factors, hypovitaminosis D was not more frequent in TB patients than in healthy controls, but the mean serum 25(OH)D(3) concentration remained lower.
  
  
  CONCLUSIONS
  Hypovitaminosis D was highly prevalent in TB patients and in healthy controls living at 12 degrees N; severe VDD was rare in TB patients. The finding indicates that the serum 25(OH)D(3) concentration is associated with TB infection, but whether this role is a symptom or is causal was not established.
authors.affiliation: Bandim Health Project, INDEPTH Network, Statens Serum Institut, Bissau, Guinea-Bissau, University of Copenhagen, Copenhagen, Denmark. wejse@dadlnet.dk
authors.forename: Christian
authors.initials: C
authors.lastname: Wejse
authors.forename: Rikke
authors.initials: R
authors.lastname: Olesen
authors.forename: Paulo
authors.initials: P
authors.lastname: Rabna
authors.forename: Pernille
authors.initials: P
authors.lastname: Kaestel
authors.forename: Per
authors.initials: P
authors.lastname: Gustafson
authors.forename: Peter
authors.initials: P
authors.lastname: Aaby
authors.forename: Paul L
authors.initials: PL
authors.lastname: Andersen
authors.forename: Henning
authors.initials: H
authors.lastname: Glerup
authors.forename: Morten
authors.initials: M
authors.lastname: Sodemann
mesh_terms: D000328:Adult; D000354:Africa, Western / Q000453:epidemiology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D015995:Prevalence; D014376:Tuberculosis / Q000097:blood*; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000453:epidemiology*
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D