Sleep disorders and brain MRI as early indicators of subclinical hepatic encephalopathy

Cirrhotic patients with hepatic encephalopathy have significant impairment of their daily activities. Sleep disturbances and increased signal on T1-weighted brain Magnetic Resonance Imaging (MRI) are commonly encountered in this clinical entity. The prevalence of these abnormalities in patients with subclinical encephalopathy is unknown.

Sleep history and brain MRI were evaluated in 26 cirrhotic individuals with no evidence of encephalopathy. Thirteen patients without liver dysfunction or signs of neurological impairment served as a control group.

Sleep disturbances were found in 24 of 26 cirrhotic patients (92.3%), whereas 18 of them (69.2%) had brain MRI abnormalities (p<0.05 by McNemar's test). Among the control group, 1 of 13 patients had sleep disorders, whereas none exhibited abnormal MRI (both p<0.001 by chi2 compared to study group). Increased bilirubin and globulin levels, and decreased albumin levels were found to have a significant correlation to brain MRI abnormalities among cirrhotic patients.

Sleep disturbances are emerging as a sensitive sign of subclinical encephalopathy in cirrhotic patients. A major role of brain MRI is also recognized, as abnormal images are highly prevalent in this clinical entity. Furthermore, the level of MRI abnormalities appears to be in concordance with the abnormal liver function tests.