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Failure to identify odors may be an early sign of cognitive impairment. A recent study included persons aged 65 years or older without dementia (males and females, n = 1037) [1]. They were asked to identify 40 different odors, and their success rate was scored. Also, a brain MRI and a battery of cognitive tests were performed. Follow-up at 2 and 4 years in 757 participants showed that low baseline scores correlated with cognitive decline and the appearance of Alzheimer’s disease. MRI hippocampal volume did not show predictive utility in this cohort. The investigators suggested that the inexpensive smell test could be useful as a predictor of future cognitive impairment.

Author(s)

  • Amos Pines
    Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel

Citations

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