Objective To examine whether a history of stressful life events and prolonged mental stress are associated with arrhythmic events in inherited long QT syndrome (LQTS).

Methods Participants who had a molecularly established mutation of KCNQ1, KCNH2 or SCN5A channel and were thus diagnosed as patients with LQT1, LQT2 and LQT3 (n=566), accordingly. The control group consisted of their 614 non-affected relatives. A history of stressful life events was indexed by the major stressful life events. Prolonged mental stress was indexed by vital exhaustion (VE), which was measured with the Maastricht Questionnaire.

Results Multinomial logistic regression analysis including patients with LQTS with and without arrhythmic events and the control subjects showed an age- and sex-adjusted association of stressful life events OR=1.15 (95% CI 1.08 to 1.22) and VE (OR=3.33 (95% CI 1.63 to 6.78)) with symptomatic status of LQTS. Symptomatic patients with LQTS had experienced more stressful life events (OR=1.16 (95% CI 1.08 to 1.24)) and the level of VE (OR=3.40 (95% CI 1.44 to 8.03)) was more than three times higher among patients with LQTS with arrhythmic events than in asymptomatic LQTS mutation carriers. The association between stressful life events and arrhythmic events was independent of age, sex, specifically focused medication and LQTS subtype.

Conclusions A history of stressful life events and prolonged mental stress are associated with arrhythmic events in LQTS in this large sample of molecularly defined patients with LQTS. It is important for future studies to assess how strong these predisposing factors are for arrhythmic events in LQTS.