Abstract
Background
Olfactory dysfunction and subjective memory complaints (SMC) have been separately reported in Alzheimer's disease (AD) patients and in people at risk of developing AD or at a prodromal phase of the disease, such as mild cognitive impairment (MCI). However, SMC and olfactory dysfunction have also been reported in the healthy elderly and in other neurodegenerative diseases such as Parkinson's disease. The current study was designed to examine the association of frequency of forgetting and the olfactory threshold, discrimination, and identification in the healthy, community elderly.
Methods
The sample compromised 107 participants (29 male and 78 female) derived from an ongoing longitudinal cohort of 530 healthy, elderly participants in Western Australia. The Sniffin' Sticks was used to measure the different olfactory functions. The Sniffin' Sticks provides four different scores including the olfactory threshold, discrimination, identification, and a total score (namely, TDI). Subjective memory complaints were tested using two measures: i) a single “yes/no” question derived from CAMDX-R, and ii) the frequency of forgetting subscale of Memory Functioning Questionnaire.
Results
There was no significant difference between male/female and SMC/control groups with respect to age, performance on Mini Mental Status Examination (MMSE), and premorbid IQ. The SMC group was significantly different from the control group on olfactory threshold (P<0.05) and identification (P<0.05). There was a significant correlation between age and olfactory threshold. The frequency of forgetting showed significant correlations with olfactory discrimination and identification (both significant at: P<0.01). Age was the best predictor of threshold, while frequency of forgetting was a better predictor for olfactory discrimination and identification in comparison to age, sex, and depression.
Conclusions
There were significant associations between SMC and those olfactory functions related to memory for olfactory stimuli. Though further investigation is needed for a definitive conclusion, these findings have important implications for the development of future screening instruments and better diagnostic criteria for AD.
Olfactory dysfunction and subjective memory complaints (SMC) have been separately reported in Alzheimer's disease (AD) patients and in people at risk of developing AD or at a prodromal phase of the disease, such as mild cognitive impairment (MCI). However, SMC and olfactory dysfunction have also been reported in the healthy elderly and in other neurodegenerative diseases such as Parkinson's disease. The current study was designed to examine the association of frequency of forgetting and the olfactory threshold, discrimination, and identification in the healthy, community elderly.
Methods
The sample compromised 107 participants (29 male and 78 female) derived from an ongoing longitudinal cohort of 530 healthy, elderly participants in Western Australia. The Sniffin' Sticks was used to measure the different olfactory functions. The Sniffin' Sticks provides four different scores including the olfactory threshold, discrimination, identification, and a total score (namely, TDI). Subjective memory complaints were tested using two measures: i) a single “yes/no” question derived from CAMDX-R, and ii) the frequency of forgetting subscale of Memory Functioning Questionnaire.
Results
There was no significant difference between male/female and SMC/control groups with respect to age, performance on Mini Mental Status Examination (MMSE), and premorbid IQ. The SMC group was significantly different from the control group on olfactory threshold (P<0.05) and identification (P<0.05). There was a significant correlation between age and olfactory threshold. The frequency of forgetting showed significant correlations with olfactory discrimination and identification (both significant at: P<0.01). Age was the best predictor of threshold, while frequency of forgetting was a better predictor for olfactory discrimination and identification in comparison to age, sex, and depression.
Conclusions
There were significant associations between SMC and those olfactory functions related to memory for olfactory stimuli. Though further investigation is needed for a definitive conclusion, these findings have important implications for the development of future screening instruments and better diagnostic criteria for AD.
| Original language | English |
|---|---|
| Pages (from-to) | T573 |
| Number of pages | 1 |
| Journal | Alzheimer's and Dementia |
| Volume | 4 |
| Issue number | 4S Part 17 |
| DOIs | |
| Publication status | Published - 2008 |
| Externally published | Yes |
| Event | Alzheimer's Association International Conference 2008 - Chicago, United States Duration: 26 Jul 2008 → 31 Jul 2008 |