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Relationship between serum TSH level and Alzheimer disease pathology
Byung Wook Choi, Sungmin Kang, Hae Won Kim. Alzheimer's & Dementia, 2020
Topic: Amyloid, tau and blood-test diagnosis
Abstract Background Thyroid dysfunction is one of the risk factors associated with cognitive impairment, including Alzheimer disease (AD). The aim of this study was to evaluate the association between serum TSH level and AD pathology through biochemical assays, positron emission tomography (PET) imaging, and cognitive performance tests. Method Sixty‐nine subjects without overt hypothyroidism who underwent [ 18 F]‐florbetaben PET were included in this prospective cross‐sectional study. The serum levels of free thyroxine (fT4) and thyroid stimulating hormone (TSH) were quantified using radioimmunoassays. The Mini‐Mental State Examination, Digit Span Memory Test, Boston Naming Test, and the Rey‐Osterrieth Complex Figure Test and Recognition Trial were performed to assess cognitive function. Differences in cerebral amyloid‐β (Aβ) burden, which is represented by standardized 18 F‐florbetaben uptake value ratio (SUVR), were compared between high‐normal TSH (TSH ≥ 2.5 μIU/mL) and low‐normal (TSH < 2.5 μIU/mL) groups. Multiple linear regression analyses, adjusted for age and sex, were performed to evaluate the relationship between thyroid hormone levels and cerebral Aβ burden, and between thyroid hormone levels and cognitive function. Result The cerebral Aβ burden in the high‐normal TSH group was significantly higher than in the low‐normal TSH group (SUVR 1.53 vs. 1.35, p = 0.009). The fT4 levels were negatively correlated with cerebral Aβ burden ( β = ‐0.250, p = 0.033), and TSH levels were positively correlated with cerebral Aβ burden ( β = 0.243, p = 0.018). The fT4 level was also positively associated with cognitive function, as inferred from cognitive performance evaluation. Conclusion Serum TSH level is associated with cerebral Aβ burden. The fT4 and TSH levels showed negative and positive correlation with cerebral Aβ burden, respectively. Our findings suggest that serum TSH level, especially in subject with high‐normal serum TSH level, may contribute to AD development.
Key findings
- Abstract Background Thyroid dysfunction is one of the risk factors associated with cognitive impairment, including Alzheimer disease (AD).
- Result The cerebral Aβ burden in the high‐normal TSH group was significantly higher than in the low‐normal TSH group (SUVR 1.53 vs. 1.35, p = 0.009).
- The fT4 level was also positively associated with cognitive function, as inferred from cognitive performance evaluation.
- Conclusion Serum TSH level is associated with cerebral Aβ burden.
- Our findings suggest that serum TSH level, especially in subject with high‐normal serum TSH level, may contribute to AD development.
Why it matters
In 69 people without overt hypothyroidism, higher-normal TSH levels were associated with greater cerebral amyloid-beta burden on PET imaging, and free thyroxine was positively associated with cognitive function. This suggests a link between thyroid hormone levels and Alzheimer's-related brain changes, but it is a cross-sectional study and does not show that treating thyroid levels prevents or cures Alzheimer's.
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Study details
- Evidence strengthLow
How this study scored 31/100
Published in a leading specialty 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 | 9 / 10 | Tier 2 — leading specialty 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 | 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 | 2 / 5 | 2020 — within 10 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 | 1 / 7 | Cited 2 times (OpenAlex, 2026-10-10) |
| Citations per year | 0 / 5 | 0.2 citations a year over 8 year(s) since 2020 |
| Impact for its field and year | 1 / 6 | Cited 0.2× 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 | 2 / 4 | Last-listed author Hae Won Kim: h-index 22 (OpenAlex, whole career) |
| Institution's track record | 0 / 3 | Keimyung University Dongsan Hospital: institution h-index 171 (OpenAlex) |
| Multi-centre collaboration | 2 / 3 | OpenAlex lists 4 institution(s) in 1 country |
| Indexed in PubMed | 1 / 2 | Not in PubMed, but has a DOI |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 31 / 100 | — |
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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
Choi, B. W., Kang, S., & Kim, H. W. (2020). Relationship between serum TSH level and Alzheimer disease pathology. Alzheimer's & Dementia. https://doi.org/10.1002/alz.041210
Vancouver
Choi BW, Kang S, Kim HW. Relationship between serum TSH level and Alzheimer disease pathology. Alzheimer's & Dementia. 2020. doi:10.1002/alz.041210.
BibTeX
@article{choi2020-fa86d36f,
author = {Choi, Byung Wook and Kang, Sungmin and Kim, Hae Won},
title = {{Relationship between serum TSH level and Alzheimer disease pathology}},
journal = {Alzheimer's \& Dementia},
year = {2020},
doi = {10.1002/alz.041210},
url = {https://doi.org/10.1002/alz.041210}
}