Related Experiment Video
Updated: Jul 10, 2026
06:27
An Olfactory Preference Test for Measuring Olfactory Hedonic Biases in Mouse Models of Depression
Published on: July 11, 2025
Olfactory Impairment and Depression: A Systematic Review and Meta-Analysis.
Henry Bode1,2, Linnea Sjöberg1, Ingrid Ekström1
1Aging Research Center, Department of Neurobiology, Care Sciences and Society, Karolinska Institute, Stockholm, Sweden.
JAMA Otolaryngology-- Head & Neck Surgery
|July 9, 2026
Summary
Subjective olfactory impairment (SOI) is moderately linked to depression in older adults. Objective olfactory impairment (OOI) shows a weaker link, but is relevant in older individuals and those with anosmia, suggesting shared mechanisms.
Area of Science:
- Gerontology
- Neuroscience
- Psychiatry
Background:
- Depression and olfactory impairment are common in older adults, impacting quality of life and cognitive function.
- Olfactory dysfunction may serve as a potential marker for late-life depression.
Purpose of the Study:
- To quantify the association between objective olfactory impairment (OOI) and subjective olfactory impairment (SOI) with depression.
- To examine potential moderators in population-based studies.
Main Methods:
- Systematic review and meta-analysis of 23 population-based studies (N=187,056).
- Searched PubMed, Embase, EBSCOhost, and Web of Science.
- Assessed risk of bias using the Newcastle-Ottawa Scale; performed random-effects meta-analyses.
Main Results:
- Subjective olfactory impairment (SOI) was consistently associated with depression (OR, 1.56; 95% CI, 1.19-2.05).
- Objective olfactory impairment (OOI) showed an association with objective depression (OR, 1.26; 95% CI, 1.02-1.56), which attenuated after bias adjustment.
- OOI association remained robust in older adults (≥65 years) and individuals with anosmia.
Conclusions:
- SOI demonstrates a consistent association with depression, potentially reflecting self-perception.
- OOI's association with depression is less consistent but relevant in specific subgroups, suggesting overlapping mechanisms in late life.
- Further longitudinal and mechanistic studies are needed to clarify causal pathways and clinical implications.
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