What is the overlap between subjective and objective cognitive impairments in MDD?

BACKGROUND: Cognitive impairments, such as memory deficits and executive impairment, are common among patients with major depressive disorder (MDD) and can be captured with objective or subjective assessments. The aim of this post-hoc analysis of the CONNECT study was to assess the degree of overlap between subjective and objective cognitive impairment among MDD patients, and to evaluate associated clinical characteristics. METHODS: The study was conducted from April 2012 to February 2014 and enrolled a total of 602 patients with MDD who reported subjective cognitive impairment. Efficacy was assessed using a battery of objective tests of cognitive function representing multiple domains: Digit Symbol Substitution Test performance, Trail Making Test A, Trail Making Test B, Congruent and Incongruent Stroop Test, Groton Maze Learning Test, Detection Task, Identification Task, and One-Back Task. The Cognitive and Physical Functioning Questionnaire (CPFQ) was used to capture patient-reported assessments of cognitive function. RESULTS: Although 48% of patients with MDD met our conservative criteria for subjectively defined marked cognitive impairment, 64% of patients with MDD met our conservative criteria for objectively defined cognitive impairment. Therefore, the proportion of patients defined as having impaired cognition was somewhat similar regardless of methodology. Overall, 80% of patients with MDD in this study reported either subjective or objective cognitive impairment per subjective and objective scales. However, the proportion of patients meeting criteria for both subjectively and objectively defined cognitive impairment was only 31%. This could be explained by the fact that the CPFQ total score was only modestly-although significantly-correlated with all but one of the objective tests. CONCLUSIONS: This post-hoc study shows that approximately 80% of patients with MDD participating in an antidepressant trial reported either subjective or objective cognitive impairment.

Location-based differences in cognition and functional capacity: Consistent levels of impairment in participants with schizophrenia compared to healthy controls.

Cognitive performance manifests regional differences, correlated with education. There is less information available about regional differences in performance-based measures of functional capacity. In multi-national trials focused on cognitive enhancement, it may be impossible to validate every measure in all locations. It is unknown if regional differences in healthy controls' (HC) performance affects relative levels of impairment in participants with schizophrenia (SCZ). A multi-site study comparing SCZ and HC administered the MATRICS Consensus Cognitive Battery (MCCB) and Virtual Reality Functional Capacity Assessment Tool (VRFCAT) to 164 HC participants and 164 with SCZ across three sites (Columbia, SC, Miami, and San Diego) and a representative sample of HC (n = 390) completed the VRFCAT in Durham, NC. Performance was compared between HC and SCZ participants at the validation sites. There were statistically significant cross-site differences in HC performance on both the MCCB and VRFCAT. Differences between HC and SCZ on MCCB and VRFCAT were substantial at all three sites, indicating that regional variations in HC performance did not induce reduced differences from SCZ participants. Regional differences were smaller than diagnostic group differences, suggesting that relative impairments of participants with SCZ is consistently preserved across performance differences in HC.

Relationships among neurocognition, symptoms and functioning in patients with schizophrenia: a path-analytic approach for associations at baseline and following 24 weeks of antipsychotic drug therapy.

BACKGROUND: Neurocognitive impairment and psychiatric symptoms have been associated with deficits in psychosocial and occupational functioning in patients with schizophrenia. This post-hoc analysis evaluates the relationships among cognition, psychopathology, and psychosocial functioning in patients with schizophrenia at baseline and following sustained treatment with antipsychotic drugs. METHODS: Data were obtained from a clinical trial assessing the cognitive effects of selected antipsychotic drugs in patients with schizophrenia. Patients were randomly assigned to 24 weeks of treatment with olanzapine (n = 159), risperidone (n = 158), or haloperidol (n = 97). Psychosocial functioning was assessed with the Heinrichs-Carpenter Quality of Life Scale [QLS], cognition with a standard battery of neurocognitive tests; and psychiatric symptoms with the Positive and Negative Syndrome Scale [PANSS]. A path-analytic approach was used to evaluate the effects of changes in cognitive functioning on subdomains of quality of life, and to determine whether such effects were direct or mediated via changes in psychiatric symptoms. RESULTS: At baseline, processing speed affected functioning mainly indirectly via negative symptoms. Positive symptoms also affected functioning at baseline although independent of cognition. At 24 weeks, changes in processing speed affected changes in functioning both directly and indirectly via PANSS negative subscale scores. Positive symptoms no longer contributed to the path-analytic models. Although a consistent relationship was observed between processing speed and the 3 functional domains, variation existed as to whether the paths were direct and/or indirect. Working memory and verbal memory did not significantly contribute to any of the path-analytic models studied. CONCLUSION: Processing speed demonstrated direct and indirect effects via negative symptoms on three domains of functioning as measured by the QLS at baseline and following 24 weeks of antipsychotic treatment.

Virtual reality assessment of functional capacity in people with Schizophrenia: Associations with reduced emotional experience and prediction of functional outcomes.

Virtual Reality (VR) approaches have had considerable success in measurement of functional capacity. However, it is not clear if factors other than cognitive impairment influence performance on VR measures. Many people with schizophrenia have significant negative symptoms and they could reduce engagement in assessment. 158 patients with schizophrenia performed the VRFCAT, were tested with the MCCB, were rated with the PANSS, and were rated on everyday functioning. Scores for reduced emotional experience and reduced expression were derived. Reduced emotional experience, but not reduced expression, was correlated with socially relevant VRFCAT subtasks and real-world social functioning. Performance on the socially relevant subtasks, but not the solitary subtasks, shared variance with work outcomes. MCCB performance was associated with both subdomains, but socially relevant subtasks shared more variance. Patients with higher reduced emotional experience validly engaged in socially relevant VR simulations, as indexed by correlations with outcome measures. These patients had poorer performance on socially relevant tasks than on solitary tasks. The differential validity of solitary vs. socially relevant simulations was supported by differences in correlates, suggesting that assessments with a focus on performance of simulated socially relevant tasks could be developed.

Effects of davunetide on N-acetylaspartate and choline in dorsolateral prefrontal cortex in patients with schizophrenia.

Schizophrenia is associated with extensive neurocognitive and behavioral impairments. Studies indicate that N-acetylaspartate (NAA), a marker of neuronal integrity, and choline, a marker of cell membrane turnover and white matter integrity, may be altered in schizophrenia. Davunetide is a neurotrophic peptide that can enhance cognitive function in animal models of neurodegeneration. Davunetide has recently demonstrated modest functional improvement in a study of people with schizophrenia. In a subset of these subjects, proton magnetic resonance spectroscopy ((1)H-MRS) was conducted to explore the effects of davunetide on change in NAA/creatine (NAA/Cr) and choline/creatine (choline/Cr) over 12 weeks of treatment. Of 63 outpatients with schizophrenia who received randomized davunetide (5 and 30 mg/day) or placebo in the parent clinical trial, 18 successfully completed (1)H-MRS in dorsolateral prefrontal cortex (DLPFC) at baseline and at 12 weeks. Cognition was assessed using the MATRICS Consensus Cognitive Battery (MCCB). NAA/Cr was unchanged for combined high- and low-dose davunetide groups (N=11). NAA/Cr in the high-dose davunetide group (N=8) suggested a trend increase of 8.0% (P=0.072) over placebo (N=7). Choline/Cr for combined high- and low-dose davunetide groups suggested a 6.4% increase (P=0.069), while the high-dose group showed a 7.9% increase (P=0.040) over placebo. Baseline NAA/Cr correlated with the composite MCCB score (R=0.52, P=0.033), as did individual cognitive domains of attention/vigilance, verbal learning, and social cognition; however, neither metabolite correlated with functional capacity. In this exploratory study, 12 weeks of adjunctive davunetide appeared to produce modest increases in NAA/Cr and choline/Cr in DLPFC in people with schizophrenia. This is consistent with a potential neuroprotective mechanism for davunetide. The data also support use of MRS as a useful biomarker of baseline cognitive function in schizophrenia. Future clinical and preclinical studies are needed to fully define the mechanism of action and cognitive effects of davunetide in schizophrenia.

Validation of a patient interview for assessing reasons for antipsychotic discontinuation and continuation.

INTRODUCTION: The Reasons for Antipsychotic Discontinuation Interview (RAD-I) was developed to assess patients' perceptions of reasons for discontinuing or continuing an antipsychotic. The current study examined reliability and validity of domain scores representing three factors contributing to these treatment decisions: treatment benefits, adverse events, and distal reasons other than direct effects of the medication. METHODS: Data were collected from patients with schizophrenia or schizoaffective disorder and their treating clinicians. For approximately 25% of patients, a second rater completed the RAD-I for assessment of inter-rater reliability. RESULTS: All patients (n = 121; 81 discontinuation, 40 continuation) reported at least one reason for discontinuation or continuation (mean = 2.8 reasons for discontinuation; 3.4 for continuation). Inter-rater reliability was supported (kappas = 0.63-1.0). Validity of the discontinuation domain scores was supported by associations with symptom measures (the Positive and Negative Syndrome Scale for Schizophrenia, the Clinical Global Impression - Schizophrenia Scale; r = 0.30 to 0.51; all P < 0.01), patients' primary reasons for discontinuation, and adverse events. However, the continuation domain scores were not significantly associated with these other indicators. DISCUSSION: Results support the reliability, convergent validity, and known-groups validity of the RAD-I for assessing patients' reasons for antipsychotic discontinuation. Further research is needed to examine validity of the RAD-I continuation section.

Validity and reliability of the Brazilian Portuguese version of the BACS (Brief Assessment of Cognition in Schizophrenia)

OBJECTIVE: To assess the validity and reliability of the Brazilian Portuguese version of the Brief Assessment of Cognition in Schizophrenia by examining its temporal stability, internal consistency, and discriminant and convergent validity. METHODS: The Brief Assessment of Cognition in Schizophrenia was administered to 116 stable patients with schizophrenia and 58 matched control subjects. To assess concurrent validity, a subset of patients underwent a traditional neuropsychological assessment. RESULTS: The patients with schizophrenia performed significantly worse than the controls (p<0.001) on all subtests of the Brief Assessment of Cognition in Schizophrenia and on the total score, which attests to the discriminant validity of the test. The global score of the Brief Assessment of Cognition in Schizophrenia was significantly correlated with all of the subtests and with the global score for the standard battery. The Brief Assessment of Cognition in Schizophrenia also had good test-retest reliability (rho>0.8). The internal consistency of the Brief Assessment of Cognition in Schizophrenia was high (Cronbach's α  ϝ 0.874). CONCLUSION: The Brazilian Portuguese version of the Brief Assessment of Cognition in Schizophrenia exhibits good reliability and discriminant and concurrent validity and is a promising tool for easily assessing cognitive impairment in schizophrenia and for comparing the performance of Brazilian patients with that of patients from other countries. .

Second-generation antipsychotics: reviewing the cost-effectiveness component of the CATIE trial.

The cost-effectiveness component of the 18-month CATIE trial of schizophrenia pharmacotherapy (n = 1460) showed that the first-generation antipsychotic perphenazine was US$300-600 per month less expensive than each of four second-generation antipsychotics, and no less effective across multiple measures. We consider whether or not each of eight potential methodological limitations could weaken this conclusion: follow-up rates, study duration, sample characteristics, the choice of outcome measures, exclusion of patients with tardive dyskinesia from assignment to perphenazine, choice of study drugs and doses, reliance on intention-to-treat analysis, and differences in prestudy treatment. We conclude that results of CATIE are robust to these limitations. Perphenazine seems to have been a more representative choice for first-generation antipsychotic comparison treatment than haloperidol.