Cloninger's temperament traits and inherited long QT syndrome

The long QT syndrome (LQTS) is an inherited cardiac disorder which predisposes the mutation carrier to ventricular arrhythmias that can lead to sudden death. The objective of the present study was to examine the association between the symptom status of congenital long QT syndrome mutation carriers and their temperament.

The study subjects included 587 LQTS mutation carriers from the Finnish LQTS registry, and 2056 individuals from a database study, the Young Finns Study (YFS), representing general population and serving as control subjects. The LQTS subjects were divided into symptomatic (n=259) and asymptomatic (n=328) groups, according to their history of arrhythmic events. Temperament was assessed using the Cloninger's Temperament and Character Inventory (TCI), assessing novelty seeking, harm avoidance and reward dependence.

Congenital long QT syndrome mutation carriers had a higher harm avoidance (HA) than those representing the general population (2.77 vs. 2.61, p<.001, η²=0.011). Symptomatic and asymptomatic LQTS mutation carriers did not differ from one another in any of the three Cloninger's temperament traits. HA was significantly higher in women (2.72 vs. 2.54, p<0.001 η²=0.017).

LQTS mutation carriers may have higher stress proneness because of their high HA, which in turn may predispose them to the effects of environmental loading and thus increase the risk of arrhythmias.