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Sensory impairment and dementia risk among older adults in rural South Africa
Muqi Guo, Darina T. Bassil, Meagan T. Farrell, Ryan Gregory Wagner, Brent Tipping, Nomsa Brightness Mahlalela, David Kapaon, Stephen Tollman et al.. Alzheimer s & Dementia, 2025-07-01
Topic: Risk, prevention and care in population studies
Half of the participants were over 70, with no formal education. Sensory impairments were common, especially in dementia cases. Distance vision impairment was linked to both MCI and dementia, while near vision and hearing impairments were associated with dementia. Hearing impairment also predicted higher dementia probability after 2 years. Addressing sensory impairments is key to dementia prevention in rural South Africa. HIGHLIGHTS: Among rural older South Africans, 65% had near vision impairment and 47% had hearing impairment. Distance or near vision and hearing impairments are linked to an increased risk of dementia. Distance vision impairment is also associated with a higher risk of mild cognitive impairment (MCI). Dementia risk was seven times higher with distance vision, near vision and hearing impairment. Hearing impairment increased the probability of dementia 2 years later in initially non-demented individuals.
Key findings
- Half of the participants were over 70, with no formal education.
- Sensory impairments were common, especially in dementia cases.
- Distance vision impairment was linked to both MCI and dementia, while near vision and hearing impairments were associated with dementia.
- Hearing impairment also predicted higher dementia probability after 2 years.
- Addressing sensory impairments is key to dementia prevention in rural South Africa.
Why it matters
This study found that vision and hearing impairments were linked to higher risk of dementia in older adults in rural South Africa, and hearing impairment predicted higher dementia probability two years later. It suggests that addressing sensory impairments may be important for dementia prevention in this population.
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Study details
- Participants567
- Evidence strengthModerate
How this study scored 46/100
Published in a peer-reviewed journal. Scored zero for study design, effect reported and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Alzheimer s & Dementia) |
| Journal's citation record | 2 / 4 | Alzheimer s & Dementia: journal h-index 228 (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 | 3 / 5 | Rated “moderate” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 4 / 5 | 2025 — within 3 year(s) of the newest study here |
| Sample size | 2 / 4 | 567 participants |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 3 / 3 | Studied in people (participant count stated) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 1 / 7 | Cited 1 times (OpenAlex, 2026-10-10) |
| Citations per year | 0 / 5 | 0.3 citations a year over 3 year(s) since 2025 |
| Impact for its field and year | 1 / 6 | Cited 0.6× 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 | 0 / 4 | Cited 1 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 4 / 4 | Last-listed author Lisa F. Berkman: h-index 130 (OpenAlex, whole career) |
| Institution's track record | 3 / 3 | Harvard University: institution h-index 3,235 (OpenAlex) |
| Multi-centre collaboration | 2 / 3 | OpenAlex lists 6 institution(s) in 2 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 40693440) |
| Free to read | 2 / 2 | Free to read |
| Total | 46 / 100 | — |
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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. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.
APA 7th
Guo, M., Bassil, D. T., Farrell, M. T., Wagner, R. G., Tipping, B., Mahlalela, N. B., et al. (2025). Sensory impairment and dementia risk among older adults in rural South Africa. Alzheimer s & Dementia. https://doi.org/10.1002/alz.70513
Vancouver
Guo M, Bassil DT, Farrell MT, Wagner RG, Tipping B, Mahlalela NB, et al. Sensory impairment and dementia risk among older adults in rural South Africa. Alzheimer s & Dementia. 2025. doi:10.1002/alz.70513. PMID: 40693440.
BibTeX
@article{guo2025-40693440,
author = {Guo, Muqi and Bassil, Darina T. and Farrell, Meagan T. and Wagner, Ryan Gregory and Tipping, Brent and Mahlalela, Nomsa Brightness and Kapaon, David and Tollman, Stephen and others},
title = {{Sensory impairment and dementia risk among older adults in rural South Africa}},
journal = {Alzheimer s \& Dementia},
year = {2025},
doi = {10.1002/alz.70513},
pmid = {40693440},
url = {https://doi.org/10.1002/alz.70513}
}
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