Factors associated with the incidence rate of HIV viral rebound among children and adults receiving antiretroviral therapy in Malawi using the Laboratory Management information System: 2011-2020

Objective: To describe the trends in the incidence rate of HIV VL rebound and assess the factors associated with the incidence rate of HIV VL rebound among the persons receiving ART in Malawi between 2011 and 2020. Methods: We analyzed routinely collected patient-level HIV VL data extracted from the Malawi Laboratory Management Information System (LIMS). We fitted a multivariable Cox regression model of having HIV VL rebound (>1000 copies/mL) using a forward step-wise selection method, with age and sex entered as a priori variables. We presented both crude and adjusted hazard ratios (aHR) of HIV VL rebound for the various independent variables. Statistical significance was set at P<0.05. Results: We evaluated 230,465 adults and children receiving ART and having at least one viral load test between 2011 and 2020. The median time between ART initiation and having a VL sample was 55 months (interquartile range: 25-92). The aHR for having HIV VL rebound were: 0.79 for females (95%CI:0.77-0.80, P<0.001) compared to males, 0.95 (95%CI: 0.94-0.98, P<0.001) for patients from rural compared to urban areas and 0.57 (95%CI:0.56-0.58, P<0.001) for routine compared to targeted VL tests. There was a decreasing trend in the aHR of patients having HIV VL rebound with increasing age. Conclusion: This is the first national analysis of Malawi HIV VL data from LIMS. Our findings show the need to take into account the geographic and demographic characteristics of the patients in order to persistently suppress HIV VL and consequently achieve 95% HIV VL suppression by 2030.