Factors associated with viral load non-suppression in people living with HIV on ART in Nigeria: cross-sectional analysis from 2017 to 2021

Objectives Identify factors (demographic and clinical) associated with a non-suppressed viral load (VL) of people living with HIV (PLHIV) on antiretroviral therapy (ART) in Nigeria.Design Cross-sectional study.Setting Sixteen US Agency for International Development supported states in Nigeria.Participants 585 632 PLHIV on ART.Primary outcome measures VL non-suppression (defined as having a VL of at least 1000 HIV RNA copies per mL of plasma). χ2 testing and multivariable modified Poisson regression with robust variance estimates were conducted on routinely collected ART programme data.Results Sixty-six per cent of the study population were females. The largest age groups were 25–34 and 35–44, accounting for 32.1% and 31.1%, respectively. Males had a 9% greater likelihood (adjusted prevalence ratio, APR=1.09) of being non-suppressed. The age groups below 60+ (APR=0.67) had a higher likelihood of a non-suppressed VL, with the highest in the 0–14 age group (APR=2.38). Clients enrolled at tertiary and secondary level facilities had the greatest likelihood of a non-suppressed VL. Clients who started ART between 2010 and 2015 had the greatest likelihood of viral non-suppression (APR=6.19). A shorter time on ART (