Environmental tobacco smoke exposure increases Mycobacterium tuberculosis infection risk in children

• Published in: The international journal of tuberculosis and lung disease Vol. 15; no. 11; pp. 1490 - 1497
• Main Authors: du Preez, K., Mandalakas, Kirchner, Grewal, Schaaf, van Wyk, Hesseling
• Format: Journal Article
• Language: English
• Published: Paris International Union Against Tuberculosis and Lung Disease 01-11-2011; International Union against Tuberculosis and Lung Disease
• Subjects: Adolescent; Age Factors; Bacterial diseases; Biological and medical sciences; Chi-Square Distribution; Child; Child, Preschool; Children; Cross-Sectional Studies; Environmental Exposure; ETS; Female; Human bacterial diseases; Human immunodeficiency virus; Humans; Infant; Infection; Infectious diseases; Logistic Models; Male; Medical sciences; Mycobacterium tuberculosis; Mycobacterium tuberculosis - pathogenicity; Odds Ratio; Pneumology; Prevalence; Prospective Studies; Respiratory system : syndromes and miscellaneous diseases; Risk Assessment; Risk Factors; South Africa - epidemiology; Surveys and Questionnaires; Time Factors; Tobacco Smoke Pollution - adverse effects; Tuberculin Test; Tuberculosis; Tuberculosis - diagnosis; Tuberculosis - epidemiology; Tuberculosis - etiology; Tuberculosis - microbiology; Tuberculosis and atypical mycobacterial infections; South Africa; Human; Tobacco smoke; Respiratory disease; ETS; Risk; Increase; Exposure; Mycobacterial infection; Infection; Tuberculosis; Mycobacterium tuberculosis; Mycobacteriales; children; Risk factor; Bacteriosis; Mycobacteriaceae; Bacteria; Actinomycetes; Child; Pneumology
• ISSN: 1027-3719; 1815-7920
• DOI: 10.5588/ijtld.10.0759

BACKGROUND: Data on the association between exposure to environmental tobacco smoke (ETS) and Mycobacterium tuberculosis infection in children are limited. OBJECTIVE: To examine the dose-response effect of ETS exposure on the risk of M. tuberculosis infection in children
in a high tuberculosis (TB) burden setting. METHODS: This cross-sectional study included healthy South African children from impoverished urban communities. Data were collected on household ETS and M. tuberculosis exposure, demographics, socio-economic and anthropometric data, M.
tuberculosis infection, human immunodeficiency virus and TB disease status. RESULTS: Among 196 children (median age 6.8 years, range 0.3-15.9), 97 (49.5%) were M. tuberculosis - i nfected (tuberculin skin test [TST] ≥ 10 mm) and 128 (65.3%) reported ETS exposure; of these,
81/128 (63.3%) were exposed to ≥ 2 household smokers. The presence of ≥ 2 household smokers was associated with M. tuberculosis infection in univariate analysis, irrespective of TST cut-off point. In analysis adjusting for M. tuberculosis exposure, socio-economic status,
age and previous TB treatment, ETS exposure remained associated with M. tuberculosis infection. In univariate and multivariate analysis, pack-years of exposure were associated with risk of TB infection. DISCUSSION: Exposure to ETS is associated with M. tuberculosis infection
in children after adjustment for multiple variables, with a dose-response relationship between the degree of ETS exposure and risk of infection. Public health interventions to reduce exposure to tobacco smoke among children in high TB burden settings are urgently needed.