A Study of QTc Prolongation as a Screening Tool for Cardiovascular Disease in Type 2 Diabetes Patients of Karad, India

Abstract

BACKGROUND The occurrence of QT interval prolongation is higher in subjects with type 2 diabetes mellitus (T2DM). Duration of QT interval corrected (QTc) for heart rate is independently related with severity of cardiovascular diseases in diabetics. This study was proposed to assess the QTc prolongation as a diagnostic tool for cardiovascular disease in T2DM patients. METHODS This study included 100 diabetic patients admitted in wards of a tertiary care center. A thorough clinical examination was carried out for all the patients. Patients were investigated for the fasting blood glucose level, glycated haemoglobin (HbA1c), lipid profile & electrocardiogram (ECG). Data was represented as percentage. Mean and standard deviation (SD) of quantitative variables were tabulated, t test was used for correlation and receiver operating characteristic (ROC) curve was used for evaluating area under curve. P < 0.05 was considered statistically significant. RESULTS Male preponderance was observed. All the study subjects had a prolonged period of diabetes with various metabolic complications. The area under the curve estimation of QTc > 400 ms with respect to HbA1c and duration of diabetes showed significant correlation between longer duration of diabetes and raised HbA1c associated with raised QTc interval (P < 0.05). CONCLUSIONS Diagnosis of prolonged QTc interval could be utilized for estimating cardiovascular risk in diabetes patients. It can be easily assessed on ECG besides being a noninvasive investigation which is also affordable in evaluating the cardiovascular risk in T2DM patients. KEY WORDS Blood Glucose, Cardiovascular Diseases, Electrocardiography, Glycated Haemoglobin A, Long QT Syndrome, Type 2 Diabetes Mellitus