Trends of antiretroviral drug resistance in treatment-naive patients with human immunodeficiency virus type 1 infection in Taiwan.
OBJECTIVE
To determine the prevalence and trends of antiretroviral drug resistance among HIV-1-infected Taiwanese patients who have been provided with free-of-charge antiretroviral therapy (ART) since 1990.


METHODS
Blood samples collected from 786 HIV-1-infected patients from 1999 to 2006 were subjected to genotypic resistance assay. Antiretroviral resistance mutations were identified in accordance with the antiretroviral resistance mutation list of the International AIDS Society-USA Consensus Guidelines. Trends of resistance were studied in patients enrolled in two periods: before (period 1, January 1999 to December 2003) and after (period 2, January 2004 to December 2006) the CRF07_BC outbreak among injection drug users (IDUs).


RESULTS
The frequency of HIV-1 isolates harbouring one or more primary mutations associated with antiretroviral resistance to reverse transcriptase inhibitors or protease inhibitors increased significantly from 6.6% in period 1 to 12.7% in period 2 (P = 0.003). A significant increase in prevalence of antiretroviral drug resistance was observed among men who have sex with men and patients infected with HIV subtype B. In multivariate analysis, hepatitis C virus (HCV) exposure, which exhibited collinearity with injection drug use and infection with CRF07_BC, represented a lower risk for infection with resistant viruses.


CONCLUSIONS
Our findings suggest that the prevalence of antiretroviral resistance has increased in Taiwan over the past 8 years after the introduction of combination ART. IDUs who were HCV-seropositive and infected with CRF07_BC were at lower risk for infection with antiretroviral-resistant viruses.
Chang
Sui-Yuan
SY
Department of Clinical Laboratory Sciences and Medical Biotechnology, National Taiwan University College of Medicine, Taipei, Taiwan.
Chen
Mao-Yuan
MY
Lee
Chun-Nan
CN
Sun
Hsin-Yun
HY
Ko
Wilson
W
Chang
Shu-Fang
SF
Chang
Kei-Lung
KL
Hsieh
Szu-Min
SM
Sheng
Wang-Huei
WH
Liu
Wen-Chun
WC
Wu
Cheng-Hsin
CH
Kao
Chuan-Liang
CL
Hung
Chien-Ching
CC
Chang
Shan-Chwen
SC
D000328:Adult; D044966:Anti-Retroviral Agents / Q000494:pharmacology / Q000627:therapeutic use*; D024882:Drug Resistance, Viral / Q000187:drug effects / Q000235:genetics*; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000453:epidemiology / Q000235:genetics; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics; D006801:Humans; D008297:Male; D013624:Taiwan / Q000453:epidemiology
D044966:Anti-Retroviral Agents