Introduction: Hypercortisolaemia is characterised by an increased risk of cardiovascular disease (CVD), either through a direct action on the myocardium or by affecting traditional cardiovascular risk factors. The electrocardiogram (ECG) is the initial examination to assess the structural and functional characteristics of the myocardium.
Aim of the study: To investigate whether the metabolic and cardiovascular features of Cushings disease (CD) are associated with alterations in the ECG indices as a measure of cardiac abnormality.
Methods: Seventy-nine patients (61 females; age: 40.76±1.38 years) with a diagnosis of CD, retrospectively recruited, were compared with 42 healthy subjects (29 females; age: 41.76±0.84 years) with similar age and BMI. The ECG features: QT dispersion (QTcd), left (LVH) and right (RVH) ventricular hypertrophy, and systolic (SBP)/diastolic (DBP) blood pressure were assessed in both groups. In patients with CD biochemical (fasting glucose, lipids), hormonal parameters (cortisol day curve), carbohydrate abnormalities (CHA: impaired fasting glucose, impaired glucose tolerance, diabetes mellitus), CVD (angina, myocardial infarction, heart attack, arrhythmias, stroke, thromboemolic disease, acute pulmonary oedema), hypertension (HTN) presence were recorded.
Results: LVH (b=12.41, P=0.01) and RVH (b=12.33, P=0.04) were predictors of QTcd; QTcd (OR=1.08, CI=1.021.14, P=0.006) and DBP (OR=1.05, CI=1.011.10, P=0.02) were predictors of LVH; QTcd (OR=1.09, CI=1.021.17, P=0.02) and age (OR=0.88, CI=0.800.98, P=0.02) were predictors of RVH. No ECG parameter was correlated with hypercortisolaemia. In patients with CD metabolic syndrome (39%), HTN (81%), CVD (21.5%), dyslipidaemia (36.7%), CHA (40.5%), arrhythmias (1.3%) were observed. Patients had longer QTcd (P<0.001), prevalent LVH (P=0.002), RVH (P=0.05), and higher SBP and DBP (P<0.001) compared to controls. Patients without HTN, CVD were younger females (P<0.001) but still more obese (P=0.05), with longer QTcd (P<0.001), prevalent RVH (P=0.05) and higher DBP (P<0.001) compared to controls.
Conclusions: QTcd seems to be directly related to the presence of CD independently from the cardiovascular risk factors or the level of hypercortisolaemia. Since CD is associated with increased risk for CVD, ECG features might represent an easily assessed cardiovascular risk marker present early in the natural history of CD.