Phenotypic characteristics of patients with type 2 diabetes mellitus and coronary artery disease

Abstract

The aim – to evaluate the phenotypic characteristics of patients with type 2 diabetes mellitus (T2DM) with and without coronary artery disease (CAD), identify key features that may have prognostic significance, and assess their impact on the progression of these diseases. 
Materials and methods. We examined 246 patients with type 2 diabetes mellitus (T2DM), with and without coronary artery disease (CAD). All participants underwent anthropometric measurements, blood pressure assessment, and physical examination. Laboratory testing included fasting plasma glucose, glycated hemoglobin (HbA1c), C-peptide, total cholesterol, triglycerides, low- and high-density lipoprotein cholesterol (LDL-C, HDL-C), aspartate aminotransferase (AST), alanine aminotransferase (ALT), serum creatinine, hematological parameters, and albuminuria. The estimated glomerular filtration rate (eGFR) was calculated. CAD was diagnosed using the Bruce protocol treadmill test and confirmed by coronary angiography. Chronic kidney disease (CKD), diabetic neuropathy (DN), and heart failure (HF) were diagnosed according to relevant clinical guidelines. Data on T2DM, hypertension, history of myocardial infarction, percutaneous coronary intervention (PCI), and coronary artery bypass grafting (CABG) were obtained from medical records, including discharge summaries and clinical reports. Socioeconomic information was collected through questionnaires, covering family history of T2DM, smoking status, sleep quality, place of residence (urban or rural), and dietary habits. Statistical analysis was performed using IBM SPSS Statistics Version 20.0.0.2. Given the age difference between groups, age was included as a covariate. Statistical significance between groups was assessed using ANCOVA (Univariate Tests). 
Results and discussion. Patients with T2DM and concomitant CAD were significantly older than those without CAD (p<0.05). The leukocyte count and serum creatinine levels were significantly higher in patients with CAD (p<0.05). The prevalence of CKD among patients without CAD was 24 %, whereas in those with CAD it was significantly higher – 42 % (p<0.05). Heart failure of NYHA functional class II was more frequently observed in the CAD group (48 % vs. 16 % in the non-CAD group, p<0.05). The prevalence of peripheral neuropathy was also significantly higher in patients with T2DM and CAD (76 %) compared to those without CAD (55 %) (p<0.05). Analysis of socioeconomic status revealed that parental history of T2DM was slightly more common among patients without CAD (15 % vs. 11 %), and the maternal history of diabetes was significantly more prevalent in this group (25 % vs. 14 %, p<0.05). A significantly higher proportion of patients with T2DM and CAD reported parental exposure to famine (45 % for fathers and 46 % for mothers, p<0.05). The proportion of patients living in urban areas was significantly lower in the CAD group (50 %) compared to the non-CAD group (70 %) (p<0.05). According to our findings, patients with T2DM and CAD reported poorer sleep quality compared to those without CAD.
Conclusions. The prevalence of CKD is significantly higher in patients with T2DM and concomitant CAD, suggesting an association between ischemic heart disease and the progression of renal damage. Elevated leukocyte counts in CAD patients indicate the presence of systemic inflammation, a key mechanism in the development of cardiovascular and renal complications. The significantly higher incidence of NYHA class II heart failure in patients with T2DM and CAD reflects more pronounced cardiovascular impairment, particularly myocardial ischemic damage and cardiac remodeling. Patients with T2DM and CAD also reported significantly poorer sleep quality, which may adversely affect overall health, increasing the risk of cardiovascular events and worsening metabolic control.