Liver and Biliary Tract
Subject Category: Liver and Biliary Tract
Am J Gastroenterol 2009; 104:898–905; doi:10.1038/ajg.2009.7; published online 10 March 2009
The Effect of Fatigue on Driving Skills in Patients With Hepatic Encephalopathy
Jasmohan S Bajaj MBBS, MD, MS1, Muhammad Hafeezullah MBBS4, Yelena Zadvornova MD4, Eric Martin MD4, Christine M Schubert PhD2, Douglas P Gibson Psy D, MPH3, Raymond G Hoffmann MD5, Arun J Sanyal MBBS, MD1, Douglas M Heuman MD1, Thomas A Hammeke PhD6 and Kia Saeian MD, MS4
- 1Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, Virginia Commonwealth University and McGuire VA Medical Center, Richmond, Virginia, USA
- 2Department of Biostatistics, Virginia Commonwealth University and McGuire VA Medical Center, Richmond, Virginia, USA
- 3Division of Psychology, Department of Psychiatry, Virginia Commonwealth University and McGuire VA Medical Center, Richmond, Virginia, USA
- 4Division of Gastroenterology and Hepatology, Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
- 5Department of Pediatrics and Biostatistics, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
- 6Department of Neurology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
Correspondence: Jasmohan S. Bajaj, MBBS, MD, MS, Division of Gastroenterology, Hepatology and Nutrition, Virginia Commonwealth University and McGuire VA Medical Center, 1201 Broad Rock Boulevard, Richmond, Virginia 23249, USA. E-mail: Jasmohan.bajaj@va.gov
Received 23 September 2008; Accepted 27 October 2008; Published online 10 March 2009.
Abstract
OBJECTIVES:
Hepatic encephalopathy, both overt (OHE) and minimal (MHE), is associated with poor quality of life and fatigue. The aim of this study was to define the effect of fatigue on driving skills in MHE and OHE patients.
METHODS:
Cirrhotics and age/education-matched controls were administered a psychometric battery of tests to diagnose MHE. Cirrhotics with recent OHE on lactulose were also included. All subjects underwent a driving simulation; to assess fatigue, the second half performance was compared with the first half of the simulation. The outcomes were collisions, speeding, road excursions, and center crossings. Actual driving-associated fatigue was assessed by the American Medical Association (AMA) driver survey.
RESULTS:
A total of 100 cirrhotics (51 MHE, 27 no MHE, and 22 OHE) and 67 controls were included. A significantly higher proportion of OHE and MHE patients admitted to fatigue after actual driving on the AMA survey compared with no MHE patients (P=0.02). All patients who admitted to fatigue and none who denied fatigue on the AMA survey had simulator collisions. Psychometric and simulator performance in treated OHE patients was similarly impaired to MHE patients despite therapy. Within groups, a significant increase in collisions, speeding, and center crossings in the second half (P=0.01) was seen only in MHE patients.
CONCLUSIONS:
Psychometric and simulator performance in patients with recent OHE on treatment is similarly impaired as that of untreated MHE patients. Simulator performance in MHE worsens over time with fatigue. OHE and MHE patients had a higher rate of actual driving-associated fatigue on the AMA survey, which was significantly predictive of simulator collisions.
