Brief Report: Prevention ResearchDoes Syphilis Increase the Risk of HIV-RNA Elevation >200 Copies/mL in HIV-Positive Patients Under Effective Antiretroviral Treatment? Data From the ICONA CohortGiacomelli, Andrea MDa; Cozzi-Lepri, Alessandro PhDb; Cingolani, Antonella MDc; Tavelli, Alessandro MScd; Mazzotta, Valentina MDe; Tesoro, Daniele MDf; Bassetti, Matteo MD, PhDg; Castagna, Antonella MDh; Di Biagio, Antonio MDg; Lichter, Miriam MD, PhDi; Monforte, Antonella d'Arminio MDf; Rusconi, Stefano MDa,j; on behalf of the ICONA Foundation Study GroupAuthor Information aIII Infectious Diseases Unit, ASST-FBF-Sacco, Department of Biomedical and Clinical Sciences DIBIC Luigi Sacco, Università di Milano, Milan, Italy; bCentre for Clinical Research, Epidemiology, Modelling and Evaluation (CREME), Institute for Global Health, UCL, London, United Kingdom; cInfectious Diseases Unit, Fondazione Policlinico Universitario A. Gemelli–Università Cattolica Del Sacro Cuore, Rome, Italy; dICONA Foundation, Milan, Italy; eHIV/AIDS Unit, INMI “Lazzaro Spallanzani” IRCCS, Rome, Italy; fClinic of Infectious and Tropical Diseases, ASST Santi Paolo e Carlo, University of Milan Department of Health Sciences, Milan, Italy; gInfectious Diseases Clinic, Policlinico San Martino Hospital, Department of Health Sciences, University of Genoa, Genova, Italy; hInfectious Diseases, IRCCS San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy; iInfectious Diseases Unit, Sapienza University of Rome, Santa Maria Goretti Hospital, Latina, Italy; and jCurrently, UOC Malattie Infettive, ASST Ovest Milanese, Ospedale di Legnano, Italy. Correspondence to: Andrea Giacomelli, MD, III Infectious Diseases Unit, ASST-FBF-Sacco, Department of Biomedical and Clinical Sciences DIBIC Luigi Sacco, Università di Milano, Via G.B. Grassi 74, Milano 20157, Italy (e-mail: [email protected]). The ICONA Foundation is supported by unrestricted grants from Gilead Sciences, ViiV Healthcare, MSD, Janssen, and Thera Technologies. No specific funding support has been received for the study design, data collection, analysis, and manuscript writing of this article. A preliminary report of the present research was presented as an oral communication at the 2020 Italian Conference on AIDS and Antiviral Research (OC 33), digital edition, October 14, 2020, Milan, Italy. The authors have no conflicts of interest to disclose. JAIDS Journal of Acquired Immune Deficiency Syndromes: October 1, 2021 - Volume 88 - Issue 2 - p 132-137 doi: 10.1097/QAI.0000000000002749 Buy Metrics Abstract Background: To assess the impact of syphilis infection on the risk of HIV-RNA elevation in people living with HIV (PLWH) with current HIV-RNA ≤50 copies/mL. Setting: The Italian Cohort Naive Antiretrovirals. Methods: All PLWH (2009–2020) under antiretroviral treatment with at least 2 consecutive HIV-RNA values ≤50 copies/mL before the date of syphilis diagnosis and at least 1 HIV-RNA determination after the syphilis event were enrolled. A control group of PLWH without syphilis was matched for mode of HIV transmission. Outcomes were defined using the first HIV-RNA measure in the time window ranging between −2 and +6 months of the diagnosis/index date. The primary outcome used a single value >200 copies/mL to define HIV-RNA elevation associated with risk of transmission. The association between syphilis infection and the protocol defined outcome was evaluated using logistic regression analysis. Results: Nine hundred twenty-six PLWH with a syphilis event were enrolled and matched with a random sample of 1370 PLWH without syphilis. Eighteen of the 926 (1.9%) with syphilis had ≥1 HIV-RNA >200 copies/mL in the window vs. 29/1370 (2.1%) of the not exposed (P = 0.77). In the multivariable analysis adjusted for age, year of diagnosis/index date, and clinical site, syphilis infection was not associated with the risk of HIV-RNA >200 copies/mL (adjusted odds ratio 0.81; 95% confidence interval 0.43–1.52, P = 0.508). Conclusions: We did not find any evidence for an association between syphilis infection and viral elevation >200 copies/mL. Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.