For the first time, researchers have shown that a bi-directional relationship exists between fatty liver disease and cardiovascular disease. Fatty liver disease can lead to increased cardiovascular disease risk and vice versa.

The findings, which appear online in the Journal of Hepatology, are important in understanding the link between fatty liver disease and cardiovascular disease, which continues to be one of the major causes of morbidity and mortality worldwide.

Due to the increased prevalence of obesity, non-alcoholic fatty liver disease has become the most common liver disease in the U.S., affecting 20-30 percent of the adult population. Obesity is also an independent risk factor for cardiovascular disease — so both diseases exist in many patients. Previous studies have shown that there is a link between fatty liver and cardiovascular disease however it is not fully understood if fatty liver disease precedes or develops after cardiovascular disease.

Using data from participants in the Framingham Heart Study, researchers saw that individuals with fatty liver disease developed cardiovascular diseases such as high blood pressure and type 2 diabetes within six years. In a parallel analysis, individuals with high blood pressure, type 2 diabetes, or high triglycerides had a higher likelihood of developing fatty liver disease.

“In our study, we observed a bi-directional association between fatty liver and cardiovascular disease,” explained corresponding author Michelle Long, MD, assistant professor of medicine at Boston University School of Medicine (BUSM), who also is a gastroenterologist at Boston Medical Center (BMC). “We observed that fatty liver was an important factor in the development of high blood pressure and diabetes and the opposite also stands true – various cardiovascular diseases were associated with the development of fatty liver disease over six years,” she added.

Long believes this study highlights the need to develop both preventative and treatment strategies for fatty liver disease in order to improve the cardiovascular health of all people.