Original research| Volume 101, ISSUE 1, P95-105, January 2020

Effect of Rehabilitation Treatments on Disability in Persons With Disorders of Consciousness: A Propensity Score Study

Published:August 26, 2019DOI:


      • Rehabilitation (physical and cognitive) reduced the clinical worsening over time.
      • The difference between the groups that received treatment vs those that did not receive treatment was approximately 6.5 Disability Rating Scale points.
      • Cognitive rehabilitation was administered to patients who were less clinically impaired.



      To evaluate the effects of rehabilitation (physical and cognitive) treatments on the diagnosis severity and Disability Rating Scale (DRS) scores, adjusted for a number of potential confounders measured at baseline, in a large cohort of patients with disorders of consciousness across time.

      Design and Setting

      An observational, longitudinal (2 evaluations), multicenter project was made in 90 Italian centers.


      Patients (N=364) with a diagnosis of disorders of consciousness.

      Main Outcome Measures

      Primary outcome was the severity of diagnosis, expressed on an ordinal scale (Other<MCS<VS<death). In the Other group were included patients who emerged from an MCS and recovered consciousness. The secondary outcome was the DRS score (range of 0-30 with 30 being the worst value). The DRS is a tool used to define the level of residual disability, commonly used to classify the level of functional impairment in patients with acquired brain injury. Both outcomes were measured for each wave.


      A total of 364 subjects having a complete set of demographic, clinical, and pharmacologic data were included in the propensity score (PS) analysis. Results showed that the rehabilitation treatments (physical and cognitive) reduced the clinical worsening over time in both severity diagnosis and DRS (around 6.5 points) in patients with disorders of consciousness across different propensity score strategies (ie, PS matching, PS adjustment, and PS-weighted procedures). In addition, cognitive protocols seem to be limited to patients with a median value of DRS=23.


      Our propensity score analysis suggests that rehabilitation treatment protocols seem effective and should be applied to a broader spectrum of patients with disorders of consciousness.


      List of abbreviations:

      CI (confidence interval), DOC (disorder of consciousness), DRS (Disability Rating Scale), IPTW (inverse probability of treatment weighting), IQR (interquartile range), MCS (minimally conscious state), OP (only physical), PPC (physical plus cognitive), PS (propensity score), VS (vegetative state)
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