Diabetes raises sudden cardiac death risk — even without blocked arteries

A large retrospective study out of Finland has found that diabetes significantly raises the risk of sudden cardiac death (SCD) — and that risk persists even when there's no obstructive coronary artery disease (CAD) in the picture. Analyzing over 22,000 patients who underwent coronary angiography between 2007 and 2018, researchers found that diabetic patients faced a 38% higher risk of SCD compared to those without diabetes, independent of their CAD status.

The findings also revealed that for diabetic patients who do have CAD, coronary revascularization was associated with a meaningfully lower SCD risk compared to medication alone. Meanwhile, higher A1c levels correlated with greater fatal SCD risk, pointing to glycemic control as a key lever.

Key Takeaways:

• Diabetes was associated with a 38% higher SCD risk (SHR 1.38) and a similar increase in non-sudden cardiac death risk
• Even with no obstructive CAD, diabetes still raised SCD risk by 53% (SHR 1.53)
• Revascularization in diabetic CAD patients was associated with a 23% lower SCD risk vs. medical therapy alone
• Higher-risk subgroups include patients under 70, those with type 1 diabetes, and those with poor glycemic control

Why it matters: Diabetes is already a well-known cardiovascular risk factor, but this study highlights that SCD risk in diabetic patients goes beyond blocked arteries. Clinicians may need to rethink how they stratify SCD risk in this population — factoring in age, diabetes type, and glycemic control — rather than relying solely on CAD status.