Table 2. QTc interval and laboratory findings of the study groups.

Variable	Hyperthyroidism (n=38)	Controls (n=72)	P value
QTc interval (msec)	434.16±31.98	411.31±21.57	<0.001
TSH (µlU/mL)	0.09±0.29	1.31±0.77	<0.001
Free T4 (ng/dL)	4.55±2.75	1.19±0.16	<0.001
QTc interval			<0.001
Normal	24 (63.2)	67 (93.1)
Borderline	7 (18.4)	4 (5.6)
Prolongation	7 (18.4)	1 (1.4)

Values are presented as mean±standard deviation or number (%).

QTc, corrected QT; TSH, thyroid stimulating hormone; Free T4, free thyroxine.