Abstract 4364542: Aspirin Use for Primary Prevention of Cardiovascular Events in High Risk Patients with Diabetes: A Propensity Matched Analysis

Background: Aspirin (ASA) use for primary prevention of ASCVD events is no longer regularly recommended. However, little is known about how ASA adherence influences cardiovascular outcomes in diabetic patients based on their glycemic control and ASCVD risk. We investigated the impact of ASA use and adherence frequency on ASCVD outcomes in patients with diabetes, stratified by hemoglobin A1c (HbA1c). Methods: Using an EHR generated primary prevention registry across a large healthcare network (>400+ sites), ASA use (no use, <30% of the time, 30% - < 70% of the time and ≥ 70% of the time) was assessed in patients with moderate or high 10-year ASCVD risk score. Propensity score matching (PSM) (1:2 ratio) was performed to balance baseline characteristics between ASA users and non-users. Cumulative Incidence Function (CIF) and Kaplan-Meier (KM) analyses were conducted on the PSM cohort to compare outcomes between ASA treatment groups. Multivariable-adjusted hazard ratios (HR) were calculated using Cox proportional hazards models. Subgroup analyses evaluated effect modification by HbA1c categories (6.5–7%, 7–9%, >9%) Results: In 11,681patients (61.6 ± 9.79 years, 46.24% female), 88.6% were ASA and 53.15% were statin users at anytime during 10-year follow up. Cumulative incidence of MI (42.4% vs 61.2%), Stroke (14.5% vs 24.8%), 10-year all-cause mortality (33.0% vs 50.7%), all p<0.001 was significantly lower in PSM ASA group compared to No ASA group. [ Table 1 ]. Any ASA use was associated with significantly lower hazards of MI and ischemic stroke compared to no ASA use with greater benefit observed in the high frequency use group (HR MI : 0.54 [0.50–0.58]; HR STROKE : 0.47 [0.41–0.53]; both p<0.001) [ Table 2 ]. Subgroup analysis by HbA1c showed consistent benefit of ASA (with statin use) across glycemic strata, though the magnitude of benefit declined with worse glycemic control. [ Table 3 ]. Mortality reduction was also more pronounced in better-controlled groups. Conclusion: Aspirin use is associated with significant reductions in MI, stroke, and mortality among high-risk patients with diabetes, with greater frequency conferring more benefit.