Disaster workers suffer from psychological distress not only through the direct experience of traumatic situations but also through the indirect process of aiding disaster victims. This distress, called secondary traumatic stress, is linked to dispositional empathy, which is the tendency for individuals to imagine and experience the feelings and experiences of others. However, the association between secondary traumatic stress and dispositional empathy remains understudied. To examine the relationship between dispositional empathy and mental health among disaster workers, we collected data from 227 Japan Ground Self-Defense Force personnel who engaged in international disaster relief activities in the Philippines following Typhoon Yolanda in 2013. The Impact of Event Scale-Revised and the Kessler Psychological Distress Scale were used to evaluate posttraumatic stress responses (PTSR) and general psychological distress (GPD), respectively. Dispositional empathy was evaluated through the Interpersonal Reactivity Index, which consists of four subscales: Perspective Taking, Fantasy, Empathic Concern, and Personal Distress. Hierarchial linear regression analyses were performed to identify the variables related to PTSR and GPD. High PTSR was significantly associated with high Fantasy (identification tendency, β = 0.21, p < .01), high Personal Distress (the self-oriented emotional disposition of empathy, β = 0.18, p < .05), and no experience of disaster relief activities (β = 0.15, p < .05). High GPD was associated with high Personal Distress (β = 0.28, p < .001), marital status (married, β = 0.22, p < .01), being female (β = 0.18, p < .01), medical unit (β = 0.18, p < .05), and no experience of disaster relief activities (β = 0.13, p < .05). Among Japanese uniformed disaster workers, high PTSR was associated with two subtypes of dispositional empathy: the self-oriented emotional disposition of empathy and high identification tendency, whereas high GPD was associated with high identification tendency. Educational interventions that aim to mitigate these tendencies might be able to relieve the psychological distress of disaster workers.

Background: In many developed countries, mood disorders have become problematic, and the economic loss due to treatment costs and interference with work is immeasurable. Therefore, a simple technique to determine individuals’ depressive state and stress level is desired. Methods: We developed a method to assess specific the psychological issues of individuals with major depressive disorders using emotional components contained in their voice. We propose two indices: vitality, a short-term index, and mental activity, a long-term index capturing trends in vitality. To evaluate our method, we used the voices of healthy individuals (n = 14) and patients with major depression (n = 30). The patients were also assessed by specialists using the Hamilton Rating Scale for Depression (HAM-D). Results: A significant negative correlation existed between the vitality extracted from the voices and HAM-D scores (r = −0.33, p < 0.05). Furthermore, we could discriminate the voice data of healthy individuals and patients with depression with a high accuracy using the vitality indicator (p = 0.0085, area under the curve of the receiver operating characteristic curve = 0.76).

Previously our study has shown that the DNA methylation (DNAm) levels at CpG sites in the pro-inflammatory cytokine gene, TNF-alpha, decrease along with aging, suggesting the potential role of DNAm in aging and heightened inflammatory process leading to increased risk for delirium. However, DNAm differences between delirium cases and non-delirium controls have not been investigated directly. Therefore, we examined genome-wide DNAm differences in blood between patients with delirium and controls to identify useful epigenetic biomarkers for delirium. Data from a total of 87 subjects (43 delirium cases) were analyzed by a genome-wide DNAm case-control association study. A genome-wide significant CpG site near the gene of LDLRAD4 was identified (p = 5.07E-8). In addition, over-representation analysis showed several significant pathways with a false discovery rate adjusted p-value < 0.05. The top pathway with a Gene Ontology term was immune response, and the second top pathway with a Kyoto Encyclopedia of Genes and Genomes term was cholinergic synapse. Significant DNAm differences related to immune/inflammatory response were shown both at gene and pathway levels between patients with delirium and non-delirium controls. This finding indicates that DNAm status in blood has the potential to be used as epigenetic biomarkers for delirium.

We previously reported the association between DNA methylation (DNAm) of pro-inflammatory cytokine genes and age. In addition, neurotrophic factors are known to be associated with age and neurocognitive disorders. Therefore, we hypothesized that DNAm of neurotrophic genes change with age, especially in delirium patients. DNAm was analyzed using the Illumina HumanMethylation450 or HumanMethylationEPIC BeadChip Kit in 3 independent cohorts: blood from 383 Grady Trauma Project subjects, brain from 21 neurosurgery patients, and blood from 87 inpatients with and without delirium. Both blood and brain samples showed that most of the DNAm of neurotrophic genes were positively correlated with age. Furthermore, DNAm of neurotrophic genes was more positively correlated with age in delirium cases than in non-delirium controls. These findings support our hypothesis that the neurotrophic genes may be epigenetically modulated with age, and this process may be contributing to the pathophysiology of delirium.