Figure 1.

Fatigue as a construct can be described along three axes—motor, cognitive, affective. The performance and integrity of the muscles and the neuromuscular junction is the measurable part and has received the maximum attention in recent years. The cognitive and affective domains are similar to other disease states in which fatigue is a prominent symptom. These domains are potential targets for pharmacotherapy, although large clinical trials using specific agents have not been performed in patients with chronic liver disease. Patients with advanced liver disease may have hepatic encephalopathy, which makes interpretation of cognitive and affective changes difficult.