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Olfaction and Aging: A Mini-Review
Attems J, Walker L, Jellinger KA.. Gerontology, 2015-05-09
Topic: Risk, prevention and care in population studies
Decreased olfactory function is very common in the older population, being present in >50% of individuals aged between 65 and 80 years and in 62-80% of those >80 years of age. Smell dysfunction significantly influences physical well-being, quality of life, nutritional status as well as everyday safety and is associated with increased mortality. Multiple factors contribute to age-related olfactory sensory loss, including nasal engorgement, cumulative damage of the olfactory epithelium from environmental insults, a reduction in mucosal metabolizing enzymes, sensory loss of receptor cells to odorants, and changes in neurotransmitter and neuromodulator systems. In addition, structural and functional abnormalities of the olfactory epithelium, olfactory bulb, central olfactory cortex, and basic olfactory circuitry, which are related to the neuronal expression of aberrant proteins in these areas, may result in olfactory sensory impairment in aging and neurodegenerative diseases. Impaired odour identification is associated with a decrease in cognitive abilities and memory decline. A reduction in the sense of smell is considered to potentially represent an early and important warning of neurodegenerative disorders, particularly of Parkinson's disease and Alzheimer's disease, and, in mild cognitive impairment, olfactory impairment may herald progression to dementia. Further investigations of the potential role of olfactory dysfunction in the early diagnosis and treatment of neurodegenerative diseases are warranted.
Key findings
- Smell dysfunction significantly influences physical well-being, quality of life, nutritional status as well as everyday safety and is associated with increased mortality.
- In addition, structural and functional abnormalities of the olfactory epithelium, olfactory bulb, central olfactory cortex, and basic olfactory circuitry, which are related to the neuronal expression of aberrant proteins in these areas, may result in olfactory sensory impairment in aging and neurodegenerative diseases.
- Impaired odour identification is associated with a decrease in cognitive abilities and memory decline.
Why it matters
This review notes that impaired odour identification is associated with decreased cognitive abilities and memory decline, and that in mild cognitive impairment olfactory impairment may signal progression to dementia. It suggests smell loss could serve as an early warning of neurodegenerative disorders including Alzheimer's disease, but does not establish any treatment or prevention.
Study details
- Evidence strengthLow
How this study scored 43/100
Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Gerontology) |
| Journal's citation record | 2 / 4 | Gerontology: journal h-index 151 (OpenAlex, 2026-10-29) |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 2015 — within 20 year(s) of the newest study here |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 6 / 7 | Cited 325 times (OpenAlex, 2026-10-10) |
| Citations per year | 4 / 5 | 25.0 citations a year over 13 year(s) since 2015 |
| Impact for its field and year | 2 / 6 | Cited 2.1× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 0 / 6 | No other study in this library cites it |
| Still being cited | 3 / 4 | Cited 73 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 4 / 4 | Last-listed author K. A. Jellinger: h-index 137 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | Newcastle University: institution h-index 932 (OpenAlex) |
| Multi-centre collaboration | 0 / 3 | OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 25968962) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 43 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
Attems, J., Walker, L., & Jellinger, K. A. (2015). Olfaction and Aging: A Mini-Review. Gerontology. https://doi.org/10.1159/000381619
Vancouver
Attems J, Walker L, Jellinger KA. Olfaction and Aging: A Mini-Review. Gerontology. 2015. doi:10.1159/000381619. PMID: 25968962.
BibTeX
@article{attems2015-25968962,
author = {Attems, J. and Walker, L. and Jellinger, K. A.},
title = {{Olfaction and Aging: A Mini-Review}},
journal = {Gerontology},
year = {2015},
doi = {10.1159/000381619},
pmid = {25968962},
url = {https://doi.org/10.1159/000381619}
}
Studies this one cites
Referenced by this study and also in the alzhub library, so you can read them here.