Incidence and Influencing Factors of In‐Stent Restenosis After Percutaneous Coronary Intervention in Patients With Coronary Artery Disease: A Systematic Review and Meta‐Analysis

Percutaneous coronary intervention (PCI) is a commonly used treatment for patients with coronary artery disease (CAD), yet in-stent restenosis (ISR) remains a significant problem affecting long-term outcomes. This study systematically determined the incidence of ISR and its influencing factors in CAD patients after PCI using a meta-analytical approach. A systematic literature search was conducted in PubMed, Embase, Web of Science, and CINAHL for relevant articles published up to August 2024. Meta-analysis was performed using R Studio to estimate the pooled effect sizes for both incidence and influencing factors. Heterogeneity was assessed using I² and Q tests, and publication bias was evaluated using funnel plots and Egger's test. A total of 42 studies were included, involving 31,884 patients and 16 potential influencing factors. The meta-analysis showed that the overall estimated incidence of ISR after PCI in CAD patients was 23% (95% CI: 20%-27%, p < 0.001). The following factors were identified as significant risk factors for ISR: longer lesion length (OR = 1.07, 95% CI: 1.04-1.11), use of bare-metal stents (OR = 3.29, 95% CI: 2.30-4.71), longer stent length (OR = 1.23, 95% CI: 1.11-1.35), greater number of stents (OR = 3.51, 95% CI: 2.34-5.26), diabetes mellitus (OR = 1.59, 95% CI: 1.37-1.85), complex lesions (type B2/C) (OR = 1.44, 95% CI: 1.22-1.70), restenotic lesions (OR = 3.71, 95% CI: 2.56-5.37), bifurcation lesions (OR = 2.24, 95% CI: 1.43-3.53), smoking (OR = 1.49, 95% CI: 1.17-1.89), high red cell distribution width (OR = 1.67, 95% CI: 1.15-2.42), and high-sensitivity C-reactive protein (OR = 2.24, 95% CI: 1.03-4.89). In contrast, larger reference vessel diameter (OR = 0.56, 95% CI: 0.46-0.67) and larger minimal lumen diameter (OR = 0.55, 95% CI: 0.47-0.63) were associated with a lower risk of ISR. However, sex (OR = 1.57, 95% CI = 0.68-3.63), pre-interventional stenosis degree (OR = 1.19, 95% CI = 0.99-1.43), and low-density lipoprotein cholesterol (OR = 1.02, 95% CI = 0.98-1.06) did not significantly affect ISR after PCI. The incidence of ISR after PCI in CAD patients is high. Longer lesion length, the use of bare-metal stents, longer stent length, a greater number of stents, diabetes, lesion type B2/C, the presence of restenotic lesions and bifurcation lesions, smoking, high red cell distribution width, and high-sensitivity C-reactive protein increase the risk of ISR after PCI in CAD patients. In contrast, larger reference vessel diameter and larger minimal lumen diameter may reduce the risk of ISR.