Spasticity in Prolonged Disorders of Consciousness: A Prospective Cohort Study.

Background: Spasticity is a frequent and disabling complication in patients with prolonged disorders of consciousness (PDOC), yet its prevalence, distribution, evolution, and relationship with recovery of consciousness remain poorly characterized. The aim was to investigate the prevalence, severity, distribution, and evolution of spasticity in PDOC patients undergoing early intensive neurorehabilitation (EIN), and to explore clinical factors associated with spasticity and its relationship with level of consciousness (LOC). Methods: This study was embedded in the nationwide prospective DOCTOR cohort and included 126 PDOC patients admitted for EIN in the Netherlands between 2019 and 2023. Spasticity was assessed at admission and discharge using the Ashworth Scale (AS) across seven bilateral muscle groups. Associations between spasticity, demographic and clinical variables, medication use, nociception, and recovery of consciousness were analyzed. Results: Spasticity was highly prevalent at EIN admission (88%) and discharge (90%), with mostly bilateral and widespread involvement. Elbow flexors, wrist flexors, hip adductors, and knee flexors were most frequently affected. Severe spasticity was present in 19% at admission and 30% at discharge. Spasticity severity correlated positively with pain scores and use of spasmolytics, but not with LOC. No association was found between spasticity at admission and recovery of consciousness. Conclusions: Spasticity is nearly ubiquitous and often progressive in PDOC, even during specialized neurorehabilitation. Its evolution appears independent of recovery of consciousness, underscoring the need to assess and manage spasticity as a distinct clinical entity. Prospective interventional studies are warranted to optimize spasticity treatment in this population.