CO2 Exposure for Cognitive Impairment

Overseen By Alicia Legard

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: Rutgers, The State University of New Jersey

Must not be taking: Beta-blockers, Cns depressants

Disqualifiers: Cardiovascular disease, Diabetes, Pregnancy, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 2

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores how carbon dioxide (CO2) affects thinking and memory. Participants will experience varying levels of CO2 exposure to assess its impact on cognitive function. The trial is open to individuals vaccinated against COVID-19 who weigh at least 110 pounds. Those with asthma, cardiovascular issues, or on certain medications affecting cognition are not eligible. As an unphased trial, it offers a unique opportunity to contribute to understanding the cognitive effects of CO2 exposure.

Will I have to stop taking my current medications?

The trial requires that you stop taking medications for anxiety disorders, panic attacks, and those that may affect cognition, such as beta-blockers and CNS depressants. If you use sedating cold/allergy medications, marijuana, or alcohol, you must stop these for a specified period before participating.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research shows that exposure to carbon dioxide (CO2) can affect cognitive function. For example, one study found that moderate CO2 levels led to lower scores on cognitive tests. Another study found that even CO2 levels below 500 parts per million (ppm) could impair clear thinking. However, these effects appeared only at certain CO2 levels.

While reports indicate changes in cognitive ability, studies have not widely reported serious safety issues or adverse side effects. The trial under consideration involves CO2 levels higher than typical indoor levels, but not extremely high. Current research suggests that while some cognitive effects might occur, extreme or dangerous reactions are not expected. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about the carbon dioxide (CO2) exposure protocol for cognitive impairment because it explores a novel approach to brain health. Unlike traditional treatments that often rely on medication to enhance cognitive function, this trial investigates how controlled CO2 exposure may affect cognitive processes. The unique aspect of this study is its focus on environmental modulation, using different CO2 concentrations to potentially stimulate brain activity. By understanding the impact of CO2 exposure, researchers hope to uncover new, non-invasive strategies to support cognitive health, which could pave the way for innovative treatments that are quite different from the current pharmaceutical options.

What evidence suggests that CO2 exposure is effective for understanding cognitive impairment?

Research has shown that inhaling carbon dioxide (CO2) can affect cognitive function. This trial will expose participants to varying CO2 levels to assess the impact on thinking ability. One group will first encounter low CO2 levels (600 ppm) and then high CO2 levels (2500 ppm), while another group will experience the reverse order. Previous studies have indicated that performance begins to decline at CO2 levels of 1,000 parts per million (ppm). Another study found that complex tasks became more difficult when CO2 levels were below 5,000 ppm. These findings suggest that higher CO2 levels can impair decision-making and clarity of thought. ^{1 2 3 4 5}

Who Is on the Research Team?

Howard Kipen, MD

Principal Investigator

Professor

Are You a Good Fit for This Trial?

This trial is for individuals who have been vaccinated against COVID-19 and weigh at least 110 pounds. It's not suitable for those with colorblindness, diabetes on insulin therapy, pregnant women, hearing impairments, recent asthma attacks, anxiety disorders or panic attacks treated with medication, cognitive-affecting medications like beta-blockers and CNS depressants, or a history of cardiovascular disease.

Inclusion Criteria

You have received a COVID-19 vaccine in the past.

You weigh at least 110 pounds.

Exclusion Criteria

Colorblindness

You are pregnant.

You have had an asthma attack within the past five years.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Exposure Sessions

Participants undergo two 2.5-hour exposure sessions with CO2 concentrations of either 600 ppm or 2500 ppm, at least one week apart. Neurobehavioral assessments and blood samples are collected.

2 weeks

2 visits (in-person)

Follow-up

Participants are monitored for safety and effectiveness after exposure sessions

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Carbon Dioxide (CO2)

Trial Overview The study aims to understand how breathing in different levels of carbon dioxide (CO2) affects thinking abilities. Participants will be exposed to two CO2 concentrations: one similar to normal air (600 ppm) and another much higher (2500 ppm).

How Is the Trial Designed?

Group I: High CO2 Exposure first, then low CO2 exposure second. Experimental Treatment 2 Interventions

At the first study visit the subject is exposed to 2500 ppm CO2 for 2.5 hours and at the second study visit the subject is exposed to 600 ppm CO2 for 2.5 hours.

Group II: Low CO2 Exposure first, then high CO2 exposure second. Placebo Group 2 Interventions

At the first study visit the subject is exposed to 600 ppm CO2 for 2.5 hours and at the second study visit the subject is exposed to 2500 ppm CO2 for 2.5 hours.

Who Is Running the Clinical Trial?

Rutgers, The State University of New Jersey

Lead Sponsor

Trials

471

Recruited

81,700+

Published Research Related to This Trial

Mild cognitive impairment (MCI) affects 5% to 29% of the population, with significant variability in prevalence due to differences in case identification and sampling methods, highlighting the need for standardized definitions.

Key risk factors for MCI include age, education, race, hypertension, brain lesions, depression, and the presence of the APOE-4 allele, suggesting potential targets for future interventions to prevent progression to dementia.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Mild cognitive impairment: an epidemiological perspective. Ritchie, K.[2022]

Exposure to air pollutants, particularly particulate matter (PM2.5 and PM10), is linked to cognitive disorders in the elderly, highlighting a significant public health concern.

Further research is needed, including large longitudinal studies and toxicological investigations, to better understand the physiological mechanisms behind the relationship between air pollution and cognitive impairment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Association between air pollution and cognitive function in the elderly]. Wang, JN., Wang, Q., Li, TT., et al.[2018]

The systematic review analyzed 1,551 abstracts and found that out of 10 articles, 8 met the criteria, indicating a potential association between historical air pollution exposure and poorer cognitive function in older adults.

While some studies suggested a link between air pollution and cognitive decline, the evidence was mixed for new cases of cognitive impairment, highlighting the need for more detailed and longitudinal research in this area.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Is air pollution associated with increased risk of cognitive decline? A systematic review. Peters, R., Peters, J., Booth, A., et al.[2022]

In a study of 49,705 adults over nearly a decade, higher exposure to fine particulate matter (PM2.5) was linked to slower cognitive processing speeds, indicating a direct negative impact on cognitive function.

The research found that while lung function played a minor role in mediating the effects of PM2.5 on cognition, the majority of the cognitive impairment was due to direct exposure, highlighting the significant health risks posed by fine particles.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Long-term exposure to fine particulate matter, lung function and cognitive performance: A prospective Dutch cohort study on the underlying routes. Aretz, B., Janssen, F., Vonk, JM., et al.[2021]

Using the recirculation (RC) setting in vehicles can effectively reduce exposure to roadway pollutants, but it can also lead to high levels of carbon dioxide (CO2) accumulation, especially during longer trips with multiple occupants.

While most average-duration commutes (about 26 minutes) for one or two occupants do not exceed the 2500 ppm CO2 threshold linked to cognitive effects, it's recommended to mix in outside air during longer trips or with more passengers to prevent reaching harmful CO2 levels.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Carbon dioxide accumulation inside vehicles: The effect of ventilation and driving conditions. Hudda, N., Fruin, SA.[2018]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC4892924/

Associations of Cognitive Function Scores with Carbon ... Results: On average, cognitive scores were 61% higher on the Green building day and 101% higher on the two Green+ building days than on the Conventional ...

2. sciencedirect.com sciencedirect.com/science/article/pii/S036013232300358X

Short-term exposure to indoor carbon dioxide and ... The results indicated that CO 2 exposure below 5000 ppm impacted human cognitive performance, with complex cognitive tasks being more significantly affected ...

3. nature.com nature.com/articles/s41526-019-0071-6

Effects of acute exposures to carbon dioxide on decision ... Both the SMS and Cognition demonstrated a slight performance decrease at 1200 ppm relative to 600 ppm. Our results are unique and comport with ...

4. clinicaltrials.gov clinicaltrials.gov/study/NCT05292378

Carbon Dioxide (CO2) and Cognitive Impairment Most clinical studies have one primary outcome measure, but some have more than one. ... The main reason for the clinical trial. The types of primary purpose are: ...

5. newscenter.lbl.gov newscenter.lbl.gov/2012/10/17/elevated-indoor-carbon-dioxide-impairs-decision-making-performance/

Elevated Indoor Carbon Dioxide Impairs Decision-Making ... On nine scales of decision-making performance, test subjects showed significant reductions on six of the scales at CO2 levels of 1,000 parts per ...