Predictors of minimal hepatic encephalopathy in patients with cirrhosis

ABSTRACT

Minimal hepatic encephalopathy [MHE] impairs patient's daily functioning of life. Predictors of MHE in cirrhotic patients have not been evaluated. A total of 200 cirrhotic patients [Child A, 74[37%]; Child B, 72[36%]; Child C, 54[27%]] were evaluated by psychometry, P300 auditory event-related potential [P300ERP] and critical flicker frequency [CFF]. MHE was diagnosed by abnormal psychometry [>2S.D.] and P300ERP [>2.5 S.D.]. Univariate and multivariate logistic regression analyses were performed to determine the predictors of MHE. Eighty-two [41%] patients were diagnosed to have MHE - 26/74 [35%] in Child a, 26/72 [36%] in Child B and 30/54 [56%] in Child C. Ninety-seven [48.5%] patients had abnormal psychometric tests, and 96 [48%] had prolonged P300ERP [>385 ms]. Sixteen [16.5%] patients with abnormal psychometry had P300ERP > 358 ms. One hundred and three patients had CFF value <39 Hz with specificity of 86.6% and sensitivity of 72.9% for MHE. Model for end-stage liver disease [MELD] [17.9 +/- 5.7 vs. 13.4 +/- 4.2, P=0.005], Child-Turcotte-Pugh [CTP] score [8.4 +/- 2.5 vs. 7.7 +/- 2.2, P=0.02], ammonia [104.8 +/- 37.9 vs. 72.5 +/- 45.2 micro mol/L, P=0.001] and CFF [37.0 +/- 2.8 vs. 41.0 +/- 3.4 Hz, P=0.001] were significantly higher in MHE as compared to non-MHE patients. Ninety-one [45.5%] patients had MELD>15.5, 115 [57.5%] had CTP score> 7.5, while 93 [46.5%] had venous ammonia >84.5 micro mol/L. On univariate analysis, MELD [8.52[95% CI, 4.11-16.26; P=0.001]], CFF [17.34[95% CI, 8.16-36.85; P=0.001]] and venous ammonia [7.80 [95% CI, 4.11-14.81; P= 0.003]] were associated with MHE; while CTP score [1.51[95% CI, 0.85-2.69; P=0.30]] was not significant. On multivariate analysis, MELD, CFF and venous ammonia were predictive of MHE. Prevalence of MHE in this study was 41%; and MELD>15.5, CFF< 39 Hz and venous ammonia >84.5 micro mol/L were predictive of MHE