title: Impact of kidney transplantation on sleep apnoea in patients with end-stage renal disease.
abstract: BACKGROUND
  Sleep apnoea is common in patients with end-stage renal disease. Although individual case reports have described an improvement in sleep apnoea following kidney transplantation, there have been no longitudinal studies of a case series to determine what proportion of patients with sleep apnoea improve.
  
  
  METHODS
  Dialysis-dependent patients awaiting kidney transplantation and pre-dialysis patients with an identified living donor kidney had overnight polysomnography, which was repeated several months after successful kidney transplantation. Patients were divided into apnoeic and non-apnoeic groups based on an apneoa-hypopnoea index (AHI) > 10/h during pre-transplant polysomnography and, following transplantation, apnoeic patients were further divided into responders and non-responders based on >50% reduction in AHI and/or AHI < 10/h.
  
  
  RESULTS
  Eighteen patients (11 men, 7 women), aged 27-65, were studied. Pre-transplant sleep apnoea was present in 11 of 18 (61%) patients. Although transplantation was associated with a significant reduction in blood urea nitrogen and serum creatinine, there were no significant changes in AHI (pre vs post: 20.2 +/- 15.1 vs 23.5 +/- 21.3). Among the 11 apnoeic patients, only three met the criteria for a significant improvement ('responder'). There were no patient characteristics, sleep apnoea indices or renal function changes that distinguished responders from non-responders.
  
  
  CONCLUSIONS
  Sleep apnoea improves in a minority of patients with end-stage renal disease following successful kidney transplantation. Specific determinants of improvement were not identified.
authors.affiliation: Department of Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4N1.
authors.forename: Jaime M
authors.initials: JM
authors.lastname: Beecroft
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Zaltzman
authors.forename: Ramesh
authors.initials: R
authors.lastname: Prasad
authors.forename: Galo
authors.initials: G
authors.lastname: Meliton
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Hanly
mesh_terms: D000328:Adult; D000368:Aged; D002318:Cardiovascular Diseases / Q000517:prevention & control; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications* / Q000628:therapy*; D016030:Kidney Transplantation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D017286:Polysomnography / Q000379:methods; D006435:Renal Dialysis; D012119:Respiration; D012891:Sleep Apnea Syndromes / Q000150:complications*; D016896:Treatment Outcome