John K. Hsiao

Prevalence of the metabolic syndrome in patients with schizophrenia: baseline results from the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) schizophrenia trial and comparison with national estimates from NHANES III.

UNLABELLED One important risk factor for cardiovascular disease is the metabolic syndrome (MS), yet limited data exist on its prevalence in US patients with schizophrenia. METHODS Using baseline data from the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) Schizophrenia Trial, assessment of MS prevalence was performed based on National Cholesterol Education Program (NCEP) criteria, and also using a fasting glucose threshold of 100 mg/dl (AHA). Subjects with sufficient anthropometric data, data on use of antihypertensives, hypoglycemic medications or insulin, and fasting glucose and lipid values >8 h from last meal were included in the analysis. Comparative analyses were performed using a randomly selected sample from NHANES III matched 1:1 on the basis of age, gender and race/ethnicity. RESULTS Of 1460 CATIE baseline subjects, 689 met analysis criteria. MS prevalence was 40.9% and 42.7%, respectively using the NCEP and AHA derived criteria. In females it was 51.6% and 54.2% using the NCEP and AHA criteria, compared to 36.0% (p = .0002) and 36.6% (p = .0003), respectively for males. 73.4% of all females (including nonfasting subjects) met the waist circumference criterion compared to 36.6% of males. In a logistic regression model with age, race and ethnicity as covariates, CATIE males were 138% more likely to have MS than the NHANES matched sample, and CATIE females 251% more likely than their NHANES counterparts. Even when controlling for differences in body mass index, CATIE males were still 85% more likely to have MS than the NHANES male sample, and CATIE females 137% more likely to have MS than females in NHANES. CONCLUSIONS The metabolic syndrome is highly prevalent in US schizophrenia patients and represents an enormous source of cardiovascular risk, especially for women. Clinical attention must be given to monitoring for this syndrome, and minimizing metabolic risks associated with antipsychotic treatment.

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.

Clinical Symptom Responses to Atypical Antipsychotic Medications in Alzheimer’s Disease: Phase 1 Outcomes from the CATIE-AD Effectiveness Trial

OBJECTIVE The study measured the effects of atypical antipsychotics on psychiatric and behavioral symptoms in patients with Alzheimers disease and psychosis or agitated behavior. METHOD The Clinical Antipsychotic Trials of Intervention Effectiveness-Alzheimers Disease (CATIE-AD) Alzheimers disease effectiveness study included 421 outpatients with Alzheimers disease and psychosis or agitated/aggressive behavior. Patients were assigned randomly to masked, flexible-dose treatment with olanzapine, quetiapine, risperidone, or placebo for up to 36 weeks. Patients could be randomly reassigned to a different medication at the clinicians discretion, which ended phase 1. Psychiatric and behavioral symptoms, functioning, cognition, care needs, and quality of life were measured at regular intervals. RESULTS In relation to placebo, the last observation in phase 1 showed greater improvement with olanzapine or risperidone on the Neuropsychiatric Inventory total score, risperidone on the Clinical Global Impression of Changes, olanzapine and risperidone on the Brief Psychiatric Rating Scale (BPRS) hostile suspiciousness factor, and risperidone on the BPRS psychosis factor. There was worsening with olanzapine on the BPRS withdrawn depression factor. Among patients continuing phase 1 treatment at 12 weeks, there were no significant differences between antipsychotics and placebo on cognition, functioning, care needs, or quality of life, except for worsened functioning with olanzapine compared to placebo. CONCLUSION In this descriptive analysis of outpatients with Alzheimers disease in usual care settings, some clinical symptoms improved with atypical antipsychotics. Antipsychotics may be more effective for particular symptoms, such as anger, aggression, and paranoid ideas. They do not appear to improve functioning, care needs, or quality of life.

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.

National Institute of Mental Health Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE): Alzheimer Disease Trial Methodology

The authors describe the development of the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) protocol for Alzheimer disease (AD), a trial developed in collaboration with the National Institute of Mental Health (NIMH), assessing the effectiveness of atypical antipsychotics for psychosis and agitation occurring in AD outpatients. They provide an overview of the methodology utilized in the trial as well as the clinical-outcomes and effectiveness measures that were implemented.

Quantitative Examination of Tissue Concentration Profiles Associated with Microdialysis

Abstract: Spatial solute concentration profiles resulting from in vivo microdialysis were measured in rat caudate‐putamen by quantitative autoradiography. Radiolabeled sucrose was included in the dialysate, and the tissue concentration profile measured after infusions of 14 min and 61.5 min in an acute preparation. In addition, the changes in sucrose extraction fraction over time were followed in vivo and in a simple in vitro system consisting of 0.5% agarose. These experimental results were then compared with mathematical simulations of microdialysis in vitro and in vivo. Simulations of in vitro microdialysis agreed well with experimental results. In vivo, the autoradiograms of the tissue concentration profiles showed clear evidence of substantial differences between 14 and 61.5 min, even though the change in extraction fraction was relatively small over that period. Comparison with simulated results showed that the model substantially underpre‐dicted the observed extraction fraction and overall amount of sucrose in the tissue. A sensitivity analysis of the various model parameters suggested a tissue extracellular volume fraction of approximately 40% following probe implantation. We conclude that the injury from probe insertion initially causes disruption of the blood‐brain barrier in the vicinity of the probe, and this disruption leads to an influx of water and plasma constituents, causing a vasogenic edema.

Effects of Different Semipermeable Membranes on In Vitro and In Vivo Performance of Microdialysis Probes

The in vitro and in vivo performance of three different semipermeable microdialysis membranes was compared: a proprietary polycarbonate‐ether membrane made by Carnegie Medecin; cuprophan, a regenerated cellulose membrane; and polyacrylonitrile. When microdialysis probes were tested in a stirred in vitro solution, large and statistically significant differences among the three membranes in extraction of acid metabolites (3,4‐dihydroxyphenylacetic acid, 5‐hydroxyindoleacetic acid, and homovanillic acid) and acetaminophen were found. Polyacrylonitrile had the highest extractions in vitro. In contrast, when microdialysis probes were implanted in vivo (in rat striatum), extraction of acid metabolites and acetaminophen did not differ significantly among the different membranes. These results are consistent with predictions made by a mathematical model of microdialysis and can be explained by the fact that in vitro the main factor limiting extraction is membrane resistance to diffusion, whereas tissue resistance to diffusion plays a more dominant role in vivo. These findings suggest that (aside from differences in surface area), the choice of semipermeable membrane will generally have little effect on in vivo microdialysis results. Furthermore, in vitro measurements of microdialysis probe extractions are not a reliable way of calibrating in vivo performance.

Quantitative Microdialysis: Analysis of Transients and Application to Pharmacokinetics in Brain

Abstract: The behavior of a microdialysis probe in vivo is mathematically described. A diffusion‐reaction model is developed that not only accounts for transport of substances through tissues and probe membranes but also accounts for transport across the microvasculature and metabolism. Time‐dependent equations are presented both for the effluent microdialysate concentration and for concentration profiles about the probe. The analysis applies either to measuring the tissue pharmacokinetics of drugs administered systemically, or for sampling of endogenously produced substances from tissue. In addition, an expression is developed for the transient concentration about the probe when it is used as an infusion device. All mathematical expressions are found to be a sum of an algebraic and an integral term. Theoretical prediction of time‐dependent probe behavior in brain has been compared with experimental data for acetaminophen administered at 15 mg/kg to rats by intravenous bolus. Plasma and whole striatal tissue samples were used to describe plasma kinetics and to estimate a capillary permeability‐area product of 0.07 min‐1. Theoretical prediction of transient effluent dialysate concentrations exhibited close agreement with experimental data over 60 min. Terminal decline of the dialysate effluent concentration was slightly overestimated but theoretical concentrations still lay within the 95% confidence interval of the experimental data at 112 min. Microvasculature transport and metabolism play major roles in determining microdialysate transient responses. Extraction fraction (recovery) has been shown to be a declining function in time for five probe operating conditions. High rates of metabolism and/or capillary transport affect the time required to approach steady‐state extraction, shortening the time as the rates increase. Conversely, for substances characterized by low permeabilities and negligible metabolism, experimental situations exist that are predicted to have very slow approaches to microdialysis steady state.

Results of Phase 3 of the CATIE Schizophrenia Trial

OBJECTIVE The Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) study examined the comparative effectiveness of antipsychotic treatments for individuals with chronic schizophrenia. Patients who had discontinued antipsychotic treatment in phases 1 and 2 were eligible for phase 3, in which they selected one of nine antipsychotic regimens with the help of their study doctor. We describe the characteristics of the patients who selected each treatment option and their outcomes. METHOD Two hundred and seventy patients entered phase 3. The open-label treatment options were monotherapy with oral aripiprazole, clozapine, olanzapine, perphenazine, quetiapine, risperidone, ziprasidone, long-acting injectable fluphenazine decanoate, or a combination of any two of these treatments. RESULTS Few patients selected fluphenazine decanoate (n=9) or perphenazine (n=4). Similar numbers selected each of the other options (range 33-41). Of the seven common choices, those who selected clozapine and combination antipsychotic treatment were the most symptomatic, and those who selected aripiprazole and ziprasidone had the highest body mass index. Symptoms improved for all groups, although the improvements were modest for the groups starting with relatively mild levels of symptoms. Side effect profiles of the medications varied considerably but medication discontinuations due to intolerability were rare (7% overall). CONCLUSIONS Patients and their doctors made treatment selections based on clinical factors, including severity of symptoms, response to prior treatments, and physical health status. Fluphenazine decanoate was rarely used among those with evidence of treatment non-adherence and clozapine was underutilized for those with poor previous response. Combination antipsychotic treatment warrants further study.

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.