Minimal hepatic encephalopathy characterized by parallel use of the continuous reaction time and portosystemic encephalopathy tests

Minimal hepatic encephalopathy (MHE) is a frequent complication to liver cirrhosis that causes poor quality of life, a great burden to caregivers, and can be treated. For diagnosis and grading the international guidelines recommend the use of psychometric tests of different modalities (computer based vs. paper and pencil). To compare results of the Continuous Reaction time (CRT) and the Portosystemic Encephalopathy (PSE) tests in a large unselected cohort of cirrhosis patients without clinically detectable brain impairment and to clinically characterize the patients according to their test results. The CRT method is a 10-minute computerized test of a patient's motor reaction time stability (CRTindex) to 150 auditory stimuli. The PSE test is a 20-minute paper-pencil test evaluating psychomotor speed. Both tests were performed at the same occasion in 129 patients. Both tests were normal in only 36 % (n = 46) of the patients and this group had the best quality of life, a normal CRP, a low risk of subsequent overt HE, and a low short term mortality. Either the CRT or the PSE test was abnormal in a total of 64 % of the patients (n = 83), the CRT in 53 % (n = 69) and the PSE in 34 % (n = 44). All these patients had a poorer quality of life, low-grade CRP elevation, moderate risk for subsequent overt HE, and a higher than 20 % short term mortality. Both tests were abnormal in 23 % (n = 30) of the patients and this group had more advanced cirrhosis and a 40 % short-term mortality. One of the tests was abnormal in the majority of the patients but concordant in only 60 %. Most cirrhosis patients seem to have impairments of different cognitive domains and more domains with advancing disease. Two abnormal tests identified patients with an increased risk of overt HE and death.