Large placebo response presents a major challenge for psychopharmacologic drug development and contributes to the increasing failure of psychiatric trials. The objective of this meta-regression ...analysis was to identify potential contributors to placebo response in randomized controlled trials of antipsychotic treatment in schizophrenia.
The authors extracted trial design and clinical variables from eligible randomized controlled trials (N=50) identified through searches of MEDLINE (1960-2010) and other sources. Standardized mean change (SMC) was used as the effect size measure for placebo response, based on change scores on the Brief Psychiatric Rating Scale or the Positive and Negative Syndrome Scale from baseline to endpoint (2 to 12 weeks).
The results suggest significant heterogeneities (Q=387.83, df=49) in the magnitude of placebo response (mean SMC, -0.33, range -1.4 to 0.9) and in study quality. Both placebo SMC and study quality increased over time. Younger age, shorter duration of illness, greater baseline symptom severity, and shorter trial duration were significantly associated with greater placebo response, while country (United States compared with other countries) was not. More study sites, fewer university or Veterans Affairs treatment settings, and a lower percentage of patients assigned to receive placebo were associated with a greater placebo response, but these were not independent of publication year. Study quality affected the variability but not mean levels of placebo response.
This study identified important patient characteristics and trial design factors affecting the level of placebo response and hence the likelihood of detecting efficacy signals in randomized controlled trials. Future studies should test whether controlling these factors improves the detection of an antipsychotic effect.
Research and clinical translation in schizophrenia is limited by inconsistent definitions of treatment resistance and response. To address this issue, the authors evaluated current approaches and ...then developed consensus criteria and guidelines.
A systematic review of randomized antipsychotic clinical trials in treatment-resistant schizophrenia was performed, and definitions of treatment resistance were extracted. Subsequently, consensus operationalized criteria were developed through 1) a multiphase, mixed methods approach, 2) identification of key criteria via an online survey, and 3) meetings to achieve consensus.
Of 2,808 studies identified, 42 met inclusion criteria. Of these, 21 studies (50%) did not provide operationalized criteria. In the remaining studies, criteria varied considerably, particularly regarding symptom severity, prior treatment duration, and antipsychotic dosage thresholds; only two studies (5%) utilized the same criteria. The consensus group identified minimum and optimal criteria, employing the following principles: 1) current symptoms of a minimum duration and severity determined by a standardized rating scale; 2) moderate or worse functional impairment; 3) prior treatment consisting of at least two different antipsychotic trials, each for a minimum duration and dosage; 4) systematic monitoring of adherence and meeting of minimum adherence criteria; 5) ideally at least one prospective treatment trial; and 6) criteria that clearly separate responsive from treatment-resistant patients.
There is considerable variation in current approaches to defining treatment resistance in schizophrenia. The authors present consensus guidelines that operationalize criteria for determining and reporting treatment resistance, adequate treatment, and treatment response, providing a benchmark for research and clinical translation.
Abstract This double-blind study evaluated change in cognitive performance and functional capacity in lurasidone and quetiapine XR-treated schizophrenia patients over a 6-week, placebo-controlled ...study, followed by a 6-month, double-blind extension. Cognitive performance and functional capacity were assessed with the CogState computerized cognitive battery and the UPSA-B. Analyses were conducted for all subjects, as well as the subsample whose test scores met prespecified validity criteria. No statistically significant differences were found for change in the composite neurocognitive score for lurasidone (80 mg/day and 160 mg/day) groups, quetiapine XR and placebo in the full sample at week 6. For the evaluable sample ( N =267), lurasidone 160 mg was superior to both placebo and quetiapine on the neurocognitive composite, while lurasidone 80 mg, quetiapine XR, and placebo did not differ. UPSA-B scores were superior to placebo at 6 weeks for all treatments. In the double-blind extension study, analysis of the full sample showed significantly better cognitive performance in the lurasidone (40–160 mg) group compared to the quetiapine XR (200–800 mg) group at both 3 and 6 months. Cognitive and UPSA-B total scores were significantly correlated at baseline and for change over time. This is the first study to date where the investigational treatment was superior to placebo on both cognitive assessments and a functional coprimary measure at 6 weeks, as well as demonstrated superiority to an active comparator on cognitive assessments at 6 weeks and at 6 months of extension study treatment. These findings require replication, but are not due to practice effects, because of the placebo and active controls.
Abstract We previously reported that treatment with 160 mg/d of lurasidone improved cognitive performance in a manner superior to placebo, quetiapine XR 600 mg/d, and lurasidone 80 mg/d, based on a ...6-week randomized trial of patients with an acute exacerbation of schizophrenia. The objective of this post-hoc analysis was to explore the cognitive and functional performance of patients whose final doses of lurasidone were 40/80 mg/d, 120 mg/d, and 160 mg/d compared to quetiapine XR 200-800 mg/d (QXR) during a 6-month, double-blind continuation study that followed a short-term trial. Subjects who received final doses of lurasidone 120 mg/d (n = 77) and 160 mg/d (n = 49) showed significantly greater improvement in overall cognitive performance compared to QXR (n = 85) at week 32 (month 6 of the extension study), while those on last doses of 40/80 mg/d (n = 25) showed a trend towards significance at week 32. Mean changes in neurocognitive composite z-score from pre-treatment baseline were significant for the 3 lurasidone final dose groups at both weeks 19 and 32, with composite change scores of z = 1.53, z = 1.43, and z = 1.34 for the lurasidone 40/80 mg/d, 120 mg/d, and 160 mg/d, respectively, at week 32. In contrast, the composite change score was not statistically significant in the overall quetiapine group (z = 0.46), with none of the individual quetiapine doses showing any significant improvement. Functional capacity scores improved in all treatment groups. Our findings indicate improved cognitive performance in patients treated with each of the flexible doses of lurasidone 40–160 mg/d, compared to quetiapine XR 200–800 mg/d. All doses of lurasidone were superior to all doses of quetiapine for cognitive performance.
Associations of the serotonin transporter promoter polymorphism (5-HTTLPR) with bipolar disorder (BPD) and treatment response in bipolar patients were not conclusive. This study not only assessed the ...association between the 5-HTTLPR and BPD with accumulating relevant studies, but also in the first time evaluated the effect of the 5-HTTLPR on both anti-depressive and anti-manic treatment responses in bipolar patients.
PubMed, Embase, PsycINFO, Cochrane Library and Cochrane Control Trials databases were systematically searched before February 2017. This meta-analysis followed the PRISMA guidelines.
A total of 32 population-based studies (5567 cases and 6993 controls) and 9 family-based studies (837 trios) were finally screened out and statistically joined into a single meta-analysis that revealed an association between S allele and an increased risk of BPD (OR = 1.06, p = .038). Pooled analysis of the 32 population-based studies indicated an association of S-carrier genotypes with an increased risk of BPD (OR = 1.10, p = .029). Meanwhile, the association remained significant in Caucasians (OR = 1.15, p = .004), which could provide an enough power (88%) to detect a significant association. Regarding the treatment response studies, 6 studies reporting the relationship of the 5-HTTLPR in anti-depressive remission rate (1034 patients) and 7 studies reporting in response rate (1098 patients) were included for pooled analyses. We observed a significant association of S-carrier genotypes with a reduced anti-depressive remission rate (OR = 0.64, p = .006) but not with anti-depressive response rate. The association between the 5-HTTLPR with anti-manic response rate was not observed in the included 6 studies (676 patients).
The present study supported the presence of a marginal but detectable effect of the 5-HTTLPR on susceptibility to BPD. Moreover, the detected association in Caucasian was statistically reliable. Besides, the 5-HTTLPR was identified as a useful predictor for anti-depressive remission but not for anti-depressive or anti-manic response.
•This study not only assessed association of the 5-HTTLPR with BPD, but also evaluated effect of the 5-HTTLPR on treatment response.•A marginal but detectable effect of the 5-HTTLPR on BPD was observed in combined analysis of population-based and family-based studies.•The marginal effect was also demonstrated in separate analysis including 32 population-based studies only.•The included sample size in Caucasian from population-based studies can provide an enough power to detect a significant association.•The 5-HTTLPR was identified as a useful predictor for anti-depressive remission (p = .006) but not for anti-depressive or anti-manic response.
Accumulating evidence has implicated insulin resistance and inflammation in the pathophysiology of cognitive impairments associated with neuropsychiatric disorders. This post-hoc analysis based on a ...placebo-controlled trial investigated the effect of inflammation (indexed by CRP) and metabolic risk factors on cognitive performance in patients with schizophrenia treated with lurasidone.
Acutely exacerbated patients with schizophrenia were randomized to lurasidone (80 or 160 mg/day), quetiapine XR 600 mg/day, or placebo. A wide range CRP test and a cognitive assessment using the CogState computerized battery were performed at baseline and week 6 study endpoint. Associations between log-transformed CRP, high density lipoprotein (HDL), homeostatic model assessment of insulin resistance (HOMA-IR) and treatment response were evaluated.
CRP combined with HDL, triglyceride-to-HDL (TG/HDL) ratio, or HOMA-IR at study baseline were significant moderators of the improvement in cognitive performance associated with lurasidone 160 mg/day (vs. placebo) treatment (p < .05). Greater placebo-corrected treatment effect size on the CogState composite score was observed for patients in the lurasidone 160 mg/day treatment group who had either low CRP and high HDL (d = 0.43), or low CRP and low HOMA-IR (d = 0.46). Interactive relationships between CRP, HDL, TG/HDL, HOMA-IR and the antipsychotic efficacy of lurasidone or quetiapine XR were not significant. There were no significant associations between antipsychotic treatment and changes in CRP level at study endpoint.
Findings of this post-hoc analysis based on a placebo-controlled trial in patients with schizophrenia suggest that baseline CRP level combined with measures of metabolic risk significantly moderated the improvement in cognitive performance associated with lurasidone 160 mg/day (vs. placebo) treatment. Our findings underscore the importance of maintaining a low metabolic risk profile in patients with schizophrenia.
•Baseline CRP level, combined with measures of metabolic risk, moderated cognitive response to lurasidone in schizophrenia•Improved cognitive performance was associated with low CRP combined with a healthier lipid or insulin resistance profile•Our cognitive performance findings underscore the need to maintain a low metabolic risk profile in patients with schizophrenia
Suicide is a fatal outcome for subjects with mental ill-health. Genetic factors and psychological correlates are believed to contribute to the risk of suicide attempts (SA), whereas both factors are ...reported to exert a small effect. This study therefore tried to investigate if combination of the two aspects can enhance the explanation of variance in SA.
A common variant rs7713917 in HOMER1 gene was genotyped for 333 Chinese psychiatric patients with or without SA. Multifactorial risk models comprised of this variant and psychological correlates were identified by logistic regression analysis (LRA) and Multifactor Dimensionality Reduction (MDR) method separately, and then evaluated for their performance by biostatistical methods.
An association of A-carrier genotypes in rs7713917 with an increased risk of SA was observed (OR = 1.79, 95% CI = 1.08–2.98). Although with a medium effect size, this variant alone could only explain 1.9% variance of SA. Interestingly, this study was the first time to show that the association of the rs7713917 and SA was significantly mediated by the NEO conscientiousness (NEOC) dimension (p-value = 0.002), with a greater genetic effect observed in subjects with a low NEO-C level (OR = 2.89, 95% CI = 1.16–7.18) but not in subjects with an average or high level. Upon the LRA method, the multifactorial risk model constituted of the two interacted factors and their interaction effect could explain up to 17.0% variance, which was almost 9-fold higher than the one explained by the rs7713917 alone. Furthermore, this model owned a higher effectiveness than the three models identified by the MDR method (p-value < 0.0007).
The present study identified an effective multifactorial risk model, in which the combination of the HOMER1 variant and the NEO-C dimension could enhance explanation of the variance of SA in Chinese. This pilot study may provide a novel avenue to investigate the pathogenesis of SA in psychiatric patients.
•The associated variant HOMER1 rs7713917 alone could only explain 1.9% variance of SA.•The association between the rs7713917 and SA was significantly mediated by the NEO-C dimension.•The identified effective multifactorial risk model could explain up to 17.0% variance of SA.•The variance of SA explained by the multifactorial risk model was almost 9-fold higher.•Combination of genetic variants and psychological correlates enhanced the explained variance of SA.
Available data on antipsychotic-induced metabolic risks are often constrained by potential confounding effects due to prior antipsychotic treatment. In this study, we assessed the baseline prevalence ...of metabolic abnormalities and changes following treatment with five commonly-used antipsychotic drugs (haloperidol, amisulpride, olanzapine, quetiapine or ziprasidone) in first-episode, partially antipsychotic-naive patients with schizophrenia in the European first-episode schizophrenia trial (EUFEST). Overall baseline prevalence of metabolic syndrome (MetS) was 6.0%, with similar rates observed in the antipsychotic-naive patients (5.7%, 9/157) and in the other patients with only a brief prior exposure to antipsychotics (6.1%, 20/326). These results are consistent with the MetS prevalence rate estimated in a general population of similar age. Examination of individual risk factors showed 58.5% of subjects had one or more elevated metabolic risks at baseline: 28.5% demonstrated suboptimal HDL; 24.2% hypertension; 17.7% hypertriglyceridemia; 8.2% abdominal obesity; 7.3% hyperglycaemia. Increase in body weight (kg/month) occurred in patients treated with haloperidol (0.62 s.e. 0.11), amisulpride (0.76 s.e. 0.08), olanzapine (0.98 s.e. 0.07) and quetiapine (0.58 s.e. 0.09), which was significantly greater than that in the ziprasidone group (0.18 s.e. 0.10). The incidence rate of new diabetes cases over a 52-wk follow-up period was 0.82% (4/488). More patients experienced worsening rather than improvement of hypertriglyceridemia or hyperglycaemia in all treatment groups. Our findings suggest that in first-episode, partially antipsychotic-naive patients, the baseline prevalence rate of MetS appears to be no higher than that in the general population, but serious underlying individual risk factors nevertheless existed.
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