People
living with HIV are about twice as likely to develop steatosis, or fat
accumulation in the liver, even if they don't have hepatitis B or C
co-infection, according to a study presented
at the recent 22nd International AIDS
Conference (AIDS 2018) in Amsterdam.
Liver
disease is a major cause of morbidity and mortality among people living with
HIV. Hepatitis B or C virus (HBV or HCV), heavy alcohol consumption, certain
antiretroviral medications and other causes of liver injury can lead to the
development of liver fibrosis, cirrhosis and steatosis. But these can also occur
without such liver-specific risk factors. Previous studies have seen steatosis rates
among people with HIV ranging from around 35% to 75%.
Fatty
liver disease, associated with metabolic syndrome, is a growing problem as the
population becomes more obese. Over time, non-alcoholic fatty liver disease
(NAFLD) and its more advanced stage, non-alcoholic steatohepatitis (NASH), can
lead to liver function impairment, liver cancer and the need for a liver
transplant.
Glossary
- FibroScan
A non-invasive test, used instead of a biopsy, to measure the stiffness
or elasticity of the liver using an ultrasound probe.
- steatosis
Abnormal fat deposits in the liver.
Hugo Perazzo of Fundação Oswaldo Cruz in Rio
de Janeiro and colleagues evaluated the prevalence of and risk factors
associated with liver steatosis in people with HIV mono-infection – that is, those
without HBV or HCV co-infection – compared with HIV-negative individuals.
The study
drew from 649 people with HIV followed at the National
Institute of Infectology (INI/Fiocruz)
and 15,105 HIV-negative people in
the Brazilian Longitudinal Study of Adult Health
(ELSA-Brasil) cohort.
In the HIV-positive
group 58% were men, 23% were black or 'Pardo'
(mixed race) and the median age was 44 years. The median body mass index (BMI) was
24.4 (25 and above is considered overweight) and a third had metabolic syndrome,
a cluster of cardiovascular risk factors including abdominal obesity, hypertension
(high blood pressure), high blood glucose and abnormal lipid levels.
A total
of 333 HIV-positive participants were paired with
an equal number of HIV-negative people. Although they were approximately
matched based on demographic characteristics and metabolic factors, there were
some significant differences. The HIV-positive group was younger, had fewer women, were less likely to
be black/Pardo and were more likely to have diabetes, while the HIV-negative
group had higher average BMI and were more likely to have abnormal lipids,
hypertension and metabolic syndrome.
For each participant, the researchers calculated a Fatty Liver Index
(FLI) score based on laboratory and physical exam findings including triglyceride and gamma-glutamyl-transferase (GGT)
liver enzyme levels, BMI and waist
circumference. Liver steatosis was defined as an FLI of 60 or higher.
More than a third of the participants with HIV
(35%) were found to have steatosis. HIV infection was an independent risk factor, doubling
the likelihood of having fatty liver, Perazzo reported.
HIV-positive people with steatosis were, on average, older, had higher
BMI and waist circumference, had a higher CD4 count and had been on antiretroviral therapy (ART) longer
than those without. There were no significant differences related to nadir
(lowest-ever) CD4 count, current ART regimen or current viral suppression.
About two-thirds (68%) of the HIV-positive people with steatosis had metabolic syndrome, 46%
had abnormal lipids, 46% had hypertension, 41% had diabetes and 54% were
described as having 'poor clinical management'.
In a multivariate analysis, independent risk factors for fatty liver
were HIV infection (odds ratio 2.1), male sex (OR 5.36), being black/Pardo (OR
0.22), higher BMI (OR 1.91), diabetes (OR 5.79), abnormal lipids (OR 2.57) and hypertension
(OR 2.56). In addition, higher CD4 count (OR 1.13 per 100 cell/mm3),
higher cumulative HIV viral load (OR 1.25 per 10 log copies/ml per year) and
poor clinical management (OR 0.36) also increased the risk of steatosis.
"HIV-infected individuals had two-fold higher odds for presence of
steatosis compared to uninfected paired controls," the researchers
concluded. "Traditional and HIV-specific risk factors were independently associated with liver steatosis
in people living with HIV."
They recommended that management of metabolic risk factors should be
integrated into HIV care to decrease the burden of liver diseases in this
population.
In response to a question, Perazzo said that FibroScan, an imaging method for assessing fibrosis and steatosis,
was not available at the time of the study. Session moderator Marina
Klein of McGill University in Montreal noted that
researchers are looking for more accurate non-invasive biomarkers of fatty
liver as it becomes a more prevalent cause of serious liver disease in people with and without HIV.