The Prevalence of Mild Cognitive Impairment in a Convenience Sample of 202 Gulf War Veterans

Abstract

Gulf War Illness (GWI) is a chronic, multisymptom disorder estimated to affect approximately 25–32% of Gulf War veterans (GWVs). Cognitive dysfunction is a common symptom of GWI. On the continuum of cognitive decline, mild cognitive impairment (MCI) is conceptualized as a transitional phase between normal aging and dementia. Individuals with MCI exhibit cognitive decline but have relatively spared activities of daily function and do not meet criteria for dementia. The current study sought to investigate the prevalence of MCI in a convenience sample of 202 GWVs (median age: 52 years; 18% female). Twelve percent of the sample (median age: 48 years) had MCI according to an actuarial neuropsychological criterion, a rate materially higher than expected for this age group. GWVs with MCI also had a smaller hippocampal volume and a thinner parietal cortex, higher rates of current posttraumatic stress disorder and major depressive disorder compared to GWVs without MCI. Because people with MCI are more likely to progress to dementia compared to those with normal cognition, these results may portend future higher rates of dementia among deployed GWVs.

The prevalence of mild cognitive impairment in Gulf War veterans: a follow-up study

“…However, a recent meta-analysis/systematic review estimated that 7.6% of adults between 55 and 59 years have MCI ( Lu et al, 2021 ). Notably, that estimate is lower than the 12% that we recently reported in a convenience sample of 202 middle-aged (median age 52 years old) GW veterans ( Chao, 2020 ).…”

Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) Clinical Normative Data for Gulf War Veterans

“…Possible relationships between exposures sustained during the Gulf War, differences in brain morphology, emotional distress, and MCI as GWVs age have been explored in recent GWV studies 14 . As GWVs represent a closed cohort from a specific point in history, the cognitive age-corrected profile presented in the current study may serve as a useful yardstick comparison for future studies continuing this line of investigation into potential decline beyond what might be expected with normal aging (e.g., further exploration of factors related to a suggested trend toward earlier onset of MCI in this cohort).…”

“…A subsequent review expanded on these findings to suggest that deficits in neuropsychological and motor functioning may be exacerbated by chemical exposures and comorbid mood disorders 13 . In addition, a higher-than-expected rate of mild cognitive impairment (MCI) and a related concern about high rates of dementia in later life for a sample of GWVs have been suggested 14 …”

“…13 In addition, a higher-than-expected rate of mild cognitive impairment (MCI) and a related concern about high rates of dementia in later life for a sample of GWVs have been suggested. 14 Given the somewhat equivocal findings highlighted in the extant literature above, clinicians treating GWVs with cognitive concerns are presented with a nebulous evidence base for clinical decisionmaking. Although cognitive deficits are thought by many to be a core feature of Gulf War Illness (GWI), clinically derived neurocognitive data sets of widely used measures are unavailable.…”

Evaluation of delayed LNFPIII treatment initiation protocol on improving long-term behavioral and neuroinflammatory pathology in a mouse model of Gulf War Illness

“…Veterans with GWI also have higher rates of mood dysfunction ( Binder et al, 1999 ; Hom et al, 1997 ; Lindem et al, 2003 ; Sillanpaa et al, 1997 ) that might impact other reported symptoms (i.e., cognitive and memory complaints) and performance in neuropsychological tests of sustained attention, motor coordination, and executive functioning ( Binder et al, 1999 ; Lindem et al, 2003 ; Sillanpaa et al, 1997 ). These behavioral deficits may be linked to altered brain architecture, as clinical MRI studies point to abnormalities in brain areas, such as the hippocampus and cerebellum, that govern these behaviors ( Calley et al, 2010 ; Chao, 2020 ; Chao et al, 2010 , 2011 , 2015 , 2016 ; Christova et al, 2017 ; Gopinath et al, 2012 ; Hubbard et al, 2014 ; James et al, 2017 ; Van Riper et al, 2017 ; Washington et al, 2020 ; Wylie et al, 2019 ; Zhang et al, 2020 , 2021 ).…”