The characteristics of cognitive neuroscience tests in a schizophrenia cognition clinical trial: Psychometric properties and correlations with standard measures.

In comparison to batteries of standard neuropsychological tests, cognitive neuroscience tests may offer a more specific assessment of discrete neurobiological processes that may be aberrant in schizophrenia. However, more information regarding psychometric properties and correlations with standard neuropsychological tests and functional measures is warranted to establish their validity as treatment outcome measures. The N-back and AX-Continuous Performance Task (AX-CPT) are two promising cognitive neuroscience tests designed to measure specific components of working memory and contextual processing respectively. In the current study, we report the psychometric properties of multiple outcome measures from these two tests as well as their correlations with standard neuropsychological measures and functional capacity measures. The results suggest that while the AX-CPT and N-back display favorable psychometric properties, they do not exhibit greater sensitivity or specificity with functional measures than standard neurocognitive tests.

A Phase II study of a histamine H3 receptor antagonist GSK239512 for cognitive impairment in stable schizophrenia subjects on antipsychotic therapy.

This Phase II exploratory study assessed GSK239512, a brain penetrant histamine H3 receptor antagonist, versus placebo on cognitive impairment in 50 stable outpatients with schizophrenia. Subjects were randomized to placebo or GSK239512 for 7 weeks (4 weeks titration). GSK239512 was associated with a small positive effect size (ES) on the CogState Schizophrenia Battery (CSSB) Composite Score (ES=0.29, CI=-0.40, 0.99) relative to placebo (primary endpoint). GSK239512's ES on CSSB domains were generally positive or neutral except Processing Speed, which favored placebo (ES=-0.46). Effects on the MATRICS Consensus Cognitive Battery were mostly neutral or favored placebo. GSK239512 was generally well tolerated with an adverse event profile consistent with the known class pharmacology. There was no evidence of overall beneficial effects of GSK239512 for CIAS in this population.

Bupropion sustained release added to group support for smoking cessation in schizophrenia: a new randomized trial and a meta-analysis.

OBJECTIVE: To clarify the efficacy and tolerability of bupropion sustained release (SR) for the treatment of cigarette smoking in people with schizophrenia. METHOD: The first study is a double-blind, placebo-controlled clinical trial with 32 outpatients from the Maryland Psychiatric Research Center. From May 2003 to July 2007, clinically stable people with a DSM-IV diagnosis of schizophrenia or schizoaffective disorder who smoked at least 10 cigarettes per day and who were interested in quitting smoking or cutting down were recruited for participation. All participated in a 9-week support group and were randomly assigned to receive 12 weeks of bupropion SR or placebo. The primary outcome measure was 4 weeks' sustained abstinence over the last 4 study weeks. Secondary outcome measures included decrease in smoking behavior and change in symptoms, neuropsychological performance, and side effects. In the second study, we performed an electronic literature search of MEDLINE in September 2008. Articles in English published between 2003 and 2008 were searched for the terms schizophrenia, bupropion SR, and smoking. Bibliographies of studies identified through the MEDLINE search were also examined. Case reports, open-label studies, crossover studies, and studies using nonstandard dosing of bupropion SR were excluded. In this way, 4 studies similar in methodology to the currently presented clinical trial were identified and the individual data combined in a meta-analysis. A random effects meta-analysis using Comprehensive Meta-Analysis software was used to obtain a pooled estimate of the odds ratio for 4-week smoking abstinence between bupropion SR and placebo. RESULTS: There were no significant results on the primary or secondary smoking measures for the clinical trial, although a numeric advantage favored the bupropion SR group. There were no significant findings for secondary symptom or side effect measures and no significant change in neuropsychological performance. For the meta-analysis totaling 226 subjects, there were significant findings in favor of bupropion SR. The pooled estimate of the odds ratio for 4-week abstinence was 2.7 (95% CI, 1.3 to 5.7; P = .009), and clinically significant greater smoking reduction in the bupropion SR group, with pooled difference estimates increasing over time between groups, became statistically significant by week 5 of study medication (P < .02). CONCLUSIONS: New clinical trial data and a meta-analysis strongly support the tolerability and efficacy of bupropion SR for the treatment of cigarette smoking in people with schizophrenia TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00176449.

Effect of the neuroprotective peptide davunetide (AL-108) on cognition and functional capacity in schizophrenia.

BACKGROUND: Cognitive dysfunction is a key predictor of functional disability in schizophrenia. Davunetide (AL-108, NAP) is an intranasally administered peptide currently being developed for treatment of Alzheimer's disease and related disorders. This study investigates effects of davunetide on cognition in schizophrenia. METHOD: Sixty-three subjects with schizophrenia received davunetide at one of two different doses (5, 30 mg) or placebo for 12 weeks in a multicenter, double-blind, parallel-group randomized clinical trial. The MATRICS Consensus Cognitive Battery (MCCB) assessed cognitive effects. The UCSD Performance-based Skills Assessment (UPSA) and the Schizophrenia Cognition Rating Scale (SCoRS) assessed functional capacity. Subjects continued their current antipsychotic treatment during the trial. RESULTS: There were no significant differences in MCCB change between davunetide and placebo over the three treatment arms (p=.45). Estimated effect-size (d) values were .34 and .21 favoring the 5 and 30 mg doses vs. placebo, respectively. For UPSA, there was a significant main effect of treatment across study arms (p=.048). Between-group effect size (d) values were.74 and .48, favoring the 5 and 30 mg doses, respectively. No significant effects were observed on the SCoRS or on symptom ratings. No significant side effects or adverse events were observed. CONCLUSION: Davunetide was well tolerated. Effects of davunetide on MCCB-rated cognition were not significant relative to placebo. In contrast, a significant beneficial effect was detected for the UPSA. Based upon effect-size considerations, sample sizes of at least 45-50 subjects/group would be required to obtain significant effects on both MCCB and UPSA, providing guidance for continued clinical development in schizophrenia.

Placebo-controlled trial of atomoxetine for weight reduction in people with schizophrenia treated with clozapine or olanzapine.

BACKGROUND: In recent years, several pharmacological and psychosocial interventions have examined ways to prevent or treat weight gain in people receiving second-generation antipsychotics. While there has been some success, in general, results have not been compelling. Atomoxetine is a selective norepinepherine reuptake inhibitor found to be associated with appetite suppression. Therefore, we examined whether atomoxetine may be of benefit for those who have gained weight on either clozapine or olanzapine. METHODS: The study was a double-blind, placebo-controlled trial. All participants received the same psychosocial platform: a structured support and exercise group. People with schizophrenia or schizoaffective disorder, on olanzapine or clozapine, who had gained at least 7% of their pre-clozapine or pre-olanzapine weight were eligible for a 24-week, randomized, parallel group, double-blind comparison of adjunctive atomoxetine or placebo. RESULTS: Thirty-seven participants (20 atomoxetine, 17 placebo) were randomized and 26 participants (14 atomoxetine, 12 placebo; 70.2%) completed the study. There were no significant group differences in baseline BMI (atomoxetine: 34.5±4.9; placebo: 35.7±7.0) or weight (atomoxetine: 102.2±15.7 kg; placebo: 104.3±17.5 kg). Both treatment groups showed modest, not significant, trends in weight loss, averaging about 2 kg. Gender or baseline antipsychotic treatment did not modify treatment effects on weight. Secondary outcomes included neuropsychological assessments, symptom assessments (BPRS, SANS) and safety assessments. Of these, only the group difference in Gordon distractibility test scores was statistically significant and favored treatment with atomoxetine. CONCLUSIONS: Atomoxetine is not effective for weight loss in this population, but both olanzapine and clozapine participants can lose weight with structured group support and exercise.

Exercise program adherence using a 5-kilometer (5K) event as an achievable goal in people with schizophrenia.

People with schizophrenia have a higher prevalence of obesity than the general population. Many people with this illness struggle with weight gain, due, in part, to medications and other factors that act as obstacles to exercise and healthy eating. Several studies have shown the benefits of behavioral weight loss programs targeting eating and/or exercise in people with schizophrenia. Fewer studies have used competitive events as a goal for an exercise program. The current study tested the feasibility of preparing, using an exercise program, for a 5-kilometer (5K) event in people with schizophrenia. The exercise program was a 10-week training program consisting of three supervised walking/jogging sessions per week and a weekly educational meeting on healthy behaviors. Almost 65% (11/17) of the subjects participated in all of the training sessions, and 82% (14/17) participated in the 5K event. Participants did not gain a significant amount of weight during the exercise program (median weight change = 0.7 kg; 25th percentile 0.5, 75th percentile 3.9, p = .10). This study suggests that using an achievable goal, such as a 5K event, promotes adherence to an exercise program and is feasible in a population of people with chronic schizophrenia.

Smoking history and motivation to quit in smokers with schizophrenia in a smoking cessation program.

OBJECTIVE: The present study sought to better understand the relationships among smoking history, motivation to change, and smoking cessation outcomes in people with schizophrenia who smoke. METHOD: We examined smoking and quit history, negative consequences due to smoking, readiness to change, smoking temptation, and confidence to quit in a sample of people diagnosed with schizophrenia or schizoaffective disorder according to DSM-IV criteria who were participating in a larger randomized trial of bupropion SR and a psychoeducational intervention for smoking cessation. Data were collected from June 2003 to May 2005. RESULTS: At baseline, participants reported high levels of nicotine dependence and daily smoking, as well as multiple recent and lifetime quit attempts that were generally brief in nature. Participants were most concerned about the health effects of smoking and endorsed reasons for smoking related to coping with negative affect and boredom. Most participants reported wanting to quit smoking, but the sample generally reported low levels of confidence in their ability to quit. During the course of participation in the intervention, self-efficacy to quit increased while temptation to smoke decreased; however readiness to quit remained unchanged. CONCLUSION: Smoking cessation programs for people with schizophrenia should focus on teaching coping skills for negative affect, boredom, and specific "high risk situations" for smoking in addition to education, medication, or nicotine replacement therapy. Further, cessation efforts may benefit from directly addressing low self-efficacy for quitting, rather than readiness for change alone, among people with schizophrenia.

A randomized clinical trial of MK-0777 for the treatment of cognitive impairments in people with schizophrenia.

BACKGROUND: In a previous pilot study, MK-0777--a γ-aminobutyric acid (GABA)(A) α2/α3 partial agonist--was reported to improve delayed memory and cognitive measures of prefrontal cortical function in people with schizophrenia. The current study was designed to further examine the efficacy and safety of MK-0777 for the treatment of cognitive impairments in schizophrenia. METHODS: Sixty people with DSM-IV schizophrenia entered a 4-week, multi-center, double-blind, placebo-controlled, randomized clinical trial. Participants were randomized to: MK-0777 3 mg b.i.d. (n = 18); MK-0777 8 mg b.i.d. (n = 21); or placebo (n = 21). Participants were clinically stable. The Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery, AX-Continuous Performance Test, and N-Back were used to assess cognition. The University of California San Diego (UCSD) Performance Based Skills Assessment-2 and the Schizophrenia Cognition Rating Scale assessed functional capacity and served as functional outcome coprimary measures. RESULTS: There were no significant group differences on the primary outcome measure, the MATRICS Consensus Cognitive Battery composite score. Secondary analyses suggested that participants randomized to placebo performed significantly better on visual memory and reasoning/problem-solving tests than participants assigned to either MK-0777 dose. There were no significant group differences on the AX-Continuous Performance Test or N-Back d prime scores or UCSD Performance-Based Skills Assessment-2 and Schizophrenia Cognition Rating Scale total scores. In general, MK-0777 was well-tolerated with minimal side effects. CONCLUSIONS: The study results suggest that MK-0777 has little benefit for cognitive impairments in people with schizophrenia. The GABA(A) receptor remains a promising target, but a more potent partial agonist with greater intrinsic activity at the GABA(A) α2 site might be needed for cognitive enhancement in schizophrenia.

Effects of the cannabinoid-1 receptor antagonist rimonabant on psychiatric symptoms in overweight people with schizophrenia: a randomized, double-blind, pilot study.

Weight gain is a major adverse effect of several second-generation antipsychotic medications. Rimonabant is a cannabinoid-1 receptor antagonist that promotes weight loss in the general population. We conducted a 16-week, double-blind, placebo-controlled study of rimonabant (20 mg/d) in people with schizophrenia or schizoaffective disorder, based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria, who were clinically stable on second-generation antipsychotics. Participants had a body mass index of 27 kg/m or higher with hyperlipidemia or body mass index of 30 kg/m or higher, and no current substance abuse/dependence (except nicotine), more than weekly cannabis use, or recent depressive symptoms/suicidality. An exercise and dietary counseling group was offered weekly. Target enrollment was 60; the trial was terminated early because of withdrawal of rimonabant from the European market. Fifteen participants were randomized (7 rimonabant, 8 placebo); 5 completed in each group. Rimonabant was associated with a greater reduction in Brief Psychiatric Rating Scale total score versus placebo (mean ± SE difference, -1.9 ± 0.8, P = 0.02), driven by differences in the Brief Psychiatric Rating Scale anxiety/depression (-1.4 ± 0.35, P = 0.0004) and hostility (-0.7 ± 0.3, P = 0.02) factors. Group differences were not significant for the Calgary Depression Scale total score (P = 0.24), Scale for the Assessment of Negative Symptoms total score (P = 0.13), weight, blood pressure, or fasting lipids or glucose. Rimonabant was well tolerated with no significant adverse events. No significant weight loss, metabolic effects, or adverse psychiatric effects were associated with the cannabinoid-1 receptor antagonist rimonabant in this small sample of people with schizophrenia. The endocannabinoid system remains a promising target for pharmacotherapy of schizophrenia and obesity.

Adjunctive risperidone for partially responsive people with schizophrenia treated with clozapine.

The large numbers of partial clozapine responders represent a major therapeutic challenge. Unfortunately, there are no clear data to support how best to treat these patients. This study examines the efficacy and safety of adjunctive risperidone in a well-defined treatment-resistant population optimally treated with clozapine. A total of 69 inpatients and outpatients with DSM-IV schizophrenia or schizoaffective disorder entered a 16-week double-blind, placebo-controlled, randomized clinical trial. Of them, 33 participants were randomized to risperidone and 36 were randomized to placebo. There was no significant group difference in the predefined response criteria. There were modest group differences for Brief Psychiatric Rating Scale (BPRS) positive symptoms, which were significant in the completer analysis (F=5.70; df=1, 70.3; p=0.02; ES=0.27) but not the intent-to-treat (ITT) analyses (F=3.01; df=1, 77.5; p=0.09; ES=0.19). A similar pattern was found for the BPRS total score, with the completer analysis showing a significant improvement in the risperidone group (F=5.21; df=1, 64.9; p=0.03; ES=0.27), whereas the ITT analysis was not significant (F=3.52; df=1, 71.3; p=0.06; ES=0.22). In addition, there was a small, but significant, group difference for negative symptoms, as measured by the SANS total score, which favored the risperidone group (F=5.67; df=1, 78.7; p=0.02; ES=0.24). There were no significant group differences on safety measures, including neuropsychological test and extrapyramidal symptom scores. A significant elevation of prolactin in the risperidone group was observed. The study results suggest that adjunctive risperidone may have a modest benefit for treatment-resistant clozapine patients. The study results are discussed in the context of previous double-blind studies of adjunctive risperidone. (clinicaltrials.gov, trial number: NCT00056498).

A randomized double-blind trial of atomoxetine for cognitive impairments in 32 people with schizophrenia.

BACKGROUND: Currently available antipsychotic medications offer only modest, if any, effects on cognitive performance in people with schizophrenia. Treatments that would improve these impairments could lead to better functional outcomes. Atomoxetine is a nonstimulant, selective norepinephrine reuptake inhibitor approved for the treatment of attention-deficit/hyperactivity disorder. In animals, it has been shown to increase extracellular levels of acetylcholine and dopamine in cortical and hippocampal regions. METHOD: Following a 2-week stabilization period, 32 subjects with DSM-IV-diagnosed schizophrenia or schizoaffective disorder were randomly assigned to atomoxetine (80 mg daily) or placebo for 8 weeks. All subjects were treated with antipsychotic monotherapy (excluding clozapine, aripiprazole, and first-generation antipsychotics). Neuropsychological test performance was the primary outcome variable, and the neuropsychological test battery included measures of attention, motor speed, executive function, processing speed, verbal and visual memory, and working memory (rated at baseline and end point). Symptom and side-effect ratings were performed every 2 weeks. The study was conducted from April 2004 through December 2006. RESULTS: There were no treatment group differences on the primary study outcome measure (overall mean z-score: Wilcoxon chi(2) = 0.21, df = 1, p = .64); nor was there significant evidence of variation in treatment effects on z-score changes across the individual neuropsychological tests (chi(2) = 8.22, df = 8, p = .41). No between-group differences were noted in symptom changes. Atomoxetine was well tolerated and was associated with a trend for improvement in extrapyramidal side effects relative to placebo (p = .063). CONCLUSION: Our results provide further evidence that atomoxetine has limited benefit for improving cognition in people with schizophrenia. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00161031.

The effects of galantamine on psychopathology in chronic stable schizophrenia.

OBJECTIVES: Galantamine is an acetylcholinesterase inhibitor and an allosteric modulator of the alpha4beta2 and alpha7 nicotinic receptors. There are several case reports describing the potential benefits of galantamine for negative symptoms associated with schizophrenia. This secondary analysis describes the effects of galantamine on psychopathology in people with schizophrenia. METHODS: Subjects with clinically stable chronic schizophrenia were randomized to adjunctive galantamine (24 mg/d) or placebo in a 12-week double-blind trial. Symptomatology was assessed with the Brief Psychiatric Rating Scale (BPRS) and the Clinical Global Impression Scale. The Scale for the Assessment of Negative Symptoms (SANS) was used to measure negative symptoms. RESULTS: Eighty-six patients with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition diagnosis of schizophrenia or schizoaffective disorder taking a stable dose of antipsychotic medications were randomized to adjunctive treatment with study drug (galantamine, n = 42; placebo, n = 44); 73 subjects completed the study (galantamine, n = 35; placebo, n = 38). No significant differences were found on BPRS total score (P = 0.585) or BPRS subfactor scores. Scale for the Assessment of Negative Symptoms total scores also did not decrease significantly (P = 0.106) in either group; however, galantamine treatment was associated with a greater benefit in the SANS subfactor, alogia (P = 0.007). CONCLUSIONS: The lack of robust significant effects of galantamine on negative, and other symptom domains, may be due to the relatively low baseline level of these symptoms in the tested population. Galantamine may have some benefit on certain negative symptoms, particularly alogia. Studies specifically designed to address the issue of the efficacy of galantamine for negative symptoms are needed to confirm this observation.

Initial phase 2 trial of a nicotinic agonist in schizophrenia.

OBJECTIVE: Nicotinic acetylcholine receptors are possible therapeutic targets for schizophrenia, as shown by neurobiological and molecular evidence for deficiencies in expression of alpha(7)-nicotinic receptors. Patients' heavy smoking suggests attempted self-medication through this mechanism. The agent 3-(2,4-dimethoxybenzylidene) anabaseine (DMXB-A) is a partial alpha(7)-nicotinic agonist and can be taken orally. A phase 1 trial showed evidence for cognitive enhancement in schizophrenia. METHOD: Thirty-one subjects with schizophrenia received DMXB-A at two different doses and placebo for periods of 4 weeks in a three-arm, two-site, double-blind, crossover phase 2 trial. The MATRICS Consensus Cognitive Battery assessed cognitive effects, and the Scale for the Assessment of Negative Symptoms (SANS) and Brief Psychiatric Rating Scale (BPRS) assessed clinical effects. Subjects continued their current antipsychotic drug during the trial and were nonsmokers. RESULTS: There were no significant differences in the MATRICS cognitive measures between DMXB-A and placebo over the three treatment arms, but the patients experienced significant improvement at the higher DMXB-A dose on the SANS total score and nearly significant improvement on the BPRS total score. Improvement was most notable on the SANS anhedonia and alogia subscales. Examination of the first treatment arm showed effects of DMXB-A on the attention/vigilance and working memory MATRICS domains, compared to baseline. Five subjects developed mild tremor, and nearly half had mild nausea while taking DMXB-A. CONCLUSION: DMXB-A, a nicotinic agonist that activates alpha(7)-nicotinic receptors, improved clinical ratings of negative symptoms that are generally resistant to treatment with dopamine antagonist antipsychotic drugs. The clinical utility of this treatment is not yet determined.

Galantamine for the treatment of cognitive impairments in people with schizophrenia.

OBJECTIVE: People with schizophrenia are characterized by a broad range of cognitive impairments. Despite appropriate treatment with conventional or second-generation antipsychotics, they continue to exhibit pronounced impairments. The current study was designed to examine the efficacy and safety of galantamine, an acetylcholinesterase inhibitor that also acts as an allosteric modulator at the alpha(4)beta(2) and alpha(7) nicotinic receptors, for the treatment of these impairments. METHOD: Eighty-six people with schizophrenia were entered into a 12-week double-blind, placebo-controlled, randomized clinical trial. Forty-two subjects were assigned to galantamine and 44 were assigned to placebo. The efficacy of galantamine for cognitive impairments was evaluated with neuropsychological measures of attention, motor speed, processing speed, verbal and visual memory, and working memory. RESULTS: The treatment effect for the overall composite score was not significant, but the heterogeneity of treatment effect analysis was significant. Follow-up analyses revealed that the subjects taking galantamine exhibited significant improvements on the WAIS-III digit symbol and verbal memory measures. In contrast, the subjects taking placebo showed a significant improvement on the GDS distractibility test. The group differences on the WAIS-III digit symbol and GDS distractibility test remained significant after correction for multiple comparisons. There were no significant between-group differences in motor speed or working memory. In general, safety analyses revealed that galantamine was well tolerated. CONCLUSIONS: Study results suggest that galantamine may have selective benefits for aspects of processing speed and verbal memory but interferes with practice effects during the performance of an attention task.

Olanzapine treatment of residual positive and negative symptoms.

OBJECTIVE: Olanzapine has been hypothesized to have superior efficacy in patients with treatment-resistant schizophrenia. The authors examined the comparative efficacy and safety of olanzapine and haloperidol in outpatients with partially responsive schizophrenia. METHOD: Sixty-three outpatients with schizophrenia who met retrospective and prospective criteria for either residual positive or residual negative symptoms entered a 16-week double-blind, parallel-groups comparison of olanzapine and haloperidol. RESULTS: There were no significant differences between the two drugs in their effect on positive or negative symptoms. There were no significant differences between the two treatment groups on measures of social and functional outcome. Olanzapine-treated patients had a significant reduction in extrapyramidal symptoms and subjective measures of stiffness and dry mouth, but the increases in systolic blood pressure and weight in olanzapine-treated patients were significantly greater than they were in haloperidol-treated patients. CONCLUSIONS: Olanzapine has limited differential benefit for either positive or negative symptoms in patients with treatment-resistant schizophrenia. Although olanzapine is associated with fewer extrapyramidal symptoms, other side effects may offset this benefit.