Lurasidone for the Treatment of Irritability Associated with Autistic Disorder.

The aim of this study was to evaluate the short-term efficacy and safety of lurasidone in treating irritability associated with autistic disorder. In this multicenter trial, outpatients age 6-17 years who met DSM-IV-TR criteria for autistic disorder, and who demonstrated irritability, agitation, and/or self-injurious behaviors were randomized to 6 weeks of double-blind treatment with lurasidone 20 mg/day (N = 50), 60 mg/day (N = 49), or placebo (N = 51). Efficacy measures included the Aberrant Behavior Checklist Irritability subscale (ABC-I, the primary endpoint) and the Clinical Global Impressions, Improvement (CGI-I) scale, and were analyzed using a likelihood-based mixed model for repeated measures. Least squares (LS) mean (standard error [SE]) improvement from baseline to Week 6 in the ABC-I was not significantly different for lurasidone 20 mg/day (-8.8 [1.5]) and lurasidone 60 mg/day (-9.4 [1.4]) versus placebo (-7.5 [1.5]; p = 0.55 and 0.36, respectively). CGI-I scores showed significantly greater LS mean [SE] improvement at Week 6 for lurasidone 20 mg/day versus placebo (2.8 [0.2] vs. 3.4 [0.2]; p = 0.035) but not for lurasidone 60 mg/day (3.1 [0.2]; p = 0.27). Discontinuation rates due to adverse events were: lurasidone 20 mg/day, 4.1%; 60 mg/day, 3.9%; and placebo, 8.2%. Adverse events with an incidence ≥10% (lurasidone combined, placebo) included vomiting (18.0, 4.1%) and somnolence (12.0, 4.1%). Modest changes were observed in weight and selected metabolic parameters. In this study, once-daily, fixed doses of 20 and 60 mg/day of lurasidone were not demonstrated to be efficacious compared to placebo for the short-term treatment of children and adolescents with moderate-to-severe irritability associated with autistic disorder.

Circumstances under which practice does not make perfect: a review of the practice effect literature in schizophrenia and its relevance to clinical treatment studies.

In this article, we review the literature on practice effects in schizophrenia, an underappreciated confound in interpreting cognitive improvement in clinical trials. We first examine claims regarding first- and second-generation antipsychotic medications as cognitive enhancers, and follow it with a discussion of recent studies demonstrating how practice or placebo effects may drive 'positive' findings. Thus, this review suggests that many previous findings can be reinterpreted in this light. Critically, we also make several suggestions about test construction, study design, and statistical analyses that the field might use to overcome this potential confound. Our suggestions may also have implications for drug discovery and regulatory approval of cognitive-enhancing adjunctive agents, in terms of study design and/or test psychometric characteristics, including the development of tests that are relatively insensitive to practice-related changes. Such advances might be important for improving the methodology involved in the assessment of cognitive change in treatment studies.

Cognitive improvement after treatment with second-generation antipsychotic medications in first-episode schizophrenia: is it a practice effect?

CONTEXT: Cognitive impairment in schizophrenia is frequent, involves multiple domains, and is enduring. Numerous recent clinical trials have suggested that second-generation antipsychotic medications significantly enhance cognition in schizophrenia. However, none of these studies included healthy controls undergoing repeated testing to assess the possibility that improvements might reflect simple practice effects. OBJECTIVE: To report the results on cognition of a randomized comparison of 2 widely prescribed second-generation antipsychotic medications, olanzapine and risperidone, in patients with first-episode schizophrenia and a healthy control group. DESIGN: Randomized clinical trial. SETTING: Hospital-based research units. Patients A total of 104 participants with first-episode schizophrenia and 84 healthy controls. MAIN OUTCOME MEASURES: Cognitive assessment of all study participants occurred at baseline, 6 weeks later, and 16 weeks later. Neurocognitive tests included measures of working memory and attention, speed, motor function, episodic memory, and executive function. RESULTS: No differential drug effects were observed. Of 16 cognitive measures, 9 demonstrated improvement over time and only 2 demonstrated greater rates of change than those observed in the healthy control group undergoing repeated assessment. The composite effect size for cognitive change was 0.33 in the healthy control group (attributed to practice) and 0.36 in the patients with first-episode schizophrenia. Improvements in cognition in the first-episode schizophrenia group could not be accounted for by medication dose, demographic variables, or intellectual level. CONCLUSIONS: The cognitive improvements observed in the trial were consistent in magnitude with practice effects observed in healthy controls, suggesting that some of the improvements in cognition in the first-episode schizophrenia group may have been due to practice effects (ie, exposure, familiarity, and/or procedural learning). Our results also indicated that differential medication effects on cognition were small. We believe that these findings have important implications for drug discovery and the design of registration trials that attempt to demonstrate cognitive enhancement.

Cognitive development in schizophrenia: follow-back from the first episode.

Despite consensus that schizophrenia is a neurodevelopmental disorder characterized by cognitive deficits, objective data documenting the course of cognitive development remain sparse. We conducted a follow-back study of patients ascertained at the time of their initial episode of schizophrenia or schizoaffective disorder, and a group of demographically matched healthy volunteers. We obtained school records containing standardized achievement test scores from the 1st through 12th grades, and scholastic aptitude test results from the 11th and 12th grades, and examined the developmental trajectories of cognitive performance with respect to prospective examinations conducted following participants' enrollment in our study. We found significant differences in academic achievement tests as early as the first grade, with scores from participants who would later develop schizophrenia lagging behind their peers by 0.8 to 1.1 grade equivalents. This gap widened resulting in a difference between groups of 1.5 to 1.8 grade equivalents by the 12th grade. In the subset of patients for whom SAT scores were available, we found that WAIS-R Full Scale IQ was 11.5 points lower than predicted from earlier SAT scores, suggesting a substantial decline in cognitive ability accompanying the initial episode of illness. These findings suggest that schizophrenia is marked by substantial cognitive deficits in the first grade, that there may be additional subtle decline preceding the overt onset of psychotic symptoms, and that the initial episode of illness is marked by additional decline. These observations may help advance concepts of premorbid cognitive ability in the schizophrenia syndrome and constrain models of pathophysiology.

Lack of normal association between cerebellar volume and neuropsychological functions in first-episode schizophrenia.

OBJECTIVE: Functional neuroimaging studies have identified a role for the cerebellum in the neuropsychology of schizophrenia. Few studies, however, have examined the relationship between cerebellar size and neuropsychological functioning in schizophrenia. The authors' goal was to examine this relationship in patients and healthy comparison subjects. METHOD: Total cerebellar volume was computed from magnetic resonance images in 48 male and 33 female patients experiencing a first episode of schizophrenia and in 14 male and nine female healthy comparison subjects. Patients and comparison subjects completed a comprehensive neuropsychological assessment encompassing six domains of functioning: executive, motor, language, visuospatial, memory, and attention. A global domain of functioning was computed as the mean of these six domains. RESULTS: Larger cerebellar volume correlated significantly with better global functioning in healthy subjects but not among patients with schizophrenia; this relationship was significantly stronger in healthy subjects than in patients. Additional analyses revealed significant associations between cerebellar volume and visuospatial, executive, and memory functions in healthy volunteers but not among patients. CONCLUSIONS: The cerebellum plays a role in higher cognitive functions in healthy individuals, and normal associations between cerebellar size and function are absent in patients experiencing a first episode of schizophrenia. These findings are consistent with neurobiological models implicating the cerebellum in the pathogenesis of schizophrenia.

Impairments in perceptual competency and maintenance on a visual delayed match-to-sample test in first-episode schizophrenia.

BACKGROUND: Deficits in working memory (WM) have been reported in patients with schizophrenia, but WM is a complex construct dependent on several subprocesses, including input representation (perceptual competency) and holding stimuli on-line (maintenance). A visual delayed match-to-sample task (DMST) was developed to isolate perceptual competency from maintenance during delays. It was hypothesized that patients in the first episode of schizophrenia would exhibit dissociable deficits in both WM domains. METHODS: Performance on the DMST was assessed in 57 patients in the first episode of schizophrenia or schizoaffective disorder and 22 healthy comparison subjects. In phase 1 of the DMST, a complex visual stimulus (target) was followed immediately by a forced choice between 2 test stimuli, and item difficulty (differences between the test stimuli) was titrated until each subject achieved a consistent accuracy (80%-90%) in this no-delay condition. In phase 2, a delay of 4 or 8 seconds with a mask of randomly illuminated pixels was introduced between target and test stimuli; test stimuli were fixed in difficulty level based on phase 1 titration. Main outcome measures were mean item difficulty attained in the no-delay condition and mean accuracy in matching after delay. RESULTS: Compared with controls, patients attained a lower level of difficulty in the no-delay condition (P =.001) and significantly lower accuracy with delay (P =.002). CONCLUSIONS: Deficits in both domains of WM suggest abnormality in the posterior and prefrontal cortexes. These deficits can be observed in a task involving complex visual pattern stimuli using only a brief delay and are present even in unmedicated patients in the first episode of illness.

Neurocognitive correlates of the COMT Val(158)Met polymorphism in chronic schizophrenia.

BACKGROUND: Neurocognitive deficits are recognized as a cardinal feature of schizophrenia, but the determinants of these deficits remain unknown. Recent reports have suggested that a functional polymorphism, Val(158)Met in exon III of the catechol-O-methyltransferase gene, shares approximately 4% variance with performance on the Wisconsin Card Sorting Test. These findings led to suggestions that the catechol-O-methyltransferase polymorphism may exert its effects by modulating prefrontal dopamine function, but few other neurocognitive measures have been examined, leaving open questions about phenotypic specificity. METHODS: We examined the effects of the catechol-O-methyltransferase Val(158)Met polymorphism in 58 individuals with chronic schizophrenia who completed a battery of 15 neurocognitive tests, which were reduced to four reliable neurocognitive domain scores. We examined the effects of genotype on these four domains and on global neurocognitive ability. RESULTS: The Met allele was associated with better performance in the Processing Speed and Attention domain, but not with other domain scores measuring executive and visuoperceptual functions, declarative verbal learning and memory, simple motor ability, or global neurocognitive function. Genotype shared approximately 11% of variance with Processing Speed and Attention scores, and approximately 2% of variance with Wisconsin Card Sorting Test scores. CONCLUSIONS: The findings provide independent support for the hypothesis that the catechol-O-methyltransferase Val(158)Met polymorphism influences neurocognitive function in schizophrenia, and suggest that the functional effects may be expressed on measures of Processing Speed and Attention. This information may prompt reconsideration of the "prefrontal dopamine" hypothesis and invites examination of a broader range of effects in efforts to refine the neurocognitive phenotype that is most relevant to variation in catechol-O-methyltransferase expression.

Neurocognitive effects of clozapine, olanzapine, risperidone, and haloperidol in patients with chronic schizophrenia or schizoaffective disorder.

OBJECTIVE: Newer antipsychotic drugs have shown promise in ameliorating neurocognitive deficits in patients with schizophrenia, but few studies have compared newer antipsychotic drugs with both clozapine and conventional agents, particularly in patients who have had suboptimal response to prior treatments. METHOD: The authors examined the effects of clozapine, olanzapine, risperidone, and haloperidol on 16 measures of neurocognitive functioning in a double-blind, 14-week trial involving 101 patients. A global score was computed along with scores in four neurocognitive domains: memory, attention, motor function, and general executive and perceptual organization. RESULTS: Global neurocognitive function improved with olanzapine and risperidone treatment, and these improvements were superior to those seen with haloperidol. Patients treated with olanzapine exhibited improvement in the general and attention domains but not more than that observed with other treatments. Patients treated with risperidone exhibited improvement in memory that was superior to that of both clozapine and haloperidol. Clozapine yielded improvement in motor function but not more than in other groups. Average effect sizes for change were in the small to medium range. More than half of the patients treated with olanzapine and risperidone experienced "clinically significant" improvement (changes in score of at least one-half standard deviation relative to baseline). These findings did not appear to be mediated by changes in symptoms, side effects, or blood levels of medications. CONCLUSIONS: Patients with a history of suboptimal response to conventional treatments may show cognitive benefits from newer antipsychotic drugs, and there may be differences between atypical antipsychotic drugs in their patterns of cognitive effects.

Neuropsychological correlates of hippocampal volumes in patients experiencing a first episode of schizophrenia.

OBJECTIVE: Despite evidence for hippocampal structural abnormalities in patients with schizophrenia, their functional correlates remain largely unknown. This study investigated the neuropsychological correlates of hippocampal volume in 43 men and 32 women experiencing a first episode of schizophrenia. METHOD: Posterior and anterior hippocampal volumes were computed from contiguous 3.1-mm magnetic resonance images and examined in relationship to six domains of neuropsychological functioning. Significant structure-function associations were investigated by examining the correlations between functioning and individual hippocampal slice volumes across the long axis of the hippocampus after interpolation to 10 equally spaced slice positions. RESULTS: Among men, worse executive and motor functioning correlated significantly with smaller anterior, but not posterior, hippocampal volume. The relationship between executive and motor functioning and hippocampal volume was not linear, however, when examined across the long axis of the hippocampus. Anterior hippocampal volume was more strongly correlated with both executive and motor functioning than with either memory or language functioning in men. None of the correlations between either posterior or anterior hippocampal volumes and the neuropsychological domains was significant among women. Anterior hippocampal volume was more strongly correlated with motor functioning in men than in women. CONCLUSIONS: Anterior hippocampal abnormalities associated with deficits on tests considered sensitive to frontal lobe functions implicate a defect in the integrated system linking frontal and mesiotemporal lobe regions. These findings further suggest that there are sex differences in structure-function relations in schizophrenia such that men may have more pronounced frontolimbic system abnormalities.

Spurious WAIS-R cholinergic profiles in schizophrenia.

The Fuld (1984) cholinergic profile based on the WAIS and WAIS-R age scaled scores has been shown to have moderate sensitivity and varying degrees of specificity in identifying dementia of the Alzheimer's type. The utility of this algorithm has increasingly been in doubt. The present study used young, well-diagnosed schizophrenic inpatients, a nondemented population with known cognitive deficits, to examine the specificity of the Fuld profile and its relationship to demographic and neuropsychological indices. The results found that the subjects who demonstrated a positive cholinergic profile (15%) did not differ neuropsychologically from the remaining sample. In the absence of other discriminating neuropsychological functions, the index is merely an artifact of relatively higher verbal abilities in the context of lower performance skills.

Interrater reliability in scoring the Wisconsin card sorting test.

Neuropsychological instruments continue to proliferate the field, while studies systematically addressing their accuracy and standardization have lagged behind. This paper examines the standard scoring criteria on a widely used neuropsychological test, the Wisconsin Card Sorting Test (WCST). Specifically, the scoring criteria for the perseveration variables are complex and interrater reliability had not yet been established. Study 1 revealed excellent interrater reliability between three individuals experienced with the WCST who had independently learned the scoring procedures. Study 2 demonstrated excellent interrater agreement among six novice raters. Some of the novice scorers used supplemental scoring instructions that were developed in an attempt to improve understanding of the manual. The supplemental scoring instructions reduced training time by 41% without affecting the high reliability between the raters. This paper also illustrates an appropriate use of generalizability theory, a powerful statistical method to examine reliability.