title: Obstructive sleep apnea and delirium: exploring possible mechanisms.
abstract: BACKGROUND
  Obstructive sleep apnea (OSA) is a medical disorder strongly associated with multiple comorbidities and postoperative complications. Current evidence suggests that OSA disturbs fundamental biochemical processes, leading to low-grade systemic inflammation and oxidative stress. Animal models have shown that OSA may lead to apoptosis of central neurons. In clinical studies, oxygen desaturation index and sleep fragmentation have been shown to be independently associated with cognitive dysfunction. Moreover, in several studies, patients with OSA were shown to have decreased brain activation in multiple brain areas.
  The possibility of an association between OSA and delirium has been highlighted in several case reports. The first prospective study of the possible link between apnea and delirium showed that the presence of OSA was independently associated with the occurrence of delirium after knee replacement surgery.
  
  
  CONCLUSIONS
  Therefore, we suggest that OSA should be considered as a risk factor for delirium, and clinicians should assess patients for OSA and related risk factors prior to surgery. However, further research is required to shed light on the mechanisms connecting these disorders and on whether the treatment of OSA affects the incidence of delirium.
authors.affiliation: Department of Internal Medicine, Saint Joseph Hospital, Chicago, IL, USA, amirrakhimov1@gmail.com.
authors.forename: Aibek E
authors.initials: AE
authors.lastname: Mirrakhimov
authors.forename: Carey L
authors.initials: CL
authors.lastname: Brewbaker
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Krystal
authors.forename: Madan M
authors.initials: MM
authors.lastname: Kwatra
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology; D001921:Brain / Q000503:physiopathology; D003072:Cognition Disorders / Q000503:physiopathology / Q000523:psychology; D003693:Delirium / Q000175:diagnosis / Q000503:physiopathology*; D004195:Disease Models, Animal; D006801:Humans; D009474:Neurons / Q000502:physiology; D018384:Oxidative Stress / Q000502:physiology; D010100:Oxygen / Q000097:blood; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis / Q000503:physiopathology*
chemical_list: D010100:Oxygen