title: Vitamin D status and incidence of tuberculosis infection conversion in contacts of pulmonary tuberculosis patients: a prospective cohort study.
abstract: The objective of this study was to estimate the relationship between serum vitamin D (VitD) status and tuberculosis (TB) infection conversion (TBIC), measured by the tuberculin skin test (TST) and an interferon-gamma release assay, the QuantiFERON-TB Gold In-Tube (QFT-GIT) test, in the contacts of pulmonary TB patients in Castellon (Spain) in a prospective cohort study from 2010 to 2012. Initially, the participants were negative to latent TB infection after a screening that included TST and QFT-GIT tests, and other examinations. A baseline determination of 25-hydroxyvitamin D [25(OH)D] was obtained by chemiluminescence immunoassay. After 8-10 weeks, participants were screened for a second time to determine TB infection conversion (TBIC). Poisson regression models were used in the statistical analysis. Of the 247 participants in the cohort, 198 (80·2%) were screened twice and 18 (9·1%) were TBIC cases. The means of VitD concentration in the TBIC cases and the non-cases were 20·7±11·9 and 27·2±11·4 ng/ml (P = 0·028), respectively. Adjusted for high exposure and TB sputum acid-fast bacilli (AFB)-positive index case, higher serum VitD concentration was associated with low incidence of TBIC (P trend = 0·005), and an increase of 1 ng/ml VitD concentration decreased the incidence of TBIC by 6% (relative risk 0·94, 95% confidence interval 0·90-0·99, P = 0·015). The results suggest that sufficient VitD level could be a protective factor of TBIC.
authors.affiliation: Epidemiology Division,Public Health Centre,Castellón,Spain.
authors.forename: A
authors.initials: A
authors.lastname: Arnedo-Pena
authors.affiliation: Biochemical Laboratory,Hospital General,Castellón,Spain.
authors.forename: J V
authors.initials: JV
authors.lastname: Juan-Cerdán
authors.affiliation: Epidemiology Division,Public Health Centre,Castellón,Spain.
authors.forename: M A
authors.initials: MA
authors.lastname: Romeu-García
authors.affiliation: Biochemical Laboratory,Hospital General,Castellón,Spain.
authors.forename: D
authors.initials: D
authors.lastname: García-Ferrer
authors.affiliation: Preventive Medicine,Hospital La Plana,Vila-real,Spain.
authors.forename: R
authors.initials: R
authors.lastname: Holguín-Gómez
authors.affiliation: Biochemical Laboratory,Hospital General,Castellón,Spain.
authors.forename: J
authors.initials: J
authors.lastname: Iborra-Millet
authors.affiliation: Microbiology Laboratory,Hospital General,Castellón,Spain.
authors.forename: F
authors.initials: F
authors.lastname: Pardo-Serrano
mesh_terms: D000328:Adult; D015331:Cohort Studies; D005260:Female; D006801:Humans; D059425:Interferon-gamma Release Tests; D055985:Latent Tuberculosis / Q000453:epidemiology / Q000276:immunology / Q000635:transmission*; D008297:Male; D008875:Middle Aged; D016012:Poisson Distribution; D011446:Prospective Studies; D012044:Regression Analysis; D012307:Risk Factors; D014374:Tuberculin Test; D014376:Tuberculosis / Q000453:epidemiology / Q000276:immunology / Q000635:transmission; D014397:Tuberculosis, Pulmonary / Q000453:epidemiology / Q000276:immunology / Q000635:transmission*; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000453:epidemiology*
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: vitamin D