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70/100

✓ Peer-reviewed alzhub usefulness score 70 out of 100. How common it is

Topic: Risk, prevention and care in population studies

Plain-language summary

Objective To determine whether TBI with loss of consciousness (LOC) is associated with an increased risk for clinical and neuropathologic findings of Alzheimer disease (AD), Parkinson disease (PD), and other dementias. Primary hypothesis was that TBI with LOC would be associated with increased risk for AD and neurofibrillary tangles. Results Of 7130 participants (2879 [40.4%] men; overall mean [SD] age, 79.9 [6.9] years), 865 reported a history of TBI with LOC. Traumatic brain injury with LOC was associated with Lewy bodies (any Lewy body in ACT: RR for TBI with LOC >1 hour, 2.64; 95% CI, 1.40-4.99; Lewy bodies in substantia nigra and/or locus ceruleus in ACT: RR for TBI with LOC >1 hour, 3.30; 95% CI, 1.71-6.38; Lewy bodies in frontal or temporal cortex in ACT: RR for TBI with LOC >1 hour, 5.73; 95% CI, 2.18-15.0; ROS and MAP: RR for TBI with LOC ≤1 hour, 1.64; 95% CI, 1.00-2.70; pooled RR for TBI with LOC ≤1 hour, 1.59; 95% CI, 1.06-2.39) and microinfarcts (any cortical microinfarct in ROS and MAP: RR for TBI with LOC >1 hour, 2.12; 95% CI, 1.12-4.01; pooled RR for TBI with LOC >1 hour, 1.58; 95% CI, 1.06-2.35). Conclusions and relevance Pooled clinical and neuropathologic data from 3 prospective cohort studies indicate that TBI with LOC is associated with risk for Lewy body accumulation, progression of parkinsonism, and PD, but not dementia, AD, neuritic plaques, or neurofibrillary tangles.

What this study adds

Evidence grade: Moderate

This is a follow-up (cohort) study of 7,130 participants. In 7,130 older adults from three pooled long-term studies with brain autopsy data, a self-reported head injury with loss of consciousness was linked to Lewy bodies, worsening parkinsonism and Parkinson disease. Reported effect size: 40.4%.

Taken from this record’s own fields, not from reading the paper. The grade is assigned from the abstract’s wording; what that means.

Cite this study APA, Vancouver, BibTeX · download .bib or .ris

APA 7th

Crane, P. K., Gibbons, L. E., Dams-O'Connor, K., Trittschuh, E., Leverenz, J. B., Keene, C. D., et al. (2016). Association of Traumatic Brain Injury With Late-Life Neurodegenerative Conditions and Neuropathologic Findings. JAMA neurology. https://doi.org/10.1001/jamaneurol.2016.1948

Vancouver

Crane PK, Gibbons LE, Dams-O'Connor K, Trittschuh E, Leverenz JB, Keene CD, et al. Association of Traumatic Brain Injury With Late-Life Neurodegenerative Conditions and Neuropathologic Findings. JAMA neurology. 2016. doi:10.1001/jamaneurol.2016.1948. PMID: 27400367.

BibTeX

@article{crane2016-27400367,
  author  = {Crane, P. K. and Gibbons, L. E. and Dams-O'Connor, K. and Trittschuh, E. and Leverenz, J. B. and Keene, C. D. and Sonnen, J. and Montine, T. J. and others},
  title   = {{Association of Traumatic Brain Injury With Late-Life Neurodegenerative Conditions and Neuropathologic Findings}},
  journal = {JAMA neurology},
  year    = {2016},
  doi     = {10.1001/jamaneurol.2016.1948},
  pmid    = {27400367},
  url     = {https://doi.org/10.1001/jamaneurol.2016.1948}
}

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How to read this study

Design: this is a follow-up (cohort) study. People are observed over time and not assigned to anything, so an association can reflect other differences between groups. Look at how long follow-up lasted, how many dropped out, and whether the authors adjusted for age, education and other health conditions.
Size: the record lists 7,130 participants. Ask whether that is enough for the question, and who they were.
Effect: the record reports “40.4%”. A statistically significant result can still be small in daily life.

What the evidence grade means here

This page is graded moderate. alzhub.org assigns the grade automatically from keywords in the abstract, not from reading the paper. Moderate means the abstract mentions a cohort, case-control or longitudinal design. It can add at most 5 of the 100 points in the study score, and it is a label about design, not a verdict on whether the findings are true.

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Key findings

Objective To determine whether TBI with loss of consciousness (LOC) is associated with an increased risk for clinical and neuropathologic findings of Alzheimer disease (AD), Parkinson disease (PD), and other dementias.
Primary hypothesis was that TBI with LOC would be associated with increased risk for AD and neurofibrillary tangles.
Results Of 7130 participants (2879 [40.4%] men; overall mean [SD] age, 79.9 [6.9] years), 865 reported a history of TBI with LOC.
Traumatic brain injury with LOC was associated with Lewy bodies (any Lewy body in ACT: RR for TBI with LOC >1 hour, 2.64; 95% CI, 1.40-4.99; Lewy bodies in substantia nigra and/or locus ceruleus in ACT: RR for TBI with LOC >1 hour, 3.30; 95% CI, 1.71-6.38; Lewy bodies in frontal or temporal cortex in ACT: RR for TBI with LOC >1 hour, 5.73; 95% CI, 2.18-15.0; ROS and MAP: RR for TBI with LOC ≤1 hour, 1.64; 95% CI, 1.00-2.70; pooled RR for TBI with LOC ≤1 hour, 1.59; 95% CI, 1.06-2.39) and microinfarcts (any cortical microinfarct in ROS and MAP: RR for TBI with LOC >1 hour, 2.12; 95% CI, 1.12-4.01; pooled RR for TBI with LOC >1 hour, 1.58; 95% CI, 1.06-2.35).
Conclusions and relevance Pooled clinical and neuropathologic data from 3 prospective cohort studies indicate that TBI with LOC is associated with risk for Lewy body accumulation, progression of parkinsonism, and PD, but not dementia, AD, neuritic plaques, or neurofibrillary tangles.

Why it matters

In 7,130 older adults from three pooled long-term studies with brain autopsy data, a self-reported head injury with loss of consciousness was linked to Lewy bodies, worsening parkinsonism and Parkinson disease. The researchers had expected to find more Alzheimer's disease and tangles, but found no association with dementia, Alzheimer's, plaques or tangles. These are associations, not proof of cause, and the study tested no treatment or prevention.

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Study details

Study designcohort study
Participants7,130
Effect size40.4%
Evidence strengthModerate

How this study scored 70/100

Published in a leading specialty journal, and it is a cohort study following people over time. Scored zero for randomized / blinded because the record does not state it.

Component	Points	Why
Journal tier	9 / 10	Tier 2 — leading specialty journal (JAMA neurology)
Journal's citation record	2 / 4	JAMA Neurology: journal h-index 235 (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	1 / 5	2016 — within 20 year(s) of the newest study here
Sample size	3 / 4	7,130 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)
Randomized / blinded	0 / 2	No randomization or blinding stated — scores zero (not stated in the record — scored 0)
Times cited	6 / 7	Cited 443 times (OpenAlex, 2026-10-10)
Citations per year	4 / 5	36.9 citations a year over 12 year(s) since 2016
Impact for its field and year	5 / 6	Cited 37.3× the average for papers of its field and year (OpenAlex FWCI)
Cited by studies here	3 / 6	Cited by 17 other studies in this library
Still being cited	3 / 4	Cited 100 times in 2024–2026 (2026 still in progress; OpenAlex)
Senior author's track record	2 / 4	Last-listed author Eric B. Larson: h-index 33 (OpenAlex, whole career)
Institution's track record	3 / 3	University of Washington: institution h-index 3,540 (OpenAlex)
Multicenter collaboration	2 / 3	OpenAlex lists 8 institution(s) in 1 country
Indexed in PubMed	2 / 2	Indexed in PubMed (PMID 27400367)
Free to read	0 / 2	Behind a paywall — scores zero
Total	70 / 100	—

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