Original Contribution
The American Journal of Gastroenterology (2007) 102, 754–760; doi:10.1111/j.1572-0241.2007.01048.x
Inhibitory Control Test Is a Simple Method to Diagnose Minimal Hepatic Encephalopathy and Predict Development of Overt Hepatic Encephalopathy
Jasmohan S Bajaj MD1, Kia Saeian MD1, Matthew D Verber BS2, Darrell Hischke PhD1, Raymond G Hoffmann PhD3, Jose Franco MD1, Rajiv R Varma MD1 and Stephen M Rao PhD4
- 1Division of Gastroenterology and Hepatology, Medical College of Wisconsin, Milwaukee, Wisconsin
- 2General Clinical Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin
- 3Department of Biostatistics, Medical College of Wisconsin, Milwaukee, Wisconsin
- 4Department of Neurology, Medical College of Wisconsin, Milwaukee, Wisconsin
Correspondence: Jasmohan S Bajaj, MD, Division of Gastroenterology and Hepatology, Medical College of Wisconsin, 9200 W Wisconsin Ave, Milwaukee, WI 53226.
Received 22 July 2006; Accepted 26 October 2006.
Abstract
OBJECTIVES:
To compare inhibitory control test (ICT), a simple/rapid test of attention, to a standard psychometric battery (SPT) to diagnose minimal hepatic encephalopathy (MHE) and predict development of overt hepatic encephalopathy (OHE) in cirrhotic patients.
METHODS:
Fifty nonalcoholic cirrhotics and 50 age/educational-status-matched controls were given ICT and SPT in the same sitting. Performance impaired beyond two standard deviations of controls was considered MHE in cirrhotics. ICT results (lure/target response and lures/person) were compared between controls and cirrhotics and within cirrhotics with/without MHE. Receiver-operating characteristic analysis was used to study ICT for MHE diagnosis. Twenty subjects were administered SPT and ICT twice to assess test–retest reliability. All cirrhotics were followed routinely for the development of OHE.
RESULTS:
Cirrhotics performed worse than controls on SPT and ICT. Using SPT, 39 cirrhotics had MHE. ICT was administered faster than SPT (15 vs 37 min). Cirrhotics with MHE had significantly higher lure (28% vs 3%) and lower target response (91% vs 96%) compared with those without MHE. Lure/person >5 had 90% sensitivity/specificity for MHE diagnosis. AUC for receiver-operating characteristic for lures alone was 95.8%. Lure and target responses were highly correlated (r = 0.9) between sessions showing high test–retest reliability. Five (10%) patients developed OHE on f/u of 26 
10 months; all five had been diagnosed with MHE using ICT and SPT. None of the five patients with discordant results on SPT and ICT developed OHE.
CONCLUSIONS:
ICT has good sensitivity/specificity for MHE diagnosis, is reliable and is equivalent to SPT for predicting OHE development.
