Brain Injury and Later-Life Cognitive Impairment and Neuropathology: The Honolulu-Asia Aging Study

Article type: Research Article

Authors: Chosy, E. Julia^{a; *} | Gross, Noele^a | Meyer, Marnie^a | Liu, Catherine Y.^a | Edland, Steven D.^b | Launer, Lenore J.^c | White, Lon R.^a

Affiliations: [a] Pacific Health Research and Education Institute, Honolulu, HI, USA | [b] University of California at San Diego, San Diego, CA, USA | [c] National Institute on Aging, National Institutes of Health, Bethesda, MD, USA

Correspondence: [*] Correspondence to: E. Julia Chosy, PhD, 3375 Koapaka Street, Suite I-540, Honolulu, HI 96819, USA. Tel.: +1 808 564 5458; Fax: +1 808 524 5559; E-mail: ejchosy@phrei.org.

Abstract: Background:Findings are inconsistent regarding the role of traumatic head injury in the subsequent development of neurologic outcomes. Objective:Examine the relationship between head injury and later cognitive impairment. Methods:A sample of 3,123 Japanese-American men was assessed for history of head injury and evaluated for cognitive impairment using the Cognitive Abilities Screening Instrument (CASI). For a subsample of 676 respondents, neuropathologic results from those with and without head injury were compared. Results:Although the crude model showed an association between history of head injury and later severe cognitive impairment, the relationship lost significance in the adjusted model (OR = 1.320, CI: 0.90–1.93), regardless of time between injury and impairment. Similar to cognitive impairment, hippocampal sclerosis was observed significantly more in the brains of respondents with a history of head injury in the crude model, but the relationship weakened in the adjusted model (OR = 1.462, CI: 0.68–3.12). After adjustment, decedents with a head injury demonstrated marginally higher brain weight (OR = 1.003, CI: 1.00–1.01). Conclusion:We did not find a relationship between head injury and subsequent cognitive decline in this cohort. The neuropathology results also displayed no strong association between history of head injury and specific brain lesions and characteristics. These results support other findings in prospective cohorts. However, they could be influenced by the demographic make-up of the sample (male Japanese-Americans) or by the observation that the majority reported only a single head injury.

Keywords: Alzheimer’s disease, brain lesions, cognitive dysfunction, dementia, Honolulu-Asia Aging Study, neuropathology, traumatic brain injury

DOI: 10.3233/JAD-190053

Journal: Journal of Alzheimer's Disease, vol. 73, no. 1, pp. 317-325, 2020