Differential effects of antipsychotic and antidepressant drugs on neurogenic regions in rats

Increased neurogenesis in the hippocampus and subventricular zone (SVZ) of the brain of animals has been demonstrated following administration of several psychotropic medications. Such changes are thought to regenerate tissues and contribute to the beneficial effects of the medications. This study sought to determine if another neurogenic tissue, the peripheral olfactory epithelium (OE), might also exhibit changes after treatment with psychotropic medications. Young adult male rats were treated with risperidone and paliperidone, atypical antipsychotic medications; fluoxetine, a selective serotonin reuptake inhibitor (SSRI) antidepressant; and diluent control for 28days via drinking water. Bromodeoxyuridine (BrdU) was injected to label dividing cells and positive cells were quantified in the OE, cortical SVZ, and dentate gyrus (DG) of the hippocampus. In the first of two studies, paliperidone and risperidone treatment (at 1mg/kg/day) resulted in increased numbers over controls of BrdU positive cells in the OE. In the second study, examining OE, SVZ and DG in the same animal, paliperidone, but not risperidone or fluoxetine (0.6 mg/kg/day) resulted in increased cells in the OE and posterior SVZ. However, fluoxetine, but not paliperidone or risperidone treatment increased BrdU positive cells in the DG. These results show that psychotropic drug-induced cell proliferation occurs in the OE and parallels changes in the SVZ but not DG. Thus, the peripheral OE can serve as a proxy for certain psychotropic drug-induced actions on SVZ brain cell proliferation. This olfactory model can be employed in human research as a method to explore the neurogenesis effects of various pharmacologic treatments of neuropsychiatric disorders.

Inflammatory markers in schizophrenia: comparing antipsychotic effects in phase 1 of the clinical antipsychotic trials of intervention effectiveness study

BACKGROUND

C-reactive protein (CRP), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin are systemic inflammatory markers (IM) that positively correlate with cardiovascular (CV) risk. Despite the known CV effects of atypical antipsychotics, there is limited prospective data on IM changes during treatment.

METHODS

The IM outcomes were compared between antipsychotic treatment groups in the CATIE (Clinical Antipsychotic Trials of Intervention Effectiveness) schizophrenia trial phase 1 with subjects with laboratory assessments at baseline and 3 months (n = 789).

RESULTS

There were significant treatment differences in CRP, E-selectin, and ICAM-1 at 3 months, with a differential impact of baseline values on the CRP and ICAM-1 results. In overall comparisons, quetiapine and olanzapine had the highest median levels for CRP, and olanzapine for E-selectin and ICAM-1. Olanzapine was significantly different after baseline adjustment than perphenazine (p = .001) for E-selectin, and in those with low baseline CRP (<1 mg/L), olanzapine was significantly different than perphenazine (p < .001), risperidone (p < .001), and ziprasidone (p = .002) for CRP. Perphenazine had the lowest 3-month ICAM-1 levels in subjects with baseline ICAM-1 above the median, but the differences were not statistically significant versus olanzapine (p = .010), quetiapine (p = .010), and risperidone (p = .006) after controlling for multiple comparisons. The 18-month repeated measures CRP analysis confirmed the significantly higher values for olanzapine in those with low baseline CRP.

CONCLUSIONS

This analysis provides further evidence for differential antipsychotic metabolic liabilities as measured by changes in systemic inflammation. C-reactive protein might emerge as a useful target for CV risk outcomes in schizophrenia patients.

Neurological disorders in schizophrenia

Schizophrenia (SZ) is a complex, heterogeneous, and disabling psychiatric disorder that impairs multiple aspects of human cognitive, perceptual, emotional, and behavioral functioning. SZ is relatively frequent (prevalence around 1%), with onset usually during adolescence or early adulthood, and has a deteriorating course. The rapidly growing area of neuroimaging research has has found clear evidence of many cortical and subcortical abnormalities in individuals with SZ. In this article the most recent findings from multiple studies on neurological disorders in SZ are reviewed, and the authors make a strong argument for a neurological basis of the schizophrenic process.

Schizophrenia, "just the facts" 4. Clinical features and conceptualization

Although dementia praecox or schizophrenia has been considered a unique disease entity for the past century, its definitions and boundaries have continued to vary over this period. At any given time, the changing concept of schizophrenia has been influenced by available diagnostic tools and treatments, related conditions from which it most needs to be distinguished, extant knowledge and scientific paradigms. There is significant heterogeneity in the etiopathology, symptomatology, and course of schizophrenia. It is characterized by an admixture of positive, negative, cognitive, mood, and motor symptoms whose severity varies across patients and through the course of the illness. Positive symptoms usually first begin in adolescence or early adulthood, but are often preceded by varying degrees of negative and cognitive symptomatology. Schizophrenia tends to be a chronic and relapsing disorder with generally incomplete remissions, variable degrees of functional impairment and social disability, frequent comorbid substance abuse, and decreased longevity. Although schizophrenia may not represent a single disease with a unitary etiology or pathogenetic process, alternative approaches have thus far been unsuccessful in better defining this syndrome or its component entities. The symptomatologic, course, and etio-pathological heterogeneity can usefully be addressed by a dimensional approach to psychopathology, a clinical staging approach to illness course, and by elucidating endophenotypes and markers of illness progression, respectively. This will allow an approach to the deconstruction of schizophrenia into its multiple component parts and strategies to reconfigure these components in a more meaningful manner. Possible implications for DSM-V and ICD-11 definitions of schizophrenia are discussed.

Proceedings and data from The Schizophrenia Summit: a critical appraisal to improve the management of Schizophrenia

In mid-February 2008, a panel of 10 nationally recognized schizophrenia research experts was assembled in a Schizophrenia Summit to focus on controversies that exist in treating patients with schizophrenia. The current literature related to the diagnosis and etiopathology of schizophrenia was evaluated regarding the identification of a prodromal phase, brain changes, cognitive impairments, genetic factors, and use of neuroimaging in patients with schizophrenia. Further, consideration was given to evidence supporting the neuroprotective benefits of atypical antipsychotic medications, the benefits of treating patients during the prodromal period, the use of combination antipsychotic medications, the need to improve cognitive function, and the management of substance abuse. Summit faculty member opinion is compared with field survey results, and recommendations are made for future research.

An analysis of the high psychotropic off-label use in psychiatric disorders The majority of psychiatric diagnoses have no approved drug

OBJECTIVE

The authors' goals were to determine the extent of unapproved indications in the DSM-IV-TR, to highlight common off-label uses of psychotropic medications and offer insights into the rationale of the widespread off-label prescribing in psychiatry.

METHOD

Indications for approved psychotropic agents, obtained from the Physicians Desk Reference and the Drug Information Handbook, Clinical Handbook of Psychotropic Drugs, 15th edition, and the Drugs@FDA online database were analyzed in the context of the DSM-IV-TR to determine the percent of DSM-IV-TR disorders that are indications for psychotropic agents. A literature search was performed to determine common off-label uses of major classes of psychotropic medications.

RESULTS

88.5% of all DSM-IV-TR categorized disorders lack an approved medication for their treatment. Atypical Antipsychotics had the most extensive off-label use for DSM-IV-TR categorized disorder, whereas Mood Stabilizers showed the greatest off-label use with regards to disorders and symptoms that are not DSM-IV classified. For each class of medications, more off-label uses exist than FDA-approved uses.

CONCLUSIONS

The vast majority of DSM-IV-TR categorized disorders lack approved medications for their treatment. The large unmet need for approved psychiatric indications may explain the widespread off-label use of psychotropic medications in clinical practice.

Schizophrenia, "just the facts": what we know in 2008 Part 3: neurobiology

Investigating the neurobiological basis of schizophrenia is a critical step toward establishing its diagnostic validity, predicting outcome, delineating causative mechanisms and identifying objective targets for treatment research. Over the past two decades, there have been several advances in this field, principally related to developments in neuroimaging, electrophysiological and neuropathological approaches. Several neurobiological alterations in domains of brain structure, physiology and neurochemistry have been documented that may reflect diverse pathophysiological pathways from the "genome to the phenome". While none of the observed abnormalities are likely to qualify as diagnostic markers at this time, many can serve as potential intermediate phenotypes for elucidating etiological factors including susceptibility genes, and as therapeutic targets for novel drug discovery. Despite several challenges including the substantial phenotypic, pathophysiologic and etiological heterogeneity of schizophrenia, technological limitations, and the less than ideal animal models, considerable progress has been made in characterizing the neurobiological substrate of schizophrenia. The accumulating fact-base on the neurobiology of schizophrenia calls for novel integrative model(s) that may generate new, testable predictions.

Temporal sequence of clinical manifestation in schizophrenia with co-morbid OCD: review and meta-analysis

Obsessive-compulsive disorder (OCD) is often a comorbidity in schizophrenia (SCZ), but little is known about whether OCD emerges before or after a diagnosis of SCZ in the absence of atypical antipsychotic medications. The authors analyzed data from clinical studies reporting the temporal sequence of OCD and SCZ in comorbid patients to determine if there was a significant statistical difference between the mean ages of onset in both disorders and the percentage of patients diagnosed with OCD before SCZ. A MEDLINE search was conducted using the keywords "OCD" and "Schizophrenia." Studies were assessed for the presence of data regarding the ages of onset of patients comorbid with both disorders as well as the number of patients in each study diagnosed with OCD first, SCZ first, or both disorders concurrently. A meta-analysis was performed to test the a priori hypothesis that OCD is diagnosed before SCZ in patients who are comorbid with both disorders. There was no statistically significant difference in the unstandardized difference in the mean age of onset of OCD and SCZ. A strong trend in the data exists suggesting that the onset of OCD precedes SCZ. Future prospective studies with larger sample sizes are warranted.

Antipsychotic effects on estimated 10-year coronary heart disease risk in the CATIE schizophrenia study

OBJECTIVE

Persons with schizophrenia die earlier than the general population, in large part due to cardiovascular disease. The study objective was to examine effects of different antipsychotic treatments on estimates of 10-year coronary heart disease (CHD) risk calculated by the Framingham Heart Study formula.

METHOD

Change in 10-year risk for CHD was compared between treatment groups in 1125 patients followed for 18 months or until treatment discontinuation in the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) Schizophrenia Trial.

RESULTS

The covariate-adjusted mean change in 10-year CHD risk differed significantly between treatments. Olanzapine was associated with a 0.5% (SE 0.3) increase and quetiapine, a 0.3% (SE 0.3) increase; whereas risk decreased in patients treated with perphenazine, -0.5% (SE 0.3), risperidone, -0.6% (SE 0.3), and ziprasidone -0.6% (SE 0.4). The difference in 10-year CHD risk between olanzapine and risperidone was statistically significant (p=0.004). Differences in estimated 10-year CHD risk between drugs were most marked in the tertile of subjects with a baseline CHD risk of at least 10%. Among individual CHD risk factors used in the Framingham formula, only total and HDL cholesterol levels differed between treatments.

CONCLUSIONS

These results indicate that the impact on 10-year CHD risk differs significantly between antipsychotic agents, with olanzapine producing the largest elevation in CHD risk of the agents studied in CATIE.

Impact of antipsychotic treatment on nonfasting triglycerides in the CATIE Schizophrenia Trial phase 1

BACKGROUND

Recent literature documents a stronger association between nonfasting triglycerides (TG) and cardiovascular risk compared to fasting TG. Given concerns over antipsychotic effects on serum TG, this analysis explored changes in nonfasting TG in phase 1 of the CATIE Schizophrenia Trial.

METHODS

Change in nonfasting TG, adjusted for baseline value, was compared between antipsychotic treatment groups using subjects with nonfasting laboratory assessments at baseline and 3 months.

RESULTS

Among the 246 subjects there were significant treatment differences in 3-month change from baseline (p=0.009). The greatest increases in median and adjusted mean nonfasting TG levels were seen among those randomized to quetiapine (mean+54.7 mg/dl, median+26 mg/dl) and olanzapine (mean+23.4 mg/dl, median+26.5 mg/dl), while ziprasidone was neutral (mean+0.0 mg/dl, median+8 mg/dl), and decreases were seen with risperidone (mean -18.4 mg/dl, median -6.5 mg/dl) and perphenazine (mean -1.3 mg/dl, median -22 mg/dl). Pairwise comparisons indicated a significant between-group difference for perphenazine vs. olanzapine (p=0.002) and a trend for perphenazine vs. quetiapine (p=0.006).

CONCLUSIONS

This analysis provides further evidence for differential antipsychotic metabolic liabilities, and confirms signals for the effects of olanzapine and quetiapine on serum TG seen in earlier CATIE analyses. Future consensus recommendations will clarify the role of nonfasting TG monitoring in routine clinical practice.

Schizophrenia, "just the facts" what we know in 2008. 2. Epidemiology and etiology

Although we have studied schizophrenia as a major disease entity over the past century, its causes and pathogenesis remain obscure. In this article, we critically review genetic and other epidemiological findings and discuss the insights they provide into the causes of schizophrenia. The annual incidence of schizophrenia averages 15 per 100,000, the point prevalence averages approximately 4.5 per population of 1000, and the risk of developing the illness over one's lifetime averages 0.7%. Schizophrenia runs in families and there are significant variations in the incidence of schizophrenia, with urbanicity, male gender, and a history of migration being associated with a higher risk for developing the illness. Genetic factors and gene-environment interactions together contribute over 80% of the liability for developing schizophrenia and a number of chromosomal regions and genes have been "linked" to the risk for developing the disease. Despite intensive research and spectacular advances in molecular biology, however, no single gene variation has been consistently associated with a greater likelihood of developing the illness and the precise nature of the genetic contribution remains obscure at this time. Environmental factors linked to a higher likelihood of developing schizophrenia include cannabis use, prenatal infection or malnutrition, perinatal complications, and a history of winter birth; the exact relevance or nature of these contributions is, however, unclear. How various genetic and environmental factors interact to cause schizophrenia and via which precise neurobiological mechanisms they mediate this effect is not understood. Etiological heterogeneity, complex patterns of gene-gene and gene-environment interaction, and inadequately elucidated schizophrenia pathophysiology are among the explanations invoked to explain our inadequate understanding of the etio-pathogenesis of schizophrenia. The ability to question some of our basic assumptions about the etiology and nature of schizophrenia and greater rigor in its study appear critical to improving our understanding about its causation.

Change in metabolic syndrome parameters with antipsychotic treatment in the CATIE Schizophrenia Trial: prospective data from phase 1

BACKGROUND

The metabolic syndrome (MS) is associated with increased risk for diabetes mellitus and coronary heart disease, and is highly prevalent among schizophrenia patients. Given concerns over antipsychotic metabolic effects, this analysis explored MS status and outcomes in phase 1 of the CATIE Schizophrenia Trial.

METHODS

The change in proportion of subjects with MS and individual criteria was compared between antipsychotic treatment groups, along with mean changes for individual criteria. Primary analyses examined subjects with fasting laboratory assessments at baseline and 3 months. Other analyses examined 3-month changes in MS status, waist circumference (WC), HDL cholesterol and blood pressure in all subjects, metabolic changes at the end of phase 1 participation (EOP), and repeated measures changes in HDL, blood pressure (BP) and WC over phase 1.

RESULTS

At 3 months, there were no significant between-drug differences for the change in proportion of subjects meeting MS status or individual MS criteria in the smaller fasting cohort (n = 281) or for those meeting criteria for parameters not dependent on fasting status (BP, HDL, WC) among all subjects (n=660). Among all subjects whose MS status could be determined at 3 months (n=660), MS prevalence increased for olanzapine (from 34.8% to 43.9%), but decreased for ziprasidone (from 37.7% to 29.9%) (p=.001). Although effect sizes varied across subgroups, at 3 months olanzapine and quetiapine had the largest mean increase in waist circumference (0.7 in. for both) followed by risperidone (0.4 in.), compared to no change for ziprasidone (0.0 in.) and a decrease in waist circumference for perphenazine (-0.4 in.). Olanzapine also demonstrated significantly different changes in fasting triglycerides at 3 months (+21.5 mg/dl) compared to ziprasidone (-32.1 mg/dl). EOP exposure data was obtained, on average, nine months from baseline for all metabolic variables. Results from EOP and repeated measures analyses were consistent with those at 3 months for mean changes in WC and fasting triglycerides, but between group differences emerged for HDL and SBP.

CONCLUSIONS

This large non-industry sponsored study confirms the differential metabolic effects between antipsychotics. Clinicians are advised to monitor all metabolic parameters, including WC, HDL and serum triglycerides, during antipsychotic treatment.

Atypical antipsychotic-induced metabolic side effects: insights from receptor-binding profiles

Atypical antipsychotic drugs offer several notable benefits over typical antipsychotics, including greater improvement in negative symptoms, cognitive function, prevention of deterioration, and quality of life, and fewer extrapyramidal symptoms (EPS). However, concerns about EPS have been replaced by concerns about other side effects, such as weight gain, glucose dysregulation and dyslipidemia. These side effects are associated with potential long-term cardiovascular health risks, decreased medication adherence, and may eventually lead to clinical deterioration. Despite a greater understanding of the biochemical effects of these drugs in recent years, the pharmacological mechanisms underlying their various therapeutic properties and related side effects remain unclear. Besides dopamine D(2) receptor antagonism, a characteristic feature of all atypical antipsychotic drugs, these agents also bind to a range of non-dopaminergic targets, including serotonin, glutamate, histamine, alpha-adrenergic and muscarinic receptors. This review examines the potential contribution of different receptors to metabolic side effects associated with atypical antipsychotic treatment for all seven agents currently marketed in the United States (risperidone, olanzapine, quetiapine, ziprasidone, aripiprazole, paliperidone and clozapine) and another agent (bifeprunox) in clinical development at the time of this publication.

Improving the pedagogy associated with the teaching of psychopharmacology

OBJECTIVE

The authors summarize two special sessions focused on the teaching of psychopharmacology at the 2003 and 2004 annual meeting of the American College of Neuropsychopharmacology (ACNP). The focus was on whether "improving the teaching-learning process" in psychiatric residency programs could improve clinical practice.

METHOD

Problems of strategies and pedagogic techniques that have been used were presented from multiple perspectives (e.g., from a dean, department chair, training director, and former students).

CONCLUSIONS

There was a consensus that action involving psychopharmacology organizations and the American Association of Directors of Residency Training in Psychiatry (AADPRT) was necessary to improve "evidence-based" competencies before graduation and to follow prescribing patterns into clinical practice to determine whether the standards of care could be improved.

The case for long-acting antipsychotic agents in the post-CATIE era

OBJECTIVE

Long-acting antipsychotic agents were developed to promote treatment compliance in patients requiring maintenance treatment for schizophrenia.

METHOD

An analysis of the impact of non-compliance on treatment outcomes in schizophrenia and the advantages and disadvantages of long-acting antipsychotics.

RESULTS

Partial or total non-compliance with oral antipsychotics remains widespread and is associated with significant increases in the risk of relapse, rehospitalization, progressive brain tissue loss and further functional deterioration. Long-acting agents have the potential to address issues of all-cause discontinuation and poor compliance. The development of the first long-acting atypical antipsychotic, which appears to be effective and well tolerated, should further improve the long-term management of schizophrenia.

CONCLUSION

Long-acting agents represent a valuable tool for the management of schizophrenia and merit wider use, especially in light of emerging literature regarding the neuroprotective advantages of atypical antipsychotics over conventional agents in terms of regenerating brain tissue during maintenance therapy.

The roles of efficacy, safety, and tolerability in antipsychotic effectiveness: practical implications of the CATIE schizophrenia trial

The Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) series of studies has set a standard for trials in schizophrenia. Included in the 3-phase National Institute of Mental Health-sponsored series were 1460 patients drawn from 57 sites in 24 states. This was designed as a "real-world" practical clinical trial, including a broad array of patients and asking straightforward, clinically relevant questions. The primary aim was to compare the available atypical agents olanzapine, quetiapine, risperidone, and ziprasidone-to each other and to the typical agent perphenazine-with regard to drug effectiveness and tolerability. In general, the various agents studied were similar, with olanzapine being relatively the most effective, as measured by treatment discontinuation. This might be due in part to the more optimal dosing of olanzapine compared with the other antipsychotics. In the study arm that included clozapine, that agent was shown to be more effective than olanzapine, quetiapine, or risperidone. Perphenazine tended to perform as well as the atypical agents. Except for clozapine, olanzapine clearly had the greatest metabolic side effect burden, and ziprasidone, the least. Perphenazine had the most motor side effects, although the rate was modest.