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60/100

✓ Peer-reviewed alzhub usefulness score 60 out of 100. Mild cognitive impairment

Topic: Risk, prevention and care in population studies

Background Mild behavioral impairment (MBI) and subjective cognitive decline (SCD) are dementia risk states, and potentially represent neurobehavioral and neurocognitive manifestations, respectively, of early stage neurodegeneration. Both MBI and SCD predict incident cognitive decline and dementia, are associated with known dementia biomarkers, and are both represented in the NIA-AA research framework for AD in Stage 2 (preclinical disease). Objective To assess the associations of MBI and SCD, alone and in combination, with incident cognitive and functional decline in a population of older adults. We tested the hypothesis that MBI and SCD confer additive risk for decline. Methods Cognitively normal participants were followed up annually at Alzheimer's Disease Centers. Logistic regression assessed the relationship between baseline classification (MBI-SCD-, MBI-SCD+, MBI+SCD-, or MBI+SCD+) and 3-year outcome. Results Of 2,769 participants (mean age=76), 1,536 were MBI-SCD-, 254 MBI-SCD+, 743 MBI+SCD-, and 236 MBI+SCD+. At 3 years, 349 (12.6%) declined to CDR >0, including 23.1% of the MBI+group, 23.5% of the SCD+group, and 30.9% of the intersection group of both MBI+and SCD+participants. Compared to SCD-MBI-, we observed an ordinal progression in risk (ORs [95% CI]): 3.61 [2.42-5.38] for MBI-SCD+ (16.5% progression), 4.76 [3.57-6.34] for MBI+SCD- (20.7%), and 8.15 [5.71-11.64] for MBI+SCD+(30.9%). Conclusion MBI and SCD together were associated with the greatest risk of decline. These complementary dementia risk syndromes can be used as simple and scalable methods to identify high-risk patients for workup or for clinical trial enrichment.

Key findings

Both MBI and SCD predict incident cognitive decline and dementia, are associated with known dementia biomarkers, and are both represented in the NIA-AA research framework for AD in Stage 2 (preclinical disease).
Results Of 2,769 participants (mean age=76), 1,536 were MBI-SCD-, 254 MBI-SCD+, 743 MBI+SCD-, and 236 MBI+SCD+.
Compared to SCD-MBI-, we observed an ordinal progression in risk (ORs [95% CI]): 3.61 [2.42-5.38] for MBI-SCD+ (16.5% progression), 4.76 [3.57-6.34] for MBI+SCD- (20.7%), and 8.15 [5.71-11.64] for MBI+SCD+(30.9%).
Conclusion MBI and SCD together were associated with the greatest risk of decline.

Why it matters

In this study of 2,769 cognitively normal older adults, mild behavioral impairment and subjective cognitive decline each predicted cognitive and functional decline over three years, and having both conferred the highest risk. These findings support using these states to identify people at risk, but the study tested no treatment or prevention.

Study details

Participants2,769
Effect size12.6%; 23.1%; 23.5%
Evidence strengthLow

How this study scored 60/100

Published in a peer-reviewed journal. Scored zero for study design and randomised / blinded because the record does not state it.

Component	Points	Why
Journal tier	7 / 10	Tier 3 — peer-reviewed journal (Journal of Alzheimer's disease : JAD)
Journal's citation record	2 / 4	Journal of Alzheimer s Disease: journal h-index 218 (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	3 / 5	2021 — within 6 year(s) of the newest study here
Sample size	3 / 4	2,769 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	5 / 7	Cited 170 times (OpenAlex, 2026-10-10)
Citations per year	4 / 5	24.3 citations a year over 7 year(s) since 2021
Impact for its field and year	4 / 6	Cited 16.4× the average for papers of its field and year (OpenAlex FWCI)
Cited by studies here	3 / 6	Cited by 10 other studies in this library
Still being cited	3 / 4	Cited 92 times in 2024–2026 (2026 still in progress; OpenAlex)
Senior author's track record	4 / 4	Last-listed author Eric Edward Smith: h-index 127 (OpenAlex, whole career)
Institution's track record	1 / 3	University of Calgary: institution h-index 1,028 (OpenAlex)
Multi-centre collaboration	1 / 3	OpenAlex lists 3 institution(s) in 1 country
Indexed in PubMed	2 / 2	Indexed in PubMed (PMID 33554909)
Free to read	2 / 2	Free to read
Total	60 / 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

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APA 7th

Ismail, Z., McGirr, A., Gill, S., Hu, S., Forkert, N. D., & Smith, E. E. (2021). Mild Behavioral Impairment and Subjective Cognitive Decline Predict Cognitive and Functional Decline. Journal of Alzheimer's disease : JAD. https://doi.org/10.3233/jad-201184

Vancouver

Ismail Z, McGirr A, Gill S, Hu S, Forkert ND, Smith EE. Mild Behavioral Impairment and Subjective Cognitive Decline Predict Cognitive and Functional Decline. Journal of Alzheimer's disease : JAD. 2021. doi:10.3233/jad-201184. PMID: 33554909.

BibTeX

@article{ismail2021-33554909,
  author  = {Ismail, Z. and McGirr, A. and Gill, S. and Hu, S. and Forkert, N. D. and Smith, E. E.},
  title   = {{Mild Behavioral Impairment and Subjective Cognitive Decline Predict Cognitive and Functional Decline}},
  journal = {Journal of Alzheimer's disease : JAD},
  year    = {2021},
  doi     = {10.3233/jad-201184},
  pmid    = {33554909},
  url     = {https://doi.org/10.3233/jad-201184}
}

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