Olfactory Deficits in Normal Aging and Alzheimer's Disease in the Polish Elderly Population

Alzheimer's disease (AD) is the most frequent cause of dementia. For this reason, a simple, reliable, and inexpensive method of early AD detection is urgently required. The location of neuropathological changes in AD patients indicates the potential diagnostic utility of olfactory tests. The purpose of this study was to compare odor identification performance among Polish subjects and to define the correlation between olfactory deficits and cognitive impairment. Olfactory identification performance was established in AD patients, and young and elderly healthy subjects using the Pocket Smell Test. AD Assessment Scale, the cognitive subscale, was used to evaluate cognitive functioning in the elderly participants. Compared with young subjects, the elderly individuals exhibited a diminished capacity to identify odors. AD patients also identified significantly fewer odors than healthy participants of the same age. In both the AD patients and the elderly control group, odor identification ability correlated with performance in cognitive tests. It may be concluded that deficits in olfactory identification occur in AD and may be valuable as an indicator of this condition.