Hepatic encephalopathy, a major complication of cirrhosis, is a clinical syndrome characterized by mental status changes in patients with severe hepatic insufficiency. Hormonal disorders and circadian rhythm abnormalities are often associated with liver disease, and severity of these disorders is related to liver disease severity and duration. The role of melatonin is critical, as diurnal melatonin rhythm disruption may significantly contribute to circadian function alterations. However, there is very limited data relating these abnormalities with cirrhosis severity and hepatic encephalopathy
A research article to be published on 14 July 2008, in the World Journal of Gastroenterology addresses this question. In this article, they analyzed the correlation between pituitary hormone and melatonin circadian rhythms with clinical performance.
They found that melatonin rhythm abnormalities are more severe as cirrhosis progresses, and abnormal melatonin and pituitary hormone patterns are found before hepatic encephalopathy develops. As melatonin is a major determinant of important circadian rhythms in humans, an improved understanding of melatonin could have significant implications not only for cirrhosis patients, but also for the general public.
This is an important study because it shows that abnormal pituitary hormone and melatonin circadian secretion patterns are present in cirrhosis before hepatic encephalopathy develops, and also that melatonin circadian rhythm abnormalities correlate with liver disease severity. More importantly, these abnormalities could be an early indicator of hepatic encephalopathy.