Table 7. Olanzapine versus acive comparators on QT interval in people 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† |
|---|---|---|---|---|---|---|
| Olanzapine versus haloperidol in children and adolescents with autistic disorder | ||||||
| QT prolonged | 0 | 0 | RR Undetermined | 12 (1 RCT) (37,70) | Very low | No difference |
| Olanzapine versus haloperidol in adults with various mental disorders | ||||||
| QT prolonged | NR | NR | RR 0.37 (0.13, 1.05) | 433 (3 RCTs) (58,63-69) | Low | No difference |
| Change in QTc | NR | NR | SMD −0.13 (−0.34, 0.08) | 343 (2 RCTs) (58,63-69) | Moderate | No difference |
| QTc >500 milliseconds | 0 | 0 | RR Undetermined | 51 (1 RCT) (30) | Very low | No difference |
| Olanzapine versus haloperidol in adults with bipolar disorder | ||||||
| QT prolonged | 9 | 0 | RR 0.57 (0.02, 13.53) | 125(1 RCT) (74,75) | Very low | No difference |
| Intramuscular olanzapine versus haloperidol in agitated adults with schizophrenia | ||||||
| Change in QT, 2 hours after olanzapine 2.5 mg | NR | NR | MD −9.00 (−14.26, −3.74); SMD −0.41 (−0.65, −0.17) | 270 (4 RCTs) (57,63,66,78,79) | Very low | Favors olanzapine |
| Change in QT, 2 hours after olanzapine 5 mg | NR | NR | MD −9.40 (−15.16, −3.64); SMD −0.39 (−0.63, −0.15) | 270 (4 RCTs) (57,63,66,78,79) | Very low | Favors olanzapine |
| Change in QT, 2 hours after olanzapine 7.5 mg | NR | NR | MD −8.40 (−14.14, −2.66); SMD −0.35 (−0.59, −0.11) | 270 (4 RCTs) (57,63,66,78,79) | Very low | Favors olanzapine |
| Change in QT, 2 hours after olanzapine 10 mg | NR | NR | MD −5.80 (−11.53, −0.07); SMD −0.24 (−0.48, 0.00) | 270 (4 RCTs) (57,63,66,78,79) | Very low | Favors olanzapine |
| QTc prolongation >30 msec, 2 hours | 13 | 38 | RR 0.35 (0.10, 1.22) | 476 (4 RCTs) (57,63,66,78,79) | Very low | No difference |
| QTc prolongation >60 msec, 2 hours | 6 | 0 | RR 2.64 (0.13, 54.58) | 476 (4 RCTs) (57,63,66,78,79) | Very low | No difference |
| QTc prolongation >500 msec, 2 hours | 0 | 6 | RR 0.18 (0.01, 4.29) | 476 (4 RCTs) (57,63,66,78,79) | Very low | No difference |
| Change in QT, 2 hours | NR | NR | MD −3.70 (−8.25, 0.85); SMD −0.16 (−0.35, 0.03) | 476 (4 RCTs) (57,63,66,78,79) | Very low | No difference |
| Olanzapine versus asenapine in adults with schizophrenia | ||||||
| QTc ≥500 msec | 0 | 0 | RR undetermined; SMD | 1,225 (1 RCT) (71) | Very low | No difference |
| QTcF prolonged | 13 | 24 | RR 0.53 (0.18, 1.53) | 1,225 (1 RCT) (71) | Very low | No difference |
| Olanzapine versus lorazepam in agitated patients | ||||||
| Change in QTc | NR | NR | SMD −0.12 (−0.36, 0.12) | 276 (2 RCTs) (58,63-69) | Moderate | No difference |
| Olanzapine combined with fluoxetine versus fluoxetine in stabilized adults with treatment-resistant depression | ||||||
| Change in QTcF | NR | NR | MD −1.57 (−5.84, 2.70); SMD −0.07 (−0.27, 0.12) | 329 (1 RCT) (73) | Low | No difference |
| QTcF ≥500 msec | 0 | 0 | RR undetermined | 429 (1 RCT) (73) | Very low | No difference |
| Olanzapine versus olanzapine combined with lithium, valproate or carbamazepine | ||||||
| QTcF ≥450 msec for men or ≥470 msec for women | 0 | 0 | RR undetermined | 137 (1 RCT) (59) | Very low | No difference |
†, we concluded that there is no difference in outcomes between active and control interventions based on P>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; NNT, number needed to treat to achieve an outcome in one patient; NNT is calculated as 1/absolute risk difference; attributable events per 1,000 treated as the number of excessive or avoided events per 1,000 treated that are attributed to active treatment; attributable events per 1,000 treated are calculated as absolute rate difference multiplied by 1,000; 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.