Table 2.
Observational studies on antipsychotic polypharmacy and corrected QT (QTc) interval
| Study | Year | Design | Diagnosis | Antipsychotic polypharmacy | Antipsychotic monotherapy | Group difference | ||||
|---|---|---|---|---|---|---|---|---|---|---|
|
|
|
|||||||||
| n (male; female) | Mean age, years | Mean QTc, ms at mg/day | n (male; female) | Mean age, years | Mean QTc, ms at mg/day | |||||
| Mackin and Young26 | 2005 | Cross-sectional | n/a | 12 (n/a; n/a) | 45.3a | 403 | 53 (n/a; n/a) | 45.3a | 416 | ns |
| Correll et al27 | 2009 | Cross-sectional | n/a | 38 (25; 13) | 40.9 | 403 at 525b,c | 73 (44; 29) | 44.5 | 408 at 245b,c | ns |
| Ramos-Ríos et al28 | 2010 | Cross-sectional | Sz | 137 (n/a; n/a) | 55.8a | n/a | 34 (n/a; n/a) | 55.8a | n/a | nsd |
| Di Sciascio et al29 | 2011 | Prospective | Sz and BD | 42 (30; 12) | 36.0 | 369 at 477b to 387 at 845b s |
33 (25; 8) | 39.2 | 365 at 398b to 363 at 449b ns |
n/a |
a
For whole patients
b
Mean chlorpromazine-equivalent dose
c
All patients were treated with atypical antipsychotics
d
The number of antipsychotics did not significantly predict QTc interval.
BD = bipolar disorder; n/a = not available or not applicable; ns = nonsignificant; s = significant; Sz = schizophrenia