New research shows that mild fatty liver disease is linked to higher mortality rates. Previous studies found that patients who had non-alcoholic fatty liver disease (NAFLD) and advanced fibrosis or cirrhosis had an increased risk of death. This new research shows how even mild fatty liver disease can increase that risk.
Non-alcoholic fatty liver disease, NAFLD, affects nearly one in four adults in Europe and the U.S., so it’s important to understand just how much risk of mortality is involved with the level of severity of the disease. NAFLD represents the most common cause of chronic liver disease in Western countries and is often caused by obesity.
Small clinical studies had previously demonstrated that advanced liver fibrosis is the most important predictor of mortality in patients with NAFLD. However, this new study can fill the gaps in research by offering population-level data that had previously been missing from cohorts with liver histology.
For the study, researchers at Karolinska Institutet in Sweden and Massachusetts General Hospital matched 10,568 individuals with biopsy-confirmed NAFLD to general population controls. All matches were made through Sweden’s comprehensive, nationwide registers. It was found that all NAFLD stages were associated with excess mortality risk, even early stages of the disease.
With all stages, the risk was primarily driven by deaths from extra-hepatic cancer and cirrhosis, while the risks of cardiovascular mortality or hepatocellular carcinoma (HCC) mortality were relatively modest.
The study concluded that patients with NAFLD had a 93 percent increased risk of mortality, but the numbers varied with disease severity. The risk increased progressively from the mildest form of NAFLD (simple steatosis), non-fibrotic steatohepatitis (NASH), non-cirrhotic fibrosis to severe NAFLD with liver cirrhosis.
The first author of the study Tracey G. Simon said, “This is the first nationwide cohort study with detailed liver histology data to confirm that NAFLD contributes to an increased risk of all-cause mortality. These findings should be used to develop more targeted interventions designed to reduce mortality, in patients with NAFLD. We need public health strategies that prevent both extra-hepatic cancer and NAFLD progression to cirrhosis, for this rapidly growing population.”
As this study builds on the ESPRESSO cohort (Epidemiology Strengthened by Histopathology Reports in Sweden), which creates a nationwide gastrointestinal histopathology cohort, it also gives doctors a better understanding of the risks to their patients with all types of NAFLD. By targeting risks associated with mild fatty liver disease, patients may have more of a chance of preventing those risks or receiving treatments that could decrease the disease’s severity going forward.
More research is needed to understand the different risks associated with the severity of NALFD. As this study has found, even mild fatty liver disease can increase the chance of mortality, so people need to understand why maintaining a healthy lifestyle to deter illness and disease is so important.