Validation of the Athens Insomnia Scale for screening insomnia in South Korean firefighters and rescue workers.

PURPOSE: Sleep problems are a major cause of occupational stress in firefighters and rescue workers. We evaluated the psychometric properties of the Athens Insomnia Scale (AIS) among South Korean firefighters and rescue workers. METHODS: Structured clinical interviews and self-report questionnaires were administered to 221 firefighters and rescue workers. The Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS), Short-Form 36-item Health Survey (SF36), and Alcohol Use Disorder Identification Test-Consumption (AUDIT-C) were used to examine convergent and divergent validity. Test-retest reliability was calculated from a subsample (n = 24). Analysis of internal consistency, factor analysis, and receiver operator characteristic curve analysis were conducted. RESULTS: Cronbach's alpha was 0.88. The mean item-total correlation coefficient was 0.73. The test-retest reliability was excellent (ICC = 0.94). Significant correlations of the AIS with the PSQI, ISI, ESS, and SF36 confirmed convergent validity. Nonsignificant associations of the AIS with the AUDIT-C and socioeconomic status showed divergent validity. Factor analysis revealed a one-factor structure. For groups with different symptom severity, group-specific cutoff scores which may improve positive predictive values were suggested. CONCLUSIONS: The AIS may be a useful tool with good reliability and validity for screening insomnia symptoms in firefighters and rescue workers.

Efficacy and Safety of Tremella fuciformis in Individuals with Subjective Cognitive Impairment: A Randomized Controlled Trial.

The efficacy and safety of Tremella fuciformis (TF) as a nutritional supplement were assessed in individuals with subjective cognitive impairment (SCI). Seventy-five individuals with SCI were enrolled in an 8-week, randomized, double-blind, placebo-controlled trial of TF (600 mg/day, n = 30 or 1200 mg/day, n = 30) or placebo (n = 15). The primary outcome measure was changes in total scores of the subjective memory complaint questionnaire. The secondary outcome measures were changes in performance on short-term memory and executive functions, which were assessed using standardized cognitive tests. In addition, voxel-based morphometry was performed to examine the effects of TF on changes in gray matter volume. The individuals in the TF group showed greater improvements in the total scores on the subjective memory complaint questionnaire compared with those in the placebo group. There were also significantly greater improvements in short-term memory and executive functions in the TF group relative to the placebo group. Exploratory analysis demonstrated that there were significant group-by-visit interactions on the left precuneus, right supramarginal gyrus, right middle frontal gyrus, and right postcentral gyrus at corrected P < .05. Overall frequency of adverse events did not differ among high-dose TF (40.4%), low-dose TF (35.1%), and placebo groups (41.4%). The current findings suggest that TF could be safely administered to relieve subjective memory complaints and enhance cognition in individuals with SCI.

Effects of Creatine Monohydrate Augmentation on Brain Metabolic and Network Outcome Measures in Women With Major Depressive Disorder.

BACKGROUND: Creatine monohydrate (creatine) augmentation has the potential to accelerate the clinical responses to and enhance the overall efficacy of selective serotonin reuptake inhibitor treatment in women with major depressive disorder (MDD). Although it has been suggested that creatine augmentation may involve the restoration of brain energy metabolism, the mechanisms underlying its antidepressant efficacy are unknown. METHODS: In a randomized, double-blind, placebo-controlled trial, 52 women with MDD were assigned to receive either creatine augmentation or placebo augmentation of escitalopram; 34 subjects participated in multimodal neuroimaging assessments at baseline and week 8. Age-matched healthy women (n = 39) were also assessed twice at the same intervals. Metabolic and network outcomes were measured for changes in prefrontal N-acetylaspartate and changes in rich club hub connections of the structural brain network using proton magnetic resonance spectroscopy and diffusion tensor imaging, respectively. RESULTS: We found MDD-related metabolic and network dysfunction at baseline. Improvement in depressive symptoms was greater in patients receiving creatine augmentation relative to placebo augmentation. After 8 weeks of treatment, prefrontal N-acetylaspartate levels increased significantly in the creatine augmentation group compared with the placebo augmentation group. Increment in rich club hub connections was also greater in the creatine augmentation group than in the placebo augmentation group. CONCLUSIONS: N-acetylaspartate levels and rich club connections increased after creatine augmentation of selective serotonin reuptake inhibitor treatment. Effects of creatine administration on brain energy metabolism and network organization may partly underlie its efficacy in treating women with MDD.

Effects of Ganglioside on Working Memory and the Default Mode Network in Individuals with Subjective Cognitive Impairment: A Randomized Controlled Trial.

This randomized, double-blind, placebo-controlled trial examined whether the administration of ganglioside, an active ingredient of deer bone extract, can improve working memory performance by increasing gray matter volume and functional connectivity in the default mode network (DMN) in individuals with subjective cognitive impairment. Seventy-five individuals with subjective cognitive impairment were chosen to receive either ganglioside (330[Formula: see text][Formula: see text]g/day or 660[Formula: see text][Formula: see text]g/day) or a placebo for 8 weeks. Changes in working memory performance with treatment of either ganglioside or placebo were assessed as cognitive outcome measures. Using voxel-based morphometry and functional connectivity analyses, changes in gray matter volume and functional connectivity in the DMN were also assessed as brain outcome measures. Improvement in working memory performance was greater in the ganglioside group than in the placebo group. The ganglioside group, relative to the placebo group, showed greater increases in gray matter volume and functional connectivity in the DMN. A significant relationship between increased functional connectivity of the precuneus and improved working memory performance was observed in the ganglioside group. The current findings suggest that ganglioside has cognitive-enhancing effects in individuals with subjective cognitive impairment. Ganglioside-induced increases in gray matter volume and functional connectivity in the DMN may partly be responsible for the potential nootropic effects of ganglioside. The clinical trial was registered with ClinicalTrials.gov (identifier: NCT02379481).

Morphometric abnormalities of the lateral ventricles in methamphetamine-dependent subjects.

BACKGROUND: The presence of morphometric abnormalities of the lateral ventricles, which can reflect focal or diffuse atrophic changes of nearby brain structures, is not well characterized in methamphetamine dependence. The current study was aimed to examine the size and shape alterations of the lateral ventricles in methamphetamine-dependent subjects. METHODS: High-resolution brain structural images were obtained from 37 methamphetamine-dependent subjects and 25 demographically matched healthy individuals. Using a combined volumetric and surface-based morphometric approach, the structural variability of the lateral ventricles, with respect to extent and location, was examined. RESULTS: Methamphetamine-dependent subjects had an enlarged right lateral ventricle compared with healthy individuals. Morphometric analysis revealed a region-specific pattern of lateral ventricular expansion associated with methamphetamine dependence, which was mainly distributed in the areas adjacent to the ventral striatum, medial prefrontal cortex, and thalamus. CONCLUSIONS: Patterns of shape decomposition in the lateral ventricles may have relevance to the structural vulnerability of the prefrontal-ventral striatal-thalamic circuit to methamphetamine-induced neurotoxicity.