Indoor solid fuel combustion and tuberculosis: is there an association?

OBJECTIVES

To assess the strength of evidence in published articles for an association between indoor solid fuel combustion and tuberculosis.

METHODS

PubMed, a private database and Google Scholar were searched up to May 2008, as was the Cochrane Library (2008, issue 4), to identify articles on the association between indoor air pollution and tuberculous infection, tuberculosis disease and tuberculosis mortality. Each article initially chosen as acceptable for inclusion was reviewed for data extraction by three different reviewers using a standard format. Strength of evidence was determined by pre-determined criteria.

RESULTS

The full texts of 994 articles were examined for a final selection of 10 possible articles, of which six met the inclusion criteria. All articles investigated the association between exposure to solid fuel (coal and biomass) smoke and tuberculosis disease. Three (50%) of the six studies included in the systematic review showed a significant effect of exposure to solid fuel combustion and tuberculosis disease-one high-quality case-control study and two cross-sectional studies.

CONCLUSION

Despite the plausibility of an association, available original studies looking at this issue do not provide sufficient evidence of an excess risk of tuberculosis due to exposure to indoor coal or biomass combustion. Because the number of studies identified was small, new studies are needed before more definitive conclusions can be reached.