Performance characterization of a novel electronic number connection test to detect minimal hepatic encephalopathy in cirrhotic patients
Background and aim Hepatic encephalopathy (HE) is a frequent complication of cirrhosis, characterized by cognitive deficits that negatively impact patients' quality of life. The mild, minimal hepatic encephalopathy (mHE) can only be detected by psychometric tests and early mHE detection can prevent more severe complications or even survival times. Here, we aimed to investigate the feasibility and validity of the novel-developed electronic number connection test (eNCT), which is designed as a fast and easy-to-perform mHE patient self-test. Methods The eNCT design was inspired by the paper-pencil number connection test version A, showing 25 numbers on the screen (1-25), in a random order. The time required to tap on all digits in the correct order was measured. A total of 238 individuals (112 patients with liver cirrhosis) were enrolled in this study and eNCT times were compared with well-established paper-pencil tests. The Psychometric Hepatic Encephalopathy Score test battery was used to detect mHE and cut-off values for mHE detection by the eNCT were defined. Results Overall, cirrhotic patients showed significantly slower test completion times compared with control participants. The eNCT performance was inversely correlated with Psychometric Hepatic Encephalopathy Score test performance in cirrhotic patients, independent of the HE status. Thirty cirrhotic patients fulfilled the mHE criteria and receiver operating characteristic curve analysis showed high sensitivity (>82%) and specificity (>85%) for mHE detection. Finally, the eNCT showed excellent test-retest reliability (intraclass correlation coefficient=0.94). Conclusion The novel eNCT is a reliable HE self-test to monitor cognitive function and detect cognitive impairment in cirrhotic patients.