For most patients with nonalcoholic fatty liver disease (NAFLD) who die, the cause of death is heart disease. Although NAFLD is connected to metabolic disease like diabetes, obesity, arterial hypertension, and atherogenic dyslipidemia, a new study from the Pierre and Marie University shows that NAFLD is an independent risk factor for cardiovascular diseases like atherosclerosis.
NAFLD is characterized by inflammation of the liver and accumulation of fatty deposits. These deposits express pro-inflammatory cytokines, procoagulant factors, and genes that contribute to an accelerated progression of atherogenesis.
"This raises the possibility that the link between NAFLD and cardiovascular mortality might not simply be mediated by shared, underlying, common risk factors, but rather that NAFLD independently contributes to increasing this risk," said senior author of the Journal of Hepatology
publication Vlad Ratziu, MD, PhD.
In a study of almost six thousand people conducted between 1995 and 2012, researchers looked data from carotid ultrasounds to understand the connection between NAFLD and atherosclerosis. They measured carotid intima-media thickness as well as carotid plaques and compared the data to the Fatty Liver Index (FLI). The carotid arteries vitally supply blood the brain, neck, and face.
Fatty liver, also called steatosis, is associated with another measurement called carotid intima-media thickness (C-IMT), which the FLI takes into consideration. As a preatherosclerotic lesion, C-IMT is a factor that can predict cardiovascular events.
The researchers saw a direct relationship between C-IMT and fatty liver: if one increased so did the other. However, the saw that C-IMT increase acts independently of any “traditional” cardiometabolic risk factors present.
Researchers followed up with almost two thousand of the patients who participated in the earlier years of the study to look at how their carotid plaques and fatty liver had developed over time. After eight years, 12 percent of the patients showed steatosis and a C-IMT increase, and 23 percent had carotid plaques. However, C-IMT did not change in the follow-up participants who stayed free of steatosis.
Ultimately, the scientists concluded that NAFLD is a precursor of metabolic syndrome, and diagnosing steatosis is extremely important to be proactive in preventing and treating cardiovascular disease.
Source: Elsevier Health Sciences