Positive Predictive Value of the WHO Clinical and Immunologic Criteria to Predict Viral Load Failure among Adults on First, or Second-Line Antiretroviral Therapy in Kenya

• Published in: PloS one Vol. 11; no. 7; p. e0158881
• Main Authors: Waruru, Anthony, Muttai, Hellen, Ng'ang'a, Lucy, Ackers, Marta, Kim, Andrea, Miruka, Fredrick, Erick, Opiyo, Okonji, Julie, Ayuaya, Tolbert, Schwarcz, Sandra
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 06.07.2016; Public Library of Science (PLoS)
• Subjects: Acquired immune deficiency syndrome; Adolescent; Adult; Adults; AIDS; Analysis; Anti-HIV Agents - therapeutic use; Antiretroviral agents; Antiretroviral drugs; Antiretroviral therapy; Biology and Life Sciences; Confidence intervals; Criteria; Developed countries; Disease control; Drug therapy; Failure; Female; Highly active antiretroviral therapy; HIV; HIV infections; HIV Infections - diagnosis; HIV Infections - drug therapy; HIV Infections - virology; Human immunodeficiency virus; Humans; Immunology; Kenya; Lentivirus; Male; Medical diagnosis; Medicine and Health Sciences; Middle Aged; Patients; People and Places; Physiologic monitoring; Predictive Value of Tests; Prognosis; Research and Analysis Methods; Retroviridae; Sensitivity and Specificity; Therapy; Treatment Failure; Viral load; Viral Load - drug effects; World Health Organization; Young Adult; Kenya; Atlanta Georgia; San Francisco California; United States > US
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0158881

Routine HIV viral load (VL) monitoring is the standard of care for persons receiving antiretroviral therapy (ART) in developed countries. Although the World Health Organization recommends annual VL monitoring of patients on ART, recognizing difficulties in conducting routine VL testing, the WHO continues to recommend targeted VL testing to confirm treatment failure for persons who meet selected immunologic and clinical criteria. Studies have measured positive predictive value (PPV), negative predictive value, sensitivity and specificity of these criteria among patients receiving first-line ART but not specifically among those on second-line or subsequent regimens. Between 2008 and 2011, adult ART patients in Nyanza, Kenya who met national clinical or immunologic criteria for treatment failure received targeted VL testing. We calculated PPV and 95% confidence intervals (CI) of these criteria to detect virologic treatment failure among patients receiving a) first-line ART, b) second/subsequent ART, and c) any regimen. Of 12,134 patient specimens tested, 2,874 (23.7%) were virologically confirmed as treatment failures. The PPV for 2,834 first-line ART patients who met either the clinical or immunologic criteria for treatment failure was 34.4% (95% CI 33.2-35.7), 33.1% (95% CI 24.7-42.3) for the 40 patients on second-line/subsequent regimens, and 33.4% (95% CI 33.1-35.6) for any ART. PPV, regardless of criteria, for first-line ART patients was lowest among patients over 44 years old and highest for patients aged 15 to 34 years. PPV of immunological and clinical criteria for correctly identifying treatment failure was similarly low for adult patients receiving either first-line or second-line/subsequent ART regimens. Our data confirm the inadequacy of clinical and immunologic criteria to correctly identify treatment failure and support the implementation of routine VL testing.