Agent Orange Exposure and Dementia Diagnosis in US Veterans of the Vietnam Era

Steven Martinez; Kristine Yaffe; Yixia Li; Amy L. Byers; Carrie B. Peltz; Deborah E. Barnes

doi:10.1001/jamaneurol.2020.5011

Comment

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February 2, 2021

Political-Economic-Social Morality of Wars

Paul Nelson, MS, MD | Family Health Care, P.C.- Retired

During a 41-year career as a primary physician, it wasn't often that members of our military would reveal to me the inhumanity that our military fostered with the use of Agent Orange. Related to this were the rescue missions that were required to "pickup" beleaguered platoons with aircraft to simultaneously pick up the surrounded troops and shower the surrounding combat zone with literally thousands of bullets unloaded almost simultaneously.
With just a vague sense of imagination, I could not imagine the severity of imminent catastrophe that the person in front of me must have endured...and endured again by its retelling. Fortunately, my nurses always knew to leave his exam-room's door open for me when he came in for a visit.
The Agent Orange effects were greatly magnified by their emotional disruptive processes.

CONFLICT OF INTEREST: None Reported

Brief Report

January 25, 2021

Agent Orange Exposure and Dementia Diagnosis in US Veterans of the Vietnam Era

厂迟别惫别苍听惭补谤迟颈苍别锄,听叠厂^1,2; 碍谤颈蝉迟颈苍别听驰补蹿蹿别,听惭顿^1,3,4,5; 驰颈虫颈补听尝颈,听惭笔贬^1,2; et al Amy L.听Byers,听PhD, MPH^1,3,6; Carrie B.听Peltz,听PhD^1,2; Deborah E.听Barnes,听PhD, MPH^1,3,5

Author Affiliations Article Information

¹San Francisco Veterans Affairs Health Care System, San Francisco, California
²Northern California Institute for Research and Education鈥揟he Veterans Health Research Institute, San Francisco
³Department of Psychiatry and Behavioral Sciences, University of California, San Francisco, San Francisco
⁴Department of Neurology, University of California, San Francisco, San Francisco
⁵Department of Epidemiology & Biostatistics, University of California, San Francisco, San Francisco
⁶Division of Geriatrics, Department of Medicine, University of California, San Francisco, San Francisco

JAMA Neurol. 2021;78(4):473-477. doi:10.1001/jamaneurol.2020.5011

Key Points

Question听 Is Agent Orange exposure associated with an increased risk of dementia diagnosis in US veterans of the Vietnam era?

Findings听 In this study of more than 300鈥�000 veterans, those with Agent Orange exposure in their medical records were nearly twice as likely as those without exposure to receive a dementia diagnosis, even after adjusting for medical and psychiatric comorbidities and other variables.

Meaning听 Per this analysis, Agent Orange exposure may increase risk of dementia.

Abstract

Importance听 Agent Orange is a powerful herbicide that contains dioxin and was used during the Vietnam War. Although prior studies have found that Agent Orange exposure is associated with increased risk of a wide range of conditions, including neurologic disorders (eg, Parkinson disease), metabolic disorders (eg, type 2 diabetes), and systemic amyloidosis, the association between Agent Orange and dementia remains unclear.

Objective听 To examine the association between Agent Orange exposure and incident dementia diagnosis in US veterans of the Vietnam era.

Design, Setting, and Participants听 This cohort study included Veterans Health Administration data from October 1, 2001, and September 30, 2015, with up to 14 years of follow-up. Analyses were performed from July 2018 to October 2020. A 2% random sample of US veterans of the Vietnam era who received inpatient or outpatient Veterans Health Administration care, excluding those with dementia at baseline, those without follow-up visits, and those with unclear Agent Orange exposure status.

Exposures听 Presumed Agent Orange exposure documented in electronic health record.

Main Outcomes and Measures听 Fine-Gray competing risk models were used to compare the time to dementia diagnosis (with age as the time scale) for veterans with vs without presumed Agent Orange exposure (as per medical records), adjusting for demographic variables and medical and psychiatric comorbidities.

Results听 The total sample was 511鈥�189 individuals; after exclusions, 316鈥�351 were included in analyses. Veterans were mostly male (n鈥�=鈥�309鈥�889 [98.0%]) and had a mean (SD) age of 62 (6.6) years; 38鈥�121 (12.1%) had presumed Agent Orange exposure. Prevalence of most conditions, including Parkinson disease, diabetes, and amyloidosis, was similar at baseline among veterans with and without Agent Orange exposure. After adjusting for demographic variables and comorbidities, veterans exposed to Agent Orange were nearly twice as likely as those not exposed to receive a dementia diagnosis over a mean (SD) of 5.5 (3.8) years of follow-up (1918 of 38鈥�121 [5.0%] vs 6886 of 278鈥�230 [2.5%]; adjusted hazard ratio: 1.68 [95% CI, 1.59-1.77]). Veterans with Agent Orange exposure developed dementia at a mean of 1.25 years earlier (at a mean [SD] age of 67.5 [7.0] vs 68.8 [8.0] years).

Conclusions and Relevance听 Veterans with Agent Orange exposure were nearly twice as likely to be diagnosed with dementia, even after adjusting for the competing risk of death, demographic variables, and medical and psychiatric comorbidities. Additional studies are needed to examine potential mechanisms underlying the association between Agent Orange exposure and dementia.

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Agent Orange Exposure and Dementia Diagnosis in US Veterans of the Vietnam Era