Cardiovascular risk and missed opportunities for treatment in patients with type 2 diabetes presenting with very premature coronary artery disease
Authors: Vikulova D , Brown C , Theberge E , Mancini G.B.J , Pimstone S.N , Brunham L.R 
Published: November 2020

Abstract

Background
Type 2 diabetes mellitus (T2D) is a major cardiovascular risk factor (CVRF), and comprehensive risk factor management reduces the incidence of cardiovascular events.

Purpose
To assess 1) prevalence of T2D among patients presenting with newly diagnosed very premature coronary artery disease (CAD) and its impact on CVRFs and extent of atherosclerosis; 2) effectiveness of glucose and lipid control in T2D patients before presentation with CAD.

Methods
We studied patients with angiographically proven CAD with stenosis of ≥50% who presented at the age of ≤50 years for males and ≤55 years for females. Diabetes was defined as fasting plasma glucose ≥7 mmol/L, haemoglobin (Hb)A1C ≥6.5% or diagnosis or treatment of T2D before or at presentation with CAD. CVRFs were defined as dyslipidemia, hypertension, obesity, current smoking, and family history of premature cardiovascular disease (CVD). Values are reported as mean (±SD), median (interquartile range) or percentages.

Results
From 417 premature CAD patients, 112 (26.9%) had T2D at the time of presentation with CAD. In 27 (24.1%) patients, T2D was newly diagnosed at presentation with CAD. Age of diagnosis of T2D was 41.3 (±6.9) years old. Patients with T2D had higher prevalence of dyslipidemia (83.0% vs 63.3%, p&lt;0.001), hypertension (65.2% vs 40.3%, p&lt;0.001), and obesity (56.3% vs 34.8%, p&lt;0.001), higher cumulative number of CVRFs per person (2.8 (±1.2) vs 2.0 (±1.2), p&lt;0.001) and less favourable lipid profiles, with higher levels of triglycerides (3.3 (2.1–4.7) vs 2.3 (1.5–3.4) mmol/L, p=0.001) and lower HDL-cholesterol (0.9 (±0.3) vs 1.1 (±0.3) mmol/L). Prevalence of smoking (32.1% vs 24.9%, p=0.14) and family history of premature CVD (43.8% vs 39.7%, p=0.45), levels of LDL-cholesterol (3.7 (±1.4) vs 3.8 (±1.2) mmol/L, p=0.23) and lipoprotein(a) (206 (99–819) vs 200 (99–700) mg/L, p=0.57) were not significantly different between groups. T2D patients had a greater prevalence of 3-vessel disease (35.7% vs. 22.2%, p=0.006) and were less likely to receive revascularization (70.5% vs 83.9%, p=0.002).
Prior to presentation with CAD, 31 (27.7%) of T2D patients received insulin, 42 (37.5%) received oral hypoglycemic drugs, and 12 (10.7%) received no pharmacological treatment for diabetes. Only 23 (27.1%) of them achieved HbA1C ≤7% at the time of presentation with CAD (Figure 1). Among all T2D patients, 35 (31.3%) received treatment with statins and 16 (14.3%) reached guideline-recommended lipid targets of LDL cholesterol ≤2 mmol/L and/or non-HDL cholesterol ≤2.6 mmol/L.

Conclusion
Among patients with very premature CAD, T2D was common, was previously unrecognized in up to one quarter, and was associated with a greater burden of CVRFs and more extensive CAD at presentation. Few patients with T2D achieved guideline-recommended lipid or glucose targets. These data point to the need for improvements in screening and comprehensive CVRF treatment of T2D in order to reduce the burden of premature CAD.
Figure 1

Funding Acknowledgement
Type of funding source: Public grant(s) – National budget only. Main funding source(s): Canadian Institutes of Health Research. St. Paul's Hospital Foundation and the Vancouver General Hospital Foundation