Prospective Study of Different Diagnostic Criteria for Catatonia and Delirium in Internal Medicine and Neurology Admissions.

OBJECTIVE

The authors prospectively examined the relationship between catatonia and delirium in consecutive hospital admissions. Potentially confounding neuropsychiatric conditions for catatonia symptoms were also assessed.

METHODS

In this cross-sectional study of 223 geriatric inpatients with or without delirium, the authors rated symptoms with Bush-Francis Catatonia Rating Scale (BFCRS) items to diagnose catatonia according to the BFCRS, DSM-5-TR, and Research Diagnostic Criteria for Catatonia (RDCC). The Delirium Rating Scale-Revised-98 (DRS-R-98) and other tools were used to assess neuropsychiatric conditions. The BFCRS item relationships were analyzed with exploratory factor analysis (EFA) and correlation analyses.

RESULTS

Catatonia prevalence in the patient cohort was 10% and 1% per BFCRS and DSM-5-TR criteria, respectively, and significantly higher in the delirium group; no patient had catatonia per the RDCC. EFA identified three BFCRS factors, with immobility/stupor, mutism, and staring loading together onto the first factor. However, EFA explained only 48% of the variance, possibly attributable to catatonia symptom overlap with other conditions. EFA supported akinesia as a core catatonia feature. Many correlations between BFCRS items and scores for apathy, parkinsonism, dementia, depression, neuroleptic use, and drowsiness suggested confounding. Few correlations were observed between BFCRS and DRS-R-98 items, notably excitement with psychosis and motor agitation, as well as mitgehen with items representing the three core delirium domains and psychosis.

CONCLUSIONS

Comorbidity of catatonia with delirium was rare or absent when using DSM-5-TR criteria or the RDCC. The BFCRS criteria yielded a 10% catatonia rate, but BFCRS items were confounded by other conditions. Rigorous differential diagnosis of catatonia is needed among geriatric patients.