Functional Neurological Disorder Does Not Shorten Lifespan
FND does not cause death or reduce life expectancy, and mortality rates are not elevated compared to the general population. 1
Core Prognostic Understanding
FND is fundamentally different from degenerative or structural neurological diseases because it does not cause permanent structural damage to the nervous system—symptoms arise from a potentially reversible miscommunication between the brain and body, not from irreversible neurological injury. 2 This distinction is critical: FND is not a life-threatening or degenerative condition. 1
Impact on Quality of Life Rather Than Mortality
While FND does not affect lifespan, it profoundly impacts quality of life and functional status:
The burden of FND manifests as high levels of distress, disability, unemployment, and reduced quality of life—reflecting symptom burden and associated stigma rather than a life-threatening disease process. 2
Symptoms can present acutely and resolve quickly, or can be long-lasting with significant functional impairment. 1
Many patients experience severe disability from motor symptoms (weakness, movement disorders), seizure-like events, sensory changes, and cognitive deficits that are genuine and disabling despite being functional rather than structural. 2
Secondary Complications That Require Monitoring
The main risks to health in FND come from secondary complications of the disorder, not from FND itself:
Prolonged immobility or reduced activity can lead to deconditioning and muscle atrophy, which become progressively more difficult to reverse over time. 2
Functional dysphagia can result in unintended weight loss, malnutrition, and social withdrawal. 2
Maladaptive movement patterns and premature use of assistive devices can create new musculoskeletal problems including secondary pain syndromes. 2
High rates of obesity (36.9%, higher than the general population) are associated with increased pain, fatigue, and sleep difficulties, with frequent weight gain occurring after diagnosis. 3
Treatment Outcomes and Reversibility
The potential for symptom reversal distinguishes FND from conditions that do affect lifespan:
60-96% of patients report improvement after intervention, with Clinical Global Impression-Improvement scores typically falling in the minimally to much improved range. 2, 1
Measurable improvements occur across multiple domains including mobility, depression, and quality of life, with realistic timelines for improvement being 12-25 months with multidisciplinary intervention. 2, 1
Symptoms remain potentially reversible throughout the disease course with appropriate treatment. 2
Common Pitfall to Avoid
Do not conflate the significant disability and reduced quality of life experienced by FND patients with shortened lifespan. The high burden of psychological comorbidity (anxiety, depression, dissociation), physical symptom burden, and reduced quality of life create a vicious cycle of disability 2, but these factors reflect disease burden rather than mortality risk. The key clinical message is that early diagnosis and multidisciplinary treatment focused on rehabilitation can improve outcomes without concerns about life expectancy. 2, 1