# Diabetes-related ten-year outcomes after percutaneous coronary intervention of in-stent restenosis

## TL;DR

This study finds that diabetics, especially those needing insulin, have worse heart outcomes ten years after a specific type of heart procedure compared to non-diabetics.

## Contribution

The study provides new long-term data on outcomes after PCI for in-stent restenosis specifically in diabetic patients.

## Key findings

- Diabetic patients had higher rates of cardiac death and heart attacks after 10 years compared to non-diabetics.
- Insulin-dependent diabetics had worse outcomes than non-insulin-dependent diabetics.
- Repeat heart procedures were more common in diabetic patients.

## Abstract

Limited data is available for long-term outcomes after percutaneous coronary intervention (PCI) of coronary drug-eluting stent (DES) in-stent restenosis (ISR) in diabetics.

Thus, the aim of this observational, retrospective study was to close this lack of evidence.

Between January 2007 and February 2021, a total of 3511 patients with 5497 ISR lesions were treated at two large-volume centers in Munich, Germany, of which 1242 (35.4%) were diabetics. Endpoints of interest were the rates of cardiac death, repeat revascularization, and myocardial infarction (MI). Survival was analyzed using the Kaplan–Meier method. Differences between the groups were tested with the log-rank test. Conventional multivariable analysis with adjustment for relevant variables was performed.

After 10 years, the rates of cardiac death were 42.8% for diabetics and 32.8% for nondiabetics (HRadj 1.55 [95% CI, 1.31–1.81], p < 0.001). MI occurred in 15.9% of diabetics and in 9.7% of non-diabetics (HRadj 1.70 [95% CI, 1.36–2.11], p < 0.001). The rates of repeat revascularization of target lesion (HRadj 1.17 [95% CI, 1.02–1.34], p = 0.028), target vessel, and nontarget vessel were significantly higher in diabetics as compared to nondiabetics. No statistically relevant difference was found regarding the rate of stent thrombosis. Compared to non-insulin-dependent diabetics, insulin-dependent diabetics show higher rates of cardiac death and MI, but comparable revascularization rates in both diabetic groups.

In the long term, the rates of cardiac death, MI, and repeat revascularization after PCI of DES-ISR are significantly higher in diabetics, particularly in insulin-dependent diabetics, than in nondiabetics.

The online version contains supplementary material available at 10.1007/s00392-025-02782-6.