Change and dispersion of QT interval during treatment with quetiapine extended release versus aripiprazole in children and adolescents with first-episode psychosis: results from the TEA trial

The aim of this study was to compare the effect of quetiapine extended release (ER) versus aripiprazole on corrected QT interval (QTc) and QT dispersion (QTd) in youths with first-episode psychosis. Youths 12-17 years were randomized to quetiapine ER (daily dose range = 50 to 800 mg) or aripiprazole (daily dose range = 2.5 to 30 mg) in a 12-week double-blinded trial and examined at weeks 0, 4, and 12. Primary outcome was QTc change using Hodges formula (QTcH); secondary outcomes included QTcH > 450 ms, QTcH > 500 ms, QTcH change > 60 ms, QTd, and heart rate (HR). Among 113 randomized youths, follow-up ECG was available for 93 patients (82.3%) (age = 15.8 +/- 1.3 years, males = 34.4%, schizophrenia = 67.7%). Quetiapine ER treatment (n = 47) was associated with a significant increase in QTcH of + 6.8 +/- 20.2 ms (p = 0.025), while the change from baseline in patients receiving aripiprazole (n = 46) was non-significant (- 3.4 +/- 18.9 ms, p = 0.225). One patient in the quetiapine ER group had a QTcH change of + 62.3 ms. Age, sex, smoking, body mass index, and concomitant medication were not significantly associated with QTcH change, but higher baseline potassium was correlated to higher QTcH change in the quetiapine ER group. The HR increased significantly with quetiapine ER (+ 11.0 +/- 14.2 bpm, p < 0.001) but not with aripiprazole (- 0.8 +/- 12.0 bpm, p = 0.643). QTd did not significantly change with quetiapine ER or aripiprazole. QTcH and HR increased significantly with quetiapine ER, although changes were small and likely not clinically significant in otherwise healthy patients. QTcH and HR were unchanged with aripiprazole. No significant change in QTd was seen. ClinicalTrials.gov: NCT01119014, EudraCT: 2009-016715-38.