NCT05869747

Brief Summary

The goal of this research is to test interventions to reduce firefighter cardiovascular, cognitive, and overall disease risks, including but not limited to risks associated with Per- and Polyfluorinated Substances (PFAS) exposure. Approximately 1,500 - 2,000 firefighters will be enrolled in the Fire Fighter Cancer Cohort Study (FFCCS). Among these individuals, those that express interest will then be screened for eligibility for the Firefighter Collaborative Research Project (FCRP) using information they provided for the Fire Fighter Cancer Cohort Study. Firefighters enrolled in the study will provide an initial blood sample and urine sample. The blood sample will be analyzed to determine the participant's PFAS levels. Based upon serum PFAS levels and responses from the screening survey, eligible participants will be randomly assigned into one of the following interventions: 1. Blood Donation, or Plasma Donation or Blood/Plasma Control Group; 2. Zone 2 Training or Zone 2 Control; 3. Intermittent Fasting or Intermittent Fasting Control. Individuals participating in the blood donation, plasma donation or blood/plasma control group would donate blood every 12 weeks, plasma every 6 weeks, or not donate blood or plasma. Participants in this intervention arm would continue this for a 12-month period. Individuals in the zone 2 training, zone 2 training control, intermittent fasting or intermittent fasting control group would participate in their intervention or control for a 4-month period. After 4 to 12 months participating in an intervention or control group, participants will be asked to provide a final urine sample and blood draw to determine if and to what degree their PFAS levels or other cardiovascular disease and other health risks have changed.

Trial Health

55
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
1,500

participants targeted

Target at P75+ for not_applicable

Timeline
Completed

Started Jun 2023

Typical duration for not_applicable

Geographic Reach
1 country

7 active sites

Status
active not recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

April 24, 2023

Completed
28 days until next milestone

First Posted

Study publicly available on registry

May 22, 2023

Completed
1 month until next milestone

Study Start

First participant enrolled

June 22, 2023

Completed
2.5 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 31, 2025

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

December 31, 2025

Completed
Last Updated

June 4, 2025

Status Verified

January 1, 2025

Enrollment Period

2.5 years

First QC Date

April 24, 2023

Last Update Submit

May 29, 2025

Conditions

Keywords

Firefighters

Outcome Measures

Primary Outcomes (2)

  • Change in concentration of PFAS levels in serum

    PFAS levels are per- and polyfluoroalkyl substance levels measured from a biological sample

    12 months

  • Change in epigenetic age

    Epigenetic age is a mathematically derived age estimators that are based on combinations of methylation values that change with age at specific CpGs in the genome.

    4 months

Study Arms (7)

Blood Donation

ACTIVE COMPARATOR
Behavioral: Blood DonationBehavioral: Surveys

Plasma Donation

ACTIVE COMPARATOR
Behavioral: Plasma DonationBehavioral: Surveys

Blood/Plasma Control

PLACEBO COMPARATOR
Behavioral: Surveys

Zone 2 Training

ACTIVE COMPARATOR
Behavioral: Zone 2 TrainingBehavioral: Surveys

Intermittent Fasting

ACTIVE COMPARATOR
Behavioral: Intermittent FastingBehavioral: Surveys

Zone 2 Control

PLACEBO COMPARATOR
Behavioral: Surveys

Intermittent Fasting Control

PLACEBO COMPARATOR
Behavioral: Surveys

Interventions

Blood DonationBEHAVIORAL

Participants asked to donate whole blood at a donation facility from a list provided by the study.

Blood Donation
Plasma DonationBEHAVIORAL

Participants asked to donate plasma at a donation facility from a list provided by the study.

Plasma Donation
Zone 2 TrainingBEHAVIORAL

Participants asked to work out in their custom Zone 2 heart range 4 times a week for 45 to 60 minutes.

Zone 2 Training

Participants asked to engage in an intermittent fasting routine of a 16 hour fast followed by an 8 hour eating period at least 4 times a week.

Intermittent Fasting
SurveysBEHAVIORAL

Participants were asked to complete surveys throughout the study to monitor intervention progress and to collect baseline and end-of-study data.

Blood DonationBlood/Plasma ControlIntermittent FastingIntermittent Fasting ControlPlasma DonationZone 2 ControlZone 2 Training

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Active firefighter (including emergency medical responder and all firefighter subgroups) with either a volunteer or career status
  • Individual plans to remain in active service with their current agency for the next 2 years (not planning to retire or resign)
  • years of age and older
  • Fluently speak and write in English
  • All sexes, races, and ethnicities
  • Enrolled in the Fire Fighter Cancer Cohort Study (FFCCS) prior to enrolling in the Firefighter Collaborative Research Project (FCRP)
  • Complete a signed and dated informed consent document that indicates the participant has been informed of all aspects of the study prior to enrollment
  • Agree to avoid participating in FCRP intervention activities outside of their assigned intervention group for the duration of the study
  • Able to comply with scheduled visits, laboratory tests and other study procedures
  • BMI of 17.5 kg/m2 or greater and be greater than 115 pounds
  • Must also be eligible to donate blood and blood-based products if randomized into the blood or plasmapheresis intervention groups

You may not qualify if:

  • Not able to fluently speak or write in English
  • Less than 18 years of age
  • Currently a tobacco smoker or vaping (e.g. \>2 cigarettes or cigars, or incidents of vaping in the past month)
  • Those with planned travel or extended leave (e.g. \>6 weeks) that would prevent their ability to participate in other interventions
  • Those who are pregnant, breastfeeding, or have given birth within the past year
  • Those with a history or diagnosis of any significant metabolic, hematologic, pulmonary, cardiovascular, gastrointestinal, neurological, immune, hepatic, renal, urological disorders, severe injury or cancer that, in the opinion of the investigator, would potentially put the candidate at risk.
  • Those with PFOS levels \<5 ng/ml
  • Those with any medical contraindication (medical condition or medication) to blood donation
  • Those that donated blood or plasma in the past three months
  • Those knowing they have a condition indicative of levels of hemoglobin, hematocrit, red blood cells, or iron below the lower limit of normal levels
  • Those with a history or diagnosis of diabetes, hypoglycemia thyroid disease, and/or an eating disorder
  • Those who recently participated in intermittent fasting or Time Restricted Eating
  • Those that recently used antidiabetic medication such as Semaglutide (sold as Ozempic, Wegovy, and Rybelsus) or Tirzepatide (sold as Mounjaro) for the treatment of type 2 diabetes or for weight loss will also be excluded from this group.
  • Use of drugs that might affect intermittent fasting or eating behaviors
  • Those outside of the state of Arizona
  • +3 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (7)

Gilbert Fire & Rescue Department

Gilbert, Arizona, 85295, United States

Location

Green Valley Fire

Green Valley, Arizona, 85622, United States

Location

Tucson Fire Department Headquarters

Tucson, Arizona, 85701, United States

Location

Tucson Fire Department Station 9

Tucson, Arizona, 85711, United States

Location

University of Arizona

Tucson, Arizona, 85719, United States

Location

Northwest Fire District

Tucson, Arizona, 85743, United States

Location

Drexel Heights Fire

Tucson, Arizona, 85746, United States

Location

Related Publications (1)

  • Conner R, Porter C, Lutrick K, Beitel SC, Hollister J, Healy O, Kern KJ, Wardenaar F, Gulotta JJ, Jack K, Huentelman M, Burgess JL, Furlong M. Interventions to Reduce Serum Per- and Poly-Fluoroalkyl Substances Levels, Improve Cardiovascular Risk Profiles, and Improve Epigenetic Age Acceleration in US Firefighters: Protocol for Randomized Controlled Trial. JMIR Res Protoc. 2025 Apr 16;14:e67120. doi: 10.2196/67120.

MeSH Terms

Interventions

Blood DonationSurveys and Questionnaires

Intervention Hierarchy (Ancestors)

Tissue and Organ ProcurementHealth ServicesHealth Care Facilities Workforce and ServicesData CollectionEpidemiologic MethodsInvestigative TechniquesHealth Care Evaluation MechanismsQuality of Health CareHealth Care Quality, Access, and EvaluationPublic HealthEnvironment and Public Health

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
SINGLE
Who Masked
PARTICIPANT
Purpose
OTHER
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

April 24, 2023

First Posted

May 22, 2023

Study Start

June 22, 2023

Primary Completion

December 31, 2025

Study Completion

December 31, 2025

Last Updated

June 4, 2025

Record last verified: 2025-01

Data Sharing

IPD Sharing
Will not share

Locations