Inability to self-report pain after a stroke: a population-based study.

The frequency of not being able to self-report pain after a stroke has not been previously assessed in a population-based sample. We studied the epidemiology of this problem using a cohort of patients hospitalized after a stroke in Olmsted County, Minnesota, from June 1, 2008, to June 1, 2012. Overall, 52 of 388 (13.4%) individuals were unable to provide a meaningful response to either a Faces Pain Scale or Numerical Rating Scale on admission. Inability to self-report pain was associated with measures of stroke severity (P<.0001), aphasia severity (P<.0001), and level of consciousness (P<.0001). Inability to self-report pain on admission was further associated with either subsequent death during the hospitalization (P<.0001) or an inability to provide self-report on dismissal (P<.0001). Our study further defines the epidemiology of the inability to self-report pain after a stroke as being less common than previously thought. Attempts to validate observational pain scales for poststroke patients should focus on those individuals with aphasia and/or depressed levels of consciousness.