Catatonia Rating Scales in Patients with Persistent Vegetative State

Abstract

Objective: Persistent vegetative state (PVS) has similar clinical presentations with catatonia. Both PVS and catatonia can be evaluated using clinical observation and rating scales. We intended to study how catatonia rating scales perform in assessing PVS patients as compared to the standard PVS scale. Methods: Thirty residents from two nursing homes for PVS patients were evaluated with Coma Recovery Scale-Revised (CRS-R) and two catatonia rating scales (Bush–Francis Catatonia Rating Scale [BFCRS] and KANNER scale). Ten residents recovering from PVS were selected as controls, and twenty residents still meeting the criteria of PVS were selected as PVS group. Three evaluations were assessed over 6 months. We compared and analyzed the scores of each visit. The components of BFCRS and KANNER scales were also analyzed to create a simpler version for PVS patients. Results: BFCRS and KANNER scales, as well as their simplified versions, had significant correlations with CRS-R (p < 0.001 for all). This could imply that catatonia rating scales could also be used in evaluating PVS patients. Upon closer examinations of scale components, all the three scales shared components such as consciousness levels and eye movements, but BFCRS and KANNER have evaluations on rigidity and negativism, which CRS-R does not had. Conclusion: Our data suggest that PVS and catatonia share an underlying pathological mechanism. Evaluations of muscle tension, an important component of catatonia rating scales, might offer a more thorough assessment of PVS patients. Further study of using catatonia rating scales in PVS patients is warranted.