Diagnostic Ability of Simple Noninvasive Blood Tests to Predict Increased Liver Stiffness in People Living with HIV and Steatotic Liver Disease.

BACKGROUND AND AIMS: Steatotic liver disease is common in people with human immunodeficiency virus (HIV)(PWH). Identifying those with advanced fibrosis (AF, bridging fibrosis or cirrhosis), F3-4, is important. We aimed to examine the performance of FIB-4 and nonalcoholic fatty liver disease (NAFLD) fibrosis score (NFS) in PWH to identify those with AF assessed by liver stiffness measurement (LSM).

METHODS: We prospectively collected data on adults participating in two NIH-sponsored HIV NAFLD networks. All had HIV on antiretroviral treatment (ART) ≥ 6 months with HIV RNA < 200 copies/mL. Those with viral hepatitis, other liver disease, excessive alcohol use or hepatic decompensation were excluded. Vibration controlled transient elastrography for LSM was performed, and AF defined as ≥11 kPa was compared to FIB-4 and NFS at predefined thresholds (<1.3 and >2.67 for FIB-4 and <-1.455 and > 0.675 for NFS).

RESULTS: 1065 participants were analyzed: mean age 51.6 yrs, 74% male, 28% White, 46% Black, 22% Hispanic, with 34% overweight (BMI 25-29 kg/m2) and 43% obese (BMI ≥ 30 kg/m2). Features of the metabolic syndrome were common: hyperlipidemia 35%, type 2 diabetes 17%, and hypertension 48%. The median CD4+ T-cell count was 666 cells/mm3, 74% had undetectable HIV RNA and duration of HIV-1 was 17 yrs with most taking a nucleoside reverse transcriptase inhibitor (92%) and an integrase inhibitor (83%). The mean LSM was 6.3 kPa and 6.3% had AF. The AUROC for FIB-4 and NFS to identify AF were 0.70 and 0.75, respectively. While both had high negative predictive values (NPV,97-98%), the sensitivity at low thresholds and specificity at high thresholds were 64% and 97% for FIB-4 and 80% and 96% for NFS. Neither FIB-4 nor NFS at either threshold had good positive predictive value to detect AF.

CONCLUSIONS: FIB-4 and NFS have excellent specificity and NPV for detecting AF and thus can be used as screening tools in PWH to exclude those with AF who do not need further testing (LSM) or referral to hepatologist.