Q
What is the connection, if any, between fatty liver and sleep apnea?
Asked by Mike Peterson • 70 votes
A
Fatty liver disease, or the buildup of fat in the liver, and sleep apnea, marked by snoring and interruptions of breathing at night, share some things in common. The two conditions frequently strike people who are overweight or obese. Each afflicts tens of millions of Americans, and often the diseases go undiagnosed.
Researchers used to believe that sleep apnea and fatty liver were essentially unrelated, even though they occur together in many patients. But now studies suggest that the two may be strongly linked, with sleep apnea directly exacerbating fatty liver.
In a study published last year in the journal Chest, researchers looked at 226 obese middle-aged men and women who were referred to a clinic because they were suspected of having sleep apnea. They found that two-thirds had fatty liver disease, and that the severity of the disease increased with the severity of their sleep apnea.
A study last year in The Journal of Pediatrics found a similar relationship in children. The researchers identified sleep apnea in 60 percent of young subjects with fatty liver disease. The worse their apnea episodes, the more likely they were to have fibrosis, or scarring of the liver.
Though it is still somewhat unclear, some doctors suspect that the loss of oxygen from sleep apnea may increase chronic inflammation, which worsens fatty liver. Although fat in the liver can be innocuous at first, as inflammation sets in, the fat turns to scar tissue, and that can lead to liver failure.
Ultimately, it is clear that people who have particularly severe apnea should be checked for fatty liver disease, said Dr. Rohit Kohli, a co-director of the fatty liver disease center at Cincinnati Children’s Hospital Medical Center.
“If you have documented severe sleep apnea episodes during the night, you should be screened,” he said, “because we have enough evidence now from studies showing that one goes hand in hand
with the other. And when you reverse one disease, it will probably help the other.”