Pharmacological treatment of negative symptoms of schizophrenia: therapeutic opportunity or cul-de-sac?

Prevention and reversal of ketamine-induced schizophrenia related behavior by minocycline in mice: Possible involvement of antioxidant and nitrergic pathways

It has been hypothesized that oxidative imbalance and alterations in nitrergic signaling play a role in the neurobiology of schizophrenia. Preliminary evidence suggests that adjunctive minocycline treatment is efficacious for cognitive and negative symptoms of schizophrenia. This study investigated the effects of minocycline in the prevention and reversal of ketamine-induced schizophrenia-like behaviors in mice. In the reversal protocol, animals received ketamine (20 mg/kg per day intraperitoneally or saline for 14 days, and minocycline (25 or 50 mg/kg daily), risperidone or vehicle treatment from days 8 to 14. In the prevention protocol, mice were pretreated with minocycline, risperidone or vehicle prior to ketamine. Behaviors related to positive (locomotor activity and prepulse inhibition of startle), negative (social interaction) and cognitive (Y maze) symptoms of schizophrenia were also assessed. Glutathione (GSH), thiobarbituric acid-reactive substances (TBARS) and nitrite levels were measured in the prefrontal cortex, hippocampus and striatum. Minocycline and risperidone prevented and reversed ketamine-induced alterations in behavioral paradigms, oxidative markers (i.e. ketamine-induced decrease and increase in GSH levels and TBARS content, respectively) as well as nitrite levels in the striatum. These data provide a rationale for evaluating minocycline as a novel psychotropic agent and suggest that its mechanism of action includes antioxidant and nitrergic systems.

Adjunctive lisdexamfetamine dimesylate therapy in adult outpatients with predominant negative symptoms of schizophrenia: open-label and randomized-withdrawal phases

Negative symptoms of schizophrenia (NSS), related to hypodopaminergic activity in the mesocortical pathway and prefrontal cortex, are predictive of poor outcomes and have no effective treatment. Use of dopamine-enhancing drugs (eg, psychostimulants) has been limited by potential adverse effects. This multicenter study examined lisdexamfetamine dimesylate (LDX), a d-amphetamine prodrug, as adjunctive therapy to antipsychotics in adults with clinically stable schizophrenia and predominant NSS. Outpatients with stable schizophrenia, predominant NSS, limited positive symptoms, and maintained on stable atypical antipsychotic therapy underwent a 3-week screening, 10-week open-label adjunctive LDX (20-70 mg/day), and 4-week, double-blind, randomized, placebo-controlled withdrawal. Efficacy measures included a modified Scale for the Assessment of Negative Symptoms (SANS-18) and Positive and Negative Syndrome Scale (PANSS) total and subscale scores. Ninety-two participants received open-label LDX; 69 received double-blind therapy with placebo (n=35) or LDX (n=34). At week 10 (last observation carried forward; last open-label visit), mean (95% confidence interval) change in SANS-18 scores was -12.9 (-15.0, -10.8; P<0.0001). At week 10, 52.9% of participants demonstrated a minimum of 20% reduction from baseline in SANS-18 score. Open-label LDX was also associated with significant improvement in PANSS total and subscale scores. During the double-blind/randomized-withdrawal phase, no significant differences (change from randomization baseline) were found between placebo and LDX in SANS-18 or PANSS subscale scores. In adults with clinically stable schizophrenia, open-label LDX appeared to be associated with significant improvements in negative symptoms without positive symptom worsening. Abrupt LDX discontinuation was not associated with positive or negative symptom worsening. Confirmation with larger controlled trials is warranted.

Cognitive Behavioral Therapy for negative symptoms (CBT-n) in psychotic disorders: a pilot study

BACKGROUND AND OBJECTIVES

The treatment of negative symptoms in schizophrenia is a major challenge for mental health care. One randomized controlled trial found that cognitive therapy for low-functioning patients reduced avolition and improved functioning, using an average of 50.5 treatment sessions over the course of 18 months. The aim of our current pilot study was to evaluate whether 20 sessions of Cognitive Behavioral Therapy for negative symptoms (CBT-n) would reduce negative symptoms within 6 months. Also, we wanted to test the cognitive model of negative symptoms by analyzing whether a reduction in dysfunctional beliefs mediated the effects on negative symptoms.

METHOD

In an open trial 21 adult outpatients with a schizophrenia spectrum disorder with negative symptoms received an average of 17.5 sessions of CBT-n. At baseline and end-of-treatment, we assessed negative symptoms (PANSS) and dysfunctional beliefs about cognitive abilities, performance, emotional experience, and social exclusion. Bootstrap analysis tested mediation.

RESULTS

The dropout rate was 14% (three participants). Intention-to-treat analyses showed a within group effect size of 1.26 on negative symptoms (t = 6.16, | Sig = 0.000). Bootstrap analysis showed that dysfunctional beliefs partially mediated the change.

LIMITATIONS

The uncontrolled design induced efficacy biases. Also, the sample was relatively small, and there were no follow-up assessments.

CONCLUSIONS

CBT-n may be effective in reducing negative symptoms. Also, patients reported fewer dysfunctional beliefs about their cognitive abilities, performance, emotional experience, and social exclusion, and this reduction partially mediated the change in negative symptoms. The reductions were clinically important. However, larger and controlled trials are needed.

Intracellular pathways of antipsychotic combined therapies: implication for psychiatric disorders treatment

Dysfunctions in the interplay among multiple neurotransmitter systems have been implicated in the wide range of behavioral, emotional and cognitive symptoms displayed by major psychiatric disorders, such as schizophrenia, bipolar disorder or major depression. The complex clinical presentation of these pathologies often needs the use of multiple pharmacological treatments, in particular (1) when monotherapy provides insufficient improvement of the core symptoms; (2) when there are concurrent additional symptoms requiring more than one class of medication and (3) in order to improve tolerability, by using two compounds below their individual dose thresholds to limit side effects. To date, the choice of drug combinations is based on empirical paradigm guided by clinical response. Nonetheless, several preclinical studies have demonstrated that drugs commonly used to treat psychiatric disorders may impact common intracellular target molecules (e.g. Akt/GSK-3 pathway, MAP kinases pathway, postsynaptic density proteins). These findings support the hypothesis that convergence at crucial steps of transductional pathways could be responsible for synergistic effects obtained in clinical practice by the co-administration of those apparently heterogeneous pharmacological compounds. Here we review the most recent evidence on the molecular crossroads in antipsychotic combined therapies with antidepressants, mood stabilizers, and benzodiazepines, as well as with antipsychotics. We first discuss clinical clues and efficacy of such combinations. Then we focus on the pharmacodynamics and on the intracellular pathways underpinning the synergistic, or concurrent, effects of each therapeutic add-on strategy, as well as we also critically appraise how pharmacological research may provide new insights on the putative molecular mechanisms underlying major psychiatric disorders.

Has the prevalence, clinical presentation and social functioning of schizophrenia changed over the last 25 years? Nithsdale schizophrenia survey revisited

BACKGROUND

Major changes in the treatment of schizophrenia have taken place in recent years, including a shift from inpatient to community care, and the introduction of second-generation antipsychotics and psychosocial interventions. Recent evidence has questioned the superiority of these interventions over older treatments.

AIMS

We wished to ascertain the impact of changes in the treatment of schizophrenia in a geographically-defined area, focusing on clinical symptoms and psychosocial outcome.

METHODS

In 2006, we replicated the survey carried out in 1981, identifying the population of people with schizophrenia living in Nithsdale, South-West Scotland, measuring prevalence using the 'key informant' method. We assessed their clinical and social functioning, using similar scales, and compared measures across both time periods.

RESULTS

We identified 205 people with schizophrenia, a point prevalence of 3.59/1000 general population. In 2006, while fewer people experienced negative symptoms, a greater number experienced positive symptoms. There were no significant differences in the prevalence of tardive dyskinesia or Parkinsonism, though tremor was less common in the 2006 population. In 2006, there were fewer people living with a spouse/partner or parents, and fewer were in open employment in comparison to the 1981 population. The overall level of social adjustment had not changed.

CONCLUSIONS

The clinical manifestation of schizophrenia appears to have changed over the last 25 years, within this geographically-defined area, the prevalence of negative symptoms having decreased, and positive symptoms seem to have increased. The level of social functioning does not appear to have changed over the last 25 years.

Treatments in context: transcranial direct current brain stimulation as a potential treatment in pediatric psychosis

Childhood-onset schizophrenia is a chronic, severe form of schizophrenia, and is typically treatment resistant. Even after optimized pharmacotherapy, a majority (over 70%) of these pediatric patients present lasting psychotic symptoms and impaired cognition, necessitating the need for novel treatment modalities. Recent work in transcranial magnetic stimulation suggests moderate efficacy in symptom reduction in adult patients with schizophrenia; however, the transcranial magnetic stimulation treatment is cumbersome for this severely ill population. Transcranial direct current stimulation may provide a safe and effective adjuvant treatment for continued residual symptoms of schizophrenia.

Negative symptoms and executive function in schizophrenia: does their relationship change with illness duration?

BACKGROUND

Negative symptoms and cognitive dysfunction are of crucial functional and prognostic importance in schizophrenia. However, the nature of the relationship between them and the factors that may influence it have not been well established.

AIMS

To investigate whether the relationship between negative symptoms and executive function changes according to the duration of illness in schizophrenia.

METHODS

The Positive and Negative Syndrome Scale was used to assess psychopathology and the Wisconsin Card Sorting Test (WCST) to evaluate executive function in a sample of 200 schizophrenic patients who were classified in 3 groups according to their duration of illness: up to 5 years (short duration group), 6-20 years (intermediate duration group) and over 20 years of illness (long duration group).

RESULTS

Medium-sized correlations were found between negative symptoms and WCST performance as assessed by the number of completed categories in all 3 groups. However, differences were found according to the duration of schizophrenia. For patients in the short duration group, negative symptoms correlated with WCST nonperseverative errors, but for those in the long duration group the correlation was with perseverative errors.

CONCLUSION

We found a differential relationship between negative and cognitive symptoms in different stages of schizophrenia. Illness duration should be considered when studying the relationship between negative symptoms and cognition.

Duration of untreated psychosis and negative symptoms--a systematic review and meta-analysis of individual patient data

BACKGROUND

Longer duration of untreated psychosis (DUP) is associated with poorer outcome in terms of positive symptoms, relapse rate, and time to remission. In contrast, the association with negative symptoms is less consistent.

AIMS

The study had three aims. First, to arrive at a more precise estimate of the correlation between DUP and negative symptoms than previous reviews, by substantially increasing the amount of available data. Second, to see whether the strength of this correlation attenuated over longer follow-up intervals. Third, to determine whether there is a relationship between DUP and changes in negative symptoms.

METHOD

Relevant databases were searched for studies published between December 1992 and March 2009 that reported data on DUP and negative symptoms. We obtained individual patient data where possible and calculated summary correlations between DUP and negative symptoms for each study at baseline, short and long-term follow-up. We used multilevel regression analysis to examine whether the effect of DUP on negative symptoms was the greatest in the early stages of illness.

RESULTS

We included 28 non-overlapping studies from the 402 papers detected by the search strategy. After contacting the authors we obtained individual patient data from 16 of these studies involving 3339 participants. The mean DUP was 61.4 weeks (SD=132.7, median DUP=12.0). Shorter DUP was significantly associated with less severe negative symptoms at baseline and also at short (1-2 years) and longer term follow-up (5-8 years) (r=0.117, 0.180 and 0.202 respectively, p<0.001). The relationship between improvement in negative symptoms and DUP was found to be non-linear: people with a DUP shorter than 9 months showed substantially greater negative symptom reduction than those with a DUP of greater than 9 months.

CONCLUSIONS

Shorter DUP is associated with less severe negative symptoms at short and long-term follow up, especially when the DUP is less than 9 months. Since there is no effective treatment for negative symptoms, reducing DUP to less than 9 months may be the best way to ameliorate them.

Societal participation: examining the impact of a rehabilitation approach for young people with schizophrenia

This paper is based on research that focuses on the impact of a rehabilitation approach with respect to 99 young people diagnosed with schizophrenia in a Dutch mental health facility. The approach focused on societal participation goals. Nurses and social workers play a key role in such treatment. The research focused on developmental trajectories and showed significant improvement with respect to societal participation levels. Impairment scores remained stable. The results indicate that rehabilitation counselling by nurses and social workers, in addition to medication and psychosocial treatment and integrated in a multidisciplinary team, can make a difference in a patient's societal participation.

Yoga therapy for Schizophrenia

Schizophrenia is one of the most severe mental disorders. Despite significant advances in pharmacotherapy, treatment remains sub-optimal, with many patients having persisting deficits, especially in cognitive and social functioning. Yoga as a therapy has proven to be effective as a sole or additional intervention in psychiatric disorders such as depression and anxiety. Recently, there has been significant interest in the application of yoga therapy in psychosis and schizophrenia. To review a) the evidence for the use of yoga therapy in patients with schizophrenia b) studies which have been done in this area, c) the barriers for reaching yoga to patients, and d) future directions, an English language literature search of PubMed/MEDLINE, Google Scholar, and EBSCO as well as grey literature was done. Research reports have demonstrated the feasibility and efficacy of yoga as an add-on therapy in schizophrenia, particularly in improving negative symptomatology and social cognition. However, the biological underpinnings of this effect remain unclear, although there are some indications that hormones like oxytocin may contribute to the changes in social cognition.

Therapeutic efficacy of add-on yogasana intervention in stabilized outpatient schizophrenia: Randomized controlled comparison with exercise and waitlist

BACKGROUND

Schizophrenia is a highly disabling illness. Previous studies have shown yoga to be a feasible add-on therapy in schizophrenia.

AIMS

The current study aimed to test the efficacy of yoga as an add-on treatment in outpatients with schizophrenia.

SETTINGS AND DESIGN

The study done at a tertiary psychiatry center used a single blind randomized controlled design with active control and waitlist groups.

MATERIALS AND METHODS

Consenting patients with schizophrenia were randomized into yoga, exercise, or waitlist group. They continued to receive pharmacological therapy that was unchanged during the study. Patients in the yoga or exercise group were offered supervised daily procedures for one month. All patients were assessed by a blind rater at the start of the intervention and at the end of 4 months.

RESULTS

Kendall tau, a nonparametric statistical test, showed that significantly more patients in the yoga group improved in Positive and Negative Syndrome Scale (PANSS) negative and total PANSS scores as well as social functioning scores compared with the exercise and waitlist group. Odds ratio analysis showed that the likelihood of improvement in yoga group in terms of negative symptoms was about five times greater than either the exercise or waitlist groups.

CONCLUSION

In schizophrenia patients with several years of illness and on stabilized pharmacological therapy, one-month training followed by three months of home practices of yoga as an add-on treatment offered significant advantage over exercise or treatment as usual. Yoga holds promise as a complementary intervention in the management of schizophrenia.

Striatal D2 receptors regulate dendritic morphology of medium spiny neurons via Kir2 channels

Structural plasticity in the adult brain is essential for adaptive behaviors and is thought to contribute to a variety of neurological and psychiatric disorders. Medium spiny neurons of the striatum show a high degree of structural plasticity that is modulated by dopamine through unknown signaling mechanisms. Here, we demonstrate that overexpression of dopamine D2 receptors in medium spiny neurons increases their membrane excitability and decreases the complexity and length of their dendritic arbors. These changes can be reversed in the adult animal after restoring D2 receptors to wild-type levels, demonstrating a remarkable degree of structural plasticity in the adult striatum. Increased excitability and decreased dendritic arborization are associated with downregulation of inward rectifier potassium channels (Kir2.1/2.3). Downregulation of Kir2 function is critical for the neurophysiological and morphological changes in vivo because virally mediated expression of a dominant-negative Kir2 channel is sufficient to recapitulate the changes in D2 transgenic mice. These findings may have important implications for the understanding of basal ganglia disorders, and more specifically schizophrenia, in which excessive activation of striatal D2 receptors has long been hypothesized to be of pathophysiologic significance.

A placebo-controlled study of the modafinil added to risperidone in chronic schizophrenia

RATIONAL

In recent years, evidence suggests that modafinil may be useful for certain symptom domains of schizophrenia, especially for the negative and cognitive symptoms. However, the results are not consistent.

OBJECTIVE

This study was designed to investigate the effect of modafinil added to risperidone in patients with chronic schizophrenia in a double blind and randomized clinical trial.

METHODS

Participants were inpatients males (35) and females (11), ages 20-49 years at two teaching psychiatric hospital in Iran. All patients were in the active phase of the illness and met DSM-IV-TR criteria for schizophrenia. Patients were allocated in a random fashion 23 patients to risperidone 6 mg/day plus modafinil 200 mg/day and 23 patients to risperidone 6 mg/day plus placebo. The principal measure of outcome was the positive and negative syndrome scale (PANSS). Patients were assessed by a psychiatrist at baseline and after 2, 4, 6 and 8 weeks after the start of medication.

RESULTS

The modafinil group had significantly greater improvement in the negative symptoms as well as PANSS total scores over the 8-week trial. Therapy with 200 mg/day of modafinil was well tolerated and no clinically important side effects were observed.

CONCLUSION

The present study indicates modafinil as a potential adjunctive treatment strategy for treatment of schizophrenia particularly the negative symptoms. Nevertheless, results of larger-controlled trials are needed before recommendation for broad clinical application can be made.

Adjunct treatments for schizophrenia and bipolar disorder: what to try when you are out of ideas

The pharmacologic treatment of schizophrenia and bipolar disorder leaves much to be desired. Repurposed drugs, which are approved for other medical conditions, represent an underutilized therapeutic resource for patients who have not responded to other drugs. Using experience gained from a decade of repurposed drug studies by the Stanley Medical Research Institute and search of the literature, we have identified nine such drugs for which there is some evidence of efficacy for schizophrenia and/or bipolar disorder. These include: aspirin; celecoxib; estrogen/raloxifene; folate; minocycline; mirtazapine; omega-3 fatty acids; pramipexole; and, pregnenolone. The evidence of efficacy is reviewed for each drug. Because there is little or no financial incentive for pharmaceutical companies to promote such drugs, there is a paucity of definitive trials, and these drugs are less widely known than they deserve to be. Biomarker studies should also be carried out to identify subgroups of patients who do respond to these drugs.

Schizophrenia as a disorder of too little dopamine: implications for symptoms and treatment

Antipsychotics represent the first effective therapy for schizophrenia, with their benefits linked to dopamine D2 blockade. Schizophrenia was soon identified as a hyperdopaminergic disorder, and antipsychotics proved to be reasonably effective in controlling positive symptoms. However, over the years, schizophrenia has been reconceptualized more broadly, now defined as a heterogeneous disorder with multiple symptom domains. Negative and cognitive features, not particularly responsive to antipsychotic therapy, have taken on increased importance--current thinking suggests that these domains predate the onset of positive symptoms and are more closely tied to functional outcome. That they are better understood in the context of decreased dopamine activity suggests that schizophrenia may fundamentally represent a hypodopaminergic disorder. This shift in thinking has important theoretical implications from the standpoint of etiology and pathophysiology, but also clinically in terms of treatment and drug development.

A double-blind, placebo-controlled study of traditional Chinese medicine sarsasapogenin added to risperidone in patients with negative symptoms dominated schizophrenia

OBJECTIVE To identify whether sarsasapogenin, a sapogenin from the Chinese medicinal herb Anemarrhena Asphodeloides Bunge, would augment the efficacy of risperidone and significantly improve cognitive functions in patients with negative symptoms dominated schizophrenia. METHODS The trial was a double-blind, placebo-controlled, parallel-group design. The eligible patients were randomized into 2 treatment groups: sarsasapogenin group (sarsasapogenin plus risperidone for 8 weeks, n = 41) and placebo group (risperidone only for 8 weeks, n = 39). At the baseline, as well as at weeks 2, 4 and 8 of treatment, the therapeutic response was measured by using scales including Positive and Negative Symptoms Scale (PANSS), Wechsler Memory Scale (WMS), modified Chinese Wechsler Adult Intelligence Scale (mWAIS), Clinical Global Impression (CGI) and Brief Psychiatry Rating Scale (BPRS). The study period for each subject was 8 weeks and duration of overall trial was 2 years. RESULTS Patients treated with sarsasapogenin plus risperidone demonstrated no statistically significant differences in changes in PANSS, WMS or mWAIS score at the end-point of the trial compared with patients treated with placebo plus risperidone. The incidence of treatment-emergent adverse events in patients treated with sarsasapogenin was not different from that observed in placebo group. CONCLUSION Sarsasapogenin did not augment the efficacy of risperidone in treating negative symptoms dominated schizophrenia. Sarsasapogenin at a dosage of 200 mg per day added to a flexible dosage of risperidone at 2-4 mg per day is safe and well tolerated by patients with negative symptoms dominated schizophrenia.

Negative expectancy appraisals and defeatist performance beliefs and negative symptoms of schizophrenia

Negative symptoms have clear functional implications in schizophrenia and are typically unresponsive to current treatments. The cognitive model of negative symptoms suggests that dysfunctional beliefs are influential in the development and maintenance of negative symptoms and schizophrenia. The current study reports on a preliminary investigation of a new measure of Negative Expectancy Appraisals (specifically beliefs about limited probability of success and perception of limited cognitive resources), and also evaluates whether dysfunctional beliefs are more closely linked to particular subdomains of negative symptoms. Sixty two individuals with schizophrenia completed measures of dysfunctional beliefs and were rated on negative symptoms. Analyses indicated that the endorsement of beliefs regarding low expectations for success and perception of limited resources (Negative Expectancy Appraisals) are robustly associated with diminished experience negative symptoms (avolition, asociality, and anhedonia), but are not associated with negative symptoms reflecting diminished expressivity (blunted affect, alogia). Similarly, Defeatist Performance Beliefs are modestly related to diminished experience, but not diminished expression, negative symptoms. Negative Expectancy Appraisals were also robustly linked to depressive symptoms. Results from the current study provide evidence that dysfunctional beliefs are clearly relevant to consider in relation to negative symptoms, and may represent a fruitful treatment target.

Symptom and functional outcomes for a 5 year early intervention program for psychoses

There continues to be controversy concerning the long term benefits of specialized early intervention programs (SEI) for psychotic disorders. Recent reports of five year outcomes for SEI programs indicate that benefits of early intervention programs at two year follow-up have disappeared at five years. The Prevention and Early Intervention Program for Psychoses (PEPP) in London, Ontario offers continuity of care for five years, with a lower intensity level of specialized intervention after the initial two years. In this paper we examine whether the outcomes observed at two years were maintained at five year follow-up. In addition, it was possible to compare PEPP outcomes with those of the OPUS project at two and five years. Results indicate that improvement of symptoms between entry into PEPP and two year follow-up were maintained at five years. In addition, there was further improvement in global functioning between two and five year follow-up. Comparison of PEPP outcomes at two and five year follow-up to those of OPUS suggest that longer term continuity of care within SEI is associated with continuing benefits at least with respect to level of positive symptoms and functioning.

Prefrontal lobe dysfunction predicts treatment response in medication-naive first-episode schizophrenia

Dysfunction of the frontal lobe is considered to be central to the pathology of schizophrenia. However, the nature of these abnormalities is unclear, in particular whether they are affected by treatment. In an earlier functional MRI study of our group we found dorsolateral prefrontal lobe (DLPFC) dysfunction to be present in medication-naive first-episode patients. In this follow-up study, we investigated whether treatment with atypical antipsychotics had an effect on DLPFC functioning, and whether (change in) DLPFC functioning was related to treatment response. Twenty-three medication-naive, first-episode male schizophrenia patients and 33 matched healthy controls were scanned at baseline and were re-scanned after 10 weeks, while performing a modified Sternberg working-memory task. We specifically investigated the effect of practice on brain activation, defined as the signal change between a novel and practiced working-memory task. After the baseline scan, patients were treated with atypical antipsychotics. Based on their symptom change after ten weeks, patients were divided into responders and non-responders We found DLPFC function did not change after 10 weeks in healthy controls or in patients who received treatment. However, while patients who responded to treatment did not differ from controls, non-responders showed a reduced practice effect in the DLPFC that was present already at baseline, which did not change after treatment. A reduced practice effect in the DLFPC at baseline was found to be predictive of poor treatment response at 10 weeks. These results suggest that prefrontal lobe dysfunction reflects a distinct neuropathological substrate in a subgroup of treatment non-responsive schizophrenia patients.

Evidence-based guidelines for the pharmacological treatment of schizophrenia: recommendations from the British Association for Psychopharmacology

These guidelines from the British Association for Psychopharmacology address the scope and targets of pharmacological treatment for schizophrenia. A consensus meeting, involving experts in schizophrenia and its treatment, reviewed key areas and considered the strength of evidence and clinical implications. The guidelines were drawn up after extensive feedback from the participants and interested parties, and cover the pharmacological management and treatment of schizophrenia across the various stages of the illness, including first-episode, relapse prevention, and illness that has proved refractory to standard treatment. The practice recommendations presented are based on the available evidence to date, and seek to clarify which interventions are of proven benefit. It is hoped that the recommendations will help to inform clinical decision making for practitioners, and perhaps also serve as a source of information for patients and carers. They are accompanied by a more detailed qualitative review of the available evidence. The strength of supporting evidence for each recommendation is rated.

Impact of species variability and 'probe-dependence' on the detection and in vivo validation of allosteric modulation at the M4 muscarinic acetylcholine receptor

BACKGROUND AND PURPOSE

We recently characterized LY2033298 as a novel allosteric modulator and agonist at M(4) muscarinic acetylcholine receptors (mAChRs). Evidence also suggested a difference in the potency of LY2033298 at rodent relative to human M(4) mAChRs. The current study investigated the basis for the species difference of this modulator and used this knowledge to rationalize its in vivo actions.

EXPERIMENTAL APPROACH

LY2033298 was investigated in vitro in CHO cells stably expressing human or mouse M(4) mAChRs, using assays of agonist-induced ERK1/2 or GSK-3α phosphorylation, [(35) S]-GTPγS binding, or effects on equilibrium binding of [(3) H]-NMS and ACh. The in vivo actions of LY2033298 were investigated in a mouse model of amphetamine-induced locomotor activity. The function of LY2033298 was examined in combination with ACh, oxotremorine or xanomeline.

KEY RESULTS

LY2033298 had similar affinities for the human and mouse M(4) mAChRs. However, LY2033298 had a lower positive co-operativity with ACh at the mouse relative to the human M(4) mAChR. At the mouse M(4) mAChR, LY2033298 showed higher co-operativity with oxotremorine than with ACh or xanomeline. The different degrees of co-operativity between LY2033298 and each agonist at the mouse relative to the human M(4) mAChR necessitated the co-administration of LY2033298 with oxotremorine in order to show in vivo efficacy of LY2033298.

CONCLUSIONS AND IMPLICATIONS

These results provide evidence for species variability when comparing the allosteric interaction between LY2033298 and ACh at the M(4) mAChR, and also highlight how the interaction between LY2033298 and different orthosteric ligands is subject to 'probe dependence'. This has implications for the validation of allosteric modulator actions in vivo.

Impaired insight in patients with newly diagnosed nonaffective psychotic disorders with and without deficit features

Patients with schizophrenia who have primary, enduring negative symptoms, or the deficit syndrome, have poorer psychosocial functioning but lesser clinical distress compared with nondeficit patients. Poor awareness of impairment in patients with deficit schizophrenia may contribute to this seeming contradiction. We hypothesized that poor insight would be present early in the course of illness in deficit patients, and that those with deficit features would have greater impairment in insight than those without deficit features. One-hundred one first-episode patients with nonaffective psychotic disorders were categorized into deficit (n=31) and nondeficit (n=70) groups. The deficit patients had significantly poorer insight than nondeficit patients when rated using a self-report questionnaire, and nearly significantly poorer insight rated by clinical researchers. Further, this effect remained for self-rated insight and reached statistical significance for researcher-rated insight after controlling for positive, negative, and general psychopathology symptoms. These results suggest that the treatment of deficit patients may be particularly complicated by poor insight.

Methodological issues in negative symptom trials

Individuals from academia, the pharmaceutical industry, and the US Food and Drug Administration used a workshop format to discuss important methodological issues in the design of trials of pharmacological agents for improving negative symptoms in schizophrenia. The issues addressed included the need for a coprimary functional measure for registration trials; the characteristics of individuals who should enter negative symptom trials; the optimal duration for a proof-of-concept or registration trial; the optimal design of a study of a broad-spectrum agent that treats both positive and negative symptoms or a co-medication that is added to an antipsychotic; the relative strengths and weaknesses of available instruments for measuring negative symptoms; the definition of clinically meaningful improvement for these trials; and whether drugs can be approved for a subdomain of negative symptoms.

Sildenafil adjunctive therapy to risperidone in the treatment of the negative symptoms of schizophrenia: a double-blind randomized placebo-controlled trial

RATIONAL

It has been suggested that phosphodiesterase 5 inhibitors such as sildenafil may be effective in the treatment of negative symptoms of schizophrenia.

OBJECTIVE

This study was designed to investigate the effect of sildenafil added to risperidone as augmentation therapy in patients with chronic schizophrenia and prominent negative symptoms in a double-blind and randomized clinical trial.

METHODS

Eligible participants in the study were 40 patients with chronic schizophrenia with ages ranging from 18 to 45 years. All patients were inpatients and were in the active phase of the illness and met DSM-IV-TR criteria for schizophrenia. Patients were allocated in a random fashion: 20 to risperidone (6 mg/day) plus sildenafil (75 mg/day) and 20 to risperidone (6 mg/day) plus placebo. The principal measure of outcome was Positive and Negative Syndrome Scale (PANSS).

RESULTS

Although both protocols significantly decreased the score of the positive, negative, and general psychopathological symptoms over the trial period, the combination of risperidone and sildenafil showed a significant superiority over risperidone alone in decreasing negative symptoms and PANSS total scores over the 8-week trial (between-subjects factor; F = 4.77, df = 1; P = 0.03; F = 5.91, df = 1, P = 0.02 respectively).

CONCLUSION

Therapy with 75 mg/day of sildenafil was well tolerated, and no clinically important side effects were observed. The present study indicates sildenafil as a potential adjunctive treatment strategy for treatment of negative symptoms of schizophrenia. This trial is registered with the Iranian Clinical Trials Registry (IRCT1138901151556N11).

Effect of group music activity as an adjunctive therapy on psychotic symptoms in patients with acute schizophrenia

The effect of group music activity as an adjunctive therapy on psychotic symptoms was evaluated in 67 patients with schizophrenia from an acute psychiatric ward of a regional hospital in south Taiwan. A pretest-posttest, two-group repeated measures design was used. The experimental group received 50-minute sessions of group musical activity five times a week for 2 weeks in addition to standard care. The severity of psychotic symptoms was assessed using the Brief Psychiatric Rating Scale (BPRS). Group music activity significantly reduced the scores in total and subscales of the BPRS in patients with acute schizophrenia.

A double-blind, randomized, and placebo-controlled trial of buspirone added to risperidone in patients with chronic schizophrenia

OBJECTIVE

The role of partial agonism at 5-HT1A receptors in general and of buspirone in particular remains unclear in the treatment of negative symptoms of schizophrenia. This study was designed to investigate the effect of buspirone added to risperidone as augmentation therapy in patients with chronic schizophrenia and prominent negative symptoms in a double-blind randomized clinical trial.

METHODS

The participants were 31 men and 15 women aged 19 to 44 years who were inpatients at 2 psychiatric teaching hospitals in Iran. All patients were inpatients and were in the active phase of the illness and met the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria for schizophrenia. Patients were allocated in a random fashion: 23 patients to risperidone at 6 mg/d plus buspirone at 60 mg/d and 20 patients to risperidone at 6 mg/d plus placebo. The outcome was measured using the Positive and Negative Syndrome Scale.

RESULTS

The buspirone group had significantly greater improvement in the negative symptoms and positive general psychopathology subscales and Positive and Negative Syndrome Scale total scores over the 8-week trial. Therapy with 60 mg of buspirone per day was well tolerated, and no clinically important adverse effects were observed.

CONCLUSIONS

The present study indicates buspirone as a potential adjunctive treatment strategy for the treatment of schizophrenia, in particular, negative symptoms. Nevertheless, results of larger controlled trials are needed before recommendation for a broad clinical application can be made. This trial is registered with the Iranian Clinical Trials Registry (IRCT138712051556N8).

A post hoc analysis of negative symptoms and psychosocial function in patients with schizophrenia: a 40-week randomized, double-blind study of ziprasidone versus haloperidol followed by a 3-year double-blind extension trial

Schizophrenia is a persistent, lifelong illness such that enduring functional improvements may only occur over the course of years [corrected].This post hoc analysis in stable outpatients with schizophrenia investigated the negative symptom efficacy and treatment outcomes of ziprasidone (80-160 mg/d given twice a day, mean modal dose of 112 mg/d; and 80-120 mg/d given every day, mean modal dose of 96 mg/d) versus haloperidol (5-20 mg/d, mean modal dose of 12 mg/d) in a randomized, 40-week, double-blind study, followed by a double-blind continuation trial that extended up to 156 additional weeks. Symptomatic and functional recovery criteria were met when subjects attained both negative symptom remission and adequate psychosocial functioning based on the 4 Quality-of-Life subscales (instrumental role, interpersonal relations, participation in community, and intrapsychic foundations). Negative symptom remission (P = 0.005), as well as sustained adequate functioning (6 months) in instrumental role (P = 0.04) and participation in community (P = 0.02), was associated with significantly shorter time to remission in the ziprasidone 80 to 160 mg group than in the haloperidol group, as was the combination of symptomatic and functional recovery during the 196-week double-blind study period. A similar pattern was observed for the ziprasidone 80 to 120 mg group, which showed significant differences versus haloperidol in negative symptom remission and instrumental role functioning (but not other Quality-of-Life subscale measures). The clinically relevant outcome differences detected in this post hoc exploratory analysis support the potential for both enhanced remission in negative symptoms and psychosocial recovery during long-term treatment with an atypical agent and add to our understanding regarding the degree to which negative symptom remission can be attained in the maintenance phase.

Neural correlates of reward processing in schizophrenia--relationship to apathy and depression

The present study employs a new framework to categorise the heterogeneous findings on the relationship between impaired reward processing and negative and affective symptoms of schizophrenia. Based on previous behavioural and neuroimaging studies we postulate that "wanting" (i.e. anticipation) of a reward is specifically related to apathy, whereas "liking" (i.e. hedonic impact) is related to anhedonia and depression--symptoms commonly observed in schizophrenia. Fifteen patients with schizophrenia or schizoaffective disorder treated with atypical antipsychotic drugs and fifteen healthy controls performed a probabilistic monetary incentive delay task while undergoing functional magnetic resonance imaging. At the group level we found no significant differences between patients and controls in neural activation during anticipation or receipt of a reward. However, in patients with schizophrenia specific relationships between ventral-striatal activation and symptoms were observed. Ventral-striatal activation during reward anticipation was negatively correlated with apathy, while activation during receipt of reward was negatively correlated with severity of depressive symptoms. These results suggest that the link between negative symptoms and reward anticipation might specifically relate to apathy, i.e. a lack of motivation and drive. Impaired hedonic reward processing might contribute to the development of depressive symptoms in patients with schizophrenia, but it is not directly associated with self-rated anhedonia. These results indicate the necessity of more specifically differentiating negative and affective symptoms in schizophrenia in order to understand the role of the reward system in their pathogenesis.

Negative symptoms and concomitant attention deficits in schizophrenia: associations with prospective assessments of anxiety, social dysfunction, and avoidant coping

BACKGROUND

Negative symptoms are a significant barrier to function and may have a range of etiological roots and links to outcome. A previous study identified a subgroup of patients with schizophrenia who had both higher levels of negative symptoms and relatively poorer attentional function who had uniquely lower self-esteem and greater internalized stigma.

AIMS

To determine whether participants previously classified as having High Negative/Poorer Attention would continue to have lower self-esteem, higher self-stigma, and also higher levels of anxiety and avoidant coping 5 months later.

METHOD

Participants were 77 (77.8%) of the original 99 participants who completed follow-up procedures.

RESULTS

The High Negative/Poorer Attention group had significantly poorer social functioning, lower appraisal of their competence, higher levels of anxiety, and a higher preference for ignoring stressors five months after classification.

CONCLUSIONS

Negative symptoms with concomitant attention deficits may lead to more social and psychological dysfunction than negative symptoms or attention deficits alone. Individuals with both high levels of negative symptoms and poor attention may represent a meaningful subgroup with unique psychosocial difficulties that persist over time.

The effect of mirtazapine add on therapy to risperidone in the treatment of schizophrenia: a double-blind randomized placebo-controlled trial

It has been reported that mirtazapine would be helpful for treating negative symptoms in schizophrenia. Nevertheless, the results are contradictory so far. This study was designed to investigate the effect of mirtazapine added to risperidone as augmentation therapy in patients with chronic schizophrenia and prominent negative symptoms in a double-blind and randomized clinical trial. Eligible participants in the study were 40 patients with chronic schizophrenia with ages ranging from 19 to 49 years. All patients were inpatients and were in the active phase of the illness, and met DSM-IV-TR criteria for schizophrenia. Patients were allocated in a random fashion 20 to risperidone 6 mg/day plus mirtazapine 30 mg/day and 20 to risperidone 6 mg/day plus placebo. The principal measure of the outcome was Positive and Negative Syndrome Scale (PANSS). The mirtazapine group had significantly greater improvement in the negative symptoms and PANSS total scores over the eight-week trial. Therapy with 30 mg/day of mirtazapine was well tolerated and no clinically important side effects were observed. The present study indicates mirtazapine as a potential combination treatment strategy for chronic schizophrenia particularly for negative symptoms.

Progress in defining optimal treatment outcome in schizophrenia

Historically, schizophrenia has been associated with early-onset, persistent symptoms, and progressive decline accompanied by poor functional recovery. The advent of effective drugs in the 1950s improved symptom control, at least from the standpoint of positive features (e.g. hallucinations, delusions). However, even here the response was limited and efficacy in other symptom domains (cognitive, deficit/negative) was minimal. With clozapine as the prototype, the second-generation antipsychotics arrived in the 1990s with claims of improved tolerability, as well as greater and broader clinical efficacy, all of which was to translate to gains in functional outcome and quality of life. The capacity of these drugs to effect such changes has since been tempered, but it remains that the research and hope generated served as an impetus to redefine outcomes. A medical-based model, centred on pharmacotherapy and symptom resolution, has given way to a re-conceptualization of schizophrenia and treatment goals. There is a clearer distinction between clinical and functional outcomes, and, with this, greater attention has been given to these other symptom domains that curtail improvement in the latter. At the same time, a concerted shift to shared decision making has underscored quality-of-life issues that benefit from, but cannot be guaranteed by, either clinical or functional improvement. To this end, the field has now embraced a recovery model that is seen as a process, multidimensional and individualized, rather than dichotomous and symptom driven.

Schizophrenia

Schizophrenia is still one of the most mysterious and costliest mental disorders in terms of human suffering and societal expenditure. Here, we focus on the key developments in biology, epidemiology, and pharmacology of schizophrenia and provide a syndromal framework in which these aspects can be understood together. Symptoms typically emerge in adolescence and early adulthood. The incidence of the disorder varies greatly across places and migrant groups, as do symptoms, course, and treatment response across individuals. Genetic vulnerability is shared in part with bipolar disorder and recent molecular genetic findings also indicate an overlap with developmental disorders such as autism. The diagnosis of schizophrenia is associated with demonstrable alterations in brain structure and changes in dopamine neurotransmission, the latter being directly related to hallucinations and delusions. Pharmacological treatments, which block the dopamine system, are effective for delusions and hallucinations but less so for disabling cognitive and motivational impairments. Specific vocational and psychological interventions, in combination with antipsychotic medication in a context of community-case management, can improve functional outcome but are not widely available. 100 years after being so named, research is beginning to understand the biological mechanisms underlying the symptoms of schizophrenia and the psychosocial factors that moderate their expression. Although current treatments provide control rather than cure, long-term hospitalisation is not required and prognosis is better than traditionally assumed.

D1 receptor antagonist-induced long-term depression in the medial prefrontal cortex of rat, in vivo: an animal model of psychiatric hypofrontality

The objective of the following experiment was to induce a pathogenic hypofrontal condition by administering a dopamine-1 receptor (D(1)R) antagonist to rats. The pathophysiological effect of this manipulation upon glutamate-based long-term potentiation (LTP) in the medial prefrontal cortex (mPFC) was examined in vivo. Subjects were surgically implanted with stimulating electrodes into the corpus callosum and recording electrodes into the mPFC. High-frequency stimulation (HFS) was combined with the administration of the selective D(1)R family agonist A68930 hydrochloride (0.4 mg/kg/mL) and the selective D(1)R family antagonist SKF 83566 (0.15 mg/kg/mL). The administration of SKF 83566 hydrobromide prevented mPFC LTP, and resulted in HFS-induced long-term depression. This indicates that D(1)R activation is necessary for the induction of mPFC glutamate-based LTP. This is supported by our finding that the administration of A68930 hydrochloride combined with HFS induced LTP comparable with saline control levels, suggesting that D(1)R activation is necessary for the induction of baseline levels of mPFC LTP. Given that the mPFC governs executive behaviours that are subserved by LTP, such as working memory, these findings are relevant for the study of psychopathological conditions in which hypodopaminergic conditions exist in the mPFC and are correlated with psychiatric symptomotology, such as drug addiction and schizophrenia.

HTR2A A-1438G/T102C polymorphisms predict negative symptoms performance upon aripiprazole treatment in schizophrenic patients

RATIONALE

Aripiprazole acts as a partial agonist at dopamine D2 and D3 and serotonin 1A receptors and as an antagonist at serotonin 2A receptors (HTR2A). Since aripiprazole acts as an antagonist at HTR2A, genetic variants of HTR2A may be important in explaining variability in response to aripiprazole.

OBJECTIVES

This study investigated whether the efficacy of aripiprazole can be predicted by functional HTR2A A-1438G/T102C polymorphisms (rs63311/rs6313) as modified by clinical factors in Han Chinese hospitalized patients with acutely exacerbated schizophrenia.

MATERIALS AND METHODS

After hospitalization, the patients (n = 128) were given a 4-week course of aripiprazole. Patients were genotyped for HTR2A A-1438G/T102C polymorphisms via the restriction fragment length polymorphism method. Clinical factors such as gender, age, duration of illness, education level, diagnostic subtype, and medication dosage were noted as well. The researchers measured psychopathology biweekly, using the Positive and Negative Syndrome Scale (PANSS). A mixed model regression approach (SAS Proc MIXED) was used to analyze the effects of genetic and clinical factors on PANSS performance after aripiprazole treatment.

RESULTS

We found that the GG/CC genotype group of HTR2A A-1438G/T102C polymorphisms predicts poor aripiprazole response specifically for negative symptoms. In addition, the clinical factors, including dosage of aripiprazole, age, duration of illness, and diagnostic subtype, were found to influence PANSS performance after aripiprazole treatment.

CONCLUSIONS

The data suggest HTR2A A-1438G/T102C polymorphisms may predict negative symptoms performance upon aripiprazole treatment in schizophrenic patients as modified by clinical factors.

Negative symptoms and concordant impairments in attention in schizophrenia: associations with social functioning, hope, self-esteem and internalized stigma

Research has suggested that negative symptoms in schizophrenia may be closely linked to impairments in schizophrenia. Research on the strength and nature of this association has been equivocal, however. One possible explanation is that there are two distinct groups of persons with negative symptoms: those with and those without attentional impairments. To examine this question we performed a cluster analysis on 99 adults with schizophrenia or schizoaffective disorder on the basis of their level of negative symptoms and performance on a continuous performance task. Four groups were found: low negative/relatively better attention (n=31), low negative/relatively poor attention (n=20), high negative/ relatively poor attention (n=28), and high negative/relatively better attention (n=20). To determine whether these groups differed meaningfully from one another, we next compared their performance on other assessments of positive symptoms, social function, self-esteem and stigma. A MANOVA found significant differences (Wilks' lambda F=3.2; p<.01) with the high negative/poor attention group having poorer self esteem and greater acceptance of stigma than the other three groups and the high negative/relatively better attention group having higher levels of positive symptoms than the other groups. Implications for research and treatment are discussed.

The relationship between symptom severity and regional cortical and grey matter volumes in schizophrenia

OBJECTIVE

To investigate the relationship between symptom severity and cortical and grey matter volumes in schizophrenia.

METHOD

Fifty-three outpatients with schizophrenia were assessed by the Scale for the Assessment of Negative Symptoms and the Scale for the Assessment of Positive Symptoms. Symptoms were grouped into five factors (negative, relational, inattention, disorganization, and reality distortion). Cortical and lobar grey matter volumes within all regions of the brain were obtained from magnetic resonance images using two independent software tools. The relationships between brain volumes and symptom factors were analyzed by partial correlations controlling for age, gender, dose and type of antipsychotic medication, and intracranial volume.

RESULTS

Negative symptoms were generally associated with larger cortical volumes in all regions of the brain, and the relational and inattention factors were associated with larger frontal grey matter volumes. The reality distortion factor was associated with smaller cortical volumes throughout the brain and with smaller frontal and temporal grey matter volumes.

CONCLUSION

Differential contribution of positive and negative symptoms to variation in cortical and grey matter volumes indicates separate neurobiological mechanisms underlying the two major symptom domains in schizophrenia.

Relative contribution of antipsychotics, negative symptoms and executive functions to social functioning in stable schizophrenia

The purpose of this study was to examine the relative contributions of antipsychotic medication, negative symptoms and executive functions to impairment in social functioning in a sample of outpatients with stable schizophrenia. One-hundred and sixty-eight consecutive outpatients with stable schizophrenia were enrolled in a cross-sectional study. We performed a path analysis using multiple regression technique in order to assess the specific effect of antipsychotic type (first-generation antipsychotics versus second-generation antipsychotics) on social functioning and the possible mediating role of executive functions and negative symptoms. Our findings suggested that (i) second generation antipsychotics (SGAs) use predicted better social functioning (Beta=.24, p=.003) and better executive functions (Beta=.25, p=.003); conversely SGAs use was not associated with lesser negative symptoms (Beta=.00, p=.981); (ii) impaired executive functions and severity of negative symptoms were associated with worse social functioning (Beta=.19, p=.016; Beta=.28, p=.001); (iii) when we inserted in the model Positive and Negative Syndrome Scale - Negative Symptom subscale (PANSS-N) and Wisconsin Card Sorting Test - number of achieved sorting categories (WCST-cat), the former failed to show a mediation effect, while the latter seemed to mediate partially the effect of SGAs on social functioning. Taken together, the present results suggest that it is critical to examine individually executive functions and negative symptoms because they seem to relate to social functioning in different and independent ways and thus might represent separable treatment targets. Furthermore, social functioning appears a complex outcome multiply determined with no single predictor variable explaining a sufficient amount of variance.

Dose-response relationship in music therapy for people with serious mental disorders: systematic review and meta-analysis

Serious mental disorders have considerable individual and societal impact, and traditional treatments may show limited effects. Music therapy may be beneficial in psychosis and depression, including treatment-resistant cases. The aim of this review was to examine the benefits of music therapy for people with serious mental disorders. All existing prospective studies were combined using mixed-effects meta-analysis models, allowing to examine the influence of study design (RCT vs. CCT vs. pre-post study), type of disorder (psychotic vs. non-psychotic), and number of sessions. Results showed that music therapy, when added to standard care, has strong and significant effects on global state, general symptoms, negative symptoms, depression, anxiety, functioning, and musical engagement. Significant dose-effect relationships were identified for general, negative, and depressive symptoms, as well as functioning, with explained variance ranging from 73% to 78%. Small effect sizes for these outcomes are achieved after 3 to 10, large effects after 16 to 51 sessions. The findings suggest that music therapy is an effective treatment which helps people with psychotic and non-psychotic severe mental disorders to improve global state, symptoms, and functioning. Slight improvements can be seen with a few therapy sessions, but longer courses or more frequent sessions are needed to achieve more substantial benefits.

Effect of ritanserin, a 5HT2A/2C antagonist, on negative symptoms of schizophrenia: a double-blind randomized placebo-controlled study

It was reported that ritanserin, a 5HT2A/2C antagonist, improves negative symptoms when added to neuroleptics in inpatients with predominantly negative symptoms. Nevertheless, the results of published studies are contradictory so far. This study was designed to investigate the effect of ritanserin added to risperidone as augmentation therapy in patients with chronic schizophrenia and prominent negative symptoms in a double blind and randomized clinical trial. Eligible participants in this study were 40 patients with chronic schizophrenia. All patients were inpatients and were in the active phase of the illness, and met DSM-IV-TR criteria for schizophrenia. Patients were allocated in a random fashion, 20 to risperidone 6 mg/day plus ritanserin 12 mg/day (6 mg bid) and 20 to risperidone 6 mg/day plus placebo. The principal measure of the outcome was Positive and Negative Syndrome Scale (PANSS). Although both protocols significantly decreased the score of the positive, negative and general psychopathological symptoms over the trial period, the combination of risperidone and ritanserin showed a significant superiority over risperidone alone in decreasing negative symptoms and PANSS total scores. The present study indicates ritanserin as a potential adjunctive treatment strategy for the negative symptoms of schizophrenia. Nevertheless, results of larger controlled trials are needed, before recommendation for a broad clinical application can be made.

Antipsychotics for the treatment of schizophrenia: likelihood to be helped or harmed, understanding proximal and distal benefits and risks

Benefit-risk decisions are the central part of the philosophy of evidence-based medicine. Although number needed to treat (NNT) and number needed to harm (NNH) can quantify differences between two antipsychotics in terms of benefits and risks for the treatment of schizophrenia, these benefits and risks can take on greatly differing degrees of importance or relevance depending on the subjective point of view of the patient and clinician, baseline risks, severity of the underlying illness, as well as the time horizon when these effects emerge. The metric of likelihood to be helped or harmed, the ratio NNH to NNT, can be helpful in quantifying the benefit:risk ratio, provided that the outcomes are carefully matched in terms of both importance to the clinician and the patient and whether they are proximal or distal. The examples provided are extensions to the initially published NNT and NNH analyses conducted by the first author.

Longitudinal progression of negative symptoms in schizophrenia: a new look at an old problem

OBJECTIVE

Longitudinal analysis is crucial in determining the ability of new interventions to successfully reduce negative symptoms in schizophrenia. However, there are still conflicting reports as to whether there are significant treatment effects on these symptoms and the extent of these effects. We examine the possible effects of analysis method on these questions.

METHODS

We use generalized linear mixed models (GLMM) to assess the change in specific negative symptom items following treatment changes in two separate cohorts of schizophrenia patients, one chronic and one first episode.

RESULTS

Both data sets indicate that examining the change in prevalence of moderate to severe symptoms provides a useful estimate of the effect size associated with changes in treatment that often differs from that given using analysis of means.

CONCLUSIONS

The use of categorical longitudinal methods may be critical to determining the responsiveness of negative symptoms to treatment as well as determining the stability of these symptoms over time.

A review of repetitive transcranial magnetic stimulation use in the treatment of schizophrenia

Patients with schizophrenia often fail to respond to standard antipsychotic medications or have a partial treatment response. Few treatment options are available for these patients. Repetitive transcranial magnetic stimulation (rTMS) was developed and investigated over the last 10 years as a potential treatment option for various psychiatric conditions. Increasingly, studies are focusing on potential applications of rTMS in schizophrenia. To date, most of these studies were symptom-specific rather than focused on the treatment of the disorder in general. The most extensive literature focuses on the use of low-frequency stimulation to attempt to disrupt or reduce the intensity of persistent refractory auditory hallucinations. This research tends to suggest that rTMS could have a role in this subset of patients. There is also preliminary but limited evidence that rTMS could have a role in reducing the negative symptoms of schizophrenia and perhaps in augmenting cognitive function. These findings also highlight the pressing need for further research including multisite studies to confirm the value of these options.

Disturbances in social interaction occur along with pathophysiological deficits following sub-chronic phencyclidine administration in the rat

A sub-chronic administration of phencyclidine to the rat brings about enduring pathophysiological and cognitive changes that resemble some features of schizophrenia. The present study aimed to determine whether the behavioural consequence of this phencyclidine regime extends to a long-term disruption of social interaction that might provide a parallel with some negative symptoms of the disease. Rats were treated with phencyclidine (2mg/kg bi-daily for 1 week) or vehicle followed by a drug-free period. Social interaction was assessed 24h, 1 week, 3 weeks and 6 weeks post-treatment. A long-lasting disturbance of social behaviour was observed in the phencyclidine group, namely more contact and non-contact interaction with an unfamiliar target rat at all time points. Six weeks post-phencyclidine, analysis of brains showed a reduction in expression of parvalbumin immunoreactive neurons in the hippocampus with significant reductions localised to the CA1 and dentate gyrus regions. These results show that sub-chronic phencyclidine produces long-lasting disruptions in social interaction that, however, do not model the social withdrawal seen in patients with schizophrenia. These disturbances of social behaviour may be associated with concurrent pathophysiological brain changes.