Enteric Coating as a Factor in Aspirin Resistance

NCT00531362 | Completed

• 1 other identifier: RCSI1
• Study Type: observational
• Target: 250
• Locations: 1 country
• Sites: 1

Brief Summary

Aspirin is an essential drug for the treatment of cardiovascular disease. The standard dose is 75mg per day (much lower than that for inflammation or fever). One of the side-effects of aspirin is a gastric ulcer which can be fatal. To prevent this it is common to use enteric-coated aspirin. This passes through the stomach intact and dissolves in the intestines. This prevents high levels of drug forming in the stomach reducing ulcer formation. Recently there is evidence of high levels of aspirin resistance, ie, patients who appear not to achieve the maximum benefit from aspirin. Clinical studies have shown a significant increase in mortality among these patients. A recent study that we performed showed that enteric-coated aspirin is not as effective as plain aspirin. This was especially noticeable in heavier volunteers. In fact it appeared that enteric-coated aspirin only delivers 50mg aspirin instead of the full 75 mg. For volunteers resistant to enteric-coated aspirin simply switching them to plain aspirin solved the problem. We propose to recruit patients on 75 mg enteric aspirin and test them for evidence of poor response to aspirin. Poor responders will then be given 75mg plain aspirin and tested for their response. Those that fail to respond will then receive 150 mg aspirin. If the results of the healthy volunteer study are replicated this would provide a very cheap and effective solution to a serious problem.

Conditions

Cardiovascular Disease

Keywords

Atherosclerosis; Aspirin; Resistance,; Acute coronary syndromes

Study Arms (1)

Patients

All patients (acute or stable) presenting to a cardiovascular clinic and on aspirin.

Drug: Plain aspirin

Interventions

Plain aspirin DRUG

Plain aspirin 75 mg or 150 mg

Patients

Eligibility Criteria

• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients attending the cardiac outpatients clinic or the cat lab of Beaumont hospital, Dublin, Ireland

You may qualify if:

• Stable or unstable coronary artery disease
• On aspirin

You may not qualify if:

• Inability to give informed consent

Sponsors & Collaborators

• Royal College of Surgeons, Ireland: lead
• Irish Heart Foundation: collaborator

Study Sites (1)

Beaumont Hospital

Dublin, Ireland

Location

Related Publications (1)

• Cox D, Maree AO, Dooley M, Conroy R, Byrne MF, Fitzgerald DJ. Effect of enteric coating on antiplatelet activity of low-dose aspirin in healthy volunteers. Stroke. 2006 Aug;37(8):2153-8. doi: 10.1161/01.STR.0000231683.43347.ec. Epub 2006 Jun 22.

  PMID: 16794200 BACKGROUND

Related Links

• Irish Heart Foundation, study sponsor website

Biospecimen

Retention: SAMPLES WITHOUT DNA

Serum samples will be collected and stored for later analysis

MeSH Terms

Conditions

Cardiovascular Diseases; Atherosclerosis; Acute Coronary Syndrome

Condition Hierarchy (Ancestors)

Arteriosclerosis; Arterial Occlusive Diseases; Vascular Diseases; Myocardial Ischemia; Heart Diseases

Study Officials

• Dermot Cox, PhD

  Royal College of Surgeons

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER

Study Record Dates

• First Submitted: September 17, 2007
• First Posted: September 18, 2007
• Study Start: September 1, 2007
• Primary Completion: December 1, 2008
• Study Completion: December 1, 2008
• Last Updated: September 29, 2009

Record last verified: 2009-09

Locations

IE (1)