Chronotypology and melatonin alterations in minimal hepatic encephalopathy

Twenty-six cirrhotic patients enrolled in the study and thirteen patients without liver or central nervous system disease served as controls. All patients had full clinical and biochemical evaluation, chronotypology analysis, neurological evaluation, melatonin profile and quality of life assessment.Cirrhotic patients with minimal encephalopathy exhibit melatonin secretion abnormalities. Cirrhosis patients with more severe hepatic insufficiency (Child-Pugh score > 5) had significantly (p < 0.04) lower evening melatonin levels compared to patients with less severe insufficiency (Child-Pugh score = 5).Chronotypology analysis revealed Morning Type pattern in 88% of cirrhosis patients.The presence of abnormal plasma melatonin levels before the onset of clinical hepatic encephalopathy, and the finding that patients with more severe cirrhosis have lower evening melatonin levels are the most important findings of this study. Despite these melatonin abnormalities, chronotypology revealed Morning Type pattern in 23 of 26 cirrhosis patients. We believe these findings are important and deserve further study.Melatonin abnormalities occur in cirrhosis patients without clinical encephalopathy, are related to liver insufficiency severity, may influence chronotypology patterns, and certainly deserve further investigation.Most physiological and behavioral human variables, including sleep and wakefulness, endocrine function, thermoregulation and metabolism exhibit circadian patterns. Circadian rhythms are controlled by central neural pacemakers, of which the Suprachiasmatic Hypothalamic Nucleus (SCN) is the best characterized [1-5] Hepatic encephalopathy, a major cirrhosis complication, is a clinical syndrome characterized by mental status abnormalities in patients with severe hepatic failure. In contrast, the term "minimal (subclinical) hepatic encephalopathy" describes milder disturbances of biological parameters such as sleep, and abnormalities in every day life activities, in the