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Odour identification as a marker for postoperative cognitive dysfunction: a pilot study.

P Rentowl·C D Hanning
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Abstract

The onset of postoperative cognitive dysfunction is delayed in some elderly surgical patients and the condition may persist. Increasing age is a risk factor for both postoperative cognitive dysfunction and dementia. Major surgery may unmask an underlying dementia; we report findings of a pilot study designed to inform this hypothesis. Impaired odour identification ability is a characteristic of the preclinical phase of some neuro-degenerative diseases. This pilot study was designed to establish whether odour identification deficit is a marker for postoperative cognitive dysfunction, particularly in elderly patients genetically predisposed to develop late-onset Alzheimer's disease. We found no association between odour identification ability and postoperative cognitive dysfunction in 53 patients aged 62-86, undergoing major non-cardiac surgery under general anaesthesia. Our pilot study showed that a high number of patients genetically predisposed to develop Alzheimer's disease is required to test the utility of odour identification as a marker for postoperative cognitive dysfunction.

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AgedAged, 80 and overAlzheimer DiseaseAnesthesia, GeneralApolipoproteins ECognition DisordersFemaleGenetic Predisposition to DiseaseGenotypeHumansMaleMiddle AgedNeuropsychological TestsOdorantsOlfaction DisordersPilot ProjectsPostoperative ComplicationsPostoperative PeriodPsychometricsEvaluation StudyJournal ArticleResearch Support, Non-U.S. Gov't

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P Rentowl, C D Hanning. 2004. Odour identification as a marker for postoperative cognitive dysfunction: a pilot study.. https://doi.org/10.1111/j.1365-2044.2004.03678.x

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