A hidden danger for heart patients: Diabetes can quietly double the risk of complications after stent surgery. Many people think that once a stent is implanted, the heart is safely on the road to recovery. But recent findings from Sweden’s Karolinska Institutet paint a much more concerning picture—especially for those living with diabetes. And this is the part most people miss: not all cases of diabetes carry the same level of risk.
According to a large-scale study published in Diabetes Care (https://doi.org/10.2337/dc25-1624), individuals with diabetes are significantly more likely to experience complications after receiving coronary stents. The research analyzed data from more than 160,000 patients treated between 2010 and 2020 with drug-eluting stents—tiny mesh tubes that not only hold arteries open but also gradually release medication to prevent the vessel from clogging again. The participants were grouped into three categories: those with type 1 diabetes, those with type 2 diabetes, and those without diabetes.
The results were eye-opening. People with type 1 diabetes faced over twice the risk of experiencing stent-related complications compared to non-diabetic patients. Those with type 2 diabetes also showed elevated risk, though to a lesser degree. These complications included stent thrombosis (blood clots forming inside the stent) and restenosis (the artery narrowing again within the stent). “People with diabetes—especially those with type 1—are at a much higher risk for stent complications,” explained Irene Santos-Pardo, the study’s first author and a researcher at Karolinska Institutet’s Department of Clinical Science and Education at Södersjukhuset. “This means we need to think carefully about how we monitor and treat this group after surgery.”
But here’s where it gets even more alarming: the danger peaks soon after the procedure. The first month following stent implantation shows the highest rate of complications—9.27 per 100 person-years among type 1 diabetes patients, compared with 4.34 among those without diabetes. Although the risk declines after six months, it still remains elevated for diabetic patients. “Our findings highlight the importance of adapting both treatment and follow-up care for individuals with diabetes receiving stents,” added Thomas Nyström, senior author and professor at the same department.
The project was a collaboration between Karolinska Institutet and Spain’s Germans Trias i Pujol Institute in Barcelona, supported by the Swedish Heart-Lung Foundation and Region Stockholm. The researchers declared no conflicts of interest.
This study challenges the long-held assumption that stent outcomes are roughly similar across all heart patients. If people with diabetes—especially type 1—face dramatically higher risks, should hospitals adjust their standard treatment plans? And how might personalized follow-ups prevent these complications before they occur? Share your thoughts below—should cardiac care for diabetic patients be fundamentally restructured?
