Development and Internal Validation of a Four-Predictor Nomogram for In-Stent Restenosis After Drug-Eluting Stent Implantation in Patients With Overweight/Obesity.

BACKGROUND: In-stent restenosis (ISR) after drug-eluting stent (DES) implantation remains clinically relevant in patients with elevated body mass index (BMI). This study aimed to develop and internally validate a simple nomogram for ISR risk after DES in patients with overweight/obesity.

AIMS: To develop and internally validate a simple nomogram for predicting in-stent restenosis (ISR) after drug-eluting stent (DES) implantation in patients with overweight or obesity.

METHODS: A single-center retrospective cohort (2018-2023) of adults with BMI ≥ 25 kg/m² receiving first DES was analyzed. ISR was defined as ≥ 50% diameter stenosis within the stent or within 5 mm of its edges on follow-up angiography. Patients were randomly split 70/30 into training and validation cohorts. Four clinically prespecified predictors-smoking, diabetes, total stent length, and stent diameter-were entered into multivariable logistic regression to derive a nomogram. Performance was evaluated by AUC, calibration plots with Hosmer-Lemeshow testing, bootstrapping, and decision curve analysis.

RESULTS: A total of 468 high BMI patients were included, among whom 49 experienced ISR. Multivariate logistic regression analysis revealed smoking, diabetes, stent total length, and stent diameter as factors associated with ISR occurrence. The Nomogram model demonstrated strong predictive performance in both the training and validation sets, with C-index values of 0.753 and 0.729, respectively. Calibration curves and decision curve analysis further confirmed the reliability and clinical utility of the model.

CONCLUSION: A four-variable nomogram provides pragmatic ISR risk stratification after DES in patients with overweight/obesity, supporting individualized follow-up and secondary prevention. External validation and prospective evaluation are warranted.