The frequency and prognostic significance of ‘new’ behavioural signs in patients with chronic impaired consciousness

One of the challenges encountered during the diagnostic assessment of patients with chronic disorders of consciousness (DOC) is determining the prognosis for a return to higher levels of consciousness. This situation has prompted new research aimed at identifying additional predictors of the outcome of DOC. This article describes cases in which patients in this group exhibited new behavioural signs (NBS), such as facial reaction to stimulation, subtle motor reactions, and crossing of the legs. The signs under consideration are not currently included in the diagnostic criteria of scales designed to assess the level of consciousness.

Objective: to determine the incidence of NBS in patients with DOC and its significance for the prognosis of recovery of consciousness.

Material and methods. The study included 44 patients with DOC (of traumatic and non-traumatic origin) who were admitted to the Intensive Care Unit (ICU) of the Brain Institute Clinic rehabilitation center between 2023 and 2025. The time elapsed since brain injury at the time of admission was 123.02±24.82 days. The Coma Recovery Scale – Revised (CRS-R) was used to assess the level of impaired consciousness.

Results. Analysis of the CRS-R scale data obtained from the study groups indicates that an improvement in the level of consciousness was observed in both groups. In the group of patients without NBS, the mean score on admission was 8.36±3.46; on discharge, it was 9.04±3.55. In the group of patients with NBS, the mean score on admission was 8.00±2.73, and at the end of hospitalisation – 11.06±3.54. The most common symptom was ‘Subtle motor reactions’ – 15 cases out of 22. In 10 patients, the second group of manifestations was recorded – ‘Facial reaction to stimulation’. The smallest group consisted of the sign ‘Crossing of the legs’ – recorded in two cases (only in combination with other signs). There were noticeable transitions to higher levels of consciousness in patients with recorded NBS – a state of minimal consciousness ‘plus’, as well as the subsequent return to clear consciousness in patients (the number of cases was three times higher than the number of similar recorded cases in the control group).

Conclusion. The high reproducibility of ‘new’ behavioural response patterns in patients with initially different levels of consciousness (unresponsive wakefulness syndrome, ‘minus’ minimal consciousness, and ‘plus’ minimal consciousness) suggests that these patterns may be considered as predictors of a positive recovery outcome.

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