Prescription prevalence of low dose aspirin in primary prevention in the Spanish population, trends over time and associated factors

Abstract

Background and objective: The use of low-dose acetylsalicylic acid (LD-ASA) in primary prevention is a matter of controversy, but its magnitude is unknown in Spain. The aim of the study was to estimate the proportion of patients who are prescribed LD-ASA for primary prevention and to identify their characteristics.

Methods: In a sample from the primary care database BIFAP we obtained the proportion of persons with prescriptions of LD-ASA over the period 2002-2015, excluding patients with any previous record of occlusive vascular disease, atrial fibrillation or cancer. The proportions were standardized to the Spanish population aged 40-99 years old. We identified the factors associated with the use of LD-ASA through a logistic regression and estimated its prevalence of use according to the presence of such factors.

Results: The sample included 102,850 subjects; of which 6,198 were users of LD-ASA. The standardized prevalence of prescription was 2.21% at the start of the period and 3.57% at the end, and increased with age. The factors with the strongest associations were diabetes (OR=3.26; 95%CI: 3.07-3.47), dyslipidaemia (OR=2.08; 1.96-2.21), heart failure (OR=2.02; 1.72-2.37), and hypertension (OR=1.78; 1.67-1.90). Among diabetic patients older than 70 years with hypertension and dyslipidaemia, the prevalence of LD-ASA prescription was 33.7%.

Conclusions: The prescription of LD-ASA for primary prevention in Spain over the study period was low in the general population, but high in older diabetic patients with additional risk factors. After years of controversy, it is time to realign the use of this drug in primary prevention according to recent guidelines.

Keywords: Acetylsalicylic acid; Antiagregantes; Antiplatelets; Aspirina; Low-dose aspirin; Prevención primaria; Primary prevention; Ácido acetilsalicílico.