High anxiety in clinically healthy patients and increased QT dispersion: a meta-analysis.
BACKGROUND
Exaggerated dispersion of repolarization is likely to play a role in both the initiation and the maintenance of malignant ventricular arrhythmias. It was proposed that the inter-lead QT interval differences within a 12-lead ECG termed 'QT dispersion' might reflect regional differences in myocardial refractoriness, and that this might predict cardiac dysrhythmias.


OBJECTIVE
The study aimed to perform a meta-analysis of the relevant available publications.


METHODS
A MEDLINE search from 1990 to 2012 at PubMed (NLM) was performed. An all-fields search for index terms 'QT dispersion' and 'anxiety' was done. Case-control studies and surveys were included in the analysis provided they encompassed physically healthy subjects who had been evaluated for anxiety disorders with validated inventories. Outcome measures were either crude or heart rate-corrected QT dispersions.


RESULTS
Five studies were included in the analysis, which encompassed 580 patients with calculated mean age of 36.8 years (standard error = 5.5). The values of crude and heart rate-corrected QT dispersions across the studies were statistically significantly higher in the patients with anxiety disorders. Crude values of QT dispersion were available in 164 patients with anxiety and in 273 controls. Summarized standardized difference in the means (random effect model) was equal to 1.472 (95% confidence interval: 1.034-1.911). Heart rate-corrected QT dispersion values were available in 193 patients with anxiety and in 282 controls, and the summarized standardized difference in the means was equal to 3.299 (95% confidence interval: 1.215-5.384).


CONCLUSIONS
High anxiety is associated with increased QT dispersion, which may predispose to cardiac arrhythmias.
Institute of Special Education and Special Psychology of the Raoul Wallenberg International University for Family and Child, St Petersburg, Russia iakelmanson@hotmail.com.
Igor A
IA
Kelmanson
D000200:Action Potentials; D000328:Adult; D001007:Anxiety / Q000150:complications* / Q000175:diagnosis; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D012032:Refractory Period, Electrophysiological; D018570:Risk Assessment; D012307:Risk Factors; D055815:Young Adult
Anxiety; QT dispersion; arrhythmias; meta-analysis; repolarization