Rates of emergence of HIV drug resistance in resource-limited settings: a systematic review

University of California, San Diego, San Diego, CA, USA.
Antiviral therapy (Impact Factor: 3.14). 10/2012; 18(1). DOI: 10.3851/IMP2437
Source: PubMed

ABSTRACT BACKGROUND: The increasing availability of antiretroviral therapy (ART) has improved survival and quality of life for many infected with HIV, but can also engender drug resistance. This review summarizes the available information on drug-resistance in adults in resource-limited settings (RLSs). METHODS: The online databases PubMed and Google Scholar, pertinent conference abstracts, and references from relevant articles were searched for publications available before November 2011. Data collected after ART rollout were reviewed. RESULTS: Seven studies fulfilled the criteria for the analysis of acquired drug resistance while 22 fulfilled the criteria for the analysis of transmitted drug resistance (TDR). Acquired resistance was detected in 7·2% of patients on ART for 6-11 months, 11·1% at 12--23 months, 15·0% at 24-35 months, and 20·7% at (3)36 months. Multi-class drug resistance increased steadily with time on ART. The overall rate of TDR in all resource-limited countries studied was 6·6% (469/7063). Patients in countries in which ART had been available for (3)5 years were 1.7 times more likely to have transmitted drug-resistance than those living in a country where ART had been available for <5 years (p<0·001). The reported prevalence of transmitted HIVDR was 5·7% (233/4069) in Africa, 7·6% (160/2094) in Asia, and 8·4% (76/900) in Brazil. CONCLUSIONS: The emergence of drug resistance following access to antiretroviral therapy in RLSs resembles what was seen in resource-rich countries and highlights the need for virologic monitoring for drug failure, drug resistance testing, and alternative drug regimens that have proven beneficial in these resource-rich settings.

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