Table 6. Olanzapine versus placebo 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 placebo in children and adolescents | ||||||
| Change in QTc | NR | NR | MD −1.01 (−6.45, 4.43); SMD −0.04 (−0.18, 0.11) | 1,174 (5 studies) (35,60-62) | Very low | No difference |
| Oral olanzapine versus placebo in adults | ||||||
| QT prolonged | NR | NR | RR 0.34 (0.16, 0.70) | 869 (6 RCTs) (58,63-69) | Low | No difference* |
| QT prolonged | 9 | 20 | RR 0.46 (0.04, 4.96) | 201(1 RCT) (74,75) | Very low | No difference |
| Change in QTc | NR | NR | SMD −0.14 (−0.29, 0.01) | 724 (7 RCTs) (58,63-69) | Moderate | No difference |
| Intramuscular olanzapine versus placebo in adults | ||||||
| QTc prolongation >30 msec, 2 hours | 15 | 21 | RR 0.73 (0.18, 2.86) | 556 (4 RCTs) (57,63,66,78,79) | Very low | No difference |
| QTc prolongation >60 msec, 2 hours | 5 | 7 | RR 0.73 (0.07, 7.94) | 556 (4 RCTs) (57,63,66,78,79) | Very low | No difference |
| QTc prolongation >500 msec, 2 hours | 0 | 0 | RR Undetermined | 556 (4 RCTs) (57,63,66,78,79) | Very low | No difference |
| Change in QT, 2 hours after olanzapine 2.5 mg in agitated adults with schizophrenia | NR | NR | MD −5.90 (−10.61, −1.19); SMD −0.30 (−0.54, −0.06) | 270 (4 RCTs) (57,63,66,78,79) | Very low | Favors olanzapine |
| Change in QT, 2 hours after olanzapine 5 mg in agitated adults with schizophrenia | NR | NR | MD −6.30 (−11.56, −1.04); SMD −0.29 (−0.53, −0.05) | 270 (4 RCTs) (57,63,66,78,79) | Very low | Favors olanzapine |
| Change in QT, 2 hours after olanzapine 7.5 mg in agitated adults with schizophrenia | NR | NR | MD −5.30 (−10.54, −0.06); SMD −0.24 (−0.48, 0.00) | 270 (4 RCTs) (57,63,66,78,79) | Very low | Favors olanzapine |
| Change in QT, 2 hours after olanzapine 10 mg in agitated adults with schizophrenia | NR | NR | MD −2.70 (−7.92, 2.52); SMD −0.12 (−0.36, 0.12) | 270 (4 RCTs) (57,63,66,78,79) | Very low | No difference |
| Change in QT, 2 hours after olanzapine 2.5 mg in adults with dementia | NR | NR | MD −7.80 (−12.92, −2.68); SMD −0.36 (−0.60, −0.12) | 272 (4 RCTs) (57,63,66,78,79) | Very low | Favors olanzapine |
| Change in QT, 2 hours after olanzapine 5 mg in adults with dementia | NR | NR | MD −0.20 (−5.65, 5.25); SMD −0.01 (−0.25, 0.23) | 272 (4 RCTs) (57,63,66,78,79) | 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. *, no statistically significant differences in absolute risk. 95% confidence interval in (); GRADE, Grading of Recommendations Assessment, Development and Evaluation; 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; NR, not reported.