Factors affecting over-the-counter use of aspirin in the secondary prophylaxis of cardiovascular disease.

Little is known about the contribution of over-the-counter (OTC) aspirin to cardiovascular prophylaxis. To investigate this, a two-phase cross-sectional study was carried out in nine general practices in North Staffordshire. In the first phase, all patients with cardiovascular disease (CVD) were identified from computer searches using morbidity registers and drug searches. The search also identfied the subgroup receiving prescribed prophylactic aspirin. In the second phase, a questionnaire was posted to all patients with CVD who were not on prescribed aspirin to establish their current use of OTC aspirin. Overall, 69% of the CVD group used aspirin, with 26% of aspirin being OTC. OTC aspirin use was more common in those aged under 65 years, men, and the more affluent. Also, there were significant differences in OTC aspirin use between the various practices. This study shows that a considerable amount of aspirin is used OTC in those with CVD. Its use is influenced by several factors that could be addressed when considering attempts to improve the overall uptake of aspirin.