Background: While the importance of diabetes mellitus (DM) in the pathogenesis of coronary artery disease (CAD) has been proven in many studies, there is few data about the prevalence of DM in young patients with ST-elevation myocardial infarction (STEMI). Aim of the present study was to analyse the prevalence of DM and pre-DM in young patients with STEMI, its association to other cardiovascular risk factors and its impact on severity of CAD.

Methods: All patients ≤45 yrs. old, admitted with STEMI into a German Heart Centre treated with primary coronary intervention (PCI) between 2006 and 2019 entered analysis. For a subset of patients (2015-19), the definition of diabetes could be extended, since HbA1c-levels at admission were available.

Results: Of 776 young STEMI-patients 88 (11%) had a DM while 688 (89%) did not. In the subgroup-analysis with available HbA1c-levels a newly diagnosed DM (HbA1c ≥6.5%) was evident in 8% and a newly diagnosed preDM (HbA1c 5.7-6.4%) in 24% of the study-cohort (Table 1). This combined prevalence of 44% of any type of dysglycaemia was more than 3x higher than the expected prevalence for this age group according to literature (Figure 1). 

Diabetics were more likely to be obese (BMI ≥30 kg/m², OR 2.4, 95%CI 1.4-4.0) and especially very obese (BMI ≥40 kg/m², OR 5.1, 95%CI 2.1-12.2) and, as a trend, more likely to be female (OR 1.7, 95% CI 0.93-3.1, p=0.08). Diabetes in the young was associated with a higher likelihood of subacute STEMI (OR 2.2, 95% CI 1.1-4.5) and with more advanced CAD (OR 1.6, 95% CI 1.0-2.6) compared to non-diabetics. Conclusions:While the overall prevalence of known DM in young STEMI-patients was only 11%, when including HbA1c-criteria into the definition the rate of detected dysglycaemias was 44%. This high rate of DM and preDM in young STEMI patients emphasizes the importance of early screenings, especially in patients with obesity, since diabetes is associated with premature development of complex CAD already in this young patient group.

Table 1 Distribution of dysglycaemias in the subgroup analysis 2015-2019

Figure 1: Comparison of dysglycaemia in young patients with STEMI vs. general population (BSR = Bremen STEMI Registry, IDF = International Diabetes Federation 2019)