Catatonia: demographic, clinical and laboratory associations

First 150 years of catatonia: Looking back at its complicated history and forward to the road ahead

Karl Ludwig Kahlbaum (1828-1899) was the first to conceptualize and describe the main clinical features of a novel psychiatric illness, which he termed catatonia in his groundbreaking monograph published 150 years ago. Although Kahlbaum postulated catatonia as a separate disease entity characterized by psychomotor symptoms and a cyclical course, a close examination of his 26 cases reveals that most of them presented with motor symptom complexes or syndromes associated with various psychiatric and medical conditions. In his classification system, Kraepelin categorized catatonic motor symptoms that occur in combination with psychotic symptoms and typically have a poor prognosis within his dementia praecox (schizophrenia) disease entity. Because of the substantial influence of Kraepelin's classification, catatonia was predominantly perceived as a component of schizophrenia for most of the 20th century. However, with the advent of the psychopharmacotherapy era starting from the early 1950s, interest in catatonia in both clinical practice and research subsided until the early 2000s. The past two decades have witnessed a resurgence of interest in catatonia. The Diagnostic and Statistical Manual of Mental Disorders Fifth Edition, marked a paradigmatic shift by acknowledging that catatonia can occur secondary to various psychiatric and medical conditions. The introduction of an independent diagnostic category termed "Catatonia Not Otherwise Specified" significantly stimulated research in this field. The authors briefly review the history and findings of recent catatonia research and highlight promising directions for future exploration.

Diagnostic features of paediatric catatonia: multisite retrospective cohort study

BACKGROUND

Catatonia is a neuropsychiatric disorder characterised by psychomotor changes that can affect individuals across the lifespan. Although features of catatonia have been described in adults, the most common clinical symptoms among paediatric patients with catatonia are not well characterised.

AIMS

The goal of this study was to characterise the symptoms of catatonia demonstrated by paediatric patients, and to explore demographic and diagnostic factors associated with greater catatonia severity.

METHOD

We conducted a multicentre retrospective cohort study, from 1 January 2018 to 6 January 2023, of patients aged 18 and younger with a clinical diagnosis of catatonia and symptom assessment using the Bush Francis Catatonia Rating Scale (BFCRS).

RESULTS

A total of 143 patients met inclusion criteria. The median age was 15 (interquartile range: 13-16) years and 66 (46.2%) patients were female. Neurodevelopmental disabilities were present in 55 (38.5%) patients. Patients demonstrated a mean of 6.0 ± 2.1 signs of catatonia on the Bush Francis Catatonia Screening Item, with a mean BFCRS score of 15.0 ± 5.9. Among the 23 items of the BFCRS, six were present in >50% of patients (staring, mutism, immobility/stupor, withdrawal, posturing/catalepsy, rigidity), and four were present in <20% of cases (waxy flexibility, mitgehen, gegenhalten, grasp reflex). In an adjusted model, patients with neurodevelopmental disorders demonstrated greater BFCRS severity than those with other diagnoses.

CONCLUSIONS

Catatonia was diagnosed in a range of mental health conditions. Further research is needed to define optimal diagnostic criteria for catatonia in paediatric patients, and clarify the clinical course of the disorder.

Case report: Psychosis with catatonia in an adult man: a presentation of neurosarcoidosis

Introduction

Sarcoidosis is a multisystem non-caseous granulomatous disease of unknown origin with predominant lung involvement and a variable clinical course. Although rare, neuropsychiatric manifestations such as confusion, problems in orientation, memory dysfunction, delusions, hallucinations and catatonia can be presenting features of sarcoidosis with nervous system involvement, also known as neurosarcoidosis.

Case description

We present a 39-year-old man with acute-onset vertigo, balance problems and confusion quickly developing delusions, hallucinations, catatonic symptoms and suicidal behaviour. Symptoms appeared to be a manifestation of neurosarcoidosis.

Diagnostic assessment

The differential diagnosis of psychosis is broad and should include pertinent auto-immune disorders, paraneoplastic, oncologic, metabolic, and neurodegenerative disorders. Basic systemic screening should include blood and urinary tests, a chest X-ray, brain CT scan and ECG. If neurosarcoidosis is suspected, an MRI of the brain with contrast and lumbar puncture are most appropriate. Multidisciplinary collaboration is essential to arrive at a correct diagnosis and effective management of the patient.

Discussion

Despite the large number of sarcoidosis and psychosis studies, the etiology and pathogenesis of both illnesses remain incompletely understood. A common inflammatory etiopathological pathway has been postulated.

Conclusions

Clinicians should consider organic causes when confronted with a middle-aged patient experiencing a first psychotic episode with an atypical onset, catatonic features, or dysfunction in orientation and/or memory, a complete lack of a positive familial psychiatric history and/or an atypical response to (psycho)pharmacological treatment.

Structural alterations of the motor cortex and higher order cortical areas suggest early neurodevelopmental origin of catatonia in schizophrenia

The neurobiology of catatonia is still poorly understood. Particularly structural MRI studies yielded conflicting results. Heterogeneity of findings was suggested to stem from specifics of different rating scales. This study sought to test grey matter differences between patients with catatonia, patients without catatonia, and healthy controls using the two main instruments of catatonia rating. We included 98 patients with schizophrenia spectrum disorders and 42 healthy controls. Catatonia was measured using the Bush Francis Catatonia Rating Scale and the Northoff Catatonia Rating Scale. According to these scales, patients were classified into those with and those without catatonia. We tested whole brain grey matter volume, cortical thickness, and local gyrification across groups. Both catatonia rating scales correlated at tau = 0.65 but failed to classify identical subjects as catatonia patients. However, group differences in grey matter parameters were broadly similar with either rating scale to identify catatonia cases. Catatonia patients had reduced grey matter volume compared to controls in a large network including orbitofrontal cortex, cingulate, thalamus, and amygdala. While there was no group difference in cortical thickness, catatonia patients had increased local gyrification in premotor, motor, and parietal cortices compared to controls. Hypergyrification of the motor cortex and higher order cortical areas was found in catatonia patients compared to patients without catatonia. Both catatonia rating scales find similar symptom severity and group differences in grey matter indices. Catatonia is linked to reduced grey matter volume and increased local gyrification, suggesting some impact of early neurodevelopmental insults.

The origins of catatonia - Systematic review of historical texts between 1800 and 1900

Since January 1st 2022, catatonia is (again) recognized as an independent diagnostic entity in the 11th revision of the International Classification of Diseases (ICD-11). This is a relevant time to systematically review how the concept of catatonia has evolved within the 19th century and how this concept changed under the influence of a wide variety of events in the history of psychiatry. Here, we systematically reviewed historical and modern German and English texts focusing on catatonic phenomena, published from 1800 to 1900. We searched five different electronical databases (https://archive.org, www.hathitrust.org, www.books.google.de, https://link.springer.com and PubMed) and closely reviewed 60 historical texts on catatonic symptoms. Three main findings emerged: First, catatonic phenomena and their underlying mechanisms were studied decades before Karl Ludwig Kahlbaum's catatonia concept of 1874. Second, Kahlbaum not only introduced catatonia, but, more generally, also called for a new classification of psychiatric disorders based on a comprehensive analysis of the entire clinical picture, including the dynamic course and cross-sectional symptomatology. Third, the literature review shows that between 1800 and 1900 catatonic phenomena were viewed to be 'located' right at the interface of motor and psychological symptoms with the respective pathophysiological mechanisms being discussed. In conclusion, catatonia can truly be considered one of the most exciting and controversial entity in both past and present psychiatry and neurology, as it occupies a unique position in the border territory between organic, psychotic and psychogenic illnesses.

The diagnosis and treatment of catatonia

Catatonia is a severe neuropsychiatric syndrome that affects emotion, speech, movement and complex behaviour. It can occur in a wide range of psychiatric and neurological conditions, including depression, mania, schizophrenia, autism, autoimmune encephalitis (particularly NMDAR encephalitis), systemic lupus erythematosus, thyroid disease, epilepsy and medication-induced and -withdrawal states. This concise guideline highlights key recommendations from the British Association for Psychopharmacology (BAP) Catatonia Guideline, published in April 2023. Important investigations may include neuroimaging, electroencephalography and assessment for neuronal autoantibodies in serum and cerebrospinal fluid. First-line treatment comprises benzodiazepines and/or electroconvulsive therapy. The benzodiazepine of choice is lorazepam, which is sometimes used in very high doses. Multidisciplinary working between psychiatrists and physicians is often essential. The main limitation of the guidelines is the low quality of the underlying evidence, comprising mainly small observational studies and case reports or series.

The role of the electroencephalogram (EEG) in determining the aetiology of catatonia: a systematic review and meta-analysis of diagnostic test accuracy

BACKGROUND

Catatonia is a psychomotor syndrome that has a wide range of aetiologies. Determining whether catatonia is due to a medical or psychiatric cause is important for directing treatment but is clinically challenging. We aimed to ascertain the performance of the electroencephalogram (EEG) in determining whether catatonia has a medical or psychiatric cause, conventionally defined.

METHODS

In this systematic review and meta-analysis of diagnostic test accuracy (PROSPERO CRD42021239027), Medline, EMBASE, PsycInfo, and AMED were searched from inception to May 11, 2022 for articles published in peer-reviewed journals that reported EEG findings in catatonia of a medical or psychiatric origin and were reported in English, French, or Italian. Eligible study types were clinical trials, cohort studies, case-control studies, cross-sectional studies, case series, and case reports. The reference standard was the final clinical diagnosis. Data extraction was conducted using individual patient-level data, where available, by two authors. We prespecified two types of studies to overcome the limitations anticipated in the data: larger studies (n ≥ 5), which were suitable for formal meta-analytic methods but generally lacked detailed information about participants, and smaller studies (n < 5), which were unsuitable for formal meta-analytic methods but had detailed individual patient level data, enabling additional sensitivity analyses. Risk of bias and applicability were assessed with the QUADAS-2 tool for larger studies, and with a published tool designed for case reports and series for smaller studies. The primary outcomes were sensitivity and specificity, which were derived using a bivariate mixed-effects regression model.

FINDINGS

355 studies were included, spanning 707 patients. Of the 12 larger studies (5 cohort studies and 7 case series), 308 patients were included with a mean age of 48.2 (SD = 8.9) years. 85 (52.8%) were reported as male and 99 had catatonia due to a general medical condition. In the larger studies, we found that an abnormal EEG predicted a medical cause of catatonia with a sensitivity of 0.82 (95% CI 0.67-0.91) and a specificity of 0.66 (95% CI 0.45-0.82) with an I ² of 74% (95% CI 42-100%). The area under the summary ROC curve offered excellent discrimination (AUC = 0.83). The positive likelihood ratio was 2.4 (95% CI 1.4-4.1) and the negative likelihood ratio was 0.28 (95% CI 0.15-0.51). Only 5 studies had low concerns in terms of risk of bias and applicability, but a sensitivity analysis limited to these studies was similar to the main analysis. Among the 343 smaller studies, 399 patients were included, resulting in a sensitivity of 0.76 (95% CI 0.71-0.81), specificity of 0.67 (0.57-0.76) and AUC = 0.71 (95% CI 0.67-0.76). In multiple sensitivity analyses, the results were robust to the exclusion of reports of studies and individuals considered at high risk of bias. Features of limbic encephalitis, epileptiform discharges, focal abnormality, or status epilepticus were highly specific to medical catatonia, but features of encephalopathy had only moderate specificity and occurred in 23% of the cases of psychiatric catatonia in smaller studies.

INTERPRETATION

In cases of diagnostic uncertainty, the EEG should be used alongside other investigations to ascertain whether the underlying cause of catatonia is medical. The main limitation of this review is the differing thresholds for considering an EEG abnormal between studies.

FUNDING

Wellcome Trust, NIHR Biomedical Research Centre at University College London Hospitals NHS Foundation Trust.

Catatonia Due to General Medical Conditions in Psychiatric Patients: Implications for Clinical Practice

Catatonic syndrome is frequently observed over the course of severe mental disorders and general medical conditions, but when catatonia occurs in psychiatric patients with co-morbid medical or neurologic conditions, diagnosis and management may be challenging. Several medical conditions may cause catatonia in psychiatric patients, but some, such as brain injury, infections, hyponatremia and critical illness, may be most relevant in this population. Alongside appropriate etiologic treatment, benzodiazepines and electroconvulsive therapy in refractory cases are effective and safe, and may resolve catatonic syndrome rapidly. When newly-onset psychotic symptoms in catatonic patients with established psychotic disorders occur, delirium should be suspected and appropriately managed. An extensive clinical and laboratory diagnostic workup to determine the underlying etiology of catatonic syndrome should be carried out. In cases of acute multi-morbidity, the exact cause of catatonic syndrome in psychiatric patients may be unclear. It is recommended to avoid antipsychotic drugs in acutely catatonic patients, because they may exacerbate the catatonic symptoms. The akinetic type of catatonia should be differentiated from hypoactive delirium, as treatments for these syndromes differ substantially. When a psychiatric patient presents with symptomatology of both catatonia and delirium, treatment is particularly challenging.

[Catatonia Through the Ages - from Kahlbaum to the ICD-11]

For decades, the psychomotor syndrome of catatonia was considered exclusively a subtype of schizophrenia. The use of antipsychotics and changes in the teaching content in the further training of psychiatrists led to the fact that catatonia was hardly recognized anymore. Yet catatonia is in principle well treatable. The new status in ICD-11 will probably allow to better teach, recognize, and treat catatonia in the future.

A survey on clinical natural language processing in the United Kingdom from 2007 to 2022

Much of the knowledge and information needed for enabling high-quality clinical research is stored in free-text format. Natural language processing (NLP) has been used to extract information from these sources at scale for several decades. This paper aims to present a comprehensive review of clinical NLP for the past 15 years in the UK to identify the community, depict its evolution, analyse methodologies and applications, and identify the main barriers. We collect a dataset of clinical NLP projects (n = 94; £ = 41.97 m) funded by UK funders or the European Union's funding programmes. Additionally, we extract details on 9 funders, 137 organisations, 139 persons and 431 research papers. Networks are created from timestamped data interlinking all entities, and network analysis is subsequently applied to generate insights. 431 publications are identified as part of a literature review, of which 107 are eligible for final analysis. Results show, not surprisingly, clinical NLP in the UK has increased substantially in the last 15 years: the total budget in the period of 2019-2022 was 80 times that of 2007-2010. However, the effort is required to deepen areas such as disease (sub-)phenotyping and broaden application domains. There is also a need to improve links between academia and industry and enable deployments in real-world settings for the realisation of clinical NLP's great potential in care delivery. The major barriers include research and development access to hospital data, lack of capable computational resources in the right places, the scarcity of labelled data and barriers to sharing of pretrained models.

Clinical Neuroimaging Findings in Catatonia: Neuroradiological Reports of MRI Scans of Psychiatric Inpatients With and Without Catatonia

OBJECTIVE

Catatonia is a debilitating psychomotor disorder. Previous neuroimaging studies have used small samples with inconsistent results. The authors aimed to describe the structural neuroradiological abnormalities in clinical magnetic resonance imaging (MRI) brain scans of patients with catatonia, comparing them with scans of psychiatric inpatients without catatonia. They report the largest study of catatonia neuroimaging to date.

METHODS

In this retrospective case-control study, neuroradiological reports of psychiatric inpatients who had undergone MRI brain scans for clinical reasons were examined. Abnormalities were classified by lateralization, localization, and pathology. The primary analysis was prediction of catatonia by presence of an abnormal MRI scan, adjusted for age, sex, Black race-ethnicity, and psychiatric diagnosis.

RESULTS

Scan reports from 79 patients with catatonia and 711 other psychiatric inpatients were obtained. Mean age was 36.4 (SD=17.3) for the cases and 44.5 (SD=19.9) for the comparison group. Radiological abnormalities were reported in 27 of 79 cases (34.2%) and in 338 of 711 in the comparison group (47.5%) (odds ratio [OR]=0.57, 95% confidence interval [CI]=0.35, 0.93; adjusted OR=1.11, 95% CI=0.58, 2.14). Among the cases, most abnormal scans had bilateral abnormalities (N=23, 29.1%) and involved the forebrain (N=25, 31.6%) and atrophy (N=17, 21.5%).

CONCLUSIONS

Patients with catatonia were commonly reported to have brain MRI abnormalities, which largely consisted of diffuse cerebral atrophy rather than focal lesions. No evidence was found that these abnormalities were more common than in other psychiatric inpatients undergoing neuroimaging, after adjustment for demographic variables. Study limitations included a heterogeneous control group and selection bias in requesting scans.

Management and outcomes of catatonia: A prospective study in urban South Africa

Objectives:

Rapid intervention for catatonia with benzodiazepines and electroconvulsive therapy can prevent fatal complications. We describe the management and treatment response of 44 patients with catatonia in a psychiatric unit in urban South Africa. The objective was to screen admissions for catatonia and investigate management, treatment response, and treatment outcomes.

Method:

We used a prospective, descriptive, observational study design and collected data using a data collection sheet, the Bush Francis Catatonia Screening Instrument, the Bush Francis Catatonia Rating Scale, and the Diagnostic Statistical Manual-5 to assess catatonia in new admissions from September 2020 to August 2021.

Results:

Of the 241 participants screened on admission, 44 (18.3% of 241) screened positive for catatonia on the Bush Francis Catatonia Screening Instrument, while 197 (81.7% of 241) did not. Thirty-eight (86.4% of 44) received lorazepam, seven (15.9%) received clonazepam, and two (4.6%) received diazepam, implying that three (6.8%) of the 44 participants with catatonia received more than one benzodiazepine sequentially. Ten (22.7% of 44) patients received electroconvulsive therapy. Seven of those treated with electroconvulsive therapy (15.9% of 44 and 70% of 10) responded well and were discharged, whereas 22 (50% of 44 and 64.7% of 34) of those given lorazepam were discharged. Patients treated with electroconvulsive therapy had a higher initial Bush Francis Catatonia Rating Scale score. One patient (2.3%) relapsed within 4 weeks of discharge. Twenty (45.5%) of the 44 patients with catatonia had low average iron levels, 14 (31.8%) had low vitamin B12, and 24 (54.6%) had high creatinine kinase.

Conclusion:

Both lorazepam and electroconvulsive therapy were found to be effective treatments for catatonia with good response and outcomes. The length of hospital stay of patients with catatonia was similar to that of patients without catatonia. Treatment guidelines for catatonia need to include the role and timing of electroconvulsive therapy to augment current treatment protocols for the use of lorazepam.

A prospective descriptive study on prevalence of catatonia and correlates in an acute mental health unit in Nelson Mandela Bay, South Africa

Catatonia is a psychomotor abnormality caused by neurological, medical or severe psychiatric disorders and substances. Its prevalence ranges from less than 10% to just above 60%. Diagnosis may be influenced by the screening tools used. Screening of new admissions to a mental health unit for catatonia was undertaken using three instruments to determine prevalence of catatonia. Participants ranged from age 16 years and over. Recruitment took place from September 2020 to August 2021. The setting was a mental health unit within a general hospital in Nelson Mandela Metro, South Africa. Five assessors were trained by the principal investigator to apply the Bush Francis Screening Instrument (BFCSI), the Bush Francis Catatonia Rating Scale (BFCRS), and the Diagnostic and Statistical Manual 5 (DSM-5), to assess participants. Clinical and demographic data were collected using a specially designed datasheet. Data analysis was performed to identify significant associations between presence or absence of catatonia and clinical and demographic data. Up to 241 participants were screened and 44 (18.3%) had catatonia. All 44 cases were identified through the BFCSI while the DSM-5 identified only 16 (6.6%%) of the 44 cases even though the remaining 28 (63.6%) participants still required treatment for catatonic symptoms. The DSM-5 diagnostic criteria excluded staring, which was the commonest sign of catatonia identified through the BFCSI [n = 33 (75%)]. Close to half (21; 47.7%) of those with catatonia on the BFCSI had schizophrenia. The rest had bipolar disorder (12; 27.3%), substance-induced psychotic disorder (7; 15.9%) and no specified diagnosis in one (1; 2.6%). The BFCSI was very effective at identifying catatonia while the DSM-5 was inadequate, missing close to 64% (28 of 44) of cases. Predictors of catatonia in this sample were a younger age and being male. A prevalence of 18.3%, indicates that assessment for catatonia should be routinely conducted in this and similar settings.

Measuring catatonia motor behavior with objective instrumentation

OBJECTIVE

Catatonia is a neuropsychiatric syndrome, with important psychomotor features, associated with schizophrenia and other psychiatric disorders. The syndrome comprises multiple symptoms including abnormal motor control, behaviors, volition, and autonomic regulation. Catatonia assessment relies on clinical rating scales and clinicians familiar with the catatonia exam. However, objective instrumentation may aid the detection of catatonia. We aimed to investigate the relationship between movement parameters derived from actigraphy and expert ratings of catatonia symptoms measured by the Bush Francis Catatonia Rating Scale (BFCRS) and the Northoff Catatonia scale (NCS).

METHODS

Eighty-six acutely ill inpatients with schizophrenia spectrum disorders were assessed with the BFCRS, the NCS, and 24 h continuous actigraphy. Non-wear and sleep periods were removed from the actigraphy data prior to analysis. Associations between total catatonia scores, derived from both BFCRS and NCS, and actigraphy parameters as well as between single BFCRS items and actigraphy parameters were calculated using Spearman's rank correlation and non-parametric ANCOVAs (Quade's ANCOVAs), respectively.

RESULTS

Both higher BFCRS total scores (r = 0.369, p = 0.006) and NCS total scores (r = 0.384, p = 0.004) were associated with lower activity levels (AL). Higher scores on single BFCRS items such as immobility/stupor or staring were linked to lower AL (immobility/stupor: F = 17.388, p < 0.001, η² = 0.175; staring: F = 7.849, p = 0.001, η² = 0.162) and lower metabolic equivalents of task (MET).

CONCLUSION

Specific catatonia symptoms such as immobility/stupor and staring can be measured with actigraphy. This may aid the detection, staging, and monitoring of catatonia in clinical settings.

Catatonic Episodes Related to Substance Use: A Cross-Sectional Study Using Electronic Healthcare Records

Objective: Substance use has increasingly been linked to the onset of catatonic episodes; however, no large observational studies have examined this association. This study aimed to identify catatonic episodes temporally associated with acute intoxication, withdrawal or chronic substance use, investigate which substances were involved, and compare clinical characteristics of substance-related and non-substance-related catatonic episodes. Methods: This study retrospectively identified all catatonic episodes recorded in an electronic case register hosted at a large secondary mental health trust in London, UK. Episodes were categorized as substance-related if the clinical record reported either a positive urine drug screen, an ICD-10 diagnosis of a mental or behavioral disorder due to substance use, or documented substance use between two weeks prior to the catatonic episode and the date of the catatonic episode. Results: 108 of 2130 catatonic episodes (5.1%) were deemed substance-related. The number of contemporaneously reported substance-related episodes increased between 2007 and 2016 [r = 0.72, p = 0.02]. Episodes in the context of acute intoxication (n = 54) were most frequently related to cannabis (n = 31) or cocaine (n = 5) use, whilst those in the context of drug withdrawal (n = 8) were most commonly related to alcohol, opioids and benzodiazepines. There were 50 episodes of catatonia associated with chronic substance use without intoxication or withdrawal, of which the majority were related to cannabis use (n = 37). 21 episodes had overlapping intoxication, withdrawal and chronic use of different substances within an episode. Compared to catatonic episodes not related to substance use, episodes of substance-related catatonia occurred in individuals who were younger (mean age 31.3 years [SD 12.2] vs 35.7 years [SD 16.3], p = 0.01) and more likely to be men (74.0% vs 54.3%, p < 0.001). The clinical features of catatonia were similar between the two groups. Conclusions: A relatively small proportion of catatonic episodes were temporally associated with reported substance use within their electronic records. Substance-related catatonic episodes were mostly related to cannabis use, but other substances including cocaine, alcohol, opioids and benzodiazepines were sometimes implicated. This is likely an underestimate of substance-related catatonia use due to issues with documentation and appropriate investigation.

Catatonia Psychopathology and Phenomenology in a Large Dataset

BACKGROUND

The external clinical manifestations (psychopathology) and internal subjective experience (phenomenology) of catatonia are of clinical importance but have received little attention. This study aimed to use a large dataset to describe the clinical signs of catatonia; to assess whether these signs are associated with underlying diagnosis and prognosis; and to describe the phenomenology of catatonia, particularly with reference to fear.

METHODS

A retrospective descriptive cross-sectional study was conducted using the electronic healthcare records of a large secondary mental health trust in London, United Kingdom. Patients with catatonia were identified in a previous study by screening records using natural language processing followed by manual validation. The presence of items of the Bush-Francis Catatonia Screening Instrument was coded by the investigators. The presence of psychomotor alternation was assessed by examining the frequency of stupor and excitement in the same episode. A cluster analysis and principal component analysis were conducted on catatonic signs. Principal components were tested for their associations with demographic and clinical variables. Where text was available on the phenomenology of catatonia, this was coded by two authors in an iterative process to develop a classification of the subjective experience of catatonia.

RESULTS

Searching healthcare records provided 1,456 validated diagnoses of catatonia across a wide range of demographic groups, diagnoses and treatment settings. The median number of catatonic signs was 3 (IQR 2-5) and the most commonly reported signs were mutism, immobility/stupor and withdrawal. Stupor was present in 925 patients, of whom 105 (11.4%) also exhibited excitement. Out of 196 patients with excitement, 105 (53.6%) also had immobility/stupor. Cluster analysis produced two clusters consisting of negative and positive clinical features. From principal component analysis, three components were derived, which may be termed parakinetic, hypokinetic and withdrawal. The parakinetic component was associated with women, neurodevelopmental disorders and longer admission duration; the hypokinetic component was associated with catatonia relapse; the withdrawal component was associated with men and mood disorders. 68 patients had phenomenological data, including 49 contemporaneous and 24 retrospective accounts. 35% of these expressed fear, but a majority (72%) gave a meaningful narrative explanation for the catatonia, which consisted of hallucinations, delusions of several different types and apparently non-psychotic rationales.

CONCLUSION

The clinical signs of catatonia can be considered as parakinetic, hypokinetic and withdrawal components. These components are associated with diagnostic and prognostic variables. Fear appears in a large minority of patients with catatonia, but narrative explanations are varied and possibly more common.