Clinical trial NCT00738491: Effects of Ambient Air Pollution Exposure in Patients With Stable Angina Pectoris During Normal Daily Activities
Official title: Effects of Ambient Air Pollution Exposure in Patients With Stable Angina Pectoris During Normal Daily Activities
Study type: OBSERVATIONAL
Overall status: TERMINATED
Conditions: Angina Pectoris
Coronary Heart Disease
Keywords: Angina pectoris
Exercise capacity
Myocardial ischaemia
Air pollution
Lead sponsor: University of Edinburgh
Sponsor class: OTHER
Collaborators: name: Imperial College London
First posted: 2008-08-20
Enrollment: 1
Sex: ALL
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_CROSSOVER
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Patients with stable angina pectoris and documented coronary artery disease

Brief summary: The purpose of this study is to identify whether exposure to ambient levels of air pollution during normal daily activities has a functional impact on patients with coronary heart disease

Detailed description: Exposure to air pollution has been shown in epidemiological studies to be closely linked to cardiovascular morbidity and mortality. The exact components of air pollution that underlie the cardiovascular effects are not yet known, but combustion-derived particulate matter is suspected to be the major cause. In controlled exposure studies, we have recently demonstrated that exposure to diesel exhaust causes increased myocardial ischaemia with exercise in patients with asymptomatic coronary artery disease. The mechanism behind this effect is not yet understood, but we have shown that diesel exhaust exposure causes an acute impairment of two important and highly relevant aspects of vascular tone: vasomotor tone and endogenous fibrinolysis. In this study we propose to investigate the effects of exposure to ambient levels of air pollution on patients with stable, symptomatic angina pectoris, during their daily lives.

Eligibility criteria: Inclusion Criteria:

* Documented coronary artery disease
* Symptoms of stable angina pectoris
* Positive BRUCE exercise stress test between 3 and 13 minutes

Exclusion Criteria:

* History of arrhythmia
* Severe 3 vessel coronary disease or left main stem stenosis that has not been revascularised
* Resting conduction abnormality
* Digoxin therapy
* Uncontrolled hypertension
* Renal or hepatic failure
* Unstable symptoms or acute coronary syndrome within 3 months

Primary outcomes:
measure: Symptoms of angina pectoris - assessed by symptom diary and reliever medication usage
timeFrame: Throughout study period
Secondary outcomes:
measure: Myocardial ischaemic burden - assessed using 12-lead continuous Holter ECG monitoring
timeFrame: Throughout study period
measure: Time to 1mm ST segment depression during standard BRUCE exercise stress testing
timeFrame: At the end of the study period
measure: Total exercise capacity - measured using GPS tracking of activity completed
timeFrame: Throughout study period
measure: Exercise capacity - determined by standard BRUCE exercise stress testing
timeFrame: Immediately after study period
measure: Ambulatory blood pressure
timeFrame: Throughout study period
measure: Biochemical evidence of myocardial ischaemia - highly sensitive troponin, ischaemically modified albumin and fatty acid binding protein
timeFrame: Before and after study period
Other outcomes:
Locations:
city: Edinburgh
country: United Kingdom
facility: University of Edinburgh
state: Midlothian
city: London
country: United Kingdom
facility: Imperial College
Study officials:
affiliation: University of Edinburgh
name: Jeremy P Langrish, MB BCh
role: PRINCIPAL_INVESTIGATOR
References:
citation: McCreanor J, Cullinan P, Nieuwenhuijsen MJ, Stewart-Evans J, Malliarou E, Jarup L, Harrington R, Svartengren M, Han IK, Ohman-Strickland P, Chung KF, Zhang J. Respiratory effects of exposure to diesel traffic in persons with asthma. N Engl J Med. 2007 Dec 6;357(23):2348-58. doi: 10.1056/NEJMoa071535.
citation: Mills NL, Tornqvist H, Gonzalez MC, Vink E, Robinson SD, Soderberg S, Boon NA, Donaldson K, Sandstrom T, Blomberg A, Newby DE. Ischemic and thrombotic effects of dilute diesel-exhaust inhalation in men with coronary heart disease. N Engl J Med. 2007 Sep 13;357(11):1075-82. doi: 10.1056/NEJMoa066314.
citation: Tornqvist H, Mills NL, Gonzalez M, Miller MR, Robinson SD, Megson IL, Macnee W, Donaldson K, Soderberg S, Newby DE, Sandstrom T, Blomberg A. Persistent endothelial dysfunction in humans after diesel exhaust inhalation. Am J Respir Crit Care Med. 2007 Aug 15;176(4):395-400. doi: 10.1164/rccm.200606-872OC. Epub 2007 Apr 19.
citation: Mills NL, Tornqvist H, Robinson SD, Gonzalez M, Darnley K, MacNee W, Boon NA, Donaldson K, Blomberg A, Sandstrom T, Newby DE. Diesel exhaust inhalation causes vascular dysfunction and impaired endogenous fibrinolysis. Circulation. 2005 Dec 20;112(25):3930-6. doi: 10.1161/CIRCULATIONAHA.105.588962.