Low liver fat, high abdominal fat combo may foretell CHD risk

Distribution of body fat can affect a person’s risk of coronary heart disease (CHD), suggests a study presented at the AASLD 2020 Liver Meeting, which shows that people with high abdominal fat but low liver fat have an increased risk of CHD events than those with other fat distribution.

“Our knowledge of patient risk for disease is limited when we restrict our assessment to single, isolated fat depots,” said lead investigator Dr Jennifer Linge at AMRA Medical AB in Linköping, Sweden.

High fat stores in both the abdomen and liver are common in individuals with metabolic disease such as type 2 diabetes, she explained. While excess deep body fat has been known to be related to heart disease, the association between liver fat and cardiometabolic disorders remains unknown.

Findings from the current study suggest that regulation of liver triglyceride plays a vital role in heart health, especially for people with discordant abdominal and liver fat levels.

The study involved 12,276 individuals (mean age 62.6 years, 51 percent female, BMI 26.6) who underwent imaging for visceral adipose tissue (VAT; abdominal fat) and liver fat (LF) fraction. The participants were categorized into four groups based on their fat distribution: those with both high VAT and LF, both low VAT and LF, high VAT but low LF, and low VAT but high LF. [AASLD 2020, abstract 0089]

During a mean follow-up of 1.3 years, CHD incidence was highest in participants with high VAT but low LF (2.4 percent), followed by those with both high VAT and LF (1.6 percent). CHD incidence was similar for the remaining two groups, at 1.1 percent and 0.9 percent for those with both low VAT and LF and those with low VAT but high LF, respectively.

Specifically, the high VAT/low LF group were more than twice as likely to have incident CHD compared with the reference group of participants with both low VAT and LF (odds ratio [OR], 2.33; p<0.001).

Although the magnitude of association between high VAT/low LF and increased CHD risk became smaller after adjusting for age and BMI, the association remained significant (OR, 1.65; p=0.034).

There was no association between having low VAT/high LF and CHD risk.

“These results indicate the importance of proper liver triglyceride regulation in the context of visceral adiposity,” said Linge. “Understanding patients’ individual way of storing fat can be valuable in developing targeted prevention and treatment strategies.”

“When developing treatments for NAFLD, a decrease in liver fat alone may not be sufficient to lower of a patients’ cardiometabolic risk. In fact, it seems that a decrease in liver fat without a resolution of visceral obesity may put the patient at a greater risk of developing heart disease. This is what we want to investigate further,” she pointed out.