Endocrine Abstracts

Introduction: People with T1D have greater cardiovascular mortality and morbidity compared to healthy individuals (1). Since the advent of continuous glucose monitoring (CGM), new data (“glucometrics”) have been introduced such as time in range (TIR: 70 –180 mg/dl) and time in tight range (TITR: 70 –140 mg/dl), changing the standard of care in diabetes management (2). We examined an association between TIR and macrovascular complications (MACE).

Methods: Data from adults with T1D who were using CGM (MDI or pump) were analyzed over a 5-year period. Macrovascular complications were present if one of the following was documented: coronary heart disease (ischemic heart damage detected in cardiologic work-up or symptomatic AMI), the need for a revascularization procedure, cerebrovascular events including TIA (transient ischemic attack) and stroke (CVA) and the presence of peripheral arterial disease.

Results: We included 147 adults with T1D (51.7% were male) with a mean age of 46 } 16 years, mean diabetes duration of 28 ± 14 years. Mean BMI was 24.9 ± 3.9 kg/m². This cohort had a median HbA1c of 7.5 (6.9–8.1) %, a TIR of 49 ± 15% and TITR of 34 ± 11%. At the five-year time point, HbA1c decreased to 7.1 (6.5–7.6, P <0.001) %, TIR increased to 63 ± 16% (P <0.001) and TITR to 41 ± 14% (P = 0.005). 15 acute coronary events were recorded, 6 of which were symptomatic and 9 asymptomatic. 3 people died of non-cardiovascular causes. No cardiovascular mortality was reported. 6 cerebrovascular events occurred (3 TIAs,3 CVAs) and 14 people had peripheral arterial disease of whom one underwent surgical intervention. Patients who experienced MACE were more likely to report a familial history (P = 0.016), had a higher chance of taking antihypertensive medication at start of the study (34.8 vs 65.2%, P = 0.003) or at 60 months (39.5 vs 63.6%, P = 0.036) or lipid lowering medication at start (30.4 vs 65.2%, P = 0.004). No statistically significant differences between groups were reported concerning HbA1c or TIR. Family history of a major cardiovascular event and use of antihypertensive medication at start of the study were independently associated with macrovascular complications as identified using logistic regression analysis. This was the case in the model using HbA1c as well as in the model using TIR.

Conclusion: In this small study cohort, no association was found between TIR and macrovascular complications. Family history of cardiovascular events and use of antihypertensive medication were found to be independently associated with the presence of MACE.

References: 1. Colom C, Rull A, Sanchez-Quesada JL, P érez A. Cardiovascular Disease in Type 1 Diabetes Mellitus: Epidemiology and Management of Cardiovascular Risk. J Clin Med. 2021;10(8). 2. De Meulemeester J, Charleer S, Visser MM, De Block C, Mathieu C, Gillard P. The association of chronic complications with time in tight range and time in range in people with type 1 diabetes: a retrospective cross-sectional real-world study. Diabetologia. 2024;67(8):1527-35.

Keywords: Type 1 diabetes, continuous glucose monitoring, macrovascular complications, time in range