For centuries, physicians and medical historians have studied multiple sclerosis and its symptoms (Murray 2005). Historical accounts of these symptoms, including fatigue, are well-documented. In one of the first documented cases of multiple sclerosis in the medical literature, Charles Prosper Ollivier d’Angers, a 19th century medical practitioner, described a 20-year-old patient who felt “tired and languid” prior to experiencing his first multiple sclerosis relapse (Murray 2005). Personal accounts from one of the earliest documented patients with multiple sclerosis, Augustus d’Este, grandson of King George III, chronicled his relapses and symptoms from 1822 to 1848. In his writings, he described symptoms reminiscent of fatigue in the context of endurance and loss of strength (d'Este and Firth 1948). Alan Stevenson, a 19th century Scottish poet, scholar, and lighthouse keeper, described episodes of “drowsiness” as well as tiredness in his writings (Murray 2005).
Despite early recognition, the complexity and subjective nature of fatigue has precluded a unified definition to date. Common definitions include a “sense of exhaustion,” “lack of energy,” or “tiredness” (Krupp et al 1988). The Fatigue Guidelines Development Panel of the Multiple Sclerosis Council for Clinical Practice Guidelines defined fatigue as “a subjective lack of physical and/or mental energy that is perceived by the individual or caregiver to interfere with usual or desired activity” (Fatigue Guidelines Development Panel of the Multiple Sclerosis Council for Clinical Practice Guidelines 1998).