Identifying functional cognitive disorder: a proposed diagnostic risk model

A qualitative analysis of patients' day-to-day living with functional cognitive disorder (FCD)

PURPOSE

Functional cognitive disorder (FCD) is an increasingly recognised condition which causes significant disability and distress. While it is known to be associated with depression, anxiety and reduced functioning, like other functional neurological disorders it may be marred by stigma. To date, little is known about the lived experience of those with FCD.

MATERIALS & METHODS

As part of a randomised controlled feasibility trial of online group Acceptance and Commitment Therapy (ACT) for FCD we conducted in-depth qualitative interviews and utilised a thematic analysis approach to explore the challenges of living with FCD; how individuals cope with the symptoms; and their experiences of healthcare services.

RESULTS

We recruited six women and three men, with a median age of 54. They described living with FCD which included experiences of loss of identity, altered role, feelings of confusion, frustration and low self-esteem, stigma, social isolation, and dismissal by healthcare services. Nevertheless, suffers strove to find strategies to ameliorate their symptoms.

CONCLUSIONS

FCD is a common and disabling condition which like other functional neurological symptoms leads to altered sense of self and unsatisfactory interactions with others, including healthcare professionals. The diagnosis should be made on positive grounds, clearly explained, and potential therapies investigated.

Neurocognitive performance in functional neurological disorder: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

Cognitive complaints are common in functional neurological disorder (FND), but it is unclear whether objective neurocognitive deficits are present. This systematic review summarized validated/standardized cognitive test performance in FND samples across cognitive domains.

METHODS

Embase, PsycInfo and MEDLINE were searched from inception to 15 May 2023, combining terms for FND and cognitive domains (e.g., attention, memory, executive functioning). Studies included a range of FND phenotypes (seizures, motor, cognitive disorder, mixed), compared to healthy or clinical controls. Risk of bias was assessed with the modified Newcastle-Ottawa Scale and a qualitative synthesis/narrative review of cognitive performance in FND was conducted. Test performance scores were extracted, and random effects meta-analyses were run where appropriate. This review was registered on PROSPERO, CRD42023423139.

RESULTS

Fifty-six studies including 2260 individuals with FND were eligible. Although evidence for some impairments emerged across domains of executive functioning, attention, memory and psychomotor/processing speed, this was inconsistent across studies and FND phenotypes. Common confounds included group differences in demographics, medication and intellectual functioning. Only 24% of studies objectively assessed performance validity. Meta-analyses revealed higher scores on tests of naming (g = 0.67, 95% confidence interval [CI] 0.50, 0.84) and long-term memory (g = 0.43, 95% CI 0.13, 0.74) in functional seizures versus epilepsy, but no significant differences in working (g = -0.08, 95% CI -0.44, 0.29) or immediate (g = 0.25, 95% CI -0.02, 0.53) memory and cognitive flexibility (g = -0.01, 95% CI -0.29, 0.28).

CONCLUSIONS

There is mixed evidence for objective cognitive deficits in FND. Future research should control for confounds, include tests of performance validity, and assess relationships between objective and subjective neurocognitive functioning.

Psychiatric Etiologies and Approaches in Altered Mental Status Presentations: Insights from Consultation Liaison Psychiatry

Consultation liaison psychiatrists are frequently asked to evaluate patients with altered mental status (AMS). Psychiatrists have unique perspectives and approaches to care for confused patients, particularly optimizing facilitation of care and maintaining vigilance for diagnostic overshadowing. Psychiatrists also offer expertise in primary psychiatric illnesses that can overlap with AMS, and the most common etiology of AMS is delirium. In this article, we provide a consultation liaison psychiatrist perspective on AMS and related psychiatric conditions in addition to delirium. Manic and psychotic episodes have primary and secondary etiologies, with some symptoms that can overlap with delirium. Catatonia, neuroleptic malignant syndrome, and serotonin syndrome are potentially fatal emergencies, and require prompt index of suspicion to optimize clinical outcomes. Trauma sequelae, functional neurologic disorders, and dissociative disorders can present as puzzling cases that require psychiatric facilitation of care. Additionally, AMS is sometimes due to substance intoxication and withdrawal in the hospital. A nonstigmatizing approach to evaluation and management of delirium and AMS can ensure optimal patient care experiences and outcomes.

Characterisation of psychological and neurocognitive processes accompanying functional seizures

OBJECTIVES

To examine the relationship between clinical, psychological, and cognitive characteristics of adults with functional seizures.

METHODS

This study describes baseline characteristics of one-hundred and seven participants with a documented diagnosis of functional seizures recruited to the Re-PROGRAM randomised controlled trial. Participants completed a semi-structured interview, neuropsychological assessment, and questionnaire measures via Telehealth.

RESULTS

Participants reported low levels of trust in body sensations, high levels of negative ruminative thinking, dissociation, somatisation, anxiety, depression, severe levels of functional impairment, and poor quality of life. At a group level, they had normal neurocognitive function, including mental control, processing speed, attention, and executive function. Anxiety (73%), depression (68%), post-traumatic stress disorder (49%), migraine (63%) and chronic pain (52%) were common comorbidities. Forty-three percent reported a family history of dementia. Somatic symptoms were associated with depression, anxiety, dissociation, ruminative negative thinking, and lower scores on the 'Not-distracting' interoception scale. Poorer psychosocial functioning was associated with depression and dissociation. Reduced mental quality of life was associated with higher levels of depression, anxiety, dissociation, ruminative negative thinking, and lower scores on the 'Trusting' interoception scale. There were no associations between the clinical or psychological variables and seizure frequency or seizure classification. Neither cognitive impairment nor failure on effort testing were associated with the clinical or psychological factors, quality of life or psychosocial functioning.

SIGNIFICANCE

This study highlights the burden of psychiatric and physical comorbidity; and the relationship between psychological factors and functional impairment in a large cohort of patients with functional seizures despite normal cognitive function.

Measurement Properties of the Patient Health Questionnaire-15 and Somatic Symptom Scale-8: A Systematic Review and Meta-Analysis

Importance

The subjective experience of somatic symptoms is a key concern throughout the health care system. Valid and clinically useful instruments are needed.

Objective

To evaluate the measurement properties of 2 widespread patient-reported outcomes: the Patient Health Questionnaire-15 (PHQ-15) and Somatic Symptom Scale-8 (SSS-8).

Data Sources

Medline, PsycINFO, and Web of Science were last searched February 1, 2024.

Study Selection

English-language studies reporting estimates pertaining to factor analysis, taxometric analysis, internal consistency, construct validity, mean scores in relevant groups, cutoffs, areas under the receiver operating characteristic curves (AUROCs), minimal clinically important difference, test-retest reliability, or sensitivity to change.

Data Extraction and Synthesis

Search hits were reviewed by independent raters. Cronbach α, Pearson r, means, and between-group effect sizes indicative of sensitivity to change were pooled in random-effects meta-analysis. Study quality was assessed using 3 instruments. Reporting followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 reporting guideline.

Main Outcomes and Measures

Comprehensive overview of evidence pertaining to the measurement properties of the PHQ-15 and SSS-8.

Results

A total of 305 studies with 361 243 participants were included. Most concerned routine care (178 studies) and the general population (27 studies). In factor analyses, both scales reflected a combination of domain-specific factors (cardiopulmonary, fatigue, gastrointestinal, pain) and a general symptom burden factor. The pooled PHQ-15 α was 0.81 (95% CI, 0.80-0.82), but with low item-total correlations for items concerning menstrual problems, fainting spells, and sexual problems (item-total correlations <0.40), and the SSS-8 α was 0.80 (0.77-0.83). Pooled correlations with other measures of somatic symptom burden were 0.71 (95% CI, 0.64-0.78) for the PHQ-15 and 0.82 (95% CI, 0.72-0.92) for the SSS-8. Reported AUROCs for identification of somatoform disorders ranged from 0.63 (95% CI, 0.50-0.76) to 0.79 (95% CI, 0.73-0.85) for the PHQ-15 and from 0.71 (95% CI, 0.66-0.77) to 0.73 (95% CI, 0.69-0.76) for the SSS-8. The minimal clinically important difference on both scales was 3 points. Test-retest reliability could not be pooled and was inconsistent for the PHQ-15 (PHQ-15: r = 0.65-0.93; ICC, 0.87; SSS-8: r = 0.996, ICC = 0.89). The PHQ-15 showed tentative sensitivity to change (g = 0.32; 95% CI, 0.08-0.56), but data for the SSS-8 were lacking.

Conclusions and Relevance

In this systematic review and meta-analysis, findings supported use of the PHQ-15 and SSS-8 for the assessment of symptom burden, but users should be aware of the complex, multifactorial structures of these scales. More evidence is needed concerning longitudinal measurement properties.

The role of neuropsychology in the care of patients with functional neurological symptom disorder

OBJECTIVE

Functional neurological symptom disorder (FNSD) is a neuropsychiatric condition characterized by signs/symptoms associated with brain network dysfunction. FNSDs are common and are associated with high healthcare costs. FNSDs are relevant to neuropsychologists, as they frequently present with chronic neuropsychiatric symptoms, subjective cognitive concerns, and/or low neuropsychological test scores, with associated disability and reduced quality of life. However, neuropsychologists in some settings are not involved in care of patients with FNSDs. This review summarizes relevant FNSD literature with a focus on the role of neuropsychologists.

METHODS

A brief review of the literature is provided with respect to epidemiology, public health impact, symptomatology, pathophysiology, and treatment.

RESULTS

Two primary areas of focus for this review are the following: (1) increasing neuropsychologists' training in FNSDs, and (2) increasing neuropsychologists' role in assessment and treatment of FNSD patients.

CONCLUSIONS

Patients with FNSD would benefit from increased involvement of neuropsychologists in their care.

Reduced Subjective Cognitive Concerns With Neurobehavioral Therapy in Functional Seizures and Traumatic Brain Injury

OBJECTIVE

Functional seizures are common among people with traumatic brain injury (TBI). Subjective cognitive concerns refer to a person's own perception of problems with cognitive functioning in everyday life. The authors investigated the presence and correlates of subjective cognitive concerns and the response to neurobehavioral therapy among adults with TBI and functional seizures (TBI+FS group).

METHODS

In this observational study, participants in the TBI+FS group (N=47) completed a 12-session neurobehavioral therapy protocol for seizures, while participants in the comparison group (TBI without seizures) (N=50) received usual treatment. Subjective cognitive concerns, objective cognition, mental health, and quality of life were assessed before and after treatment. Data collection occurred from 2018 to 2022.

RESULTS

Baseline subjective cognitive concerns were reported for 37 (79%) participants in the TBI+FS group and 20 (40%) participants in the comparison group. In a multivariable regression model in the TBI+FS group, baseline global mental health (β=-0.97) and obsessive-compulsive symptoms (β=-1.01) were associated with subjective cognitive concerns at baseline. The TBI+FS group had fewer subjective cognitive concerns after treatment (η2=0.09), whereas the TBI comparison group showed a nonsignificant increase in subjective cognitive concerns.

CONCLUSIONS

Subjective cognitive concerns are common among people with TBI and functional seizures and may be related to general mental health and obsessive-compulsive symptoms. Evidence-based neurobehavioral therapy for functional seizures is a reasonable treatment option to address such concerns in this population, although additional studies in culturally diverse samples are needed. In addition, people with functional seizures would likely benefit from rehabilitation specifically targeted toward cognitive functioning.

Harnessing Placebo Effects for the Treatment of Functional Cognitive Disorder: A Feasibility Pilot Study

OBJECTIVE

Limited research has directly investigated whether and how placebo effects can be harnessed for the treatment of functional neurological disorder (FND), despite a long-standing and controversial history of interest in this area.

METHODS

A small exploratory study was conducted with adults with a cognitive subtype of FND recruited from a single cognitive neurology center in the United States. Participants were given the expectation of receiving cranial stimulation that could benefit their memory symptoms; however, the intervention was sham transcranial magnetic stimulation (placebo). Outcomes included measures of short-term memory testing, subjective memory rating, and state anxiety before and after stimulation. After the study, the true objective and rationale for investigating placebo effects were explained in a scripted debriefing session. Acceptability of the study design and qualitative feedback were collected. Institutional ethics approval and signed consent were obtained.

RESULTS

Three patients (female, N=2; male, N=1; average age=57 years) were recruited. Outcome data were analyzed descriptively at the patient level. Trends of improvement in subjective memory rating, but not objective cognitive test scores, and decreases in state anxiety were observed. After the debriefing session, all patients found the study design to be acceptable (ratings of 70%, 90%, and 100%), and two of the three patients believed that withholding mechanistic information about the intervention was needed to leverage placebo effects as treatment.

CONCLUSIONS

In the first study to prospectively investigate the feasibility of harnessing placebo effects for the treatment of FND, promising preliminary findings were obtained, and methods and resources for use in larger future studies are offered.

Neuropsychological evaluation of functional cognitive disorder: A narrative review

Objective: To critically review contemporary theoretical models, diagnostic approaches, clinical features, and assessment findings in Functional Cognitive Disorder (FCD), and make recommendations for neuropsychological evaluation of this condition. Method: Narrative review. Results: FCD is common in neuropsychological practice. It is characterized by cognitive symptoms that are not better explained by another medical or psychiatric disorder. The cognitive symptoms are associated with distress and/or limitations in daily functioning, but are potentially reversible with appropriate identification and treatment. Historically, a variety of diagnostic frameworks have attempted to capture this condition. A contemporary conceptualization of FCD positions it as a subtype of Functional Neurological Disorder, with shared and unique etiological factors. Patients with FCD tend to perform normally on neuropsychological testing or demonstrate relatively weak memory acquisition (e.g. list learning trials) in comparison to strong attention and delayed recall performance. Careful history-taking and behavioral observations are essential to support the diagnosis of FCD. Areas of ongoing controversy include operationalizing "internal inconsistencies" and the role of performance validity testing. Evidence for targeted interventions remains scarce. Conclusions: Neuropsychologists familiar with FCD can uniquely contribute to the care of patients with this condition by improving diagnostic clarity, richening case formulation, communicating effectively with referrers, and leading clinical management. Further research is needed to refine diagnosis, prognosis, and treatment.

Objective and subjective neurocognitive functioning in functional motor symptoms and functional seizures: preliminary findings

INTRODUCTION

This study aimed to provide a preliminary assessment of objective and subjective neurocognitive functioning in individuals with functional motor symptoms (FMS) and/or functional seizures (FS). We tested the hypotheses that the FMS/FS group would display poorer objective attentional and executive functioning, altered social cognition, and reduced metacognitive accuracy.

METHOD

Individuals with FMS/FS (n = 16) and healthy controls (HCs, n = 17) completed an abbreviated CANTAB battery, and measures of intellectual functioning, subjective cognitive complaints, performance validity, and comorbid symptoms. Subjective performance ratings were obtained to assess local metacognitive accuracy.

RESULTS

The groups were comparable in age (p = 0.45), sex (p = 0.62), IQ (p = 0.57), and performance validity (p-values = 0.10-0.91). We observed no impairment on any CANTAB test in this FMS/FS sample compared to HCs, although the FMS/FS group displayed shorter reaction times on the Emotional Bias task (anger) (p = 0.01, np2 = 0.20). The groups did not differ in subjective performance ratings (p-values 0.15). Whilst CANTAB attentional set-shifting performance (total trials/errors) correlated with subjective performance ratings in HCs (p-values<0.005, rs = -0.85), these correlations were non-significant in the FMS/FS sample (p-values = 0.10-0.13, rs-values = -0.46-0.50). The FMS/FS group reported more daily cognitive complaints than HCs (p = 0.006, g = 0.92), which were associated with subjective performance ratings on CANTAB sustained attention (p = 0.001, rs = -0.74) and working memory tests (p < 0.001, rs = -0.75), and with depression (p = 0.003, rs = 0.70), and somatoform (p = 0.003, rs = 0.70) and psychological dissociation (p-values<0.005, rs-values = 0.67-0.85).

CONCLUSIONS

These results suggest a discordance between objective and subjective neurocognitive functioning in this FMS/FS sample, reflecting intact test performance alongside poorer subjective cognitive functioning. Further investigation of neurocognitive functioning in FND subgroups is necessary.

Functional Cognitive Disorder: Diagnosis, Treatment, and Differentiation from Secondary Causes of Cognitive Difficulties

Functional cognitive disorder is an increasingly common cause of referral to the memory clinic. As a substantial source of disability, clinicians involved in the management of patients with cognitive complaints need to familiarize themselves with this important differential diagnosis. Our approach focuses on the identification of positive features of internal inconsistency (historical and clinical clues alongside patterns of performance) instead of an exclusionary approach. Although effective treatments are desperately needed, promising therapies include metacognitive retraining and cognitive-behavioral therapy modalities. Future research should focus on a better understanding of disease trajectories and outcomes as well as the development of evidence-based interventions.

Clinical signs in functional cognitive disorders: A systematic review and diagnostic meta-analysis

OBJECTIVE

Functional cognitive disorder (FCD) accounts for around a third of patients attending specialized memory clinics. It is also overrepresented in patients with other functional and somatic diagnoses. So far, no long-term diagnostic validity studies were conducted, and a positive diagnostic profile is yet to be identified. We aimed to review the literature on diagnostic signs and symptoms that allow for a discrimination between FCD and neurodegeneration.

METHODS

Systematic review of Ovid-Medline®, Embase and PsycINFO databases. Relevant clinical features were extracted including demographics, symptom history, comorbidities, language and interaction profiles and cognitive assessments. Studies with quantifiable diagnostic accuracy data were included in a diagnostic meta-analysis.

RESULTS

Thirty studies (N = 8602) were included. FCD patients were younger, more educated, and more likely to have a family history of older onset dementia, abrupt symptom onset, and higher rates of anxiety, depression and sleep disturbance. Promising language profiles include longer duration of spoken answer, elaborated examples of memory failures, ability to answer compound and personal questions, and demonstration of working memory during interaction. The pooled analysis of clinical accuracy of different signs revealed that attending alone and bringing a handwritten list of problems particularly increase the odds of a FCD diagnosis. Current evidence from neuropsychometric studies in FCD is scarce.

CONCLUSIONS

Our systematic review reinforces that positive signs contribute for an early differentiation between FCD and neurodegeneration in patients presenting with memory complaints. It is the first to attain quantitative value to clinical observations. These results will inform future diagnostic decision tools and intervention testing.

Towards a neural network hypothesis for functional cognitive disorders: an extension of the Overfitted Brain Hypothesis

Introduction: Whilst the empirical understanding of functional cognitive disorders (FCD) has advanced in recent years, theoretical and conceptual models have evolved more slowly. Existing frameworks for FCD are based on models of other functional neurological disorders or of metacognitive processes and are recognised to lack mechanistic precision.Methods: In this article, a novel application to FCD of Hoel's Overfitted Brain Hypothesis of the evolved function of dreaming is attempted.Results: This posits that the empirically observed sleep disturbance in FCD entails impaired dreaming which causes the brain to be overfitted and hence unable to generalise appropriately, producing mismatch between memory expectations and memory performance.Conclusions: This formulation of FCD is based on considerations derived from the study of neural networks and shares commonalities with Bayesian models of functional neurological disorders. Additionally, it has implications for future hypothesis-driven research in FCD and suggests a pragmatic basis for management strategies.