Anxiety in Informal Dementia Carers: A Meta-Analysis of Prevalence.

Much of the carer literature has focused on depression and burden as primary outcomes and anxiety appear somewhat neglected. Providing evidence on the prevalence of carer anxiety is critical as it can enhance awareness among professionals, which in turn can lead to improved access to efficacious treatments. This meta-analysis updated the previous review conducted in 2007 to estimate the up-to-date prevalence of anxiety in informal carers for people with dementia. Literature searches were conducted in databases of published and unpublished literature. Events and sample size data were pooled using a random effects model to obtain an overall prevalence percentage. A total of 10 studies were included, resulting in a pooled estimate of anxiety prevalence at 32.1% (95% confidence interval: 20.6%-46.2%, P = .01). Significant heterogeneity was found, which was not reduced following sensitivity analysis. This study suggests anxiety is a prevalent difficulty experienced by dementia carers. Additional research recommendations and clinical implications are discussed.

A meta-analysis of low-intensity cognitive behavioral therapy-based interventions for dementia caregivers.

OBJECTIVES: This study aimed to review the effectiveness of low-intensity cognitive behavioral therapy (CBT)-based interventions for informal dementia caregivers when compared to non-active control conditions. DESIGN: Literature searches were conducted in databases of published (PsycINFO, MEDLINE, CINAHL, Scopus) and unpublished (Open Grey, ISRCTN registry, ClinicalTrials.gov, ProQuest) literature. Individual meta-analyses were conducted for each outcome variable. Pooled intervention effect estimates were calculated as Hedge's g using a random-effects model. INCLUDED STUDIES: Studies examining the effect of low-intensity CBT-based interventions for informal caregivers for people with any progressive dementia were included. Randomized controlled trials and controlled clinical trials were included. MEASUREMENTS: Outcomes included the psychological variables of anxiety, depression, burden, and distress (defined as stress or strain). RESULTS: A total of five studies reported anxiety outcomes, 12 reported on depression, three reported on burden, and six reported distress outcomes. Results demonstrated a significant effect of low-intensity CBT-based interventions in reducing all examined psychological difficulties. Small effect sizes were found for anxiety (g = 0.35), depression (g = 0.27), and distress (g = 0.33). A medium effect was found for burden (g = 0.53). CONCLUSIONS: The results provide initial support for low-intensity CBT-based interventions for dementia caregivers. Clinical implications and research recommendations are explored. Strengths and limitations of the study are discussed.

An electrophysiological measure of visual short-term memory capacity within and across hemifields.

Recent electrophysiological research has identified a specific contralateral correlate of the contents of visual short-term memory (VSTM). This posterior contralateral delay activity (CDA) persists during the retention period, and its amplitude is modulated by the number of items held at any one time. Here we show that, despite the contralateral nature of this activity, its amplitude is modulated by the number of objects from both hemifields. When objects from one side of the visual field are held in memory, CDA activity increased for arrays of one, two, and three objects, but stopped getting larger for arrays of four objects. However, when objects from both sides are memorized at the same time, CDA activity reached its asymptotic limit for arrays of two objects per side. These results suggest that, in spite of being contralaterally organized, VSTM is limited by the number of objects from both hemifields.

D-cycloserine enhances memory consolidation in the plus-maze retest paradigm.

Prior undrugged exposure to the elevated plus-maze (EPM) alters future behavioral strategy as well as responsivity to conventional anxiolytic agents. This EPM retest phenomenon appears to be dependent upon learning the spatial configuration of the maze on initial exposure and, in particular, the location of the relatively safe enclosed arms. As posttraining administration of the glycineB receptor partial agonist, D-cycloserine (DCS), has been shown to enhance the consolidation of many forms of memory, we have examined the effects of this compound on the EPM retest effect in male mice. The results of Experiment 1 confirmed that 5 min undrugged exposure to the EPM completed abolishes the anxiolytic efficacy of chlordiazepoxide (CDP; 15 mg/kg) on 24 hr retest. In Experiment 2, posttraining administration of DCS (7.5 and 15 mg/kg), but not CDP (15 mg/kg) or DCS (30 mg/kg), significantly and selectively increased time spent in the enclosed arms (and reciprocally decreased open arm exploration) on 24 hr retest, a finding consistent with an enhancement of consolidation. Experiment 3 used a modified EPM retest protocol to assess the effects of posttraining DCS (15 mg/kg) on behavioral responses to CDP (15 mg/kg) challenge on 24 hr retest. Using a 1-min prior exposure regimen that did not compromise the anxiolytic efficacy of CDP in control mice, the results showed that posttraining administration of DCS abolished the anxiolytic response to CDP challenge. These data strongly suggest that the EPM retest effect involves glycineB/NMDA receptor-dependent neuroplasticity. Further studies will be required to identify the neural circuitry involved.