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The effects of body mass index on surface electrocardiograms in young adults
Javed M Nasir1, Bernard J Rubal, Samuel O Jones
1Department of Cardiology, SAMMC, San Antonio, TX, USA. javed.nasir@us.af.mil
Introduction:
While BMI is known to affect ECG measurements, these effects have not been well characterized in young adults.
Methods:
We retrospectively reviewed all ECGs performed in adults 18 to 35 years old at a single institution over a 30 year period. ECG measurements were derived electronically and stratified by WHO BMI category.
Results:
A total of 55,218 ECGs were included. Increasing BMI led to increased P wave duration and decreasing P, R, and T wave axes. Additionally, while increasing BMI led to less R wave voltage, J point elevation, and T wave amplitude in patients with a BMI ≥ 18.5 kg/m(2), there was also a decrease in the measured parameters in patients with a BMI <18.5 kg/m(2).
Discussion:
BMI had significant effects on ECG measurements. For accurate assessment of ECGs, these data should be incorporated into established nomograms. Further investigation into the effects of BMI on the ECG is warranted.
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