In patients undergoing PCI and treated with clopidogrel, we explored whether the combination of blood glucose status and ABCB1 C3435T genetic variation could help identify those at higher risk of developing major adverse cardiovascular events (MACE). A total of 117 patients were included in the analysis, among whom 52 experienced MACE. Genotyping of CYP2C19 and ABCB1 C3435T was performed using fluorescence-based in situ hybridization. Clinical data, including baseline characteristics, fasting glucose levels, and outcome events, were systematically collected. Logistic regression models were used to identify variables associated with MACE in patients receiving clopidogrel after PCI. When comparing patients with and without MACE, several baseline characteristics showed significant imbalance, including demographic factors (such as sex and age), metabolic and clinical history (diabetes, hypertension, alcohol use), fasting glucose levels, and genotype–glycemia combinations of ABCB1 C3435T. All of these differences reached statistical significance (P < 0.05). In the multivariate model, four variables independently contributed to MACE risk. The ABCB1 C3435T variant showed a strong association with adverse outcomes (OR = 5.584, P = 0.024). Increasing age was also associated with a higher risk (OR = 1.073 per unit increase, P = 0.014), as was a history of hypertension (OR = 3.144, P = 0.020) and diabetes mellitus (OR = 3.731, P = 0.030). In patients younger than 75 years, the pattern of associations changed slightly: hypertension remained a significant predictor of MACE (OR = 3.151, P = 0.021), while individuals carrying the ABCB1 CC genotype with normal glycemic status showed a significantly reduced risk, suggesting a protective effect in this subgroup (OR = 0.147, P = 0.023). The ABCB1 C3435T polymorphism appears to independently contribute to the risk of major adverse cardiovascular events in patients receiving clopidogrel after PCI. In contrast, the combination of the CC genotype with normal glycemic status may be associated with a reduced risk of MACE, particularly in individuals younger than 75 years.
