Background: Glycated haemoglobin (HbA1c) is a well-established biomarker for diabetes diagnosis and management and is linked to risk of cardiovascular death. However, among adults without cardiovascular disease (CVD) and diabetes, the value of HbA1c in predicting distinct signatures of myocardial ageing has not been explored. Methods: Subjects, from among older adults without CVD, underwent comprehensive cardiovascular and metabolic assessment. Transthoracic echocardiography measured left ventricular structure and function. Longitudinal left atrial (LA) strain comprising reservoir strain (Ɛs), conduit strain (Ɛe) and booster strain (Ɛa) and their corresponding peak strain rates (SRs, SRe, SRa) were measured using cardiac magnetic resonance (CMR). Blood sampling for biomarkers and cardiovascular examinations were performed. Results: 247 subjects (mean age 71 years, 44.1% female, mean HbA1c 6.0%) were included. HbA1c was significantly associated with E/A ratio (p < 0.0001), conduit strain (Ɛe) (p < 0.0001), conduit strain rate SRe (p < 0.0001), and conduit strain rate to booster strain rate SRe:SRa ratio (p < 0.0001). Multivariate models adjusting for clinical variables such as body mass index, blood pressure, heart rate, diabetes mellitus, smoking, and associated cardiac parameters, demonstrated a persistent independent association. Each unit increase in HbA1c was associated with lower E/A ratio, lower Ɛe, higher SRe and lower SRe:SRa ratio. These associations remained significant after diabetic subjects were excluded. Conclusion: Distinct associations were found between HbA1c and myocardial functions of interest in the ageing heart. HbA1c may be useful biomarker for stratifying risks associated with myocardial ageing, independent of diabetes status.

Trial registration: ClinicalTrials.gov Identifier: NCT02791139.

背景： 糖化血红蛋白 （HbA1c） 是糖尿病诊断和管理的公认生物标志物，与心血管死亡风险有关。然而，在没有心血管疾病 （CVD） 和糖尿病的成年人中，HbA1c 在预测心肌衰老的不同特征方面的价值尚未得到探索。方法： 来自无 CVD 的老年人的受试者接受了全面的心血管和代谢评估。经胸超声心动图测量左心室结构和功能。使用心脏磁共振 （CMR） 测量由储库应变 （Ɛs）、导管应变 （Ɛe） 和增强应变 （Ɛa） 组成的纵向左心房 （LA） 应变及其相应的峰值应变率 （SRs、SRe、SRa）。进行生物标志物和心血管检查的血液采样。结果： 纳入 247 例受试者 （平均年龄 71 岁，44.1% 为女性，平均 HbA1c 为 6.0%）。HbA1c 与 E/A 比 （p < 0.0001）、导管应变 （Ɛe） （p < 0.0001）、导管应变率 SRe （p < 0.0001） 和导管应变率与增强应变率 SRe：SRa 比率 （p < 0.0001） 显著相关。根据体重指数、血压、心率、糖尿病、吸烟和相关心脏参数等临床变量进行调整的多变量模型显示出持续的独立关联。HbA1c 每增加一个单位，E/A 比值较低，Ɛe 较低，SRe 较高，SRe：SRa 比值较低。在排除糖尿病受试者后，这些关联仍然显着。结论： 发现 HbA1c 与老年心脏感兴趣的心肌功能之间存在明显的关联。 HbA1c 可能是与心肌衰老相关的风险分层的有用生物标志物，与糖尿病状态无关。

试用注册：ClinicalTrials.gov 标识符：NCT02791139。