TABLE 2.
Summary and characteristics of included studies with AP comparisons.
| Study | Dx | Country of study | Setting | % Male | Mean age ± SD | N | Study type | Antipsychotic use timeframe | Definition of nonadherence/discontinuation in study | Weight gain‐related nonadherence/discontinuation used in meta‐analysis | Other metabolic variables considered in relation to treatment discontinuations |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Ader 2008 | SCZ or schizoaffective or schizophreniform disorder | US | All patients |
OLZ: 58.1 RIS: 7 8.6 |
OLZ: 39.6 ± 8.3 RIS: 39.8 ± 7.6 |
59 | Double‐blind RCT | 24‐week treatment on RIS or OLZ | Treatment discontinuation due to weight gain. |
OLZ: 1/31 RIS: 0/28 |
N |
| Bobes 2003 | SCZ | Spain | Outpatients |
OLZ: 61.4 HAL: 60.5 RIS: 64.2 QUE:51.2 |
HAL: 41.2 ± 12.3 OLZ: 35.7 ± 12.8 RIS: 36.1 ± 11.5 QUE: 32.2 ± 10.5 |
636 evaluated | Cross‐sectional, retrospective, naturalistic | At least 4 weeks | Treatment discontinuation due to weight gain. |
OLZ: 8/133 HAL: 0/39 RIS: 1/96 QUE: 0/4 For OLZ versus other APs comparison: HAL, RIS, and QUE combined: 1/139 For RIS, QUE and PP versus other APs comparison: RIS and QUE combined: 1/100 and compared with HAL Reported n here = number of patients with weight gain data recorded in the UKU with information about requirement of any related action |
N |
| Citrome 2015 | SCZ | US | Multicentre (outpatients) | Total: 67 | 43.3 ± 11.0 | 500 | Open label randomized switch study | Previous AP use timeframe not reported. However, there were 12 weeks of iloperidone monotherapy | Discontinuation of APs due to weight gain who were then switched to iloperidone to combat weight gain (i.e., switch study). |
OLZ: 39/155 ARI: 16/170 RIS: 22/175 ARI and RIS combined: 38/345 |
N |
| Hofer 2017 | SCZ spectrum disorders | Austria | Inpatients and outpatients | Total: 59.3 | 35.5 ± 9.2 | 194 | Post‐hoc analysis of a naturalistic study | Follow up was for a maximum of 12 months | Treatment discontinuation due to weight gain. |
OLZ: 1/49 RIS: 2/33 AMI: 0/39 ARI: 0/13 QUE: 0/22 SER: 0/8 ZIP: 0/24 ZOT: 0/6 All APs other than OLZ combined for comparison = 2/145 |
Y |
| Huang 2018 | First episode, drug‐naive SCZ patients | China | Inpatients and outpatients |
PP: 60.7 OLZ: 70 |
PP: 21.54 ± 5.60 OLZ: 23.79 ± 5.89 |
57 | RCT | 13‐week study assessing efficacy of PP and OLZ in patients | Discontinuation |
OLZ: 0/29 PP: 1/28 |
N |
| Kinon 2006 | SCZ, schizophreniform disorder, or schizoaffective disorder | US | Inpatients and outpatients | Total: 64.4 | 39.53 ± 10.85 | Total: 1627 | Post‐hoc pooled analysis of four double‐blind RCTs | 24–28‐week exposure to OLZ versus other APs | Discontinuation |
OLZ: 3/822 RIS: 0/167 QUE: 0/175 ZIP: 0/463 All APs other than OLZ combined for comparison: 0/805 |
N |
| Kishi 2021 | SCZ and related psychotic disorders | Japan | Inpatients | NR | NR | 157 | Retrospective chart review | Ranged from 2 to 48 months | Treatment discontinuation due to weight gain. |
PP: 2/41 RIS LAI: 0/58 ARI: 0/58 PP and RIS combined: 2/99 |
N |
| Matsuzaki 2021 | SCZ or schizoaffective disorder | Japan | Hospital |
ASE: 39.1 OLZ: 36.7 |
ASE: 42.0 ± 15.3 OLZ: 43.8 ± 15.6 |
95 | Retrospective chart review | Initiated on either ASE or OLZ, with discontinuation assessed at 1 and 6 months | Treatment discontinuation due to weight gain. |
OLZ: 7/49 ASE: 1/46 |
N |
| McEvoy 2014 | SCZ, schizoaffective disorder | US | Multicentre (inpatients and Outpatients) |
PP: 73.1 HAL: 75.9 |
PP: 43 ± 12.6 HAL: 45 ± 12.3 |
311 randomized, 290 included in primary analysis | Double‐blind RCT | Up to 24 months | Treatment discontinuation due to weight gain. |
PP: 7/145 HAL: 2/145 |
N |
| Montes 2007 | SCZ or schizoaffective disorder | Spain | Multicentre (outpatients) | Total: 50.7 | 35.0 ± 11.7 | 67 | Open‐label, flexible‐dose, prospective | Previous AP use timeframe: 31.4 months. ZIP treatment was reported to be for 6 months. | Switching due to weight gain |
OLZ: 37/40 RIS: 17/20 HAL: 0/3 FLZ: 0/1 QUE: 0/1 AMI: 0/1 QUE + RIS: 0/1 All APs other than OLZ combined for comparison = 17/27 |
Y |
| Piparva 2011 | Psychotic disorder | India | Outpatients | Total: 70.27 | Unknown (any age included) | 84 | Observational, prospective | Up to 18 months of follow up exploring adverse drug reactions on various atypical APs | Treatment discontinuation due to weight gain. |
OLZ: 4/34 CLZ: 0/6 RIS: 0/38 QUE: 0/5 ARI: 0/1 All APs other than OLZ and CLZ combined for comparison: 0/44 |
N |
| Shajahan 2009 | SCZ, persistent delusional disorders, schizoaffective disorder and depressive disorder with psychotic symptoms | UK | Outpatients |
ARI: 58 QUE: 52 |
ARI: 39.6 (37.3 to 41.9) QUE: 36.7 (34.1 to 39.3) |
221 | Retrospective chart review (electronic) |
ARI: 488 days (403 to 572) QUE: 450 days (361 to 540) |
Treatment discontinuation due to weight gain. |
ARI: 0/89 QUE: 3/132 |
N |
| Wang 2022 | SCZ | Multicentre | Inpatients and outpatients | Total: 77.9 |
PP: 33.42 ± 11.77 OLZ: 33.10 ± 8.48 |
PP: 45 OLZ: 41 |
Double‐blind RCT | 12 weeks on PP extended release or OLZ | Treatment discontinuation due to weight gain |
OLZ: 1/41 PP: 0/45 |
N |
| Zhou 2023 | SCZ | China | Inpatients and outpatients | Total: 50.69 | 25.13 ± 7.10 | 493 | Open‐label RCT | Assigned to a different AP after <4 weeks of continuous treatment with the previous AP (cumulative lifetime AP exposure <12 weeks) | Switched APs due to weight gain within the first 4 weeks after randomization. |
OLZ: 16/163 ARI: 1/161 RIS: 11/169 All APs other than OLZ combined for comparison: 12/330 |
N |
Abbreviations: AMI, amisulpride; ARI, aripiprazole; ASE, asenapine; CLZ, clozapine; Dx, diagnosis; FLZ, fluphenazine; HAL, haloperidol; NR, not reported; OLZ, olanzapine; PP, paliperidone palmitate; QUE, quetiapine; RIS, risperidone; SCZ, schizophrenia; SER, sertindole; ZIP, ziprasidone; ZOT, zotepine.