Neurophysiological predictors of full clinical consciousness recovery in patients with DoC: a retrospective evaluation of the DoC-NP Score.

BACKGROUND

Prognostication in prolonged disorders of consciousness (pDoC) remains challenging, particularly when estimating recovery of a clinically observable conscious state. Multimodal neurophysiological markers may provide complementary prognostic information beyond behavioral assessment alone.

OBJECTIVE

To develop and retrospectively evaluate a composite neurophysiological score (DoC-NP Score) for predicting emergence from the minimally conscious state (eMCS) during post-acute neurorehabilitation.

METHODS

This retrospective cohort study included 76 patients with pDoC following severe acquired brain injury (sABI). Clinical assessment using the Coma Recovery Scale-Revised (CRS-R) was performed at admission (T0) and discharge (T1). Neurophysiological evaluation at T0 included EEG, upper-limbs somatosensory evoked potentials (SEPs), and auditory event-related potentials (ERPs). The DoC-NP Score integrates standard EEG features (continuity, amplitude, dominant frequency and reactivity), N20 SEPs, and P300 ERPs into a composite ordinal score. Associations between the DoC-NP Score, eMCS recovery, and functional outcomes (LCF, DRS) were analyzed using regression models and ROC analysis.

RESULTS

Higher DoC-NP scores at T0 were associated with greater likelihood of eMCS at T1 (OR = 1.768 per point; AUC = 0.768, optimal cut-off = 6) and independently predicted better functional (LCF, p < 0.005) and disability (DRS, p < 0.025) outcomes. eMCS was achieved at T1 by 35 patients (46%), independent of injury etiology (p > 0.05). EEG AFR (r = 0.854), EEG continuity (r = 0.668) and SEPs (r = 0.673) contributed most to the prognostic value of the composite score, while ERPs showed moderate (r = 0.489). Moreover, the DoC-NP score correlates moderately with the change in CRS-R total score (r = 0.434, p < 0.001), auditory function (r = 0.445, p < 0.001), motor function (r = 0.435, p < 0.001), motor oral/verbal function (r = 0.334, p = 0.003), communication (r = 0.315, p = 0.003); poorly with visual function (r = 0.27, p = 0.016) and no correlation with vigilance (p = 0.168).

CONCLUSIONS

The DoC-NP Score is a feasible multiparametric neurophysiological tool that may support prognostic stratification in pDoC patients as a complementary component to multimodal assessment, although its modest incremental predictive value requires prospective validation.