Different Trends of Distinct Time Points of AIDS Events Following HIV Diagnosis in Various At-risk Populations: A Retrospective Nationwide Cohort Study in Taiwan

INTRODUCTION: Acquired immune deficiency syndrome (AIDS) events at distinct time points after human immunodeficiency virus (HIV) diagnosis require various AIDS prevention strategies. However, no nationwide epidemiological surveillance studies have been conducted to explore the trends of distinct AIDS event time points in various at-risk populations. The aim of this study was to explore the issues and characterize the determinants of AIDS status after HIV diagnosis. METHODS: This nationwide cohort study enrolled HIV-positive Taiwanese during 1984–2016. AIDS events were classified into three time points (≤ 3, 4–12, > 12 months) by their occurrence time after HIV diagnosis. The periods of HIV/AIDS diagnosis were divided into six categories according to the calendar year of HIV/AIDS diagnosis: 1984–1991, 1992–1996, 1997–2001, 2002–2006, 2007–2011, and 2012–2016. HIV-positive Taiwanese during 1984–2011 were then selected to determine the factors associated with four AIDS statuses within 5 years after HIV diagnosis (no AIDS, AIDS ≤ 3 months, within 4–12 months, > 12 months) using multinomial logistic regression. RESULTS: Of 33,142 cases, we identified 15,254 (46%) AIDS events. The overall AIDS incidence (events/100 person-years) peaked during 1992–1996 (20.61), then declined, and finally stabilized from 2002 (8.96–9.82). The evolution of the proportion of distinct time points of AIDS events following HIV diagnosis changed significantly in heterosexuals and intravenous drug users (IDUs) during 1984–2016 (decline at ≤ 3 months in IDUs, decline at 4–12 months in IDUs, and increase at > 12 months in heterosexuals and IDUs) but not among men who have sex with men (MSM). Time points at ≤ 3 months remained at > 50% among MSM and at > 55% among heterosexuals. In multinomial logistic regression, IDUs (vs. men who have sex with men; MSM) had a lower risk of all AIDS statuses; heterosexuals (vs. MSM) had a higher risk of AIDS events ≤ 3 months after HIV diagnosis. CONCLUSION: The magnitude of AIDS in Taiwan has been stable since 2002. Enhancing early diagnosis among people with sexual contact and optimizing the HIV care continuum among heterosexuals and IDUs should be priorities for further AIDS prevention strategies.