Quantitative psychometric testing and subclinical hepatic encephalopathy--comparative study between encephalopathic and non-encephalopathic patients with liver cirrhosis.

Six quantitative psychometric tests were performed on 51 healthy subjects, 19 cirrhotic patients with subclinical hepatic encephalopathy (SHE), 32 cirrhotic patients without SHE, and 26 patients with other diseases. Strong correlations between age and the results of all the psychometric tests were observed in the healthy subjects (p less than 0.005). Sex and etiology of liver cirrhosis did not affect the test results. SHE patients, compared with non-SHE and health subjects, presented impairment in the ability to perform the tests, even in the absence of obvious clinical and electroencephalogram findings. In SHE patients, trailmaking test A (TMT A) yielded the highest frequency of abnormal values, 63%. TMT A results were abnormal in 80% of SHE patients with abnormal scores in other tests, and thus it seemed to be the most sensitive test. Liver function tests did not correlate with psychometric testing in any of the groups. Blood ammonia levels in SHE patients with abnormal TMT A scores correlated with TMT A scores (r = 0.752, p less than 0.01); this was not the case in SHE nor non-SHE patients with normal TMT A results. These data demonstrate the usefulness of psychometric tests in detecting SHE.