Gender differences in the response to antipsychotic medication in patients with schizophrenia: An individual patient data meta-analysis of placebo-controlled studies

OBJECTIVE

To determine whether gender and menopausal status moderate the response to antipsychotic medication in patients with schizophrenia.

METHODS

We analyzed data of 22 short-term placebo-controlled registration trials of antipsychotic medications, which included 5,231 patients with schizophrenia. We applied two-step individual patient data meta-regression analyses to establish the influence of gender and menopausal status on treatment response in mean difference in symptom severity and difference in response (>30% symptom reduction). Analyses were performed both with and without correction for baseline (negative) symptom severity.

RESULTS

Antipsychotic treatment is associated with larger mean symptom reduction in women than in men with schizophrenia. The number needed to treat (NNT) for a response in women was 6.9, in men 9.4. Although, we found an age by gender effect, the gender by treatment effect was independent of premenopausal status and baseline (negative) symptom severity.

CONCLUSION

In the treatment of schizophrenia we found evidence of a higher response to antipsychotic medication in women relative to men. We found no evidence that this effect was driven by menopausal status, or baseline (negative) symptom severity. Despite the impact of gender and age on effect size in acute antipsychotic treatment, efficacy was clinically relevant in all subgroups.

Sex Proportionality in Pre-clinical and Clinical Trials: An Evaluation of 22 Marketing Authorization Application Dossiers Submitted to the European Medicines Agency

This study assessed to what extent women were included in all phases of drug development; whether the clinical studies in the marketing authorization application dossiers include information per sex; and explored whether there are differences between women and men in the drugs' efficacy and safety. Data were extracted from dossiers submitted to the European Medicines Agency. Twenty-two dossiers of drugs approved between 2011 and 2015 for the treatment of various diseases were included. Female animals were included in only 9% of the pharmacodynamics studies, but female and male animals were included in all toxicology studies. Although fewer women than men were included in the clinical studies used to evaluate pharmacokinetics (PK) (29 to 40% women), all dossiers contained sex-specific PK parameter estimations. In the phase III trials, inclusion of women was proportional to disease prevalence for depression, epilepsy, thrombosis, and diabetes [participation to prevalence ratio (PPR) range: 0.91–1.04], but women were considered underrepresented for schizophrenia, hepatitis C, hypercholesterolemia, HIV, and heart failure (PPR range: 0.49-0.74). All dossiers contained sex-specific subgroup analyses of efficacy and safety. There seemed to be higher efficacy for women in one dossier and a trend toward lower efficacy in another dossier. More women had adverse events in both treatment (73.0 vs. 70.6%, p < 0.001) and placebo groups (69.5 vs. 65.5%, p < 0.001). In conclusion, women were included throughout all phases of clinical drug research, and sex-specific information was available in the evaluated dossiers. The included number of women was, however, not always proportional to disease prevalence rates.

Assessment of the Regulatory Dialogue Between Pharmaceutical Companies and the European Medicines Agency on the Choice of Noninferiority Margins

Choosing a noninferiority margin is one of the main challenges when designing a noninferiority trial. The European Medicines Agency (EMA) published a guidance report on the choice of margins in 2005. Nonetheless, in 2008 and 2009 they did not accept 41% (35 of 86) of the noninferiority margins that were proposed by pharmaceutical companies in the context of scientific-advice letters. In this study, we focus on whether the EMA's recommendations were followed by pharmaceutical companies, and on a possible relationship with eventual drug approval. Five of the 35 unaccepted margins were equivalence margins; we considered only the 30 unaccepted noninferiority margins in our analysis. Twelve of these margins were defined based on clinical and statistical considerations (the approach recommended by the EMA) and were rejected due to unacceptable clinical considerations. The other 18 margins were rejected because they were considered too wide. The EMA's recommendations were followed in the cases of 10 of the 15 margins (67%) for which information on follow-through of recommendations was available. The main reason for ignoring the EMA's recommendation in the other 5 cases was that the margins had been accepted by the US Food and Drug Administration. The proportions of approved drugs for which recommendations were and were not followed were similar, yet numbers were too low for formal statistical testing. This study shows that the main concern of regulators with regard to noninferiority trials was the strictness of margins from a clinical perspective. Future studies using more recent data, including data on the US Food and Drug Administration, may help in assessing the impact of guideline recommendations on noninferiority margins used for drug approval and may assist in reaching consensus among regulators about the choice of margins.

Tradition, not science, is the basis of animal model selection in translational and applied research

National and international laws and regulations exist to protect animals used for scientific purposes in translational and applied research, which includes drug development. However, multiple animal models are available for each disease. We evaluated the argumentation behind the selection of a specific animal model using thematic content analysis in project applications issued in 2017-2019 in the Netherlands. In total, 125 animal models for translational and applied research from 110 project applications were assessed. Explanations to select a specific model included: the model’s availability (79%); the availability of expertise (62%); and the model showing similar disease pathology/symptoms (59%) to humans. Therefore, current selection of a specific animal model seems to be based on tradition rather than its potential predictive value for clinical outcome. The applicants’ explanations for the implementation of the 3R prin­ciples (replacement, reduction and refinement) as to the animal model were unspecific. Replacement was achieved by using data from prior in vitro studies, reduction by optimal experimental design and statistics, and refinement by reducing discomfort. Additionally, due to the stated need for a test model with high complexity (47%) and intactness (30%), the full replacement of animal models with alternative (non-live animal) approaches was thought unachievable. Without a clear, systematic and transparent justification for the selection of a specific animal model, the likelihood of poorly trans­latable research remains. It is not only up to the researcher to demonstrate this, as ethical committees and funding bodies can provide positive stimuli to drive this change.

Run-in periods and clinical outcomes of antipsychotics in dementia: A meta-epidemiological study of placebo-controlled trials

Purpose

Run‐in periods are used to identify placebo‐responders and washout. Our aim was to assess the association of run‐in periods with clinical outcomes of antipsychotics in dementia.

Methods

We searched randomized placebo‐controlled trials of conventional and atypical antipsychotics for neuropsychiatric symptoms (NPS) in dementia in electronic sources and references of selected articles. We extracted (a) the presence of a run‐in period, use of placebo/investigated drug during run‐in (versus washout only), and run‐in duration (1 week or more) and (b) the reduction in NPS, number of participants with somnolence, extrapyramidal symptoms (EPS), and deaths per treatment group. We pooled clinical outcomes comparing antipsychotic and placebo groups in trials with and without run‐in.

Results

We identified 35 trials. Twenty‐nine trials used run‐in. The pooled standardized mean difference in the reduction of NPS was −0.170 (95% CI, −0.227 to −0.112) in trials with run‐in and −0.142 (95% CI, −0.331 to 0.047) in trials without run‐in. The pooled odds ratio for somnolence was 2.8 (95% CI, 2.3‐3.5) in trials with run‐in and 3.5 (95% CI, 1.2‐10.7) in trials without run‐in; for EPS, these ORs were 1.8 (95% CI, 1.4‐2.2) and 2.0 (95% CI, 1.3‐3.1) respectively, and for mortality 1.4 (95% CI, 1.0‐2.0) and 1.6 (95% CI, 0.7‐3.4). The use of placebo/investigated drug during run‐in and run‐in duration did not affect the estimates in a consistent way.

Conclusions

The use of run‐in in trials might have led to overestimated efficacy and especially underestimated risks of side effects of antipsychotics compared with placebo for NPS in dementia.

Are some animal models more equal than others? A case study on the translational value of animal models of efficacy for Alzheimer's disease

Clinical trial failures (>99%) in Alzheimer's disease are in stark contrast to positive efficacy data in animals. We evaluated the correlation between animal and clinical efficacy outcomes (cognition) in Alzheimer's disease using data from registered drugs as well as interventions tested in phase II or III clinical trials for Alzheimer's disease. We identified 20 interventions, which were tested in 208 animal studies in 63 different animal models. Clinical outcome was correlated with animal results in 58% of cases. But, individual animal models showed divergent results across interventions, individual interventions showed divergent results across animal models, and animal model outcomes were determined with 16 different methods. This result is unsurprising due to poor external validity (what do we model) of the animal models. Although the animal models all share Alzheimer's disease symptoms, none represents the whole syndrome. Investigators did not motivate why one model was chosen over another, and did not consider the ways the disease phenomena were generated (spontaneous, (experimentally) induced or by genetic modification), or the species characteristics, which determine the outcomes. The explanation for the lack of correlation between animal and human outcomes can be manifold: the pathogenesis of Alzheimer's disease is not reflected in the animal model or the outcomes are not comparable. Our conclusion is that currently no animal models exist which are predictive for the efficacy of interventions for Alzheimer's disease.

Alignment of European Regulatory and Health Technology Assessments: A Review of Licensed Products for Alzheimer's Disease

Aims: To facilitate regulatory learning, we evaluated similarities and differences in evidence requirements between regulatory and health technology assessment (HTA) bodies of Alzheimer's disease (AD) approved products. Methods: The European marketing authorisation application dossiers and European public assessment reports (EPARs) of the licensed AD drugs were screened to identify the phase III randomised controlled trials (RCTs) and outcomes used. We also screened the assessment reports of the National Institute of Health and Care Excellence (NICE, England) and the National Health Care Institute (ZiN, the Netherlands) to identify the studies and outcomes used in HTA assessments. Results: The application dossiers of donepezil, galantamine, rivastigmine, and memantine contained 16 phase III RCTs in total. These trials were also included in HTA assessments except that NICE excluded studies that were not published (n = 2) or trials that included patients with other types of dementia (n = 3). In the regulatory assessments the focus was on cognitive and global outcomes, and to some extent on function. In the HTA assessments of clinical effectiveness other domains were also covered including: function, behaviour and mood, and, occasionally, quality of life. In the economic analyses of NICE the domains cognition, function, and quality of life were included. Conclusion: There was a large overlap in inclusion of trials in regulatory and HTA assessments, although the focus on specific outcomes slightly differed. Understanding the methods and perceptions of both authorities can stimulate regulatory and HTA cross-talk and further alignment, and therefore more rapid patient access to new treatments.

Oncologic orphan drugs approved in the EU - do clinical trial data correspond with real-world effectiveness?

BACKGROUND

Evaluation of evidence for efficacy of orphan medicinal products (OMPs) for rare malignancies may be hampered by the use of tumor measurements instead of clinical endpoints. This may cause efficacy data to not always match effectiveness in the real-world. We investigated whether an efficacy-effectiveness gap exists for oncologic OMPs and aimed to identify which factors contribute to it. Also, the magnitude of the clinical efficacy of oncologic OMPs was evaluated.

METHODS

We included all oncologic OMPs authorized in the European Union from 2000 to 2017. Pivotal studies were evaluated by means of the European Society for Medical Oncology - Magnitude of Clinical Benefit Scale (ESMO-MCBS). To estimate real-world effectiveness, a literature search was performed to identify post-marketing studies, of which data on overall survival (OS) were extracted. OS of the new OMP was compared with OS data of standard of care. An OS gain of ≥3 months compared to pre-marketing data was considered clinically relevant.

RESULTS

Twenty OMPs were included, of which 5 were authorized based on OS as a primary endpoint. 10 OMPs had post-marketing data available, of which 40% did not show a clinically relevant OS gain in the real world. All OMPs that were studied with OS as primary endpoint in the pivotal study had a clinically relevant OS gain in the real world. Furthermore, all OMPs that had a high ESMO-MCBS score and post-marketing data available, resulted in a clinically relevant OS gain in the real world.

CONCLUSIONS

Although the sample size is small, our results indicate an efficacy-effectiveness gap for oncologic OMPs exists. Significant changes in PFS do not always lead to an increased OS. The use of PFS may be justified, but validation of surrogate endpoints is needed.

Drug Shortages From the Perspectives of Authorities and Pharmacy Practice in the Netherlands: An Observational Study

Background: Drug shortages are a potential threat to public health. Reliable data on drug shortages is limited. The objective was to examine the extent and nature of potential drug shortages signaled by authorities and pharmacy practice in the Netherlands

Materials and Methods: The primary working systems of Dutch authorities (Medicines Evaluation Board and Health and Youth Care Inspectorate) and the archives of pharmacy practice (Royal Dutch Pharmacists Association) from 2012 to 2015 were searched for number, characteristics, overlap, and date of signals on potential drug shortages. Also, the product characteristics of the potential drug shortages were analyzed from the two different sources

Results: Authorities detected 2.6 times more signals on potential shortages than pharmacy practice. Only 438 (8%) out of 5,731 potential drug shortages were detected by both authorities and pharmacy practice. Signals were detected later by authorities than by pharmacy practice, especially on potential permanent shortages (median difference −180 days (IQR: −4 to −405 days)). Authorities detected by majority (72%) signals related to permanent shortages with relative overrepresentation of rectal products and anti-infectives for systemic use. In contrast, pharmacy practice detected by majority (71%) signals related to temporary shortages with relative overrepresentation of ocular and cutaneous products, anti-infectives for systemic use, products for sensory organs and dermatologicals.

Conclusions: Authorities and pharmacy practice detected different signals on potential drug shortages with little overlap. Combining data from both authorities and pharmacy practice seems to be necessary in order to gain a more complete overview and maximum insight in potential drug shortages at a national level. Moreover, the finding that authorities were informed later than pharmacy practice causes concerns in terms of opportunities for authorities to assist pharmacy practice to find solutions for shortages.

Early Nonresponse in the Antipsychotic Treatment of Acute Mania: A Criterion for Reconsidering Treatment? Results From an Individual Patient Data Meta-Analysis

OBJECTIVE

To investigate whether early nonresponse to antipsychotic treatment of acute mania predicts treatment failure and, if so, to establish the best definition or criterion of an early nonresponse.

DATA SOURCES

Short-term efficacy studies assessing antipsychotics that were submitted to the Dutch Medicines Evaluation Board during an 11-year period as part of the marketing authorization application for the indication of acute manic episode of bipolar disorder. Pharmaceutical companies provided their raw patient data, which enabled us to perform an individual patient data meta-analysis.

STUDY SELECTION

All double-blind, randomized, placebo-controlled trials assessing the efficacy of antipsychotics for acute manic episode of bipolar disorder were included (10 trials).

DATA EXTRACTION

All patients with data available for completer analysis (N = 1,243), symptom severity scores on the Young Mania Rating Scale (YMRS) at weeks 0, 1, and 2 and at study end point (week 3 or 4).

RESULTS

The a priori chances of nonresponse and nonremission at study end point were 40.9% (95% CI, 38.2%-43.6%) and 65.3% (95% CI, 62.0%-68.6%), respectively. Early nonresponse in weeks 1 and 2, defined by cutoff scores ranging from a ≤ 10% to a ≤ 50% reduction in symptoms compared to baseline on the YMRS, significantly predicted nonresponse (≤ 0% symptom reduction) and nonremission (YMRS score higher than 8) in week 3. The predictive value of early nonresponse (PVnr_se) at week 1 for both nonresponse and nonremission at study end point declined linearly with increasing cutoff scores of early nonresponse; nonresponse: 76.0% (95% CI, 69.7%-82.3%) for a ≤ 10% response to 48.7% (95% CI, 45.5%-51.9%) for a ≤ 50% response; nonremission: 92.2% (95% CI, 88.3%-96.1%) for a ≤ 10% response to 76.8% (95% CI, 74.4%-79.5%) for a ≤ 50% response. A similar linear decline was observed for increasing cutoff scores of early nonresponse at week 2 for nonresponse, but not for nonremission at end point: nonresponse 90.3% (95% CI, 84.6%-96.0%) for a ≤ 10% response to 65.0% (95% CI, 61.4%-68.6%) for a ≤ 50% response; nonremission: 94.2% (95% CI, 89.7%-98.7%) for a ≤ 10% response and 93.2% (95% CI, 93.1%-95.1%) for a ≤ 50% response. Specific antipsychotic characteristics did not modify these findings at either time point (week 1: P = .127; week 2: P = .213).

CONCLUSIONS

When patients fail to respond early (1-2 weeks) after the initiation of antipsychotic treatment for acute mania, clinicians should reconsider their treatment choice using a 2-stage strategy.

Drug development for exceptionally rare metabolic diseases: challenging but not impossible

Background

We studied to what extent the level of scientific knowledge on exceptionally rare metabolic inherited diseases and their potential orphan medicinal products is associated with sponsors deciding to apply for an orphan designation at the US Food and Drug Administration (FDA) or the European Medicines Agency (EMA).

Methods

All metabolic diseases with a genetic cause and prevalence of less than 10 patients per 1 million of the population were selected from the ‘Orphanet database of Rare diseases’. The outcome of interest was the application for an orphan designation at FDA or EMA. The level of publicly available knowledge of the disease and drug candidate before an orphan designation application was defined as whether the physiological function corresponding with the pathologic gene and initiation of the pathophysiological pathway was known, whether an appropriate animal study was identified for the disease, whether preclinical proof of concept was ascertained and the availability of data in humans. Other determinants included in the study were metabolic disease class, the prevalence of the disease, prognosis and time of first description of the disease in the literature. Univariate relative risks (RRs) and 95% confidence intervals (CIs) of an orphan designation application were calculated for each of these determinants. In addition, a multivariate Cox regression analysis was conducted (Forward LR).

Results

In total, 166 rare metabolic genetic diseases were identified and included in the analysis. For only 42 (25%) of the diseases an orphan designation application was submitted at either FDA or EMA before January 2012. The multivariate analysis identified preclinical proof of concept of a potential medicinal product as major knowledge related determinant associated with an orphan designation application (RRadj 3.9, 95% CI 1.9-8.3) and confirmed that prevalence of the disease is also associated with filing an application for an orphan designation (RRadj 2.8, 95% CI 1.4-5.4).

Conclusion

For only one out of four known exceptionally rare metabolic inherited diseases sponsors applied for an orphan designation at FDA or EMA. These applications were found to be associated with the prevalence of the rare disease and the level of available scientific knowledge on the proof of concept linking possible drug candidates to the disease of interest.

Immunogenicity of mAbs in non-human primates during nonclinical safety assessment

The immunogenicity of biopharmaceuticals used in clinical practice remains an unsolved challenge in drug development. Non-human primates (NHPs) are often the only relevant animal model for the development of monoclonal antibodies (mAbs), but the immune response of NHPs to therapeutic mAbs is not considered to be predictive of the response in humans because of species differences. In this study, we accessed the drug registration files of all mAbs registered in the European Union to establish the relative immunogenicity of mAbs in NHPs and humans. The incidence of formation of antidrug-antibodies in NHPs and patients was comparable in only 59% of the cases. In addition, the type of antidrug-antibody response was different in NHP and humans in 59% of the cases. Humanization did not necessarily reduce immunogenicity in humans. Immunogenicity interfered with the safety assessment during non-clinical drug development when clearing or neutralizing antibodies were formed. While important to interpret the study results, immunogenicity reduced the quality of NHP data in safety assessment. These findings confirm that the ability to compare relative immunogenicity of mAbs in NHPs and humans is low. Furthermore, immunogenicity limits the value of informative NHP studies.

Impaired neuroendocrine and immune response to acute stress in medication-naive patients with a first episode of psychosis

Little is known about how the biological stress response systems--the autonomic nervous system (ANS), the hypothalamic-pituitary-adrenal (HPA) axis, and the immune system--function during psychosis. Results of studies on the effect of stress on the immune and autonomic system in patients with schizophrenia are inconsistent. The present study investigates whether the stress response is impaired in medication-naive patients with a first episode of psychosis. Ten male patients with a first episode of psychosis and 15 controls were exposed to the stress of public speaking. Parameters of the ANS (heart rate and catecholamines), the HPA axis (plasma adrenocorticotropic hormone [ACTH] and cortisol), and the immune system (number and activity of natural killer [NK] cells) were measured. Peak responses were calculated to examine the relationship between stress-induced activation of the different systems. Subjective stress and anxiety before and during the task were assessed. Patients and controls displayed similar autonomic responses to acute stress. However, there was an impaired HPA axis response, slow onset and return of ACTH, and flattened cortisol response and a reduced increase in number NK cells and NK cell activity in patients with a first episode of psychosis. Furthermore, in patients, the relationship between the different stress response systems was weaker or absent compared with controls. These findings indicate that impairments in stress processing are associated with the endophenotype of psychosis and are not a result of illness progression or antipsychotic medication.

Prescriptive contraceptive use among isotretinoin users in the Netherlands in comparison with non-users: a drug utilisation study

PURPOSE

To assess the compliance with the isotretinoin Pregnancy Prevention Programme (PPP) by evaluating the use of prescribed contraceptives among isotretinoin users. The PPP contains a requirement for the use of contraceptive methods for women of childbearing potential.

METHODS

A drug utilisation study was performed using data from a drug prescription database (containing Dutch community pharmacy data) covering a population of 500 000 patients. Contraceptive use in female isotretinoin users and in a reference group of female non-isotretinoin users (aged 15-49 years) was compared using data from 1999 until 2006 in 2-year periods. Descriptive statistics were used.

RESULTS

Of the female isotretinoin users (n = 651), 52%-54% filled prescriptions on contraceptives in strict accordance to the PPP, used before, during, and after discontinuation of isotretinoin, compared with 39%-46% in the reference group. A more liberal approach of a minimum of one prescription for a contraceptive method showed 61%-64% use of contraceptives among isotretinoin users. Similar patterns were seen when data were broken down in age groups. Furthermore, a higher proportion of female patients using isotretinoin prescribed by general practitioners used prescribed contraceptives compared with those receiving isotretinoin by specialists.

CONCLUSION

Compliance with the contraceptive use according to a PPP for a teratogenic drug such as isotretinoin is 52%-64%, which is lower than anticipated. Reasons for the low compliance will need to be clarified before further measures can be taken.

Prevention trials in Alzheimer's disease: an EU-US task force report

Despite enormous financial and scientific efforts, still no approved disease-modifying therapies exist for Alzheimer's disease (AD). During the last decade all Phase III clinical trials on disease modifiers in AD have failed. The dementia stage of AD being probably too late in order to allow for successful disease modification has been identified as a possible culprit that could explain the failure of so many clinical trials. In parallel, a major development in the diagnostic research field of AD was achieved by the recent proposal of new diagnostic criteria for AD, which also specifically incorporate the use of biomarkers as defining criteria for preclinical stages of AD, thus extending the traditional definition of disease to very early stages that may be a more feasible target for various disease modifying therapeutic interventions. This ongoing paradigm shift in AD definition and diagnosis represents a fundamental basis for redefinition of interventional trials in AD, allowing to specifically focus on preventative measures during very early pathophysiologically confirmed stages of disease. This consensus paper reflects the outcome from a European Union and North American Task Force meeting comprised of experts from academia, industry, private foundations, and regulatory agencies that was convened in Toulouse, France on November 5, 2010 and that focused on prevention trials in AD. This position paper thoroughly analyzes prerequisites for successful preventative trials in AD and concludes with concrete recommendations on biomarkers, statistical tools and other variables important for improved study designs suitable for preventative as well as for early therapeutic interventional trials in AD.

Autonomic and Neuroendocrine Responses to a Psychosocial Stressor in Adults with Autistic Spectrum Disorder

Objective of the study was to replicate in adults our previous findings of decreased heart rate and normal endocrine responses to stress in autistic children and to elucidate the discrepancy between autonomic and endocrine stress responses by including epinephrine, norepinephrine, oxytocin and vasopressin measurements. Ten autistic spectrum disorder (ASD) adults were compared to 14 healthy controls in their response to a psychosocial stressor (public speaking). ASD patients showed decreased heart rate, but normal cortisol responses, consistent with our prior findings in children. No differences in norepinephrine, epinephrine, oxytocin or vasopressin responses to stress were found. However, in contrast to previous findings in low functioning autistic children, ASD adults showed increased basal oxytocin levels, which may be related to developmental factors.

Hyperglycemia and diabetes in patients with schizophrenia or schizoaffective disorders

OBJECTIVE

Pharmacoepidemiological studies have shown an increased prevalence of diabetes in patients with schizophrenia. To address this issue, we decided to assess glucose metabolism in a population of patients with schizophrenia or schizoaffective disorder.

RESEARCH DESIGN AND METHODS

Oral glucose tolerance tests (OGTTs) were performed in 200 unselected in- and outpatients. Insulin sensitivity and beta-cell function were assessed using the homeostasis model assessment (HOMA) indexes and 30-min glucose and insulin levels.

RESULTS

The mainly Western European (87.7%) study population had a mean age of 40.8 years, was 70% male, and had a mean fasting glucose of 5.1 mmol/l and a mean fasting insulin of 14.8 mU/l. Hyperglycemia was present in 7% of the population: 1.5% with impaired fasting glucose and 5.5% with impaired glucose tolerance. The prevalence of diabetes was 14.5%, of which 8% was previously known and 6.5% was newly diagnosed. Compared with a 1.5% prevalence of diabetes in the age-matched general Dutch population, the prevalence of identified cases was significantly increased in the study population. Comparable figures on the prevalence of hyperglycemia in the general population are not available. Insulin resistance was increased in the study population as a whole (HOMA of insulin resistance: 3.1-3.5), irrespective of the use of antipsychotic medication and, if used, irrespective of its type (typical or atypical). No indication of beta-cell defect was found, whereas a nonsignificant increased insulin resistance was found with antipsychotic medication.

CONCLUSIONS

OGTTs in 200 mainly Caucasian patients with schizophrenia or schizoaffective disorder, mean age 41 years, showed that 7% suffered from hyperglycemia and 14.5% from diabetes. The prevalence of diabetes was significantly increased compared with the general population. No differential effect of antipsychotic monotherapy in diabetogenic effects was found. Therefore, a modification of the consensus statement on antipsychotic drugs, obesity, and diabetes is proposed, i.e., measurement of fasting glucose in all patients with schizophrenia, irrespective of prescribed antipsychotic drug.

Antidepressants use in children and adolescents and the risk of suicide

OBJECTIVE

Antidepressants use in paediatric patients has been linked with risk of suicidal behaviours. The aim of this paper, therefore, is to examine whether all antidepressants are associated with such risk.

METHOD

All 22 paediatric short-term placebo-controlled trials of SSRIs and NSRIs that were submitted to European registration authorities by pharmaceutical companies were identified and examined for events related to suicidality, which were defined as suicide, suicide attempts or suicidal thoughts. Random effect meta-analysis was used to combine the information from all trials.

RESULTS

No completed suicides were reported. However, for each compound there was at least one study with an increased risk for events related to suicidality in the active compound group. The overall OR for these events in the depression studies was 1.67 (95% CI: 1.05-2.65) and for anxiety 1.33 (95% CI: 0.33-5.35).

CONCLUSIONS

Caution is called for in the use of all SSRIs and NSRIs in the paediatric population. Furthermore, in the absence of contradictory information, caution in the use of other antidepressants in this population should be exercised as well (e.g. tricyclic antidepressants).

Suicide risk in placebo-controlled trials of treatment for acute manic episode and prevention of manic-depressive episode

OBJECTIVE

The authors' goal was to investigate whether there is a greater suicide risk in the placebo arms of placebo-controlled studies of active medication for the treatment of acute manic episode and the prevention of manic/depressive episode. If so, this would be a strong ethical argument against the conduct of such studies.

METHOD

All placebo-controlled, double-blind, randomized trials of medication for the treatment of acute manic episode and the prevention of manic/depressive episode that were part of a registration dossier submitted to the regulatory authority of the Netherlands, the Medicines Evaluation Board, between 1997 and 2003, were reviewed for occurrence of suicide and attempted suicide.

RESULTS

In 11 placebo-controlled studies of the treatment of acute manic episode, including 1,506 patients (117 person-years) in the combined active compound group and 1,005 patients (71 person-years) in the combined placebo group, no suicides and no suicide attempts occurred. In four placebo-controlled studies of the prevention of manic/depressive episode, including 943 patients (406 person-years) in the combined active compound group and 418 patients (136 person-years) in the combined placebo group, two suicides (493/100,000 person-years of exposure) and eight suicide attempts (1,969/100,000 person-years of exposure) occurred in the combined active compound group, but no suicides and two suicide attempts (1,467/100,000 person-years of exposure) occurred in the combined placebo group.

CONCLUSIONS

Concern about greater risk of suicide or attempted suicide in the placebo group should not be an argument against the conduct of placebo-controlled trials for these indications, provided that appropriate precautions are taken.

How real are patients in placebo-controlled studies of acute manic episode?

OBJECTIVE

To determine whether the results from placebo-controlled studies conducted in patients with manic episode can be generalised to a routine population of hospitalised acute manic patients.

METHODS

A list of four most prevalent inclusion and the nine most prevalent exclusion criteria was constructed for participation in previous randomised-controlled trials (RCTs). On the basis of this list, a consecutive series of 68 patients with 74 episodes of acute mania who had been referred for routine treatment were retrospectively assessed to determine their eligibility for a hypothetical but representative randomised controlled trial.

RESULTS

Only 16% of the manic episodes would qualify for the hypothetical trial (male episodes 28%, female episodes 10%), whereas 37%, 20% and 27% of the manic episodes would have to be excluded because they did no fulfil one, two or at least three of the inclusion or exclusion criteria. The most common exclusion criterion was "no use of contraceptives". If this criterion was not taken into account, 28% of the male episodes and 33% of the female episodes would qualify for inclusion in the hypothetical study. Apart from the use of contraceptives, no significant differences between male and female episodes were observed in the reasons for exclusion: 11% suicidal ideation, 29% prior mood stabilising medication, 1% depot medication, 22% other axis I diagnosis, 27% internal disease somatic disease, 5% neurological disorder, 15% alcohol use disorder and 10% drug use disorder.

CONCLUSION

Only a small percentage acute manic episodes in a routine mental hospital seem to qualify for a standard placebo-controlled RCT. It could be argued, however, that certain exclusion criteria (e.g. no use of contraceptives) are not very likely to reduce the external validity of a standard RCT. In contrast, some other exclusion criteria (e.g. comorbid alcohol and drug use disorders) may have resulted in an overestimation of the efficacy of anti-manic medications. These notions should be taken into account when evaluating the results of RCTs in bipolar patients with an acute manic episode.

Differentiation between autism and multiple complex developmental disorder in response to psychosocial stress

Multiple Complex Developmental Disorder (MCDD) represents a distinct group within the autistic spectrum based on symptomatology. Unlike autistic children, part of MCDD children develop schizophrenia in adult life. Despite the differences, patients of both disorders are mainly characterized by abnormal reactions to their social environment. At the biological level, we showed in a previous study that MCDD children have a reduced cortisol response to psychosocial stress. Given the fact that autistic children clinically show more social impairments, it was hypothesized that they may have even further decreased cortisol responses to psychosocial stress than MCDD patients. Therefore, 10 autistic children were compared to 10 MCDD children and 12 healthy control children in their response to a psychosocial stressor, consisting of a public speaking task. In order to test whether any impairments in the biological stress response are specific for psychosocial stress, the autistic children were compared with 11 MCDD children and 15 control children in their response to a physical stressor, consisting of 10 min of bicycle exercise. Heart rate and salivary cortisol levels were used as indicators of response to the stress tests. Autistic children showed a relatively elevated cortisol response to psychosocial stress, in contrast to MCDD children who showed a reduced cortisol response. No differences in heart rate or cortisol responses to the physical stress test were found. The specific difference between autistic and MCDD children in their cortisol response to psychosocial stress indicates that the disturbed reactions to the social environment observed in these disorders may have different biological backgrounds.

Modulating sensory gating in healthy volunteers: the effects of ketamine and haloperidol

BACKGROUND

Antagonists of the N-methyl-D-aspartate (NMDA) receptors induce a broad range of psychophysiologic symptoms in healthy subjects that are similar to those of schizophrenia, such as disturbances in the sensory gating of stimuli. Because antipsychotics reduce symptoms in schizophrenia, they may also reduce the effects of NMDA antagonists.

METHODS

In our study, a group of 18 healthy male volunteers was tested in prepulse inhibition (PPI) and P50 evoked potential paradigms during placebo-placebo, placebo-ketamine (.3 mg/kg; intravenous), and 2-mg haloperidol/.3 mg/kg intravenous ketamine conditions.

RESULTS

Suppression of PPI and P50 in the ketamine condition did not differ from either the placebo-placebo or the haloperidol-ketamine condition; however, a significant reduction in percentage PPI to the lowest prepulse intensity and a reduction of P50 suppression were found in the haloperidol-ketamine condition.

CONCLUSIONS

The combination of haloperidol and ketamine was found to disrupt P50 suppression and PPI in healthy male volunteers, whereas ketamine alone did not affect either measure. This may imply that the disrupted P50 suppression and PPI found in schizophrenia is related to reduced dopaminergic activity, most likely in the prefrontal cortex.

The stress-vulnerability hypothesis in psychotic disorders: focus on the stress response systems

The vulnerabilty stress model is an intriguing concept to look into the etiology of psychotic disorders and, in particular, into the "nature nurture" principle. That stress affects a vulnerable nature may be obvious, but its mechanism is not well understood, and many questions remain to be answered, let alone how to define "vulnerability". The present review tries to focus on the core issues of the vulnerability stress concept--identifying vulnerability, the way stress interferes with it, and the possiblilities of modulating their interaction. Attention is drawn to the biologic stress response systems, the autonomic nervous system (ANS), the hypothalamic pituitary adrenal (HPA) system, and the immune system, and highlights the plasticity of the HPA system as the mediator of adaptation.