Predicament and Antiretroviral Drug Resistance among People Living with HIV in the Upper Southern Region of Thailand

Abstract

Thailand's national antiretroviral drug access program promotes increased access to antiretroviral drugs for people living with HIV, while potentially increasing drug resistance. This retrospective descriptive study aimed to assess the HIV infection situation in HIV-infected individuals receiving antiretroviral therapy, the prevalence of drug resistance, mutation patterns, and factors associated with drug resistance in the upper southern region of Thailand. The data used in this research were obtained from the results of the HIV viral load test at the medical laboratory for disease control, the Office of Disease Prevention and Control Region 11, Nakhon Si Thammarat, from October 1, 2020 to September 30, 2024. Data analysis was performed as follows: 1) general data of the study sample were analyzed using proportions, 2) HIV-1 genotype mutation patterns were analyzed using Next Generation Sequencing technology, and 3) factors associated with drug resistance were analyzed using Chi-square statistics. The study results revealed that out of a total of 41,002 samples studied, 55.4% were male and 44.6% were female, with an average age of 38.7 years. The majority of infected persons (94.1%) had an HIV viral load of less than 200 copies/mL, while a minority (4.0%) had a load greater than 1,000 copies/mL. The prevalence of drug resistance was 1.8%. The most common antiretroviral resistance was NNRTIs (46.0%), followed by NRTIs and NNRTIs in combination at 40.0%. The K103N/S and V106I/M positions were the most commonly mutated in NNRTIs, indicating high levels of resistance to nevirapine (NVP) and efavirenz (EFV). The analysis results of factors associated with antiretroviral drug resistance in the upper southern region of Thailand indicated that all studied factors had a statistically significant relationship with drug resistance through the mechanism of inhibition of the reverse transcriptase enzyme. These research findings suggest appropriate antiretroviral therapy selection. Meanwhile, the group of infected individuals with virologic failure and those with HIV viral loads greater than 1,000 copies/mL but no mutations are the groups for which the focus should be on reducing viral loads to the lowest possible level.