Aspirin and Clopidogrel Resistance Study

University Hospital, Basel, Switzerland82 enrolled

Overview

Resistance to antiplatelet drugs (aspirin, clopidogrel) is a recognized phenomenon with a prevalence from 17% to 35%. Resistance as detected by in vitro tests such as Multiple Electrode Aggregometry (MEA) has been shown to predict clinical therapy failure. Resistance can be caused by clinical, cellular and pharmacogenetic factors. Non compliance is suspected to be an important contributing factor. In this study, compliance will be assured with an electronical compliance monitoring system. Factors to non response will be identified to find plausible explanations when in vitro platelet aggregation inhibition is insufficient despite assured compliance. This study will help to disclose the relationship between compliance, biomarker and clinical outcome as well as to quantify the impact of non compliance to the resistance phenomenon as measured by MEA.

Study Type

OBSERVATIONAL

Enrollment

Conditions

Drug Resistance

Eligibility

Sex: ALLMin age: 45 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Patients prescribed aspirin and/or clopidogrel for both including both cardiovascular and cerebrovascular indications seeing their general practitioner in or nearby Olten/SO for any medical purpose * Patients with oral and written German language ability Exclusion Criteria: * Patients living in care homes * Patients not preparing their drugs on their own (e.g. outpatient medical assistance through "spitex"). * Patients with acute cardiac symptoms

Locations (1)

Outcomes

Primary Outcomes

Platelet aggregation, initial and after one week under compliance monitoring.

Time frame: 1 week

Secondary Outcomes

Data on compliance (measured by electronic compliance monitoring, Morisky MMAS-8 and BMQ Score)

Time frame: 1 week

Frequency of contributing factors to non-response in responders compared to non-responders (pharmacogenetics, clinical factors and drug-drug interactions)

Time frame: 4 weeks