Experimental Exposure to Air Pollutants and Sympathetic Nerve Activity in Human Subjects

NCT01914783 | Unknown

• 1 other identifier: MHH-Particles EK-6142
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

The primary hypothesis of the study is that in healthy elderly subjects experimental exposure to air pollutants increases sympathetic nervous system activity compared with sham (clean air) exposure. The secondary hypothesis of the study is that combined experimental exposure to air pollutants (particles + ozone) increases sympathetic nervous system activity to a greater extent than does the exposure to particles alone.

Conditions

Cardiovascular Morbidity

Keywords

air pollution; ozone; fine particle; cytokine; chemokine; oxidative stress; inflammation; heart rate variability; autonomic nervous system; sympathetic nerve activity; plasma catecholamine

Outcome Measures

Primary Outcomes (1)

• Muscle sympathetic nerve activity (MSNA)

  Change of sympathetic vasoconstrictor nerve activity directed to skeletal muscle expressed as sympathetic bursts per minute. The primary hypothesis of the study is that in healthy elderly subjects experimental exposure to air pollutants increases sympathetic nervous system activity compared with sham (clean air) exposure.

  2.5 hours after exposure to clean air, to ultrafine particles, or to a combination of ultrafine particles and ozone

Secondary Outcomes (2)

• MSNA burst incidence

  2.5 hours after exposure to clean air, to ultrafine particles, or to a combination of ultrafine particles and ozone

• total MSNA

  2.5 hours after exposure to clean air, to ultrafine particles, or to a combination of ultrafine particles and ozone

Other Outcomes (14)

• Blood pressure

  2.5 hours after exposure to clean air, to ultrafine particles, or to a combination of ultrafine particles and ozone

• Heart rate

  2.5 hours after exposure to clean air, to ultrafine particles, or to a combination of ultrafine particles and ozone

• Cardiac output

  2.5 hours after exposure to clean air, to ultrafine particles, or to a combination of ultrafine particles and ozone

Study Arms (3)

ultrafine particles

EXPERIMENTAL

Subjects will be exposed to ultrafine particles for three hours in an exposure chamber. During that time participants will perform intermittent bicycle ergometer training. Training intensity is adjusted individually to increase ventilation to 20 l/min/m². During exposure, heart rate will be monitored continuously via ECG. Blood pressure will be measured every 15 minutes. Ultrafine elemental carbon black particles are generated using a commercially available electric spark generator. Particle number, mass, and size distribution will be monitored during exposure.

Other: ultrafine particles

ultrafine particles and ozone

ACTIVE COMPARATOR

Subjects will be exposed to ultrafine particles for three hours in an exposure chamber. During that time participants will perform intermittent bicycle ergometer training. Training intensity is adjusted individually to increase ventilation to 20 l/min/m². During exposure, heart rate will be monitored continuously via ECG. Blood pressure will be measured every 15 minutes. Ultrafine elemental carbon black particles are generated using a commercially available electric spark generator. Particle number, mass, and size distribution will be monitored during exposure.Ozone is generated from medical oxygen in order to maintain a concentration of 250 ppb.

Other: ultrafine particles and ozone

clean air

PLACEBO COMPARATOR

Subjects will be exposed to clean air for three hours in an exposure chamber controlled for temperature, humidity, and gas/particle composition. During that time they will perform intermittent bicycle ergometer training for 15 minutes alternating with 15 minutes rest. Training intensity is adjusted individually to increase ventilation to 20 l/min/m². During exposure, heart rate will be monitored continuously via ECG. The blood pressure will be measured in time intervals of 15 minutes.

Other: clean air

Interventions

ultrafine particles OTHER

exposure to ultrafine particles

ultrafine particles

ultrafine particles and ozone OTHER

exposure to ultrafine particles and ozone

ultrafine particles and ozone

clean air OTHER

Exposure to clean air.

clean air

Eligibility Criteria

• Age: 50 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Elderly man or postmenopausal woman older than 50 years of age.
• Signed written informed consent.

You may not qualify if:

• Smoker.
• Cardiovascular and/or pulmonary disease.
• Medication with relevant impact on autonomic system function, e. g. norepinephrine reuptake inhibitors. Stable medication with slight to moderate autonomic effects is tolerable.
• Subject is the investigator or any sub-investigator, research assistant, pharmacist, study coordinator, other staff or relative thereof directly involved in the conduct of the protocol.
• Mental condition rendering the subject unable to understand the nature, scope, and possible consequences of the study.
• Subject unlikely to comply with protocol, e. g. uncooperative attitude or unlikelihood of completing the study.
• Known hypersensitivity to ozone.
• History of drug or alcohol abuse. Particles Study - Protocol version: October 19, 2012 14
• Blood donation of more than 500 mL during the previous 3 months.

Sponsors & Collaborators

• Hannover Medical School: lead
• Fraunhofer-Institute of Toxicology and Experimental Medicine: collaborator

Study Sites (1)

Hannover Medical School

Hanover, 30625, Germany

RECRUITING

Related Publications (1)

• Tank J, Biller H, Heusser K, Holz O, Diedrich A, Framke T, Koch A, Grosshennig A, Koch W, Krug N, Jordan J, Hohlfeld JM. Effect of acute ozone induced airway inflammation on human sympathetic nerve traffic: a randomized, placebo controlled, crossover study. PLoS One. 2011 Apr 8;6(4):e18737. doi: 10.1371/journal.pone.0018737.

  PMID: 21494635 BACKGROUND

MeSH Terms

Conditions

Inflammation

Interventions

Particulate Matter; Ozone; Environment, Controlled

Condition Hierarchy (Ancestors)

Pathologic Processes; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Complex Mixtures; Oxygen; Gases; Inorganic Chemicals; Environment; Environment and Public Health

Central Study Contacts

Marcus May, MD

CONTACT

+49 511 532; may.marcus@mh-hannover.de

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: SUPPORTIVE CARE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor Dr. med. Jens Jordan

Study Record Dates

• First Submitted: July 30, 2013
• First Posted: August 2, 2013
• Study Start: July 1, 2013
• Primary Completion: December 1, 2015
• Study Completion: December 1, 2015
• Last Updated: August 2, 2013

Record last verified: 2013-07

Locations

DE (1)