A systematic review and meta-analysis of the association between HIV and MDR-TB
Every year, the month of March is designated as tuberculosis (TB) month. The contribution by AfroAIDSinfo is to present a short summary of a systematic review and meta-analysis, conducted to test the statistical significance of the association between HIV and TB.
Researchers from three Ethiopian universities set out to study the association between the human immune deficiency virus (HIV) and multi-drug resistant tuberculosis (MDR-TB), because of the widespread prevalence of HIV and Mycobacterium tuberculosis, which causes TB, in sub-Saharan Africa (Mesfin et al., 2014).
The researchers sourced studies from three databases (Medline/PubMed, Google Scholar, and the Health Inter Network Access to Research Initiative (HINARI)) along with a manual search of the International Journal of Tuberculosis and Lung Disease. The following key words were included in the retrieval of studies from the online databases: “MDR-TB”, “HIV/AIDS”, “drug resistance”, and “multidrug resistance”. The authors searched for observational studies which included cross-sectional, surveillance, case-control and cohort studies that reported on the association between HIV and MDR-TB. Mycobacterium tuberculosis strains resistant to rifampicin and isoniazid were classified as MDR-TB strains.
The quality of the data of the studies was assessed with pre-formatted standardised data extraction forms by the first and second authors. Studies were excluded when no measure of association (odds ratio or relative risk) were reported or when a study was conducted on a type of TB other than pulmonary TB.
Ultimately, 24 studies were subjected to Der Simonian Laird random-effects meta-analysis and measurement of odds ratio with 95% confidence interval to determine the overall effect that HIV infection has on MDR-TB. Funnel plots based on Begg rank correlation and Egger-weighted regression tests were used to determine publication bias. The investigators used Cochran’s Q test to evaluate statistical heterogeneity. Cochran’s Q test determines the influence of chance on heterogeneity between studies. I2 test was used to determine the magnitude of this statistical heterogeneity.
Conflicting results were obtained from these statistical tests. The Egger-weighted regression test showed publication bias (p = 0.02) while Begg’s rank correlation test showed none (p = 0.33). The Cochran’s Q test indicated a good homogeneity (p = 0.181) in contrast to the low homogeneity (I2 = 19.6%) revealed by the I2 test.
In this study it was demonstrated that the probability of encountering MDR-TB among people living with HIV/AIDS is statistically significant, as indicated by a pooled odds ratio of 1.24 (95% CI 1.04-1.43). The pooled odds ratio was determined by Der Simonian Laird random-effects meta-analysis. The summary odds ratio of 2.28 (95% CI 1.52-3.04)also confirmed this.
This study affirmed the increased risk of MDR-TB in HIV-infected individuals even though it was subject to publication bias and bias in its pooled estimate. The authors did not give a reason for why they excluded effects measurements of extra-pulmonary TB from their study even though HIV-infected individuals are more vulnerable to developing the condition (Naing et al., 2013). In light of their findings, the authors recommend that health systems be strengthened to prevent loss to follow-up, detect MDR-TB early, and initiate antiretroviral therapy in people living with HIV early, whereby the spread and development of MDR-TB can be prevented.
You may read the entire article here.
- Mesfin, Y. M., Hailermariam, D., Biadgilign, S., and Kibret, K. T. (2014) ‘Association between HIV/AIDS and multi-drug resistance tuberculosis: A systematic review and meta-analysis’ [Online] PloS One 9, e82235.
- Naing, C., Mak, J. W., Maung, M., Wong, S. F., and Kassim, A.I. (2013) ‘Meta-analysis: the association between HIV infection and extrapulmonary tuberculosis’ Lung 191, 27-34.
Author: Waldo Adams
Reviewed by: Hendra van Zyl (MPH), Jean Fourie (MPhil) and Michelle Moorhouse (MBBCh, DA)
Date: April 2014
Adams, W. (2014) A systematic review and meta-analysis of the association between HIV and MDR-TB, AfroAIDSinfo. Issue 14 no. 4, Science (Open access).
2 April, 2014