Prevalence of autistic traits in people living with HIV and users of HIV pre-exposure prophylaxis: a cross-sectional study in Belgian HIV reference centres.

Autistic individuals are potentially at increased HIV risk due to gaps in adequate sexual health education, elevated sexual victimisation rates, and higher numbers of same-sex attraction compared to non-autistic adults. Data on autism prevalence among people living with HIV (PLHIV) or using Pre-Exposure Prophylaxis (PrEP) are lacking but critical to address gaps in sexual health provision for autistic individuals. This cross-sectional, multicentre study investigated the prevalence of autistic traits among PLHIV and PrEP users in Belgian HIV Reference Centres (HRCs). Adult PLHIV and PrEP users from four HRCs were invited to complete the validated Autism Spectrum Quotient (AQ) questionnaire and report prior autism diagnoses. Autism prevalence was estimated using the proportion scoring above the AQ cut-off of 32 (autism specificity .90, sensitivity .41). Among 1,439 participants (45.45% PLHIV, 53.79% PrEP users), 6.39% (95% CI 5.24% - 7.78%) surpassed the cut-off, with only 33.70% of them reporting prior autism diagnoses. A significant difference emerged: 4.28% of PLHIV versus 8.27% of PrEP users surpassed the threshold (p = 0.002). Rates of autistic traits in both groups were higher than in the general population, where only 2% exceed the 32 score. These findings highlight the importance of autism-friendly care in HIV clinics.