Functional movement disorder (FMD), the motor-dominant subtype of functional neurological disorder, is a complex neuropsychiatric condition. Patients with FMD also manifest non-motor symptoms. Given that patients with FMD are diagnosed based on motor phenotype, the contribution of non-motor features to the neuropsychiatric syndrome is not well characterized. The objective of this hypothesis-generating study was to explore potential novel, neuropsychiatric FMD phenotypes by combining movement disorder presentations with non-motor comorbidities including somatic symptoms, psychiatric diagnoses, and psychological traits.

This retrospective chart review evaluated 158 consecutive patients with a diagnosis of FMD who underwent deep phenotyping across neurological and psychiatric domains. Demographic, clinical, and self-report features were analyzed. A data-driven approach using cluster analysis was performed to detect patterns when combining the movement disorder presentation with somatic symptoms, psychiatric diagnoses, and psychological factors. These new neuropsychiatric FMD phenotypes were then tested using logistic regression models.

Distinct neuropsychiatric FMD phenotypes emerged when stratifying by episodic vs. constant motor symptoms. Episodic FMD was associated with hyperkinetic movements, hyperarousal, anxiety, and history of trauma. In contrast, constant FMD was associated with weakness, gait disorders, fixed dystonia, activity avoidance, and low self-agency. Pain, fatigue, somatic preoccupation, and health anxiety were common across all phenotypes.

This study found patterns spanning the neurological-psychiatric interface that indicate that FMD is part of a broader neuropsychiatric syndrome. Adopting a transdisciplinary view of illness reveals readily identifiable clinical factors that are relevant for the development and maintenance of FMD.

The aim of this scoping review is to describe the characteristics of patients requiring admission to hospital for functional neurological disorder (FND), assess interventions provided, and evaluate outcomes in the context of acute hospital presentation or elective admission with chronic symptoms (>3 months).

A scoping review was performed. Included articles described adult patients admitted with FND to an inpatient care setting. Articles focusing on psychogenic non-epileptic attacks (PNEA) were excluded.

The search strategy identified 1963 citations. A total of 34 articles met inclusion criteria, with 458 patients (66% female) described. The pooled mean age of patients in all studies was 40.6 years. Eleven studies described patients with acute presentation, and 16 studies described patients with chronic FND symptoms admitted to the hospital. Motor symptoms were most common. Interventions were most commonly physiotherapy and psychotherapy. Most studies reported partial or complete resolution of symptoms.

This scoping review summarizes the literature on the characteristics of patients admitted to the hospital, both with acute and chronic symptoms, for inpatient treatment of FND. When comparing patients with acute to those with chronic symptoms, we found that acute presentations were older (46.9 vs. 43.7 years) and had a higher representation of men (33% vs. 30%). Those presenting with chronic symptoms were more likely to not improve or relapse. We postulate that early diagnosis and inpatient rehabilitation could have a positive impact on outcomes for patients with FND.