Liver cirrhosis is the seventh leading cause of death in the United States, taking 25,000 lives per year. It is often the result of alcohol over-consumption or exposure to hepatitis C, either of which can damage the liver and prevent it from filtering toxins. These toxins then accumulate in the blood stream and eventually reach the brain where they disrupt neurological and mental performance, a condition known as hepatic encephalopathy.

Individuals with cirrhosis are also susceptible to a change in heart rhythm (decreased heart rate variability). Since cirrhosis, hepatic encephalopathy and heart rate variability are known to be associated with inflammation, researchers have examined what role cytokines (inflammatory molecules) play.

A new study from The American Physiological Society suggests that these cytokines can lead to both the neurological and cognitive abnormalities and changes in heart rhythm in patients with cirrhosis. The results of the study may also apply to other conditions where heart rate variability is also decreased, such as bipolar disorder and post-menopausal depression.

The study, "Decreased heart rate variability in patients with cirrhosis relates to the presence and severity of hepatic encephalopathy," was carried out by Ali R. Mani, Sara Montagnese, Clive D. Jackson, Christopher W. Jenkins, Ian M. Head, Robert C. Stephens, Kevin P. Moore and Dr. Morgan. All are affiliated with the University College London Medical School, with the exception of Mr. Jackson, who is with the Royal Free Hospital, London. The study appears in The American Journal of Physiology-Gastrointestinal and Liver Physiology.

Three measurements

The study involved 80 patients suffering cirrhosis of the liver…