Change in Condom Use in Populations Newly Aware of HIV Diagnosis in the United States and Canada: A Systematic Review and Meta-Analysis.

HIV-infected individuals "aware" of their infection are more likely to use condoms, compared to HIV-infected "unaware" persons. To quantify this likelihood, we undertook a systematic review and meta-analysis of U.S. and Canadian studies. Twenty-one eligible studies included men who have sex with men (MSM; k = 15), persons who inject drugs (PWID; k = 2), and mixed populations of high-risk heterosexuals (HRH; k = 4). Risk ratios (RR) of "not always using condoms" with partners of any serostatus were lower among aware MSM (RR 0.44 [not significant]), PWID (RR 0.70) and HRH (RR 0.27); and, in aware MSM, with partners of HIV-uninfected or unknown status (RR 0.46). Aware individuals had lower "condomless sex likelihood" with HIV-uninfected or unknown status partners (MSM: RR 0.58; male PWID: RR 0.44; female PWID: RR 0.65; HRH: RR 0.35) and with partners of any serostatus (MSM only, RR 0.72). The association diminished over time. High risk of bias compromised evidence quality.