Prevalence and characteristics of low-dose acetylsalicylic acid intake in the German population: insights from the German National Cohort (NAKO)

Background Atherosclerotic cardiovascular diseases (ASCVD) remain a leading cause of morbidity and mortality worldwide. While low-dose antiplatelet therapy with acetylsalicylic acid (ASA) is recommended for secondary prevention, its use in primary prevention is not supported. We investigated the prevalence, characteristics and determinants of ASA intake in primary and non-intake in secondary prevention using population-based data. Methods Data from 203,413 participants of the German National Cohort Study (NAKO) were analysed. Regular ASA intake was defined as daily intake for at least one week. Medication data were obtained through standardized interviews and coded using the Anatomical Therapeutic Chemical (ATC) system. Sociodemographic factors, comorbidities, and concomitant cardiovascular medication were assessed. Determinants of ASA intake in primary and non-intake secondary prevention were identified using multivariable logistic regression. Results 11,020 (5.4%) reported regular ASA use. Among users, 59.6% had ASCVD, whereas 40.4% used ASA without ASCVD, corresponding to 2.1% of the total cohort. Among participants with ASCVD, 53.3% reported ASA use and 66.1% any form of antiplatelet or anticoagulant therapy, leaving 43.9% untreated. In primary prevention the strongest determinants of ASA use were hypertension and congestive heart failure, whereas female sex was associated with lower use (OR 0.62, 95% CI 0.58, 0.67). In secondary prevention, ASA non-use was most strongly associated with female sex (OR 2.64, 95% 2.41, 2.88). Conclusion Only half of individuals with ASCVD reported regular ASA intake, suggesting possible underuse of ASA in secondary prevention. ASA use in primary prevention was reported by 2.3%. Female sex consistently predicted lower ASA use.