{ "abstract": "Background In daily practice, an increasing number of individuals aged ≥50 years are requesting HIV pre-exposure prophylaxis (PrEP); however, real-world data on this population remain limited and often underreported.Methods We conducted a cross-sectional analysis using baseline data from the PRIDE cohort (enrolled in 2025). Participants were stratified into three age groups:<50, 50–65, and >65 years ( table 1). We described and compared demographics, anthropometrics, sexual behaviour, PrEP regimen and dosing strategy, and history of sexually transmitted infections (STIs) across the three age categories. χ2/Fisher’s exact and Kruskal–Wallis test were used as appropriate.Results Overall, 5,604 PrEP users were included; 4,685 (83.6%) were aged <50 years, 862 (15.4%) were 50–65 years, and 57 (1.0%) were >65 years. Most participants were male at birth (98.5%). Compared with those <50, older participants had a higher body mass index (median BMI 23.44 kg/m 2 in <50 vs 24.66 in 50–65 and 24.49 in >65; p=0.001). Reporting partners of both sexes was more common in the older groups (8.1% in <50 vs 11.0% in 50–65 and 22.8% in >65; p=0.001). Italian nationality was highly prevalent across all age groups and reached 98.3% among those >65. At enrolment, PrEP was mainly based on tenofovir disoproxil fumarate/emtricitabine in all age groups. Long-acting cabotegravir was used more often with increasing age (9.8% in <50, 11.5% in 50–65, 18.8% in >65). On-demand PrEP was widely used and was particularly frequent among participants aged >65 years (48.8% in <50 vs 67.6% in >65). A previous history of STIs was very common and overall similar across ages (68.8% in <50, 70.4% in 50–65, 61.5% in >65; p=0.343), but the distribution of specific infections differed across age groups: syphilis was reported more often in older participants (24.1% in those aged <50 years vs 36.5% in 50-65 years and 28.9% in >65 years; p=0.001), whereas rectal gonorrhoea decreased with age (17.8% vs 11.7% and 3.9%; p=0.001). A history of hepatitis A increased markedly with age (2.3% in <50 years vs 5.8% in 50-65 years and 15.4% in >65 years; p=0.001), and hepatitis B was also more frequent in older groups, particularly among participants aged 50-65 years (1.1% in <50 years vs 6.6% in 50-65 years and 3.9% in >65 years; p=0.001) (figure 1).Conclusions In the PRIDE cohort, people aged ≥50 years account for a non-negligible proportion of PrEP users and display distinct clinical and behavioural characteristics compared with younger participants. Differences in PrEP strategy (greater use of long-acting and on-demand regimens) and in the distribution of STIs suggest that prevention approaches should be adapted for older adults rather than extrapolated from younger. Tailored counselling and targeted screening strategies may improve prevention outcomes and counter the misconception that older adults are a lower-priority population for HIV prevention.Abstract OC23 Table 1Demographic and clinical characteristies of Prep users grouped by the age at enrollmentAbstract OC23 Figure 1Himery of STls by age at enrellment (denaminater are Prep oie wha deelared presence or absace ef STis in medical history)", "authors": [ { "affiliations": [ "Link Campus University, Rome, Italy", "Università degli Studi della Campania Luigi Vanvitelli, Naples, Italy" ], "name": "A Russo" }, { "affiliations": [ "Infectious Diseases Unit, IRCCS San Raffaele Scientific Institute, Milan, Italy" ], "name": "R Lolatto" }, { "affiliations": [ "National Institute for Infectious Diseases Lazzaro Spallanzani IRCCS, Rome, Italy" ], "name": "A Giacinta" }, { "affiliations": [ "Infectious Diseases Unit, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan, Italy" ], "name": "G Bozzi" }, { "affiliations": [ "Milano Checkpoint ETS, Milan, Italy" ], "name": "E Caruso" }, { "affiliations": [ "Infectious Diseases Unit, Vita-Salute San Raffaele University, Milan, Italy" ], "name": "AR Raccagni" }, { "affiliations": [ "UOC Malattie infettive, PO Umberto I ASP Siracusa, Siracusa, Italy" ], "name": "RF Del Vecchio" }, { "affiliations": [ "Department of Infectious Diseases, ASST Fatebenefratelli Sacco University Hospital, Milan, Italy" ], "name": "C Fusetti" }, { "affiliations": [ "PO Cotugno, AORN dei Colli, Naples, Italy" ], "name": "A Guida" }, { "affiliations": [ "Azienda Sanitaria Locale Città di Torino, Turin, Italy" ], "name": "AM Lucchini" }, { "affiliations": [ "S.C. Malattie Infettive, IRCCS San Gerardo dei Tintori, Monza, Italy" ], "name": "A Renzani" }, { "affiliations": [ "Clinic of Infectious Diseases, Department of Health Sciences, ASST Santi Paolo e Carlo, University of Milan, Italy" ], "name": "G Ancona" }, { "affiliations": [ "BLQ Checkpoint, Bologna, Italy" ], "name": "S Cerere" }, { "affiliations": [ "Infectious Disease Unit, Sant’Andrea Hospital, Sapienza University of Rome, Rome, Italy" ], "name": "P Vassalini" }, { "affiliations": [ "Checkpoint Plus Roma, Rome, Italy" ], "name": "VL del Negro" }, { "affiliations": [ "Infectious and Tropical Diseases Unit, Padua University Hospital, Padua, Italy Project and Clinical Research Unit, Padua University Hospital, Padua, Italy" ], "name": "A Cattelan" }, { "affiliations": [ "A.S.A. Onlus - Association of Solidarity AIDS, Milan, Italy" ], "name": "M Cernuschi" }, { "affiliations": [ "Clinical and Research Infectious Diseases Department, National Institute for Infectious Diseases Lazzaro Spallanzani, IRCCS, Rome, Italy" ], "name": "V Mazzotta" }, { "affiliations": [ "Infectious Diseases Unit, Vita-Salute San Raffaele University, Milan, Italy", "Infectious Diseases Unit, IRCCS San Raffaele Scientific Institute, Milan, Italy" ], "name": "S Nozza" } ], "title": "OC23 PrEP beyond 50: baseline profile and PrEP strategies of older users in the Italian PRIDE cohort", "uid": "9eb227b8-5a51-57d6-8d97-4ea3599724c7" }