Introduction: New antidiabetic drugs have simplified treatment regimens in patients with type-2 diabetes (T2D). More importantly, they have proven to reduce cardiovascular risk by lowering insulin-resistance, blood pressure and body weight, in addition to avoiding inappropriate insulin therapy, responsible for hypoglycemic episodes and weight gain. In this context, accurate assessment of the metabolic status of T2D patients becomes essential. The C-peptide assay is a simple but often overlooked test that can provide a fundamental contribution to the correct disease classification and optimal therapeutic management of diabetic patients.
Clinical Case: We report the case of a 72-year-old patient, treated with insulin for 26 years after a diagnosis of type-1 diabetes (T1D), resulting in inadequate glycemia control and a severe evolution of cardiovascular complications. After an accurate evaluation of the clinical history, phenotype and laboratory data, including the determination of C-peptide serum levels, a diagnosis was made of T2D not T1D. Considering the patient’s very high cardiovascular risk and dysmetabolic profile, insulin therapy was discontinued and more appropriate therapy with dulaglutide and metformin was instituted. These overall therapeutic modifications yielded remarkable clinical advantages in terms of the glycometabolic profile, weight reduction, abdominal circumference and body mass index decrease, as well as a better quality of life, with complete resolution of the dangerous hypoglycemic episodes.
Conclusion: In the era of new cardioprotective antidiabetic drugs, we believe the importance of the C-peptide assay should be re-evaluated in order to avoid misdiagnosis and to improve the therapeutic approach to T2D.

Keywords: diabetes, metabolic syndrome, hypoglycemia, obesity, dulaglutide, quality of life


中文翻译：

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当胰岛素的不当使用是危险的：C-肽测定在心脏保护性抗糖尿病药物时代的效用

简介：新型抗糖尿病药物简化了 2 型糖尿病 (T2D) 患者的治疗方案。更重要的是，它们已被证明可以通过降低胰岛素抵抗、血压和体重来降低心血管风险，此外还可以避免导致低血糖发作和体重增加的不当胰岛素治疗。在这种情况下，准确评估 T2D 患者的代谢状态变得至关重要。C 肽测定是一种简单但经常被忽视的测试，它可以为糖尿病患者的正确疾病分类和最佳治疗管理提供根本性的贡献。
临床案例：我们报告了一名 72 岁患者的病例，该患者在诊断为 1 型糖尿病 (T1D) 后接受了 26 年的胰岛素治疗，导致血糖控制不足和心血管并发症的严重演变。在对临床病史、表型和实验室数据（包括 C 肽血清水平的测定）进行准确评估后，诊断为 T2D 而不是 T1D。考虑到患者的心血管风险非常高和代谢异常，因此停止了胰岛素治疗，并开始使用度拉鲁肽和二甲双胍进行更合适的治疗。这些整体治疗改进在糖代谢特征、体重减轻、腹围和体重指数降低以及更好的生活质量方面产生了显着的临床优势，
结论：在新的心脏保护性抗糖尿病药物时代，我们认为应重新评估 C 肽测定的重要性，以避免误诊并改善 T2D 的治疗方法。

关键词：糖尿病，代谢综合征，低血糖，肥胖，度拉鲁肽，生活质量