Characteristics of responders and non-responders to risperidone monotherapy or placebo in co-occurring bipolar disorder and anxiety disorder

Comparative efficacy and safety of different drugs for bipolar disorder complicated with anxiety disorder: A protocol for systematic review and network meta-analysis

BACKGROUND

Nowadays, there are some randomized controlled trials (RCTs) to explore the effectiveness of drug therapy for bipolar disorder with anxiety disorders. However, due to lack of sufficient data, there are currently no good treatment recommendations. The purpose of this network meta-analysis is to compare the efficacy and safety of different drugs for bipolar disorder complicated with anxiety disorders to provide evidence to support clinical practice and guidelines development.

METHODS

A systematic literature search will be performed in the Cochrane Library, PubMed, EMBASE, and Web of Science from inception to July 2020. RCTs that compared the efficacy and safety of different drugs for bipolar disorder complicated with anxiety disorders will be included. Two reviewers will independently search and select the studies, extract the data, and assess the risk of bias. We will assess the risk of bias of included RCTs using the Cochrane risk of bias tool. The WinBUGS 1.4.3 software will be used to perform the network meta-analysis, and the result figures will be generated by STATA 15.0 software. In addition, we will use the Grading of Recommendations Assessment, Development and Evaluation (GRADE) to assess the quality of evidence.

RESULTS

This study will systematically compare the efficacy and safety of different drugs for bipolar disorder complicated with anxiety disorders. The results of this network meta-analysis will be submitted to a peer-reviewed journal for publication.

CONCLUSION

Our study will provide evidence for the drug therapy of patients with bipolar disorder complicated with anxiety disorders, and provide suggestions for clinical practice or guidelines.

INPLASY REGISTRATION NUMBER

INPLASY202070132.

Between placebo and nocebo: Response to control treatment is mediated by amygdala activity and connectivity

BACKGROUND

In experimental placebo and nocebo studies, neutral control treatments are often administered for comparison with active treatments, but are of little interest, as, on average, they result in little change. Yet, when considered at an individual level, they fluctuate between baseline and subsequent measurements and may reveal important information about participants' placebo/nocebo responding tendencies.

METHODS

In a paradigm involving application of creams paired with positive, negative and neutral expectations, some subjects rated identical stimuli in the neutral condition as more painful while others as less painful after treatment with inert cream. We divided subjects into two groups based on the median split in these pre-post responses in the neutral control condition, and investigated (a) fMRI signal differences (post minus pre) between the two groups in neutral condition, and (b) seed-based resting state connectivity of the bilateral amygdala, known to be involved in emotional self-regulation, as well as ambiguous stimulus processing and aversive learning.

RESULTS

The results suggested that subjects who rated the same pain stimuli after treatment with explicitly neutral cream as more painful showed stronger fMRI activation of the amygdala during the experiment and had higher connectivity between the left amygdala and the striatum at rest. Neutral pre-post changes predicted behavioural placebo/nocebo response in this and two independent datasets.

CONCLUSION

These findings suggest that measuring pre-post change in the neutral control condition might provide important information about subjects' individual differences in placebo/nocebo response.

SIGNIFICANCE

Pre-post changes in pain ratings in neutral conditions are modulated by amygdala activity and connectivity and can be used to predict placebo/nocebo responses.

Comorbid anxiety and social avoidance in treatment of severe childhood aggression: response to adding risperidone to stimulant and parent training; mediation of disruptive symptom response

OBJECTIVE

In the four-site Treatment of Severe Childhood Aggression (TOSCA) study, addition of risperidone to stimulant and parent training moderately improved parent-rated disruptive behavior disorder (DBD) symptoms. This secondary study explores outcomes other than DBD and attention-deficit/hyperactivity disorder (ADHD) as measured by the Child and Adolescent Symptom Inventory-4R (CASI-4R).

METHODS

A total of 168 children ages 6-12 with severe aggression (physical harm), DBD, and ADHD were randomized to parent training plus stimulant plus placebo (basic treatment) or parent training plus stimulant plus risperidone (augmented treatment) for 9 weeks. All received only parent training plus stimulant for the first 3 weeks, then those with room for improvement received a second drug (placebo or risperidone) for 6 weeks. CASI-4R category item means at baseline and week 9 were entered into linear mixed-effects models for repeated measures to evaluate group differences in changes. Mediation of the primary DBD outcome was explored.

RESULTS

Parent ratings were nonsignificant with small/negligible effects, but teacher ratings (n=46 with complete data) showed significant augmented treatment advantage for symptoms of anxiety (p=0.013, d=0.71), schizophrenia spectrum (p=0.017, d=0.45), and impairment in these domains (p=0.02, d=0.26), all remaining significant after false discovery rate correction for multiple tests. Improvement in teacher-rated anxiety significantly (p=0.001) mediated the effect of risperidone augmentation on the primary outcome, the Disruptive-total of the parent-rated Nisonger Child Behavior Rating Form.

CONCLUSIONS

Addition of risperidone to parent training plus stimulant improves not only parent-rated DBD as previously reported, but also teacher-rated anxiety-social avoidance. Improvement in anxiety mediates improvement in DBD, suggesting anxiety-driven fight-or-flight disruptive behavior with aggression, with implications for potential treatment strategies. Clinicians should attend to possible anxiety in children presenting with aggression and DBD.

CLINICAL TRIAL REGISTRY

Treatment of Severe Childhood Aggression (The TOSCA Study). NCT00796302. clinicaltrials.gov.

Should placebo be used routinely for chronic pain in older people?

As research expands our understanding of underlying placebo mechanisms, interest turns to the clinical application of placebos. Whether placebos are appropriate and effective in the management of chronic pain in older people deserves considerable attention. The evidence suggests that adults of any age are responsive to placebos, and that placebo treatments can be effective for many conditions prevalent in older people. Though placebos in general already seem to be used with some regularity in medical practice, the use of placebos alone for chronic pain is probably unjustified unless other treatments are inadvisable or have been exhausted. However maximising the mechanisms that underpin placebo analgesia such as expectancy or the psychosocial context should be encouraged and would be considered a feature of good clinical practice. It would also be anticipated that older people may see an additional benefit with placebo treatments when such treatments reduce existing or planned medication regimes, as older people typically experience more comorbidities, increased susceptibility to adverse drug reactions, and altered pharmacological responses to drugs. Further research is still needed in placebo-related treatment paradigms for the management of chronic pain in older people.