Clinical predictor score to identify patients at risk of poor viral load suppression at six months on antiretroviral therapy: results from a prospective cohort study in Johannesburg, South Africa

• Published in: Clinical epidemiology 2019-05, Vol.11, p.359-373
• Main Authors: Mbengue, Mouhamed Abdou Salam, Chasela, Charles, Onoya, Dorina, Mboup, Souleymane, Fox, Matthew P, Evans, Denise
• Format: Article
• Language: English
• Subjects: AIDS treatment; algorithm; Algorithms; Antiretroviral agents; Antiretroviral therapy; Drug therapy; Efavirenz; Health counseling; HIV; HIV patients; monitoring; Original Research; Patient compliance; resource limited; risk score; viral load
• ISSN: 1179-1349; 1179-1349
• DOI: 10.2147/CLEP.S197741

As countries work toward 90:90:90 targets, early identification of patients with inadequate response to antiretroviral therapy (ART) is critical for achieving optimal HIV treatment outcomes. We developed and evaluated a clinical prediction score (CPS) to identify HIV-positive patients at risk of poor viral load suppression at 6 months on ART. We conducted a prospective cohort study of HIV-positive ART naïve adults (≥18 years) initiating standard first-line ART between February 2012 and April 2014 at Themba Lethu Clinic in Johannesburg, South Africa. We used Modified Poisson regression to estimate the association between patient characteristics and poor viral load suppression, defined as a viral load ≥400 copies/mL at 6 months on ART. We developed a CPS following the Spiegel Halter and Knill-Jones approach and determined the diagnostic accuracy compared to viral load as the "gold standard". We identified the optimal cutoff at which the CPS would identify those at risk of poor viral load suppression. Among 353 patients, 67.7% had a viral load measurement at 6 months on ART and 30.1% of these were viremic (≥400 copies/mL). Male gender, platelet count