Statin but not aspirin treatment is associated with reduced cardiovascular risk in patients with diabetes without obstructive coronary artery disease: a cohort study from the Western Denmark Heart Registry.

AIMS

Patients with diabetes and no obstructive coronary artery disease (CAD) as assessed by coronary angiography (CAG) are frequently treated with aspirin and statins. We examined the effectiveness of aspirin and statin treatment on cardiovascular and bleeding incidence in patients with diabetes and absent obstructive CAD.

METHODS AND RESULTS

The study included patients with diabetes and absent obstructive CAD as assessed by CAG from 2003 to 2016 in Western Denmark. We stratified patients by aspirin and statin treatment within 6 months after CAG in two separate analyses. Outcomes were MACE (major adverse cardiovascular events, a composite of myocardial infarction, ischaemic stroke, and death) and bleeding (aspirin only). To account for confounding, we used propensity score-based weights to estimate the inverse probability of treatment-weighted hazard ratios (HRIPTW). We included 4124 patients with diabetes but without CAD as assessed by CAG, among whom 2474 (60%) received aspirin and 2916 (71%) received statin treatment within 6 months following CAG. Median follow-up was 4.9 years. Aspirin did not reduce 10-year MACE [21.3% vs. 21.8%, HRIPTW 1.01, 95% confidence interval (CI) 0.82-1.25], all-cause death (HRIPTW 0.96, 95% CI 0.74-1.23), or bleeding (HRIPTW 0.95, 95% CI 0.73-1.23), compared to those not receiving aspirin treatment. Statin treatment reduced MACE (25% vs. 37%, HRIPTW 0.58, 95% CI 0.48-0.70) compared to those not receiving statin treatment.

CONCLUSION

Among patients with diabetes and no obstructive CAD, aspirin neither reduced MACE nor increased bleeding. In contrast, statin treatment was associated with a major reduction in risk of MACE.