Factors Associated with Willingness to Participate in HIV Vaccine Trials Among HIV-Negative Injection Drug Users and Young Gay and Bisexual Men

Abstract

We identified factors associated with willingness to participate in HIV vaccine trials among HIV-negative injection drug users (IDU) and young men having sex with men (MSM) enrolled in prospective cohort studies in Vancouver. Of 435 IDU and 330 MSM, 83% and 63% were willing to participate in HIV vaccine trials, respectively. In both samples, greater willingness was associated with high perceived HIV threat, and with initiating injection or first having sex with men at younger ages. Among IDU, frequent needle exchange programs attenders were more willing to participate than infrequent attenders (p = .004). Among MSM, those with a higher depression score were more willing to participate (p < .001). In logistic regression models, independent predictors of willingness to participate included frequent needle exchange attendance among IDU, and high depression score and high perceived HIV threat among MSM. This suggests that needle exchange programs are ideal venues for recruiting high-risk IDU into HIV vaccine trials. Since MSM reporting more depressive symptoms were more willing to participate, HIV vaccine trials should provide appropriate counseling to safeguard participants' psychological and physical health.