Table 9. Quetiapine versus other antipsychotics on QT interval in adults with mental disorders.
| Outcome | Risk with intervention per 1,000 | Risk with comparator per 1,000 | Relative measure of association | Number of participants (studies) | Quality (GRADE) | Comments† |
|---|---|---|---|---|---|---|
| Quetiapine versus haloperidol | ||||||
| QTc >500 milliseconds | 0 | 0 | RR undetermined | 54 (1 RCT) (30,38) | Very low | No difference |
| Quetiapine versus olanzapine | ||||||
| Torsade’s de Pointes, sudden cardiac death | NR | NR | Adjusted HR 0.73 (0.57, 0.93) | 459,614 (1 observational study of Medicaid programs) (33) | Very low | Favors quetiapine |
| Quetiapine versus risperidone | ||||||
| Electrocardiogram QT Prolonged | 1 | 0 | RR 2.54 (0.10, 62.20) | 1,082 (1 RCT) (83) | Very low | No difference |
| Quetiapine versus ziprasidone | ||||||
| QTc >60 msec | 0 | 0 | RR undetermined | 70 (1 RCT) (82) | Very low | No difference |
| Change in QTcF | NR | NR | MD −8.30 (−13.48, −3.12); SMD −0.75 (−1.24, −0.27) | 70 (1 RCT) (82) | Very low | Favors quetiapine |
| Change in QTc | NR | NR | MD −8.20 (−13.38, −3.02); SMD −0.74 (−1.23, −0.26) | 70 (1 RCT) (82) | Very low | Favors quetiapine |
| Change in QTc (FDA) | NR | NR | MD −7.00 (−12.25, −1.75); SMD −0.62 (−1.11, −0.14) | 70 (1 RCT) (82) | Very low | Favors quetiapine |
| Change in QTc (Bazett) | NR | NR | MD −2.10 (−8.43, 4.23); SMD −0.16 (−0.62, 0.31) | 70 (1 RCT) (82) | Very low | No difference |
†, we concluded that there is no difference in outcomes between active and control interventions based on P value >0.05 and inability to reject null hypotheses but without post-hoc analysis of the statistical power to detect true differences. 95% confidence interval in (); GRADE, Grading of Recommendations Assessment, Development and Evaluation; HR, hazard ratio; RCT, randomized controlled trial; RR, relative risk; MD, mean difference; SMD, standardized mean difference between intervention and comparator where the magnitude of the effect is defined as small (SMD, 0–0.5 standard deviations), moderate (SMD, 0.5–0.8 standard deviations), and large (SMD >0.8 standard deviations); QTc, corrected QT interval; QTcF, Fridericia’s corrected QT interval; NR, not reported.