A Arnedo-Pena1, J V Juan-Cerdán2, M Romeu-Garcia3, S Sorribes-Segura4, M Tirado-Balaguer5, M Gil-Fortuño6, D Garcia-Ferrer2, S Sabater-Vidal5, J Iborra-Millet2, A Vizcaino-Batllés3, N Meseguer-Ferrer3, I Vivas-Fornas7, R Moreno-Muñoz5, J B Bellido-Blasco8. 1. Epidemiology Division, Public Health Centre, Castelló de la Plana, Castellon, Department of Health Sciences, Public University of Navarra, Pamplona, Centro de Investigación Biomédica en Red, Epidemiology and Public Health, CIBERESP, Barcelona. 2. Biochemical Laboratory, University Hospital General, Castelló de la Plana, Castellon. 3. Epidemiology Division, Public Health Centre, Castelló de la Plana, Castellon. 4. Medical Care, Municipal Nursing Homes, Almassora and Benicassim, Castellon. 5. Microbiology Laboratory, University General Hospital, Castelló de la Plana, Castellon. 6. Microbiology Laboratory, University La Plana Hospital, Vila-Real, Castellon. 7. Primary Care, Health Centre, El Palleter, Castelló de la Plana, Castellon. 8. Epidemiology Division, Public Health Centre, Castelló de la Plana, Castellon, Centro de Investigación Biomédica en Red, Epidemiology and Public Health, CIBERESP, Barcelona, Department of Epidemiology, Faculty of Medicine, Jaume I University, Castelló de la Plana, Castellon, Spain.
Abstract
OBJECTIVE: To examine the potential association between vitamin D (VitD) deficiency and latent tuberculosis infection (LTBI) and its effect on TB infection conversion (TBIC) incidence. MATERIAL AND METHODS: We carried out a cross-sectional and prospective cohort study of nine pulmonary TB cases that occurred in 2015-2016 in five nursing homes and one mental disability institution in Castellon, Spain. QuantiFERON®-TB Gold and the tuberculin skin test were used to detect LTBI and TBIC, respectively. Serum 25-hydroxyvitamin D was measured using chemiluminescence immunoassay. Poisson regression and inverse probability weighting were used for statistical analyses. RESULTS: The study included 448 residents, 341 staff members with 48 relatives of TB cases (participation rate 82%): of these, respectively 122 (27.2%), 37 (10.9%) and 7 (14.6%) were LTBI-positive; and respectively 22 (7.7%), 10 (3.8%) and 1 (3.7%) were TBIC-positive. LTBI was not associated with VitD status. Severe VitD deficiency (SVDD; defined as VitD level < 10 ng/ml), found in 45.1% of residents, as well as VitD levels of <30 ng/ml (aRR 10.41 95% CI 1.48-73.26), were associated with increased TBIC risk (adjusted relative risk [aRR] 12.1, 95% CI 1.51-97.10), suggesting SVDD as a threshold effect. CONCLUSION: Severe VitD deficiency is a TBIC risk factor.
OBJECTIVE: To examine the potential association between vitamin D(VitD) deficiency and latent tuberculosis infection (LTBI) and its effect on TB infection conversion (TBIC) incidence. MATERIAL AND METHODS: We carried out a cross-sectional and prospective cohort study of nine pulmonary TB cases that occurred in 2015-2016 in five nursing homes and one mental disability institution in Castellon, Spain. QuantiFERON®-TB Gold and the tuberculin skin test were used to detect LTBI and TBIC, respectively. Serum 25-hydroxyvitamin D was measured using chemiluminescence immunoassay. Poisson regression and inverse probability weighting were used for statistical analyses. RESULTS: The study included 448 residents, 341 staff members with 48 relatives of TB cases (participation rate 82%): of these, respectively 122 (27.2%), 37 (10.9%) and 7 (14.6%) were LTBI-positive; and respectively 22 (7.7%), 10 (3.8%) and 1 (3.7%) were TBIC-positive. LTBI was not associated with VitD status. Severe VitD deficiency (SVDD; defined as VitD level < 10 ng/ml), found in 45.1% of residents, as well as VitD levels of <30 ng/ml (aRR 10.41 95% CI 1.48-73.26), were associated with increased TBIC risk (adjusted relative risk [aRR] 12.1, 95% CI 1.51-97.10), suggesting SVDD as a threshold effect. CONCLUSION: Severe VitD deficiency is a TBIC risk factor.