Introduction: HIV-infected patients, even if successfully treated, are at increased risk of neurocognitive impairment. Altered neuropsychological performance and neurocognitive impairment are frequently reported in patients with chronic HCV infection, often at stages characterized as having a lack of significant liver fibrosis and cirrhosis. A recent study suggests that FIB-4 index at cART initiation, and its modification over time are risk factors for major liver-related events and death, independently of infection with HCV.

Purpose of the study: We investigated the relationship between FIB-4 values and neurocognitive performance in HIV-infected patients without HCV and/or HBV coinfection.

Patients and Methods: We enrolled consecutive HIV-infected outpatients. In each patient demographic, clinical and therapeutic characteristics were recorded from clinical records. Each patient underwent a complete neurocognitive assessment with a battery of 8 tests: Trail Making Test-A (TMT-A), Trail Making Test-B (TMT-B), Digit Span (DSp), immediate (Rey 15) and delayed (D-Rey 15) recall of Rey’s 15, Digit Symbol (DSy), Letter fluency test (Flu), Rey complex figure (R-Fig). We also considered 2 global z-score NPZ-4 (TMA-Z+TMB-Z+DSp-Z+DSy-Z) and NPZ-8 (TMA-Z+TMB-Z+DSp-Z+DSy-Z+15-Z+15dif-Z+Flu-Z+FigR-Z). FIB-4 was also calculated considering values <1.45 were indicative of low level of hepatic fibrosis, values between 1.46 and 3.25 of moderate fibrosis and values >3.25 of advanced fibrosis. Patients with HCV and/or HBV hepatic coinfection were excluded.

Results: we enrolled 52 HIV-infected patients with a median age of 44 (IQR 38.5-50), 33 (63.4%) were males and 29 (55.7%) heterosexuals. Twelve (23%) had a previous AIDS diagnosis. Median CD4 cells count was 793 (IQR 616-1231.5) cells/mm³ and 46 (88.5%) had an undetectable HIV RNA. According to FIB-4 results, 48 (92.3%) patients had values <1.45 and 4 (7.7%) between 1.46 and 3.25 (26.2%), no patient had a value >3.25. Median FIB-4 value was 0.85 (IQR 0.70-1.06). FIB-4 levels were significantly correlated with longer duration of known HIV infection (Rho=0.29, p<0.05) and longer cART exposure (Rho=0.36, p<0.05) whereas no correlation was evidenced with level of education, previous AIDS diagnosis, CD4 cell nadir, current CD4 count, negative HIV RNA, NPZ-4 and NPZ-8 results.

Conclusions: Most HIV mono-infected patients had a fully suppressed HIV RNA and FIB-4 values consistent with low levels of hepatic fibrosis. Higher FIB-4 results were significantly correlated with longer HIV infection and cART duration but not with neurocognitive performance, suggesting a dissociation between long-term hepatic toxicity and neuroprotective function of antiretrovirals.