A simplified psychometric evaluation for the diagnosis of minimal hepatic encephalopathy

Background & aims: The psychometric hepatic encephalopathy score (PHES), which includes 5 psychometric tests, is a standard for the diagnosis of minimal hepatic encephalopathy (HE). We investigated whether a simplified PHES (SPHES) is as useful as the whole PHES.

Methods: The PHES was determined for 79 cirrhotic patients (the training group), who were followed up for the development of overt HE. Backward logistic regression was performed by eliminating stepwise variables--removal did not impair regression. A separate series of 65 patients was used as a validation group.

Results: The PHES was abnormal in 45 patients. The SPHES, determined from the digit symbol, serial dotting, and line tracing tests, did not differ significantly from the full PHES; 24 of the 79 patients developed overt HE. The likelihood of developing overt HE was higher among patients with an abnormal PHES (log-rank P = .003) or SPHES (P = .004). By using Cox regression and model for end-stage liver disease scores to analyze data from patients with previous HE and transjugular intrahepatic portosystemic shunts, PHES (relative risk, 4.16; P = .003) and SPHES (relative risk, 3.70; P = .004) were the only variables associated with the development of overt HE. The accuracy of the SPHES was confirmed in the validation group.

Conclusions: A simplified PHES is as good as the PHES in diagnosing minimal HE and in predicting the occurrence of overt HE.