TY - JOUR
T1 - Association between QTc prolongation and mortality in patients with suspected poisoning in the emergency department
T2 - A transnational propensity score matched cohort study
AU - Hansen, Camilla Schade
AU - Pottegård, Anton
AU - Ekelund, Ulf
AU - Kildegaard Jensen, Helene
AU - Lundager Forberg, Jakob
AU - Brabrand, Mikkel
AU - Lassen, Annmarie Touborg
PY - 2018/7
Y1 - 2018/7
N2 - Objectives Poisoning is a frequent cause of admission to the emergency department (ED) and may involve drugs known to prolong the QT interval. This study aims to describe the prevalence of QTc prolongation among ED patients with suspected poisoning and to calculate the absolute and relative risk of mortality or cardiac arrest associated with a prolonged QTc interval. Methods We performed a register-based cohort study, including all adult first-time contacts with suspected poisoning to the ED of two Swedish hospitals (January 2010-December 2014) and two Danish hospitals (March 2013-April 2014). We used propensity score matching to calculate HRs for all-cause mortality or cardiac arrest (combined endpoint) within 30 days after contact comparing patients with a prolonged QTc interval (≥450 ms men, ≥460 ms women) with patients with a QTc interval of <440 ms. Results Among all first-time contacts with suspected poisoning that had an ECG recorded within 4 hours after arrival (n=3869), QTc prolongation occurred in 6.5%. The overall mortality after a 30-day follow-up period was 0.8% (95% CI 0.6 to 1.2), with an absolute risk of mortality or cardiac arrest in patients with QTc prolongation of 3.2% (95% CI 1.4 to 6.1). A prolonged QTc interval on arrival was associated with a HR of 3.6 (95% CI 1.0 to 12.2). Conclusion In the ED, a prolonged QTc interval in patients arriving with suspected poisoning seems to be associated with a threefold increased risk of 30-day all-cause mortality or cardiac arrest.
AB - Objectives Poisoning is a frequent cause of admission to the emergency department (ED) and may involve drugs known to prolong the QT interval. This study aims to describe the prevalence of QTc prolongation among ED patients with suspected poisoning and to calculate the absolute and relative risk of mortality or cardiac arrest associated with a prolonged QTc interval. Methods We performed a register-based cohort study, including all adult first-time contacts with suspected poisoning to the ED of two Swedish hospitals (January 2010-December 2014) and two Danish hospitals (March 2013-April 2014). We used propensity score matching to calculate HRs for all-cause mortality or cardiac arrest (combined endpoint) within 30 days after contact comparing patients with a prolonged QTc interval (≥450 ms men, ≥460 ms women) with patients with a QTc interval of <440 ms. Results Among all first-time contacts with suspected poisoning that had an ECG recorded within 4 hours after arrival (n=3869), QTc prolongation occurred in 6.5%. The overall mortality after a 30-day follow-up period was 0.8% (95% CI 0.6 to 1.2), with an absolute risk of mortality or cardiac arrest in patients with QTc prolongation of 3.2% (95% CI 1.4 to 6.1). A prolonged QTc interval on arrival was associated with a HR of 3.6 (95% CI 1.0 to 12.2). Conclusion In the ED, a prolonged QTc interval in patients arriving with suspected poisoning seems to be associated with a threefold increased risk of 30-day all-cause mortality or cardiac arrest.
KW - cardiology
KW - epidemiology
KW - toxicology
U2 - 10.1136/bmjopen-2017-020036
DO - 10.1136/bmjopen-2017-020036
M3 - Article
C2 - 29982199
AN - SCOPUS:85049984154
SN - 2044-6055
VL - 8
JO - BMJ Open
JF - BMJ Open
IS - 7
M1 - e020036
ER -