Is postoperative cognitive dysfunction a risk factor for dementia? A cohort follow-up study

Br J Anaesth. 2013 Jun;110 Suppl 1:i92-7. doi: 10.1093/bja/aes466. Epub 2012 Dec 28.


Background: Postoperative cognitive dysfunction (POCD) is a common complication in elderly patients after major surgery. An association between POCD and the development of dementia has been suspected. In this study, we assessed if POCD was a risk factor for the occurrence of dementia.

Methods: Danish patients enrolled between November 1994 and October 2000 in the two International Studies of Postoperative Cognitive Dysfunction (ISPOCD 1 and 2) were followed until July 1, 2011. Cognitive performance was assessed at three time points: before operation, at 1 week, and 3 months after surgery, using a neuropsychological test battery. The time of (first) occurrence of dementia after surgery was assessed using the National Patient Register and the Psychiatric Central Research Register. Recorded dementia diagnoses (ICD-8 and ICD-10) were: Alzheimer's disease, vascular dementia, frontotemporal dementia, or dementia without specification. The risk of dementia according to POCD was assessed in the Cox regression models.

Results: A total of 686 patients with a median age of 67 [inter-quartile range (IQR) 61-74] yr were followed for a median of 11.1 (IQR 5.2-12.6) yr. Only 32 patients developed dementia during follow-up. The hazard ratio (95% CI) for any dementia diagnoses in patients with POCD at 1 week (n=118) and POCD at 3 months (n=57) after surgery compared with those without POCD was 1.16 (0.48-2.78), P=0.74, and 1.50 (0.51-4.44); P=0.47, respectively.

Conclusions: POCD was not significantly associated with registered dementia over a median follow-up of 11 yr.

Keywords: dementia; postoperative cognitive dysfunction; postoperative complications.

Publication types

  • Multicenter Study

MeSH terms

  • Adult
  • Aged
  • Cognition Disorders / diagnosis
  • Cognition Disorders / epidemiology
  • Cognition Disorders / etiology
  • Cognition Disorders / psychology*
  • Dementia / epidemiology
  • Dementia / etiology*
  • Denmark / epidemiology
  • Depression / epidemiology
  • Depression / etiology
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Middle Aged
  • Neuropsychological Tests
  • Postoperative Complications / diagnosis
  • Postoperative Complications / epidemiology
  • Postoperative Complications / psychology*
  • Postoperative Period
  • Risk Factors