The Link Between Unsafe Sex, Poor HAART Adherence, Resistance and Drug Resistant HIV Transmission

Is high-risk sexual behavior among HIV-infected patients on highly-active antiretroviral therapy (HAART) associated with poor antiretroviral adherence and the subsequent development of antiretroviral-resistant virus?

That is what Napravnik et al set out to discover at the University of North Carolina (UNC) Center for AIDS Research (CFAR). Patients were asked to complete an interview about sexual habits, antiretroviral utilization and demographics. For the purposes of this study, unprotected sex was defined as having 1 or more sex partners in the last year where either the patient or their partner was not using a condom. Poor antiretroviral adherence was defined as having missed a dose in the prior 3 days. Antiretroviral mutations were defined using the IAS-USA mutation definitions.¹

The researchers enrolled 303 patients. Seventy-three percent (221/303) of the patients indicated they had had sexual activity in the last year; 60% with 1 partner, 15% with 2 different partners, 8% with 3 partners, and 17% with 4 or more partners. Fourty percent (120/303) indicated they had had unprotected sexual activity in the last year.

Analysis indicated that unprotected sexual activity was more common among:

• those who were younger than 45 years old,

• men who had sex with men, or

• had active substance abuse,

• those who were antiretroviral naive, or

• those who were not currently taking antiretrovirals, and

• those who had more years of antiretroviral exposure.

Factors that were found not to be associated with unprotected sex included:

• alcohol use,

• a diagnosis of AIDS,

• years since HIV diagnosis,

• number of antiretroviral regimens,

• HIV viral load level, or

• the presence of antiretroviral resistance.

Twenty-eight percent of the patients in the study reported less than optimal antiretroviral adherence. Of these patients, 66% reported having unprotected sex compared to 46% with perfect adherence.

Thirty-nine percent of patients (45/114) with available genotypes reported unprotected sex. Within this group, 89% (40/45) had 1 or more primary drug mutations (median 4), 42% with 1 or more PI mutations, 33% with 1 or more NNRTI mutations, and 73% with 1 or more NRTI mutations. Sixty-nine percent had mutations to 2 or more antiretroviral classes and 27% had mutations to 3 classes of antiretrovirals.

The conclusions from this study are that unprotected sex is common in the southeastern United States in patients who attend this clinic. However, the study is important because it is likely that the behavior found in this clinic is going on in other clinics as well. The authors also conclude that unsafe sex practices are indeed related to less than perfect adherence to antiretrovirals, which in turn is related to a greater likelihood of having an antiretroviral-resistant strain of HIV and the further likelihood of transmitting that drug-resistant strain to other people.

Although the sample population was sufficient and considered both men and women regarding unsafe sex practices, the number of those patients with resistance test results and who engaged in unsafe sex practices was relatively small. Thus, these findings may not be directly transferable to other populations.

Although sometimes a sensitive issue, practitioners should become comfortable in asking about unsafe sex practices and addressing this issue in order to reduce HIV transmission in general and antiretroviral-resistant HIV infection in particular. Although the likelihood of transmitting antiretroviral-resistant virus depends on a number of issues, including both host and viral factors, the kind of self-reported behavior seen in this study is an important marker for the continued epidemic and spread of HIV infection in the United States.

Footnote

1. Johnson VA, Brun-Vézinet F, Clotet B, et al. Update of the drug resistance mutations in HIV-1: 2005. Topics in HIV Medicine. March/April 2005;13(1):51,56-57.