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Study of the effect of obesity on QT-interval among adults
Tarun Kumar1, Kamlesh Jha2, Ashok Sharan1
1Department of Physiology, Indira Gandhi Institute of Medical Sciences, Patna, Bihar, India.
Background:
Obesity affects the different organ systems of human body and has been recognized as a risk factor for the development of many diseases. Most of the cardiovascular diseases develop due to obesity which reflects alterations in either cardiac morphology or conduction defects. These abnormalities are reflected in ECG as prolongation of various intervals. Prolongation of QT-interval has been found to be associated with ventricular arrhythmia and sudden cardiac death.
Aims And Objectives:
The aim of the study was to investigate the effect of obesity on QT-interval to assess the risk of development of cardiovascular diseases in early stage.
Materials And Methods:
A cross-sectional study was conducted on 80 cases and 80 controls, which included adults of 18-40 years age groups from both sexes. The cases were obese [body mass index (BMI) >30 kg/m2] and the controls were nonobese (BMI < 25 kg/m2). ECG of the cases and controls was recorded and their QT-intervals were calculated and analyzed with BMI by independent samples test.
Results:
We found significantly higher QT-intervals in obese group in comparison to that of nonobese group (P = 0.000).
Conclusion:
Obesity was found to be associated with prolongation of QT-interval among young obese adults. This prolongation of QT-interval duration increases the possibility of left ventricular enlargement and ventricular fibrillation. Hence the present study helps in creating awareness among obese people so that they can change their lifestyle in order to prevent the onset of the deleterious effects of obesity on their health.
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