Longitudinal decline of plasma neurofilament light levels after antiretroviral initiation in people living with HIV

BackgroundThis retrospective follow-up study aims to investigate the dynamic longitudinal change of plasma neurofilament light (NfL) levels after antiretroviral therapy (ART) initiation in a cohort of people living with human immunodeficiency virus (HIV) (PWH). MethodsWe tested a convenience sample of 116 patients from the NORTHIV study. Plasma NfL levels-measured using Single molecule array (Simoa) technology-as well as other laboratory parameters were collected at baseline, weeks 4, 48, 96, and 144. Linear mixed-effects models were estimated to evaluate longitudinal change over time. Baseline CD4(+) T-cell levels, CDC classification, and HIV RNA levels were considered. Models were adjusted by age, sex, treatment regimen, and baseline serum creatinine levels. ResultsPlasma NfL levels were higher at baseline and also declined faster during the follow-up for participants with CD4(+) count 100 cells/mu l. No significant difference was found between the CD4(+) strata 100-199 and 200-499/mu l. Participants with CDC classification stages B and C had higher levels of plasma NfL at baseline, as well as faster decline compared with participants with stage A. No significant main effects or change over time was found in baseline HIV RNA levels, treatment regimen, or sex. ConclusionPlasma NfL is a sensitive biomarker to assess ongoing central nervous system injury in PWH. Plasma NfL concentrations decline relatively fast following ART initiation and then stabilize after 48 weeks. Plasma NfL concentrations are associated with CD4(+) count and stage of HIV disease. No correlations were seen with different ART regimens.