Biopsychosocial prognostic indicators in Functional Neurological Disorder: A systematic review

Abstract

Background

Functional Neurological Disorder (FND) may result in significant disability. Biopsychosocial and contextual factors contributing to health outcomes in FND remain unclear.

Purpose

To ascertain the current evidence relating to biopsychosocial and contextual factors of prognostic relevance in adults with FND.

Methods

A systematic review was conducted. Studies of adults with FND were included. Methodological quality was assessed using the Joanna Briggs Institute checklist for cohort studies. A best-evidence synthesis approach was applied to consider the quantity and consistency of findings. Outcomes measured were mapped to the biopsychosocial domains of the International Classification of Functioning, Disability and Health framework.

Findings

The search yielded 6019 references. Thirty studies (3000 participants) examining 2309 people with FND met inclusion criteria. Ten were deemed high methodological quality and 17 medium quality. Biologically, age was unrelated to outcomes. Psychologically, a history of psychiatric treatment, somatisation and alexithymia were associated with negative outcomes. Socially, there was strong evidence that workforce participation was associated with better outcomes. Seizure frequency and illness duration were characteristics unrelated to outcomes. Factors associated with an individual were examined more often than broader systemic contextual factors.

Conclusions

This review summarises existing knowledge around biopsychosocial prognostic indicators of recovery in adults with FND. Workforce participation is associated with better health outcomes in FND. A change in seizure frequency may not translate to participation in life roles. There was limited research investigating the impact of systemic contextual factors. A more consistent approach in this research area would further reveal the true state of phenomena.