Time From Human Immunodeficiency Virus Seroconversion to Reaching CD4+ Cell Count Thresholds <200, <350, and <500 Cells/mm3: Assessment of Need Following Changes in Treatment Guidelines

• Published in: Clinical infectious diseases Vol. 53; no. 8; pp. 817 - 825
• Main Authors: Lodi, Sara, Phillips, Andrew, Touloumi, Giota, Geskus, Ronald, Meyer, Laurence, Thiébaut, Rodolphe, Pantazis, Nikos, del Amo, Julia, Johnson, Anne M., Babiker, Abdel, Porter, Kholoud
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 15.10.2011
• Subjects: Adult; AIDS; Antiretrovirals; Biological and medical sciences; Carts; CD4 Lymphocyte Count; Cohort Studies; Confidence interval; Drug Administration Schedule; Drug Therapy, Combination; Early Diagnosis; Europe - epidemiology; Female; Follow-Up Studies; HIV; HIV infections; HIV Infections - drug therapy; HIV Infections - epidemiology; HIV Infections - immunology; HIV Infections - virology; HIV seropositivity; HIV Seropositivity - drug therapy; HIV Seropositivity - immunology; HIV-1 - immunology; HIV/AIDS; Human viral diseases; Humans; Immunodeficiencies; Immunodeficiencies. Immunoglobulinopathies; Immunopathology; Infectious diseases; Interval estimators; Linear Models; Male; Medical sciences; Men; Middle Aged; Mortality; Practice Guidelines as Topic; Risk Factors; Sexual Behavior; Time Factors; United States - epidemiology; Viral diseases; Viral diseases of the lymphoid tissue and the blood. Aids; United States; Europe; Infection; Virus; Numeration; Immunopathology; Treatment; Viral disease; Retroviridae; AIDS; Human immunodeficiency virus; Immune deficiency; Lentivirus; Recommendation
• DOI: 10.1093/cid/cir494
• ISSN: 1058-4838; 1537-6591

Background. Recent updates of human immunodeficiency virus (HIV) treatment guidelines have raised the CD4+ cell count thresholds for antiretroviral therapy initiation from 350 to 500 cells/mm 3 in the United States and from 200 to 350 cells/mm 3 in mid- and low-income countries. Robust data of time from HIV seroconversion to CD4+ cell counts of 200, 350, and 500 cells/mm 3 are lacking but are needed to inform health care planners of the likely impact and cost effectiveness of these and possible future changes in CD4+ cell count initiation threshold. Methods. Using Concerted Action on Seroconversion to AIDS and Death in Europe data from individuals with well-estimated dates of HIV seroconversion, we fitted mixed models on the square root of CD4+ cell counts measured before combined antiretroviral therapy (cART) initiation. Restricting analyses to adults (age >16 years), we predicted time between seroconversion and CD4+ cell count <200, <350, and <500 cells/mm 3 as well as CD4+ cell count distribution and proportions reaching these thresholds at 1, 2, and 5 years after seroconversion. Results. Median (interquartile range [IQR]) follow-up for the 18 495 eligible individuals from seroconversion while cART-free was 3.7 years (1.5, 7). Most of the subjects were male (78%), had a median age at seroconversion of 30 years (IQR, 25—37 years), and were infected through sex between men (55%). Estimated median times (95% confidence interval [CI]) from seroconversion to CD4+ cell count <500, <350, and <200 cells/mm 3 were 1.19 (95% CI, 1.12—1.26), 4.19 (95% CI, 4.09—4.28), and 7.93 (95% CI, 7.76—8.09) years, respectively. Almost half of infected individuals would require treatment within 1 year of seroconversion for guidelines recommending its initiation at 500 cells/mm 3 , compared with 26% and 9% for guidelines recommending initiation at 350 and 200 cells/mm 3 , respectively. Conclusions. These data suggest substantial increases in the number of individuals who require treatment and call for early HIV testing.