Cohort profile: the Viral load Cohort North-East Lesotho (VICONEL) from 2016 to 2022 – cohort description, test volumes, predictors of viraemia, and the road ahead

Abstract

AbstractPurposeThe prospective Viral load Cohort North-East Lesotho (VICONEL) aims to support clinical management and generate scientific evidence to inform HIV care. Specifically, VICONEL allows for monitoring of HIV treatment outcomes and health system performance, encompasses a biobank for further research with routinely collected blood plasma samples of consenting participants, and provides a valuable framework for nested observational and interventional studies.ParticipantsVICONEL captures routine viral load test results alongside associated demographic and treatment information among people in care for HIV in Lesotho, southern Africa. As of December 2022, it encompasses all viral load testing from 23 healthcare facilities in two districts of Lesotho.Findings to dateFrom January 2016 to December 2022, 114’838 viral load test results were available for 27,472 participants. At the time of the last viral load test, median age was 42 years (interquartile range [IQR]: 33-53); 17,324 (63%) were adult women, 9,273 (34%) adult men, and 870 (3%) children <15 years (age/sex missing for 5); and median time taking antiretroviral therapy (ART) was 6.0 years (IQR 3.0-9.2). Overall, the proportion of cohort participants with viral suppression to <1,000 copies/mL has continually exceeded 90% and has been above 95% since 2020; however, this proportion has consistently been lower among children. Sex, age category / ART regimen core agent (combined variable), time since ART initiation, and district were independently associated with viraemia.Future plansVICONEL offers potential for i) further digitalisation and automation of results sharing at the client, facility, and district/national level, ii) integration of additional clinical and diagnostic data, including HIV comorbidities, and iii) embedding randomised trials.Strengths and limitations-VICONEL covers all HIV viral load testing from 23 clinics in two districts in Lesotho and is thus highly representative.-Data capture occurs at the time point of viral load testing; thus, treatment or clinical data are not updated between viral load tests, and reasons for exiting the cohort are not followed up.-Participant data beyond viral load results are limited to key demographic, clinical, and treatment information.-The cohort and associated biobank have proven to be a valuable platform for nested observational and interventional research, including randomised trials.-Core functions can be maintained at low cost, constituting a model for near-real-time monitoring of treatment outcomes with limited resources.