Faculty Bibliography

OBJECTIVE: This study sought to examine the effect of ziprasidone on olanzapine or clozapine-associated medical morbidity such as insulin resistance, diabetes mellitus (DM) and impaired fasting glucose, obesity, and hyperlipidemia in patients with schizophrenia or schizoaffective disorder. METHOD: This was a 6-week, open label trial of ziprasidone 160 mg/day added to a stable dose of olanzapine or clozapine in 21 schizophrenia or schizoaffective patients with DM, impaired fasting glucose, or insulin resistance. RESULTS: Ten olanzapine-treated subjects and 11 clozapine-treated subjects were enrolled in the study. There were no significant differences between the two groups at baseline for age, gender, education, ethnicity, BMI, cholesterol levels, or fasting glucose. At week 6, there were no significant changes in weight, BMI, cholesterol levels, or fasting glucose. There was no significant difference in psychotic, negative, or depressive symptoms. QTc significantly increased at week 2 but not at week 6. CONCLUSIONS: The addition of 160 mg/day of ziprasidone was well tolerated but did not produce significant improvement in fasting glucose, insulin resistance, hyperlipidemia or lead to weight loss in olanzapine- or clozapine-treated subjects with schizophrenia or schizoaffective disorder

Olanzapine treatment has been associated with clinically meaningful weight increases, hypertriglyceridemia, insulin resistance, and diabetes mellitus. There are few options for olanzapine responders who fail other antipsychotic agents. Aripiprazole is a potent (high-affinity) partial agonist at D2 and 5-HT1A receptors and a potent antagonist at 5-HT2A receptor and is associated with less weight gain than olanzapine. We report the results of a 10-week placebo-controlled, double-blind crossover study that examined 15 mg/d aripiprazole's effects on weight, lipids, glucose metabolism, and psychopathology in overweight and obese schizophrenia and schizoaffective disorder subjects treated with a stable dose of olanzapine. During the 4 weeks of aripiprazole treatment, there were significant decreases in weight (P = 0.003) and body mass index (P = 0.004) compared with placebo. Total serum cholesterol (P = 0.208), high-density lipoprotein cholesterol (HDL-C; P = 0.99), HDL-2 (P = 0.08), HDL-3 (P = 0.495), and low-density lipoprotein cholesterol (P = 0.665) did not change significantly comparing aripiprazole treatment to placebo treatment. However, total serum triglycerides (P = 0.001), total very low-density lipoprotein cholesterol (VLDL-C; P = 0.01), and VLDL-1C and VLDL-2C (P = 0.012) decreased significantly during the aripiprazole treatment phase. The VLDL-3C tended lower during aripiprazole, but the decrease was not significant (P = 0.062). There was a decrease in C-reactive protein comparing aripiprazole treatment to placebo, although it did not reach significance (P = 0.087). The addition of aripiprazole to a stable dose of olanzapine was well tolerated and resulted in significant improvements on several outcome measures that predict risk for medical morbidity

BACKGROUND: Schizophrenia is associated with abnormalities in emotional processing and social cognition, which might result from disruption of the underlying neural mechanism(s) governing emotional learning and memory. To investigate this possibility, we measured the acquisition and extinction of conditioned fear responses and delayed recall of extinction in schizophrenia and control subjects. METHODS: Twenty-eight schizophrenia and 18 demographically matched control subjects underwent a 2-day fear conditioning, extinction learning, and extinction recall procedure, in which skin conductance response (SCR) magnitude was used as the index of conditioned responses. RESULTS: During fear acquisition, 83% of the control subjects and 57% of the patients showed autonomic responsivity ('responders'), and the patients showed larger SCRs to the stimulus that was not paired with the unconditioned stimulus (CS-) than the control subjects. Within the responder group, there was no difference between the patients and control subjects in levels of extinction learning; however, the schizophrenia patients showed significant impairment, relative to the control subjects, in context-dependent recall of the extinction memory. In addition, delusion severity in the patients correlated with baseline skin conductance levels. CONCLUSIONS: These data are consistent with prior evidence for a heightened neural response to innocuous stimuli in schizophrenia and elevated arousal levels in psychosis. The finding of deficient extinction recall in schizophrenia patients who showed intact extinction learning suggests that schizophrenia is associated with a disturbance in the neural processes supporting emotional memory

AIM: To help clinicians carry out a comprehensive, medical diagnostic assessment in first-episode patients who are suspected of developing schizophrenia. METHODS: Conceptual review of the published work with emphasis on the diagnostic goals of excluding medical causes of psychosis and establishing a medical baseline. RESULTS: There is no agreed-upon standard for the initial medical work-up of first-episode cases. Excluding secondary causes of schizophrenia requires consideration of likelihood of disease; laboratory test performance; and relevance of positive test results. CONCLUSIONS: We propose a medical work-up for first-episode psychosis that combines: (i) broad screening; (ii) exclusion of specific diseases informed by treatability and epidemiology; and (iii) medical baseline measures

BACKGROUND: Phosphodiesterase 5 (PDE5) inhibitors increase cyclic guanosine monophosphate (cGMP) concentrations in the intracellular pathway activated by N-methyl-D-aspartic acid receptors which is believed to mediate long-term potentiation and memory consolidation. The PDE5 inhibitor sildenafil has been shown to enhance memory in animal models. In addition, neuronal nitric oxide synthase, another component of the NMDA/nitric oxide/cGMP intracellular pathway, has been reported to be dysregulated in schizophrenia patients. MATERIALS AND METHODS: Seventeen adult schizophrenia outpatients treated with a stable dose of antipsychotic received a single oral dose of placebo, sildenafil 50 mg, and sildenafil 100 mg in random order with a 48-h interval between administrations. Psychiatric symptom ratings and a cognitive battery were performed at baseline and 1 hour following each administration of the study drug. In addition, memory consolidation was examined by testing recall 48 h later, prior to the next administration of the study drug. RESULTS: Fifteen subjects completed all three treatment conditions. One subject developed irritability and required hospitalization 2 days after receiving sildenafil 100 mg. Neither dose of sildenafil significantly affected cognitive performance or symptom ratings compared to the placebo. CONCLUSION: Despite evidence for cognitive-enhancing effects of sildenafil in animal models, the strategy for treating putative NMDA receptor-mediated memory deficits in schizophrenia with sildenafil 50 and 100 mg was not successful. It is possible that the doses used in this study were not optimal or that repeated dosing may be necessary to achieve therapeutic effects. Agents under development that inhibit other subtypes of PDE remain promising for schizophrenia and dementia

BACKGROUND: The application of weekly doses of D-cycloserine (DCS) to the enhancement of exposure-based treatments has been a particular achievement of translational research. It is not known, however, whether this enhancement effect can be extended to other forms of learning. In this study, we investigated the relative benefit of DCS versus placebo for enhancing nonemotional verbal and nonverbal memory across weekly trials. METHODS: We randomized healthy participants to weekly doses of 50 mg DCS or placebo, with 33 participants completing a 5-week protocol. Participants completed baseline neuropsychological evaluation and then 4 subsequent weeks of repeated learning tasks. RESULTS: No improvement was found in immediate or delayed memory following single doses of DCS for the memory tasks repeated on a weekly basis. Trends for an advantage of DCS were evident for novel word lists given each week. CONCLUSIONS: The learning tasks in our study were particularly distinct from the extinction learning paradigms that have shown strong DCS effects, and we were unable to demonstrate useful DCS effects with these nonemotional stimuli. Additional research is needed to elucidate the bounds of DCS augmentation effects on therapeutic learning