Physiological Changes in Adults With Metabolic Syndrome Exposed to Ultrafine Air Particles

NCT01475968 | Completed

• 2 other identifiers: XCON04-1677
• Study Type: interventional
• Target: 48
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to examine the acute health effects of concentrated ambient ultrafine (UF) particulate matter (PM) exposure in patients with metabolic syndrome. Without lifestyle changes or medical intervention these patients are at considerable risk for developing diabetes and cardiovascular disease. Subjects (25-70) were exposed to both UF PM and filtered air for 2hr (at least 2 week interval), physiologic endpoints were measure pre-, post-, and 20hr post-exposure. Our hypothesis is that PM exposure in this population will result in changes in vascular and endothelial response as assessed by flow-mediated dilatation of the brachial artery and various heart rate variability and blood endpoints. This study and similar studies of susceptible populations are needed to provide the EPA with information regarding the health risks associated with ambient levels of UF PM.

Conditions

Metabolic Syndrome

Outcome Measures

Primary Outcomes (1)

• Changes in Vascular Function

  1. Measurement of dilatation of the brachial artery (flow mediated and nitroglycerin mediated) 2. Measurement of vasoconstrictor/vasodialtor, pro-coagulant, or pro-inflammatory mediators into systemic circulation (by ELISA of plasma) 3. Measurement of changes in plasma levels of circulating microparticles and endothelial progenitor cells (as indicators of vascular injury or remodeling)

  change from baseline 0 hr after exposure, and change from baseline 20 hr after exposure. There will be at leat 2 weeks between the exposures

Secondary Outcomes (1)

• Changes in heart rate variability

  change from baseline 0 hr after exposure, and change from baseline 20 hr after exposure. There will be at leat 2 weeks between the exposures

Study Arms (2)

Ultrafine Air Pollution Particulate Matter

ACTIVE COMPARATOR

\<2.5 microns concentrated from outside ambient air

Other: Ultrafine Air Pollution Particulate Matter

Filtered Air

SHAM COMPARATOR

Filtered Air

Other: Filtered Air

Interventions

Ultrafine Air Pollution Particulate Matter OTHER

Ultrafine (particle diameter less than 2.5 microns) Air Pollution Particulate Matter, concentrated from the ambient air outside of the Chapel Hill EPA Human Studies Facility

Also known as: ultrafine particulate matter, concentrated ambient particulates (CAPS)

Ultrafine Air Pollution Particulate Matter

Filtered Air OTHER

Filtered Air

Also known as: clean air

Filtered Air

Eligibility Criteria

• Age: 25 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age between 25-70 years old
• Metabolic syndrome as defined by the participant having at least three of the following criteria:
• Abdominal obesity: Men waist circumference \>102 cm (\>40 in) Women waist circumference \>88 cm (\>35 in)
• Triglycerides: ≥150 mg/dL
• HDL cholesterol: Men \<40 mg/dL and Women \<50 mg/dL
• Blood pressure: ≥130/≥85 mmHg OR have a history of high blood pressure requiring medication
• Fasting glucose: ≥100 mg/dL and ≤126 mg/dL
• Normal resting electrocardiograph (ECG).

You may not qualify if:

• Current smoker or smoking history within 3 months of study (defined as more than one pack of cigarettes in the past 3 months).
• Oxygen saturation below 95% at the time of physical exam.
• Blood pressure ≥160/≥100 mmHg
• Fasting blood glucose \>126 mg/dl
• Hypersensitivity to nitroglycerin or other nitrates
• Any chronic medical condition including active pulmonary disease, cardiovascular disease (coronary artery disease, heart failure, rhythm disturbances, etc.), neurological disease, liver disease, kidney disease, muscular disease, diabetes, other endocrine disease, hematologic/lymphatic disease, immune deficiency or autoimmune disease.
• Hepatitis B carriers
• Skin diseases or sensitivity precluding the use of ECG electrodes
• Active cancer, history of cancer within the last 5 years, untreated cancer. Potential participants may have a history of mild, treated skin cancer provided the condition does not interfere with ECG electrode placement.
• No exposure will be conducted within 4 weeks of a respiratory tract infection.
• History of serve migraines
• Pregnant women or nursing mothers

Sponsors & Collaborators

• David Diaz-Sanchez: lead
• Environmental Protection Agency (EPA): collaborator

Study Sites (1)

EPA Human Studies Facility

Chapel Hill, North Carolina, 27599, United States

Location

MeSH Terms

Conditions

Metabolic Syndrome

Interventions

Particulate Matter; Environment, Controlled

Condition Hierarchy (Ancestors)

Insulin Resistance; Hyperinsulinism; Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases

Intervention Hierarchy (Ancestors)

Complex Mixtures; Environment; Environment and Public Health

Study Officials

• Robert B Devlin, PhD

  US EPA

  PRINCIPAL INVESTIGATOR

• Candice B Smith, PhD

  US EPA

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: FED
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Biologist

Study Record Dates

• First Submitted: November 14, 2011
• First Posted: November 22, 2011
• Study Start: December 1, 2004
• Primary Completion: June 1, 2011
• Study Completion: October 1, 2013
• Last Updated: November 7, 2013

Record last verified: 2013-11

Locations

US (1)