BACKGROUND: Research suggests treatment adherence is an important means of preventing HIV transmission, however; drug resistance can inhibit the effectiveness of certain treatment options. Genetic sequence testing is an essential tool for assessing an individual’s drug resistance and developing an effective treatment plan. This analysis reviews the influence of drug resistance on those in stage 3 at HIV diagnosis in the District of Columbia.
METHODS: People over the age of 12, diagnosed with HIV and reported to the DC HIV Surveillance system between 2010 and 2014 with a report of genetic testing and no evidence of previous ARV use were included in this analysis. Stage at diagnosis was assigned by applying the CDC guidelines to the first CD4 test result assessed after diagnosis. The first reported genetic sequence was translated into its corresponding drug resistances using the HIV Drug Resistance Database from Stanford University. Resistance was defined as having any evidence of resistance to any drug included in the database and was separated into protease inhibitors and reverse transcriptase inhibitors. Chi-squared analyses were used to assess the relative risk of drug resistance.
RESULTS: Through 2015, 959 HIV diagnoses met the inclusion criteria. Evidence of drug resistance was found in 217 cases (22.63%) Thirty-nine of those cases exhibited resistance to protease inhibitors (4.07%) and 178 cases had evidence of resistance to reverse transcriptase inhibitors. (18.56%) For those in stage 3 at diagnosis, the relative risk of any drug resistance increased by 49.2% compared with all other stages. (95%CI: 1.16-1.91, p=0.002). This risk increased when resistance to reverse transcriptase inhibitors was isolated. (RR 1.53, 95%CI: 1.18-1.99, p=.002) The relative risk of resistance among those in stage 3 at diagnosis was then isolated to seven particular drugs. The highest relative risk of resistance was found in the drugs Lamivudine and Emtricitabine with an increased risk of 182.26% among those in stage 3 compared with all other stages. (95% CI: 2.065-3.858, p=<0.0001)
CONCLUSIONS: The results of this analysis suggest that people in stage 3 at diagnosis have an increased risk of drug resistance when compared to people diagnosed in any other stage. It is important to note that this analysis utilized HIV surveillance data which is limited to only labs and case reports received by the health department. Future research should be conducted to better understand the interaction of drug resistance and stage at diagnosis as well as possible drivers of drug resistance.