Risk of Parkinson Disease Among Service Members at Marine Corps Base Camp Lejeune, 2023, Stroupe et al

JAMA Neurol. Published online May 15, 2023. doi:10.1001/jamaneurol.2023.1168
https://jamanetwork.com/journals/jamaneurology/article-abstract/2805037


Key points

Question Is Parkinson disease risk increased in military service members who were stationed at Marine Corps Base Camp Lejeune, North Carolina, during 1975-1985 when the water supply was contaminated with trichloroethylene and other volatile organic compounds?

Findings This cohort study of 340 489 service members found that the risk of Parkinson disease was 70% higher in Camp Lejeune veterans compared with veterans stationed at a Marine Corps base where water was not contaminated. In veterans without Parkinson disease, risk was also significantly higher for several prodromal features of Parkinson disease.

Meaning The study’s findings suggest that exposure to trichloroethylene in water may increase the risk of Parkinson disease; millions worldwide have been and continue to be exposed to this ubiquitous environmental contaminant.


Abstract

Importance An increased risk of Parkinson disease (PD) has been associated with exposure to the solvent trichloroethylene (TCE), but data are limited. Millions of people in the US and worldwide are exposed to TCE in air, food, and water.

Objective To test whether the risk of PD is higher in veterans who served at Marine Corps Base Camp Lejeune, whose water supply was contaminated with TCE and other volatile organic compounds (VOCs), compared with veterans who did not serve on that base.

Design, Setting, and Participants This population-based cohort study examined the risk for PD among all Marines and Navy personnel who resided at Camp Lejeune, North Carolina (contaminated water) (n = 172 128), or Camp Pendleton, California (uncontaminated water) (n = 168 361), for at least 3 months between 1975 and 1985, with follow-up from January 1, 1997, until February 17, 2021. Veterans Health Administration and Medicare databases were searched for International Classification of Diseases diagnostic codes for PD or other forms of parkinsonism and related medications and for diagnostic codes indicative of prodromal disease. Parkinson disease diagnoses were confirmed by medical record review.

Exposures Water supplies at Camp Lejeune were contaminated with several VOCs. Levels were highest for TCE, with monthly median values greater than 70-fold the permissible amount.

Main Outcome and Measures Risk of PD in former residents of Camp Lejeune relative to residents of Camp Pendleton. In those without PD or another form of parkinsonism, the risk of being diagnosed with features of prodromal PD were assessed individually and cumulatively using likelihood ratio tests.

Results Health data were available for 158 122 veterans (46.4%). Demographic characteristics were similar between Camp Lejeune (5.3% women, 94.7% men; mean [SD] attained age of 59.64 [4.43] years; 29.7% Black, 6.0% Hispanic, 67.6% White; and 2.7% other race and ethnicity) and Camp Pendleton (3.8% women, 96.2% men; mean [SD] age, 59.80 [4.62] years; 23.4% Black, 9.4% Hispanic, 71.1% White, and 5.5% other race and ethnicity). A total of 430 veterans had PD, with 279 from Camp Lejeune (prevalence, 0.33%) and 151 from Camp Pendleton (prevalence, 0.21%). In multivariable models, Camp Lejeune veterans had a 70% higher risk of PD (odds ratio, 1.70; 95% CI, 1.39-2.07; P < .001). No excess risk was found for other forms of neurodegenerative parkinsonism. Camp Lejeune veterans also had a significantly increased risk of prodromal PD diagnoses, including tremor, anxiety, and erectile dysfunction, and higher cumulative prodromal risk scores.

Conclusions and Relevance The study’s findings suggest that the risk of PD is higher in persons exposed to TCE and other VOCs in water 4 decades ago. Millions worldwide have been and continue to be exposed to this ubiquitous environmental contaminant.

 

There is almost no research on the health impacts of the vast majority of chemicals and pollution people are exposed to, because the basis of medical research, control groups, is almost never available.

Medicine really needs better methodologies than this standard approach, quality control groups are only rarely available.

IMO almost all disease is immunological, in the sense of a foreign threat the immune system reacts to, but it isn't only pathogens. And for the most part we are completely blind here. How do we even assess the health impacts of microplastics when everyone has them now? Medicine needs to move from a statistical approach towards a full data approach. The standard methods take way too long and in most circumstances aren't even possible.

It took decades to see the obvious impact of vaporising a neurotoxin (lead) in the atmosphere because of those weak methodologies. And it is easy to weaponize it to cover up disaster, as we are seeing with COVID and how there is no control group anymore, and that fact is used to minimize everything happening.

 

i agree. I think at some point there will be a reckoning, but for now the preliminary links between our environment and (chronic) illness are being treated as inconvenient truths.

 

Adding to this, didn't keep the article so lost the source, but trichloroethylene used to be quite common some decades ago, was even used to decaffeinate coffee. It's present in many water sources as a result. It's still used, though far less than before.