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Association Between Age at Diabetes Onset and Subsequent Risk of Dementia
Barbiellini Amidei C, Fayosse A, Dumurgier J, Machado-Fragua MD, Tabak AG, van Sloten T, Kivimäki M, Dugravot A et al.. JAMA, 2021-04-01
Topic: Risk, prevention and care in population studies
Importance Trends in type 2 diabetes show an increase in prevalence along with younger age of onset. While vascular complications of early-onset type 2 diabetes are known, the associations with dementia remains unclear. Objective To determine whether younger age at diabetes onset is more strongly associated with incidence of dementia. Design, setting, and participants Population-based study in the UK, the Whitehall II prospective cohort study, established in 1985-1988, with clinical examinations in 1991-1993, 1997-1999, 2002-2004, 2007-2009, 2012-2013, and 2015-2016, and linkage to electronic health records until March 2019. The date of final follow-up was March 31, 2019. Exposures Type 2 diabetes, defined as a fasting blood glucose level greater than or equal to 126 mg/dL at clinical examination, physician-diagnosed type 2 diabetes, use of diabetes medication, or hospital record of diabetes between 1985 and 2019. Main outcomes and measures Incident dementia ascertained through linkage to electronic health records. Results Among 10 095 participants (67.3% men; aged 35-55 years in 1985-1988), a total of 1710 cases of diabetes and 639 cases of dementia were recorded over a median follow-up of 31.7 years. Dementia rates per 1000 person-years were 8.9 in participants without diabetes at age 70 years, and rates were 10.0 per 1000 person-years for participants with diabetes onset up to 5 years earlier, 13.0 for 6 to 10 years earlier, and 18.3 for more than 10 years earlier. In multivariable-adjusted analyses, compared with participants without diabetes at age 70, the hazard ratio (HR) of dementia in participants with diabetes onset more than 10 years earlier was 2.12 (95% CI, 1.50-3.00), 1.49 (95% CI, 0.95-2.32) for diabetes onset 6 to 10 years earlier, and 1.11 (95% CI, 0.70-1.76) for diabetes onset 5 years earlier or less; linear trend test (P Conclusions and relevance In this longitudinal cohort study with a median follow-up of 31.7 years, younger age at onset of diabetes was significantly associated with higher risk of subsequent dementia.
Key findings
- Objective To determine whether younger age at diabetes onset is more strongly associated with incidence of dementia.
- Results Among 10 095 participants (67.3% men; aged 35-55 years in 1985-1988), a total of 1710 cases of diabetes and 639 cases of dementia were recorded over a median follow-up of 31.7 years.
- In multivariable-adjusted analyses, compared with participants without diabetes at age 70, the hazard ratio (HR) of dementia in participants with diabetes onset more than 10 years earlier was 2.12 (95% CI, 1.50-3.00), 1.49 (95% CI, 0.95-2.32) for diabetes onset 6 to 10 years earlier, and 1.11 (95% CI, 0.70-1.76) for diabetes onset 5 years earlier or less; linear trend test (P < .001) indicated a graded association between age at onset of type 2 diabetes and dementia.
Why it matters
This cohort study examined whether younger age at type 2 diabetes onset is more strongly associated with the incidence of dementia. It reports dementia rates and a hazard ratio comparing participants with diabetes onset more than 10 years earlier to those without diabetes at age 70.
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Study details
- Study designcohort study
- Participants95
- Effect size67.3%
- Evidence strengthModerate
How this study scored 77/100
Published in a top-tier journal, and it is a cohort study following people over time. Scored zero for randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 10 / 10 | Tier 1 — top-tier general journal (JAMA) |
| Journal's citation record | 4 / 4 | JAMA: journal h-index 1,011 (OpenAlex, 2026-10-29) |
| Study design | 7 / 12 | A cohort study following people over time |
| 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 | 3 / 5 | 2021 — within 6 year(s) of the newest study here |
| Sample size | 1 / 4 | 95 participants |
| Effect reported | 2 / 3 | Effect reported as a number, without an interval or test |
| 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 | 6 / 7 | Cited 352 times (OpenAlex, 2026-10-10) |
| Citations per year | 5 / 5 | 50.3 citations a year over 7 year(s) since 2021 |
| Impact for its field and year | 5 / 6 | Cited 36.4× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 3 / 6 | Cited by 23 other studies in this library |
| Still being cited | 4 / 4 | Cited 211 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 4 / 4 | Last-listed author Archana Singh‐Manoux: h-index 124 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | University College London: institution h-index 2,029 (OpenAlex) |
| Multi-centre collaboration | 3 / 3 | OpenAlex lists 11 institution(s) in 5 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 33904867) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 77 / 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. 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
Barbiellini Amidei, C., Fayosse, A., Dumurgier, J., Machado-Fragua, M. D., Tabak, A. G., van Sloten, T., et al. (2021). Association Between Age at Diabetes Onset and Subsequent Risk of Dementia. JAMA. https://doi.org/10.1001/jama.2021.4001
Vancouver
Barbiellini Amidei C, Fayosse A, Dumurgier J, Machado-Fragua MD, Tabak AG, van Sloten T, et al. Association Between Age at Diabetes Onset and Subsequent Risk of Dementia. JAMA. 2021. doi:10.1001/jama.2021.4001. PMID: 33904867.
BibTeX
@article{barbielliniamidei2021-33904867,
author = {Barbiellini Amidei, C. and Fayosse, A. and Dumurgier, J. and Machado-Fragua, M. D. and Tabak, A. G. and van Sloten, T. and Kivimäki, M. and Dugravot, A. and others},
title = {{Association Between Age at Diabetes Onset and Subsequent Risk of Dementia}},
journal = {JAMA},
year = {2021},
doi = {10.1001/jama.2021.4001},
pmid = {33904867},
url = {https://doi.org/10.1001/jama.2021.4001}
}
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