Health Interventions for Firefighter Cardiovascular Risk Reduction

(FCRP Trial)

Not currently recruiting at 6 trial locations

Overseen By Robert Corbell

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of Arizona

Must not be taking: Antidiabetics, others

Disqualifiers: Smoking, Pregnancy, Diabetes, Cancer, others

Compensation: Varies

Number of Visits: Unknown

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to lower the risk of heart disease, cognitive issues, and other health problems in firefighters, especially those exposed to chemicals like PFAS. It will test various interventions, including blood donation (also known as blood donation therapy or phlebotomy), plasma donation (also known as blood plasma donation or plasmapheresis), zone 2 training (a moderate-intensity exercise), and intermittent fasting. Participants will be randomly assigned to one of these groups or a control group, and researchers will measure changes in health indicators over time. Firefighters who are actively serving, plan to stay on the job for at least two years, and are part of the Fire Fighter Cancer Cohort Study might be a good fit for this study. This unphased trial offers a unique opportunity to contribute to groundbreaking research that could improve firefighter health and safety.

Will I have to stop taking my current medications?

The trial protocol does not specify if you need to stop taking your current medications. However, if you are using antidiabetic medications like Semaglutide or Tirzepatide, you may be excluded from the intermittent fasting group.

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

Research shows that the treatments being studied to reduce heart risks in firefighters—blood donation, intermittent fasting, plasma donation, and Zone 2 training—are generally safe.

A study with 285 firefighters found that blood and plasma donations significantly lowered levels of PFAS, a type of chemical, in the body, suggesting a health benefit without major safety concerns. Blood donation is considered safe and is a common practice.

Intermittent fasting also appears safe. Studies indicate it can help lower heart risks, although one study linked time-restricted eating to a higher risk of heart-related death. However, this is rare, and intermittent fasting is usually well-tolerated.

Zone 2 training, involving low-intensity exercise, supports heart and lung health while reducing the risk of injury. This type of exercise is considered safe and beneficial for overall heart health.

Overall, these methods are well-tolerated with no major safety issues reported. Participants can feel reassured about their safety in the study. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about this trial because it explores innovative lifestyle interventions to reduce cardiovascular risks in firefighters. Unlike traditional treatments that often focus on medication, this trial investigates methods like intermittent fasting, blood and plasma donation, and Zone 2 training, which is a low-intensity exercise that enhances fat metabolism. These approaches are unique as they could offer non-pharmacological alternatives to managing heart health, potentially improving outcomes through simple adjustments in daily habits. By focusing on lifestyle changes, the trial aims to identify practical, sustainable ways to support the cardiovascular health of firefighters, who face unique occupational stressors.

What evidence suggests that this trial's treatments could be effective for reducing firefighter cardiovascular risks?

Research has shown that donating blood and plasma, treatments studied in this trial, can help lower PFAS levels in the body. An Australian study found that plasma donation reduced PFOS levels by about 24%. Intermittent fasting, another treatment option in this trial, involves eating only during certain hours and may help lower risks for heart problems, such as high blood pressure and insulin resistance. Zone 2 training, also tested in this trial, is moderate exercise that can improve endurance and reduce heart disease risks. Overall, these methods have demonstrated potential benefits for improving health related to heart risks and PFAS exposure. ^{5 6 7 8 9}

Are You a Good Fit for This Trial?

This trial is for active Arizona firefighters over 18, who plan to stay in service for the next 2 years and are part of the Fire Fighter Cancer Cohort Study. They must speak English fluently, have a BMI over 17.5 kg/m2, weigh more than 115 pounds, and be able to donate blood if needed. Smokers or those with significant health issues can't participate.

Inclusion Criteria

My BMI is over 17.5 and I weigh more than 115 pounds.

I am eligible to donate blood and blood products.

Active firefighter (including emergency medical responder and all firefighter subgroups) with either a volunteer or career status

Exclusion Criteria

Those who are pregnant, breastfeeding, or have given birth within the past year

I am under 18 years old.

Not able to fluently speak or write in English

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Initial Assessment

Participants provide an initial blood sample and urine sample to determine PFAS levels

1 week

Intervention

Participants are randomly assigned to interventions: Blood/Plasma Donation, Zone 2 Training, or Intermittent Fasting, or their respective control groups

4-12 months

Final Assessment

Participants provide a final urine sample and blood draw to assess changes in PFAS levels and other health risks

1 week

Follow-up

Participants are monitored for safety and effectiveness after the intervention

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Blood Donation
• Intermittent Fasting
• Plasma Donation
• Zone 2 Training

Trial Overview The study tests whether blood donation, plasma donation, Zone 2 Training (a type of exercise), or intermittent fasting can reduce cardiovascular disease risks and PFAS levels in firefighters. Participants will follow their assigned intervention for either four months or one year before retesting.

How Is the Trial Designed?

Group I: Plasma Donation Active Control 2 Interventions

Group II: Zone 2 Training Active Control 2 Interventions

Group III: Intermittent Fasting Active Control 2 Interventions

Group IV: Blood Donation Active Control 2 Interventions

Group V: Zone 2 Control Placebo Group 1 Intervention

Group VI: Intermittent Fasting Control Placebo Group 1 Intervention

Group VII: Blood/Plasma Control Placebo Group 1 Intervention

Who Is Running the Clinical Trial?

University of Arizona

Lead Sponsor

Trials

545

Recruited

161,000+

Arizona State University

Collaborator

Trials

311

Recruited

109,000+

Published Research Related to This Trial

The 'Feeding America's Bravest' trial is a 12-month study involving about 1000 firefighters from the Indianapolis Fire Department, aiming to improve their diet by implementing Mediterranean diet principles to reduce cardiovascular disease risk.

The trial compares a Mediterranean Diet Nutritional Intervention (MDNI) with usual care, assessing changes in diet quality, body weight, and cardiometabolic risk markers, which could lead to effective strategies for promoting healthier eating in the fire service.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Rationale and design of feeding America's bravest: Mediterranean diet-based intervention to change firefighters' eating habits and improve cardiovascular risk profiles. Sotos-Prieto, M., Cash, SB., Christophi, CA., et al.[2018]

In a study of 64 obese subjects over 12 weeks, the combination of alternate day fasting (ADF) and exercise led to a significant weight loss of 6 kg and improved body composition, including reduced fat mass and waist circumference, while retaining lean mass.

The combination group also showed significant improvements in lipid profiles, with a decrease in LDL cholesterol and an increase in HDL cholesterol, indicating a lower risk of heart disease compared to ADF or exercise alone.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Alternate day fasting and endurance exercise combine to reduce body weight and favorably alter plasma lipids in obese humans. Bhutani, S., Klempel, MC., Kroeger, CM., et al.[2013]

Alternate-day fasting (ADF) is a safe and well-tolerated weight loss method, with 93% of participants completing the 8-week study without adverse effects.

While ADF and a standard caloric restriction diet produced similar weight loss results after 8 weeks, ADF showed more favorable changes in body composition, particularly in fat and lean mass, during the follow-up period.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A randomized pilot study comparing zero-calorie alternate-day fasting to daily caloric restriction in adults with obesity. Catenacci, VA., Pan, Z., Ostendorf, D., et al.[2019]

A meta-analysis of seven randomized controlled trials with 269 participants found that alternate-day fasting (ADF) significantly reduced weight and body mass index compared to control groups, indicating its effectiveness for weight loss.

Participants following ADF also showed improvements in several health markers, including lower total cholesterol, triglycerides, and blood pressure, suggesting that ADF may enhance overall health and reduce disease risk.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Health Effects of Alternate-Day Fasting in Adults: A Systematic Review and Meta-Analysis. Cui, Y., Cai, T., Zhou, Z., et al.[2020]

A 28-day carbohydrate-restricted diet (CRD) significantly reduced body fat and blood pressure in professional firefighters, indicating improvements in cardiometabolic health.

The CRD also enhanced physical performance, as evidenced by improved run times and pull-up repetitions, without negatively affecting high-intensity exercise capabilities.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A 28-Day Carbohydrate-Restricted Diet Improves Markers of Cardiometabolic Health and Performance in Professional Firefighters. Waldman, HS., Smith, JW., Lamberth, J., et al.[2020]

In an 8-week study with 59 obese participants, alternate day fasting (ADF) led to a significant weight loss of 4.2%, while only a small percentage reported mild adverse effects like constipation and dizziness.

ADF was associated with improvements in eating disorder symptoms, including a decrease in depression and binge eating, suggesting that it may have beneficial effects on body image and eating behaviors.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety of alternate day fasting and effect on disordered eating behaviors. Hoddy, KK., Kroeger, CM., Trepanowski, JF., et al.[2018]

In a 10-week study involving 16 obese adults, alternate-day fasting (ADF) led to significant reductions in body weight (5.7 kg) and waist circumference (4.0 cm), along with a decrease in fat mass (5.4 kg), indicating its efficacy in improving body composition.

ADF also improved cardiovascular risk factors by increasing beneficial adiponectin levels by 30% and reducing harmful LDL cholesterol and triglycerides by 25% and 32%, respectively, suggesting a protective effect against coronary heart disease.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Improvements in coronary heart disease risk indicators by alternate-day fasting involve adipose tissue modulations. Bhutani, S., Klempel, MC., Berger, RA., et al.[2015]

In a study involving 13 firefighters over an 8-week period, time-restricted feeding (TRF) significantly reduced the stress response, as indicated by lower salivary cortisol levels after a simulated firegrounds test.

TRF also led to decreased levels of inflammatory markers IL-6 and IL-1β, suggesting potential cardiometabolic benefits for firefighters who are at higher risk for cardiovascular disease.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Time Restricted Feeding Reduces Inflammation and Cortisol Response to a Firegrounds Test in Professional Firefighters. McAllister, MJ., Gonzalez, AE., Waldman, HS.[2021]

A 12-month study involving 485 US firefighters showed that those who participated in a Mediterranean diet intervention significantly improved their dietary habits, with an increase in their modified Mediterranean diet score by 2.67 points at 12 months compared to the control group.

Despite the positive changes in diet, the intervention did not lead to statistically significant improvements in cardiometabolic risk factors after one year, indicating that while dietary adherence improved, it may not have immediately impacted health outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of a Nutrition Intervention on Mediterranean Diet Adherence Among Firefighters: A Cluster Randomized Clinical Trial. Hershey, MS., Chang, CR., Sotos-Prieto, M., et al.[2023]

In a 12-month study involving 34 obese participants, those who lost 5% or more of their body weight on alternate-day fasting (ADF) reported feeling fuller and less hungry, indicating improved satiety.

Successful weight losers on ADF also increased their dietary protein intake from 15% to 20% of their total calories and showed better adherence to calorie goals on fasting days, suggesting effective behavioral changes associated with this diet.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Eating behavior traits of successful weight losers during 12 months of alternate-day fasting: An exploratory analysis of a randomized controlled trial. Kroeger, CM., Trepanowski, JF., Klempel, MC., et al.[2020]

Modified alternate-day fasting (ADF) led to significant weight loss (5.6 kg) and reduced body fat percentage in 16 obese adults over 8 weeks, demonstrating its efficacy as a weight management strategy.

ADF also improved cardiovascular health indicators, with notable reductions in total cholesterol, LDL cholesterol, and triglycerides, suggesting it may lower the risk of coronary artery disease.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Short-term modified alternate-day fasting: a novel dietary strategy for weight loss and cardioprotection in obese adults. Varady, KA., Bhutani, S., Church, EC., et al.[2023]

In a study of 32 non-obese individuals over 12 weeks, alternate day fasting (ADF) led to a significant weight loss of 5.2 kg (6.5%) and a reduction in fat mass without affecting fat-free mass, indicating its efficacy for weight management.

ADF also improved cardiovascular risk factors, as evidenced by decreased triacylglycerol levels, increased LDL particle size, and changes in adipokine levels, suggesting potential cardio-protective benefits in normal weight and overweight adults.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Alternate day fasting for weight loss in normal weight and overweight subjects: a randomized controlled trial. Varady, KA., Bhutani, S., Klempel, MC., et al.[2021]

A 7-week time-restricted feeding (TRF) intervention improved ventilatory threshold in professional firefighters, suggesting potential benefits for endurance performance.

While TRF did not negatively impact muscular strength, endurance, or power, it did lead to a decrease in body fat, indicating a positive effect on overall fitness without compromising performance.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Impact of Time Restricted Feeding on Fitness Variables in Professional Resistance Trained Firefighters. Gonzalez, AE., Waldman, HS., Abel, MG., et al.[2021]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC12044307/

Interventions to Reduce Serum Per- and Poly-Fluoroalkyl ... A randomized clinical trial in Australian firefighters found that routine blood and plasma donation for 1 year led to decreased serum PFAS ...

2. ffccs.org ffccs.org/intervention-to-reduce-risks

Interventions to Reduce Firefighter Cancer and ... Evaluate the effectiveness of interventions in lowering cardiovascular risk and improving the overall health and wellness of firefighters. Anticipated Impact.

3. azregents.edu azregents.edu/sites/default/files/public/rgos/trif_proposal_reducefirefightercancer_proof1.pdf

interventions to reduce firefighter cancer and Arizona firefighters are requesting a study to test the effectiveness of blood or plasma donation to lower their PFAS levels, based on a single ...

4. fcrp.arizona.edu fcrp.arizona.edu/about-study

About the Study | Firefighter Collaborative Research Project An Australian study completed in 2023 demonstrated the effectiveness of regular blood or plasma donation over 12 months in lowering PFAS levels. ... reduction of ...

5. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/35606245/

Cardiovascular Benefits for Blood Donors? A Systematic ... Of those, a majority of 9 studies reported a protective effect of blood donation, while 5 studies found no effects on cardiovascular risk factors. Results on ...

6. ahajournals.org ahajournals.org/doi/10.1161/CIRCULATIONAHA.121.056119

Studies Detail Heart Risks for Firefighters | Circulation The study is the latest in a small but growing body of evidence that identifies risk factors associated with heart-related deaths among firefighters.

7. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC8994130/

Effect of Plasma and Blood Donations on Levels of ... In this randomized clinical trial of 285 firefighters, both blood and plasma donations resulted in significantly lower PFAS levels than observation alone.

8. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC3710100/

Extreme sacrifice: sudden cardiac death in the US Fire Service The leading cause of line-of-duty mortality is sudden cardiac death, which accounts for approximately 45% of all firefighter duty-related fatalities.

9. ahajournals.org ahajournals.org/doi/10.1161/circulationaha.117.027018

Firefighting and the Heart | Circulation Fire-suppression activities markedly increase the risk of CVD events among firefighters: 10- to >100-fold greater risk compared with nonemergency fire ...