Prevalence and prognostic value of quantified electroencephalogram (EEG) alterations in cirrhotic patients

Background/Aims: The electroencephalogram (EEG) is frequently altered in cirrhotic patients. We, therefore, performed a study to ascertain the features and the prognosis of cirrhotic patients without current overt hepatic encephalopathy (OHE) who have EEG alterations. Methods: A series of 296 consecutive cirrhotic patients who had undergone quantified-EEG was studied. The median follow-up was 442 days, 128 patients had bouts of OHE and 78 patients died from liver-related causes. Another group of 124 cirrhotic patients with a median follow-up of 223 days was examined to validate the prognostic model. Results: EEG alterations were detected in 38% of the patients. The prevalence of EEG alterations was associated with the severity of cirrhosis (class B: odds ratio (OR)=2.3, 95% confidence interval (CI)=1.2–4.7; class C: OR=3.5, 95% CI=1.6–7.7), but not with the aetiology (alcoholic vs. non-alcoholic: OR=0.9; 95% CI=0.5–1.5). The EEG predicted the occurrence of OHE (χ2=26; P<0.001) and mortality (χ2=34; P<0.001), also adjusting for Child–Pugh class by a multivariate analysis. In the patients with a Child–Pugh score of ≥8, the EEG discriminated between those patients with a higher 1-year risk of OHE (hazard ratio (HR)=3.3, 95% CI=1.8–6.1) and death (HR=3.1, 95% CI=1.7–5.6). Conclusions: In conclusion, quantified-EEG had a prognostic value for the occurrence of bouts of OHE and mortality in cirrhotic patients.