title: The Impact of Spinal Cord Stimulation on Sleep Patterns.
abstract: BACKGROUND
  Studies of chronic pain show sleep disturbances to be a prevalent symptom in 50-88% of patients and studies show improved pain to correspond with improved sleep. The impact of spinal cord stimulation (SCS) on sleep in failed back surgery syndrome, complex regional pain syndrome, and neuropathic pain patients has not been studied prospectively.
  
  
  OBJECTIVE
  We prospectively assess the impact of SCS on sleep quality using the Insomnia Severity Index (ISI) and Epworth Sleepiness Scale (ESS). Further we examine the correlations between sleep and pain.
  
  
  METHODS
  Patients who underwent permanent SCS implantation completed six validated questionnaires to compare sleep patterns, pain intensity, and quality of life at baseline and six months postoperatively. Results were analyzed via paired samples t-tests and bivariate analysis.
  
  
  RESULTS
  Data from 27 patients were collected. We saw a significant decrease in ISI scores (n = 23, t(df)=2.9(22), p = 0.008), and noted a trend in the percentage improvement between ISI and ESS (n = 12, t(df)=2.0(10), p = 0.078). We did not see any significant improvement in ESS. However, improvements in insomnia correlated with pain intensity as measured through visual analog scale score and McGill Pain Questionnaire (R = 0.546, p = 0.007 and R = 0.559, p = 0.006, respectively).
  
  
  CONCLUSIONS
  We demonstrate that insomnia scores on ISI improve with SCS at six-month follow-up. Further, we find that improvements in pain correlate with these ISI improvements.
authors: Department of Neurosurgery, Albany Medical College, Albany, NY, USA.
authors: Tina
authors: T
authors: Ramineni
authors: Department of Neurosurgery, Albany Medical College, Albany, NY, USA.|Department of Neurology, Albany Medical College, Albany, NY, USA.
authors: Julia
authors: J
authors: Prusik
authors: Department of Neurosurgery, Albany Medical College, Albany, NY, USA.
authors: Samik
authors: S
authors: Patel
authors: Department of Neurosurgery, Albany Medical College, Albany, NY, USA.
authors: Steven
authors: S
authors: Lange
authors: Department of Neurosurgery, Albany Medical College, Albany, NY, USA.
authors: Jessica
authors: J
authors: Haller
authors: Department of Neurosurgery, Albany Medical College, Albany, NY, USA.
authors: Chris
authors: C
authors: Fama
authors: Department of Neurology, Albany Medical College, Albany, NY, USA.
authors: Charles
authors: C
authors: Argoff
authors: Department of Neurosurgery, Albany Medical College, Albany, NY, USA.|Center for Neuroscience and Neuropharmacology, Albany Medical College, Albany, NY, USA.
authors: Julie
authors: J
authors: Pilitsis
mesh_terms: D000328:Adult; D000368:Aged; D059350:Chronic Pain / Q000150:complications* / Q000628:therapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D010147:Pain Measurement; D012720:Severity of Illness Index; D012893:Sleep Wake Disorders / Q000209:etiology* / Q000628:therapy*; D062187:Spinal Cord Stimulation / Q000379:methods*; D013223:Statistics as Topic; D064232:Visual Analog Scale
keywords: ESS; ISS; VAS; sleep; spinal cord stimulation