Risk factors for tuberculosis in foreign-born people (FBP) in Italy: a systematic review and meta-analysis

In Italy, TB notifications in foreign-born people (FBP) are steadily increasing. To investigate this issue we did a meta-analysis on risk factors for FBP people. A systematic search was performed in PubMed and EMBASE from Jan-1980 to Jan-2013. We analysed HIV status, previous TB-treatment, intravenous drug use and alcohol abuse, and multidrug resistant TB. Odd ratio was used as a measure of effect. One and two-stages approaches were used. In the main analysis we used a 2-stages approach to include studies with only aggregate estimates. Among 1996 references, 18 fulfilled inclusion criteria. In TB-affected FBP people positive HIV-status was about 3 times higher than among Italians, after 1996 when combined antiretroviral therapy for HIV was introduced (OR: 2.91; 95%CI: 1.37; 6.17). No association was found between FBP and intravenous drug users in adults; after 1-stage meta-analysis foreign born people from highly endemic countries had a 4 times higher risk to be multidrug resistant TB than Italian people. Finally, TB-affected FBP were less likely than Italians to be alcoholics (OR: 0.10 95%CI: 0.01; 0.84) or of having received previous TB-treatment (OR: 0.55; 95%CI: 0.43; 0.71). An association of multidrug resistant TB with immigrant status as well as an association of Tuberculosis with HIV-positive status in foreign-born people are major findings of this analysis. Drugs and alcohol abuse do not appear to be risk factors for TB in FBP, however they cannot be discharged since may depend on cultural traditions and their role may change in the future along with the migratory waves. An effective control of TB risk factors among migrants is crucial to obtain the goal of TB eradication.