Converging risk factors but no association between HIV infection and multidrug-resistant tuberculosis in Kazakhstan

Abstract

Kazakhstan is a country with a low HIV/AIDS (human immunodeficiency virus/acquired immune-deficiency syndrome) burden, but a high prevalence of multidrug-resistant tuberculosis (MDR-TB). We describe the epidemiology of multidrug resistance and HIV among TB patients, using the 2007-2011 national electronic TB register. HIV test results were available for 97.2% of TB patients. HIV prevalence among TB patients increased from 0.6% in 2007 to 1.5% in 2011. Overall, 41.6% of patients had a positive smear at diagnosis, 38.6% a positive culture and 51.7% either a positive smear or culture. Drug susceptibility testing (DST) results were available for 92.7% of culture-positive cases. Socio-economic factors independently associated with both HIV and MDR-TB were urban residency, drug use, homelessness and a history of incarceration. In adjusted analysis, HIV positivity was not associated with MDR-TB (OR 1.0, 95%CI 0.86-1.2). Overall, among TB patients with DST and HIV test results available, 65.0% were positive for neither HIV nor MDR-TB, 33.5% only for MDR-TB, 0.9% only for HIV and 0.6% for both HIV and MDR-TB. Among injection drug users, 12.5% were positive for HIV and MDR-TB. We showed increasing HIV prevalence among TB patients in Kazakhstan. HIV was not an independent risk factor for MDR-TB, but risk factors were largely overlapping and we did identify subgroups at particular risk of HIV-MDR-TB co-infection, notably drug users. Enhanced efforts are necessary to provide care to these socially vulnerable populations.