Minimal hepatic encephalopathy: A vehicle for accidents and traffic violations

OBJECTIVES: MHE patients have impairment on driving tests. However, it is unclear whether this impairment is restricted to the testing environment or is associated with increased traffic violations and/or motor vehicle accidents. METHODS: An anonymous driving history and driving behavior questionnaire (DBQ: self-scored, best score 104), coded according to MHE status, was sent to 200 cirrhotics without overt hepatic encephalopathy and 100 age/education-matched controls. The questionnaire inquired about demographics, alcohol/illegal drug use, and violations/accidents within 1 and 5 yr. The cirrhotics had been divided into those with MHE (MHE+), without MHE (MHE-), and those not tested for MHE because of psychoactive drug use, on a previous study. RESULTS: Cirrhotics versus controls had similar driving duration, alcohol/illegal drug use but significantly higher percentage with violations within both 1 and 5 yr (25% vs 4% [5 yr]), 13% vs 2% [(1 yr]), accidents (17% vs 4% [5 yr]), 9% vs 1% [1 yr]), and both (34% vs 7% [5 yr], 18% vs 3% [ 1 yr]). MHE+ cirrhotics had significantly higher percentage with violations (36% [5 yr], 21% [1 yr]), accidents (33% [5 yr]), 17% [1 yr]), and both (53% [5 yr], 33% [1 yr]) versus other cirrhotics. DBQ score was significantly lower in cirrhotics than controls (92 vs 99). Within cirrhotics, DBQ score was highest in MHE-versus other groups. MHE+ status was the only risk factor (odds ratios: 4.2-7.6) for violations and for accidents on multivariate logistic regression. CONCLUSIONS: Cirrhotics have a higher self-reported occurrence of violations and accidents compared to controls. MHE+ a is strong predictor for violations and accidents. Prospective studies investigating the effect of MHE treatment on violations and accidents are warranted.