Tuesday, December 3, 2024

Nazi Medicine: In NEJM 2024

In 2024, NEJM had two articles on Nazism and 1930s medicine, as covered by NEJM.

The first 2024 article was, Abi-Rached & Brandt, Nazism and the Journal, 390:1157-61.  

https://www.nejm.org/doi/full/10.1056/NEJMp2307319 

Abi-Rached's article focused on a 1935 article, Recent Changes in German Health Insurance under the Hitler Government, May 30, 1935, Davis, NEJM 212:1037-42.

https://www.nejm.org/doi/full/10.1056/NEJM193505302122206

The Davis article broadly discussed features and emphases of Nazi social medicine and policy, with one mention that Jewish physicians were excluded.  (There was also 1 follow-up letter & reply).

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The second 2024 NEM article was, Reede JY et al., Eugenics, Nazism, and the Journal, 391:e50 [transcript].

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Harvard Gazette covered the Abi-Rached & Brandt article in May 2024.   "How do you read organization's silence over the rise of Nazism?" by Alvin Powell.

https://news.harvard.edu/gazette/story/2024/05/how-do-you-read-organizations-silence-over-rise-of-nazism/

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The two 2024 NEJM articles (with shared authorship) focus on the relative silence of NEJM on German medicine, save for the single Davis article.   

A comparison was made with JAMA (which had somewhat more articles on Nazism).

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First, I hope that the citation to Davis led some readers to the 1935 original article, easily available via the NEJM archive.   Many themes in German medicine of the 1930s echo today - urban versus rural, public health vs treatment of disease, politics of physician organizations, specialists vs generalists, funding, etc.

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Second, the deliberate 2024 focus on medical journal archives may miss an important point.  There have a been a number of popular history books in the last few years about Nazism and pro-German sentiment in the US during the 1930s.   (Lindbergh vs Roosevelt, Duffy, 2010; Those Angry Days 1939-1941, Olson, 2013, Hitler's American Friends, Hart, 2018, others).

Since NEJM is an academic journal, of special interest is the late Stephen Norwood's book, "The Third Reich in the Ivory Tower," Cambridge Univ Press, 2011.     

And focusing on Boston and Massachusetts - Available open access is a 2008 chapter by Norwood in the journal, American Jewish History, Johns Hopkins MUSE, page 38, "Legitimzing  Nazis: Harvard University and the Hitler Regime 1933-1937."

https://www.scribd.com/document/212918635/Harvard-e-Hitler-33-37

https://drive.google.com/file/d/1jF0W51YVlSdKZ0jlnY5u0bSHkWmtimxW/view?usp=sharing

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The relative silence of NEJM, and the brevity of Davis' reference to Jewish physicians, becomes clearer in the context of work like Norwood's.    

It is difficult to view 1934 except through the lens of the Hoocaust and 1945.   However, when 1933 and 1934 were  unfolding, Nazism had a far smaller role in world politics and even the frightful early persecution of Jewish physicians would have been comparable to the treatmentt of Black physicians in the US (among numerous examples), which also likely had minimal if any coverage in JAMA and NEJM in the same year.  [Re Black physicians in the US and Jewish physicians in Germany, see Hitler's American Model, Whitman, 2017].

The limited coverage of Nazism in NEJM can be appropriately paired with topics like pro-Nazism at the same time at Harvard (Norwood), although this takes us out of the narrow domain of medical journal studies.   While, in the Powell interview, Brandt comments, "The Davis piece is remarkable for its opacity, its ability to focus on a [economic] reform and not have any context around it."   But the Abi-Rached Brandt article also takes a rather narrow focus, focusing on NEJM with relatively little on the more general partly pro-Nazi society as documented by Norwood, Hart, and others.

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There is a recent book on quite sharp leftward and rightward swings in AMA politics, 1880s-1980s, in which the 1930s chapter is pertinent.  Peter A Swenson, 2021, Disorder: A history of reform, reaction, and money in American medicine.   

Cut FDA Final Brief Text

 

Where do the two briefs have the tightest overlap?

The ACLA and AMP briefs overlap significantly in their critiques of the FDA's final rule regulating laboratory-developed tests (LDTs). The key areas of overlap include:

  1. Major Questions Doctrine:

    • Both briefs assert that the FDA’s regulation of LDTs represents a significant expansion of regulatory authority requiring clear Congressional authorization, which is absent.
    • Both highlight that Congress has repeatedly declined to authorize such regulation, underscoring the overreach.
  2. Definition of a Device under the FDCA:

    • Both argue that LDTs are not “devices” as defined by the FDCA because they involve professional services rather than tangible, manufactured products. They emphasize that LDTs are not commercially distributed and are used within a single laboratory.
  3. Conflict with CLIA:

    • Both emphasize that CLIA already provides comprehensive oversight for LDTs, regulating their validity and reliability.
    • They argue that FDA regulation would create unnecessary duplication, conflict with CLIA, and undermine its well-established framework.
  4. Economic and Practical Consequences:

    • Both highlight the severe financial and operational burdens the FDA’s rule would impose on laboratories, including billions in compliance costs, disruption of innovation, and reduced patient access to LDTs.
    • They underscore the likelihood of laboratories exiting the market, further harming patient care.
  5. Arbitrary and Capricious Rulemaking:

    • Both briefs argue that the FDA’s rule is arbitrary and capricious, lacking a clear rationale or evidence to justify the dramatic shift in regulatory oversight.
    • They critique the FDA’s reliance on enforcement discretion policies as inadequate and inconsistent.
  6. Practice of Medicine Exemption:

    • Both highlight statutory protections for healthcare professionals under the FDCA, arguing that the FDA’s rule unlawfully infringes on the practice of medicine by regulating professional services.

These shared arguments reflect a unified stance from the lab industry, emphasizing that the FDA’s final rule oversteps statutory boundaries, conflicts with existing regulation, and would harm patient care and innovation.

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I don't have access to the government's response, that is, the FDA's response and final brief.   However, what can we infer about the FDA's responses and counter-arguments, from the moving parties' final briefs.

While the FDA’s final brief is not available, we can infer key aspects of its arguments and counterpoints based on how the ACLA and AMP briefs respond to and refute them. Here’s an analysis of what the FDA likely argued and how the moving parties addressed those points:


1. Authority to Regulate LDTs

FDA’s Likely Argument:

  • The FDA likely argued that LDTs qualify as "devices" under the FDCA because they involve in vitro diagnostic (IVD) systems, which the agency has historically regulated.
  • The FDA may have claimed it has continuously asserted authority over LDTs since the 1970s but has exercised enforcement discretion until now.

Response by ACLA and AMP:

  • Both briefs dispute the FDA’s historical authority, emphasizing that LDTs are professional services, not commercially distributed devices.
  • They point out that the FDA has inconsistently applied its claimed authority, with decades of non-enforcement undermining its position.
  • The AMP brief argues that relying on broad definitions of terms like "device" (e.g., “apparatus” or “contrivance”) would sweep in unrelated medical procedures, exceeding statutory intent.

2. Commercial Distribution Requirement

FDA’s Likely Argument:

  • LDTs involve “commercial distribution” because laboratories provide testing services for a fee, and the FDA’s statutory authority covers commercially provided services.

Response by ACLA and AMP:

  • Both briefs argue that “commercial distribution” under the FDCA applies to tangible goods transferred to third parties, not internal laboratory procedures.
  • AMP highlights that applying this interpretation to LDTs would render the statutory language meaningless, as procedures cannot be “distributed.”

3. Compatibility with CLIA

FDA’s Likely Argument:

  • The FDA likely argued that CLIA and FDA regulation target different aspects of test oversight: CLIA focuses on laboratory operations and analytical validity, while the FDA focuses on clinical validity and patient safety.

Response by ACLA and AMP:

  • Both briefs reject this distinction, asserting that CLIA already ensures both analytical and clinical validity through proficiency testing and other mechanisms.
  • AMP argues that FDA regulation would create unnecessary duplication and conflict, effectively undermining the existing CLIA framework.

4. Major Questions Doctrine

FDA’s Likely Argument:

  • The FDA likely attempted to downplay the significance of its rule under the major questions doctrine, arguing that its regulation of LDTs is consistent with its long-standing statutory authority.

Response by ACLA and AMP:

  • Both briefs counter that the FDA’s sudden assertion of broad regulatory authority over LDTs constitutes a “transformative expansion” requiring explicit Congressional authorization, which has not been granted.
  • They highlight Congress’s repeated refusal to authorize such regulation, suggesting that the FDA’s actions lack clear statutory backing.

5. Economic and Practical Impacts

FDA’s Likely Argument:

  • The FDA may have argued that the costs associated with compliance are justified by the need to ensure the safety and efficacy of LDTs, given their critical role in patient care.

Response by ACLA and AMP:

  • Both briefs emphasize the disproportionate costs and practical burdens, projecting billions in compliance costs, laboratory closures, and diminished patient access to innovative tests.
  • They argue that these impacts are avoidable under the current CLIA framework, which effectively regulates test quality without stifling innovation.

6. Practice of Medicine Exemption

FDA’s Likely Argument:

  • The FDA may have argued that the practice of medicine exemption under the FDCA does not shield laboratories or affiliated entities from regulation, as it is narrowly tailored to individual practitioners.

Response by ACLA and AMP:

  • Both briefs assert that the exemption protects not only individual practitioners but also their affiliated entities (e.g., laboratories), as regulation of one inevitably impacts the other.
  • AMP emphasizes that holding laboratories liable for LDT practices would undermine Congress’s intent to shield healthcare providers from regulatory overreach.

7. FDA’s Rulemaking Process

FDA’s Likely Argument:

  • The FDA likely defended its rulemaking as consistent with administrative law principles, claiming it carefully considered stakeholder input and based the rule on statutory mandates.

Response by ACLA and AMP:

  • Both briefs argue the rule is arbitrary and capricious, citing inadequate justification for the regulatory shift and failure to address the historical reliance on CLIA oversight.
  • AMP specifically critiques the FDA’s reliance on non-binding enforcement discretion policies, calling them insufficient and inconsistent.

Inferred Strategy of the FDA

  • The FDA likely sought to expand the statutory definitions and historical interpretations of the FDCA to encompass LDTs, focusing on patient safety as a justification for regulatory oversight.
  • It probably downplayed the potential conflicts with CLIA and the economic impacts of the rule, while asserting that it has the authority to act in the absence of explicit Congressional prohibition.

Conclusion

From the ACLA and AMP responses, it is clear that the FDA’s arguments hinge on broad statutory interpretations, historical assertions of authority, and a separation of regulatory focus between CLIA and the FDCA. However, both briefs effectively challenge these positions by emphasizing statutory text, legislative history, and the practical consequences of the FDA’s actions. This alignment suggests a strong unified opposition to the FDA’s rule within the lab industry.

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What arguments are unique to ACLA or unique to AMP?

there are several noteworthy arguments unique to either the ACLA or AMP closing briefs, reflecting their differing emphases and approaches to opposing the FDA’s final rule:


Arguments Unique to the ACLA Closing Brief

  1. FDA's Inconsistent Enforcement History:

    • ACLA places significant emphasis on the FDA’s inconsistent enforcement of its purported authority over LDTs, using this as evidence that the agency itself has historically acknowledged its limited authority in this area.
  2. Focus on Economic Disruption:

    • While both briefs discuss economic impacts, ACLA provides a broader analysis of how the rule would disrupt the entire clinical laboratory sector, emphasizing the financial burden on smaller labs and its chilling effect on innovation.
  3. Role of Laboratories as Service Providers:

    • ACLA delves deeper into the distinction between laboratories as service providers (under CLIA) versus manufacturers (under the FDCA). This framing underscores that LDTs are services, not products, and challenges the FDA’s attempt to conflate the two.
  4. Critique of FDA’s Ad Hoc Enforcement Policies:

    • ACLA specifically critiques the FDA’s reliance on non-binding "enforcement discretion" policies to mitigate the rule's effects, arguing that such policies highlight the rule’s impracticality and lack of clarity.

Arguments Unique to the AMP Closing Brief

  1. Practice of Medicine Exemption:

    • AMP places greater emphasis on the FDCA’s practice of medicine exemption, arguing that the FDA’s rule undermines this long-standing protection for healthcare professionals and their affiliated entities.
    • AMP highlights how the exemption applies to individual practitioners and their associated laboratories, reinforcing that the rule would unlawfully penalize laboratories for activities intrinsic to medical practice.
  2. Conflict with CLIA’s Comprehensive Regulation:

    • While ACLA critiques the overlap between FDA and CLIA oversight, AMP goes further by arguing that the FDA’s rule would render key CLIA provisions superfluous, creating direct regulatory conflicts.
    • AMP specifically points to how CLIA already addresses both analytical and clinical validity, undermining the FDA’s justification for additional oversight.
  3. Detailed Examination of the Major Questions Doctrine:

    • AMP provides a more in-depth discussion of the major questions doctrine, analyzing how Congress’s repeated refusal to grant the FDA authority over LDTs highlights the absence of clear Congressional authorization for the rule.
  4. Use of Analogies to Surgical Procedures:

    • AMP draws a novel analogy between the development of LDTs and the design of surgical procedures, arguing that the FDA’s expansive interpretation of “device” could criminalize standard medical practices like surgery, thereby demonstrating the unworkability of the FDA's position.
  5. Critique of FDA’s Statutory Interpretation:

    • AMP takes a nuanced approach to challenging the FDA’s interpretation of statutory terms like “apparatus” and “contrivance,” employing canons of statutory construction to argue that the FDA’s definitions are overly broad and inconsistent with Congressional intent.

Summary of Unique Contributions

  • ACLA focuses on the practical and economic impacts of the rule, emphasizing the financial and operational burdens on laboratories, and critiques the FDA’s historical inconsistencies in asserting its authority.
  • AMP, on the other hand, provides a more legalistic critique, emphasizing statutory construction, the practice of medicine exemption, and the conflict with CLIA, while employing analogies and canons of interpretation to challenge the FDA’s arguments.

These distinctions reflect complementary strategies, with ACLA targeting the rule’s real-world implications and AMP focusing on the legal framework. Together, they form a robust opposition to the FDA’s final rule.

Monday, December 2, 2024

Law School Questions

 

Write three essay questions for a third-year law student course on health & regulatory law, where this case was a major teaching case this semester.

Essay Question 1: Regulatory Jurisdiction and Statutory Interpretation

The FDA's assertion of regulatory authority over laboratory-developed tests (LDTs) has been challenged by both ACLA and AMP on statutory and jurisdictional grounds. Drawing from their arguments and relevant statutory language, address the following:

  • Discuss the jurisdictional boundaries between CLIA and the FDCA. How does this case illustrate the challenges of overlapping regulatory frameworks?
  • Evaluate the FDA’s interpretation of LDTs as "devices" under the FDCA. Is this interpretation consistent with the statutory language and legislative intent? Why or why not?
  • Apply the major questions doctrine to this case. Should the FDA’s regulation of LDTs fall under this doctrine, and if so, why does it matter?

In your response, consider both the practical implications for laboratories and the legal principles governing agency authority.


Essay Question 2: Economic and Public Health Implications of Regulatory Overreach

Both ACLA and AMP emphasize the economic and public health impacts of the FDA’s rule. In a well-structured essay, analyze:

  • How does the rule’s potential economic burden on laboratories weigh against the FDA's stated goals of ensuring patient safety and test accuracy?
  • Do the existing CLIA regulations adequately address concerns about the analytical and clinical validity of LDTs, or is there a compelling need for FDA oversight?
  • Consider how the rule might disproportionately affect smaller laboratories or those serving underserved populations. What broader public health issues could arise?

Use examples from the briefs and discuss whether the FDA adequately justified its position in light of these consequences.


Essay Question 3: The Role of Enforcement Discretion in Administrative Law

The FDA has historically used enforcement discretion to regulate LDTs, a point heavily critiqued in the ACLA and AMP briefs. Write an essay discussing:

  • What is the legal and practical role of enforcement discretion in administrative law?
  • How does the FDA's reliance on enforcement discretion to mitigate the impacts of its LDT rule affect its credibility and the clarity of its regulatory framework?
  • Should courts view reliance on enforcement discretion as a strength or a weakness in agency rulemaking? Justify your position with reference to this case and broader principles of administrative law.

In your response, address how the courts might balance the flexibility of enforcement discretion with the need for predictability and fairness in regulation.


DE LAAT Exercise PD

 https://www.nature.com/articles/s41531-024-00641-1


Heart-rate chest-strap Participants wore chest straps with a Polar H7 heart rate (HR) monitor (Polar Electro Oy, Kempele, Finland) starting five minutes before, and continuing throughout every exercise session. The target HR for each participant was defined as 80% of his/her maximum HR. Maximum HR was determined according to the formula: Maximum HR = 220-age. Beat-to-beat interval data were collected with the EliteHRV app and filtered using a Butterworth filter to minimize high frequency art


220-70 = 150    220-60 = 160.




nature  npj parkinson's disease  articles  article

Article

Open access

Published: 09 February 2024

Intense exercise increases dopamine transporter and neuromelanin concentrations in the substantia nigra in Parkinson’s disease

Bart de Laat, Jocelyn Hoye, Gelsina Stanley, Michelle Hespeler, Jennifer Ligi, Varsha Mohan, Dustin W. Wooten, Xiaomeng Zhang, Thanh D. Nguyen, Jose Key, Giulia Colonna, Yiyun Huang, Nabeel Nabulsi, Amar Patel, David Matuskey, Evan D. Morris & Sule Tinaz 

npj Parkinson's Disease volume 10, Article number: 34 (2024) Cite this article


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Abstract

Parkinson’s disease (PD) is characterized by a progressive loss of dopaminergic neurons. Exercise has been reported to slow the clinical progression of PD. We evaluated the dopaminergic system of patients with mild and early PD before and after a six-month program of intense exercise. Using 18F-FE-PE2I PET imaging, we measured dopamine transporter (DAT) availability in the striatum and substantia nigra. Using NM-MRI, we evaluated the neuromelanin content in the substantia nigra. Exercise reversed the expected decrease in DAT availability into a significant increase in both the substantia nigra and putamen. Exercise also reversed the expected decrease in neuromelanin concentration in the substantia nigra into a significant increase. These findings suggest improved functionality in the remaining dopaminergic neurons after exercise. Further research is needed to validate our findings and to pinpoint the source of any true neuromodulatory and neuroprotective effects of exercise in PD in large clinical trials.


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Introduction

Parkinson’s disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra (SN)1. A growing literature has demonstrated the benefits of exercise programs for controlling motor symptoms of PD2,3,4,5. The reported benefits vary according to the type, intensity, and duration of the exercise. Moderate-to-high-intensity exercise multiple times per week for prolonged periods (e.g., 6 months) has been shown to ameliorate the motor severity of PD in clinical trials6,7,8.


Rodent models of PD have shown that exercise-induced improvements in motor performance were accompanied by neuroprotective effects on the dopaminergic neurons in the SN9,10,11,12,13,14,15,16. These neuroprotective effects of exercise are thought to be mediated through neurotrophic, anti-inflammatory, and angiogenic factors. It has been suggested that the interplay between these factors facilitates rescuing of the dopaminergic neurons and increased signaling capacity of healthy dopaminergic neurons17,18. In humans, indirect clinical evidence suggests that exercise may be neuroprotective. Exercise studies in patients with PD support the mediator role of neurotrophic and anti-inflammatory factors in clinical improvement19,20,21. Low pro-inflammatory microglial activation has been proposed as a pathway linking physical activity to brain health based on postmortem examination of older adults without PD but with varying degrees of physical activity22. Postmortem nigral volumes and white matter integrity have been found to be positively correlated with physical activity in older adults without PD23. A positron emission tomography (PET) study using [11C]-raclopride in people with PD demonstrated that a single bout of vigorous cycling by habitual exercisers released significantly more dopamine in the caudate nucleus than the same activity performed by those who were sedentary24. These findings suggest that the benefits of exercise may be due to neuromodulatory effects, such as the preservation of the dopaminergic reserves and enhanced dopamine transmission. However, these putative effects have not been directly investigated in humans with PD in vivo.

High Intensity Exercise

High-intensity Exercise May Reverse Neurodegeneration in Parkinson’s Disease

February 23, 2024

High-intensity exercise induces brain-protective effects that have the potential to not just slow down, but possibly reverse, the neurodegeneration associated with Parkinson’s disease, a new pilot study suggests.

Prior research has shown that many forms of exercise are linked to improved symptoms of Parkinson’s disease. But there has been no evidence that hitting the gym could create changes at the brain level. Now, a small proof-of-concept study involving 10 patients showed that high-intensity aerobic exercise preserved dopamine-producing neurons, the brain cells that are most vulnerable to destruction in patients with the disease.

In fact, after six months of exercise, the neurons actually had grown healthier and produced stronger dopamine signals. Dopamine is a chemical that helps brain cells communicate with each other. The researchers published their findings in npj Parkinson’s Disease on February 9.

The medications we have available are only for symptomatic treatment. They do not change the disease course. But exercise seems to go one step beyond and protect the brain at the neuronal level.

Sule Tinaz, MD, PhD

“This is the first time imaging has been used to confirm that the biology of the brain in those suffering with Parkinson’s disease is changed by intense exercise,” says Evan D. Morris, PhD, professor of radiology and biomedical imaging at Yale School of Medicine and co-principal investigator of the paper.

What causes Parkinson’s disease?

Parkinson’s disease is a neurodegenerative disorder caused by the misfolding of alpha synuclein protein that is naturally present in our cells. The misfolded protein accumulates within neurons and damages them.

The dopamine-producing cells that are most affected reside in the part of the brain known as the substantia nigra, an area near the base of the brain. As these cells die off, the lack of dopamine creates the physical symptoms of the disease, particularly motor symptoms such as tremors and slowed movement. It’s a gradual progression, and at the time of diagnosis, typically patients have already lost over half of their dopamine-producing neurons.

“By the time patients clinically manifest the typical motor symptoms of Parkinson’s, you can assume that the neurodegenerative process actually started much earlier, maybe a decade or two,” says Sule Tinaz, MD, PhD, associate professor of neurology and co-principal investigator.

The most common available medication, levodopa, replaces the missing dopamine. While the drug is effective in alleviating motor symptoms, it does not prevent the ongoing neurodegeneration and can cause undesirable side effects with long-term use such as uncontrolled excessive movements [dyskinesia]. There is currently no cure for the disease.

Exercise plays a vital role in treating Parkinson’s disease

Exercise is an essential component of Parkinson’s disease management. In fact, some gyms offer exercise programs specifically for the condition. “I always tell patients that exercise is a part of their treatment,” says Tinaz. “The same way I prescribe medication, I also prescribe exercise.”

In Connecticut, Michelle Hespeler is the founder of Beat Parkinson’s Today, an evidence-based non-profit exercise program that offers online and in-person classes throughout the state. Hespeler was inspired to create her program after being diagnosed with the disease herself. “She took all of the elements of high-intensity interval training and combined it with the needs of people with Parkinson’s disease,” says Tinaz.

Previously, two well-designed clinical trials have shown that engaging in high-intensity exercise—in which participants reach around 80% to 85% of their age-appropriate maximum heart rate—three times a week for six months is correlated with less severe motor symptoms. “These trials suggested that exercise really is disease-modifying in a clinical sense,” says Tinaz. The Yale team used these clinical trials as a model for its new study.

Using brain imaging to study impact of high-intensity exercise

For their study, the Yale researchers recruited patients who had been diagnosed with Parkinson’s disease for less than four years. At this early stage of their disease, the patients had not yet lost all of their dopamine-producing neurons. All participants initially went through a two-week trial period to ensure they could handle the intensity of the exercise classes before enrolling.

After the trial period, the participants received their first round of brain scans. One was an MRI scan that measured the amount of neuromelanin—a dark pigment found in dopamine-producing neurons—in the substantia nigra. The second scan was a PET scan that measured dopamine transporter (DAT) availability. DAT is a protein that helps the neurons maintain proper dopamine levels.

Ten participants completed a six-month high-intensity exercise program through Hespeler’s Beat Parkinson’s Today program. Due to the COVID-19 pandemic, the classes took place online. These classes involve High Intensity Functional Intervals [HIFI] designed to keep participants’ heart rates elevated for the majority of the workout. Participants wore heart rate monitors to ensure they were reaching their target heart rates and other wearables (e.g., a Fitbit) to record their movements. After the six months, the researchers repeated the MRI and PET scans.

High-intensity exercise reverses neurodegeneration

Following the six-month program, brain imaging showed a significant increase in both the neuromelanin and DAT signals in the substantia nigra. This suggests that high-intensity exercise not only slowed down the neurodegenerative process, but also helped the dopaminergic system grow healthier.

“Where we would have ordinarily expected to see a decline in the DAT and neuromelanin signals, we saw an increase,” says Bart de Laat, PhD, associate professor adjunct in psychiatry and the study’s first author. “We had hoped to see that the neurodegeneration would not progress as quickly or stop temporarily, but instead we saw an increase in nine out of 10 people. That was remarkable.”

The study highlights the importance of including an exercise regimen as part of one’s Parkinson’s treatment plan. “The medications we have available are only for symptomatic treatment. They do not change the disease course,” says Tinaz. “But exercise seems to go one step beyond and protect the brain at the neuronal level.”

While this is an exciting finding, additional research will be needed to fully understand the neuroprotective effects of exercise. The team hopes that its work will inspire other scientists to prioritize research into exercise and its disease-modifying potential.

Parkinson’s disease is the fastest-growing neurological disease. By 2040, researchers estimate that over 12 million people worldwide will be living with the condition. The new study holds promise that exercise can help mitigate the enormous personal and economic costs the disease poses. “Exercise is accessible to everyone, is relatively cheap, and is safe [if your health care provider approves],” says Tinaz. “If it also has this neuroprotective effect with the potential to reverse the disease course, that is something to celebrate and to study.”