Fatigue across the CNS spectrum: a clinical review

Fatigue is reflected in a broad array of symptoms that can be particularly impactful in patients with central nervous system (CNS) disorders. Fatigue symptoms can present as core components of the underlying CNS disorder, as part of co-morbid medical conditions, as secondary to psychosocial stressors or physical or mental exertion, and/or secondary to the medications used to treat the disorders. The complex, multi-factorial etiology of fatigue symptoms can obscure the assessment and complicate the treatment intervention for the underlying primary CNS disorder. In this narrative clinical review, we focus on identification, assessment, and adjunctive pharmacological treatment of fatigue symptoms across five distinct CNS disorders. Given the potential impact of fatigue on function and quality of life, it is important to address this symptom as part of a comprehensive evaluation.