Health anxiety (HA), defined as excessive worry about having a serious medical condition, may affect preventive behaviors during the coronavirus disease 2019 (COVID-19) pandemic. We examined the distinct role of two dimensions of HA-perceived likelihood (probability dimension) and awfulness of illness (awfulness dimension)-in self-protection, as reflected in preventive behaviors during the pandemic. Participants comprised 657 healthcare workers. Data were collected between February 24 and 26, 2021. The Short Health Anxiety Inventory determined the HA dimensions. Adherence to the government's recommendations for COVID-19 preventive behaviors was self-rated. An independent association between each HA dimension and participants' adherence to the recommendations was examined using multivariable regression. Within the analyzed sample of 560 subjects, severe HA was observed in 9.1 %. The more the participants felt awful, the less frequently they engaged in the recommended preventive behaviors (adjusted odds ratio = 0.993, 95 % confidence interval: 0.989, 0.998, p = 0.003) regardless of their profession, working position, psychological distress, sleep disturbance, and current physical diseases. However, the probability dimension was not associated with their preventive behaviors. The awfulness dimension of HA could be a more sensitive marker of preventive behaviors than the probability dimension. Paying particular attention to the awfulness dimension may help optimize self-protection strategies during the COVID-19 pandemic. A two-dimensional understanding of HA may be useful for the maintenance of the healthcare system and public health as well as healthcare workers' own health.

Purpose: Decreased delta and increased alpha wave activity during sleep may be specific pathophysiological features of major depressive disorder; however, their usefulness as biomarkers remains unclear. We examined the use of mean alpha and delta wave power value indices during sleep to identify major depressive disorder using a portable electroencephalography device. Methods: We compared the mean alpha and delta wave power value indices of six unmedicated patients with major depressive disorder and seven age- and sex-matched healthy controls using a portable electroencephalography device in this case-controlled study. Results: The ratio of the mean alpha power values for the non-rapid and rapid eye movement periods was significantly lower in the major depressive disorder group (1.3 ± 0.2) than in the healthy group (2.3 ± 0.6; P = 0.004). The ratio of the mean delta power values for the non-rapid eye movement and rapid eye movement periods did not differ between groups but negatively correlated significantly with the Hamilton Rating Scale for Depression score (r = -0.784, P = 0.002). The area under the receiver operating characteristic curve (95% confidence interval) of the mean alpha power ratio for non-rapid eye movement and rapid eye movement periods for distinguishing the two groups was 0.93 (0.78–1.00), and both sensitivity and specificity exceeded 85% at a cut-off value ≤ 1.71. Conclusion: The alpha- and delta-related power value indices may capture different aspects of major depressive disorder pathology.

Evidence provides support for the therapeutic benefits of targeting avoidance in prolonged grief. However, it is not clear whether avoidance interferes with mourning through altered resilience to stress, as measured by heart rate variability (HRV). Thirty-five adults (30 female; mean age: 39.2 years), who had been bereaved for more than one year, participated in this prospective, observational study. At each of the initial assessments and up to six-month follow-ups, grief symptoms were assessed using the Complicated Grief Questionnaire, and a resting electrocardiogram was recorded to extract the high-frequency component of HRV (HF-HRV). To differentiate avoidance from grief itself, principal component analysis was used. A nonlinear cross-sectional relationship was observed between avoidance and HF-HRV (coefficient = 0.29, p = .003); the lower the avoidance, the lower the HF-HRV in the low avoidance group. Grief improved only in the low avoidance group longitudinally. The observed relationship between increased HF-HRV and decreased grief was modified by the avoidance group, such that the low-avoidance group drove this association (estimate -0.53, 95% CI -0.86, -0.21, p = .001), while the high-avoidance group did not (estimate 0.44, 95% CI -0.32, 1.20, p = .26). Despite its palliative gain, avoidance relates to the maintenance of grief longitudinally through attenuated autonomic resilience to stress.

Background/Objectives: Non-restorative sleep (NRS)—a subjective feeling of unrefreshing/insufficient rest despite adequate sleep duration—an important sleep-quality indicator is associated with depression and mortality. We examined whether insoluble dietary fiber intake is associated with NRS in Japanese adults, after adjusting for socioeconomic, lifestyle, and dietary factors. Methods: Using cross-sectional data from 5034 adult (≥20 years) respondents of the National Health and Nutrition Surveys (2014 and 2018), Japan, self-assessed NRS (coded as 1, absence as 0) was analyzed with insoluble fiber intake (g/1000 kcal) modeled as a continuous variable; logistic regression analyses with progressive adjustments included Model 1, adjusted for sex, age, and body mass index; Model 2, comprising socioeconomic and lifestyle factors; Model 3, adjusted for sleep duration; and Model 4, which included dietary energy, protein, fat, vitamin D, and magnesium. Results: Among 19.3% of participants with NRS, the median (interquartile range) insoluble dietary fiber intake was 5.45 (4.10–6.97) g/1000 kcal, with higher NRS prevalence among younger adults (<60 years), non-drinkers (no habitual alcohol consumption), and individuals with short sleep (<6 h). Higher insoluble dietary fiber intake was consistently associated with a lower NRS likelihood, before and after adjustment for potential confounders. In the fully adjusted model, younger age (<60 years), no habitual alcohol consumption, and short sleep (<6 h) were independently associated with greater odds of NRS. Conclusions: Higher insoluble dietary fiber density correlated with lower odds of NRS, indicating a significant association, rather than causation, that warrants longitudinal clarification of the temporal relationship between dietary fiber intake and perceived sleep restorativeness.

Background: Melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGC) contribute predominantly to non-image-forming effects of light, such as light-induced circadian phase shift, melatonin suppression, and pupillary light reflex. Post-illumination pupil response (PIPR) has been well-used for the evaluation of ipRGC sensitivity for humans since it is able to detect ipRGC function independently from conventional cones. However, pharmacological mydriasis or a specialized light stimulation system, such as the Maxwellian view (MV) optical system, is required to avoid dynamic pupil constriction in the stimulated eye for effective PIPR measurements, which makes these approaches less practical and difficult to implement in standard experimental settings. In this context, we propose the application of a retinal projection viewfinder based on the MV system as a practical approach for measuring PIPR, and evaluate the feasibility of this approach by comparing its performance with a typical LED-based optical system. Methods: Twenty-two healthy participants underwent pupillometry using both the MV-based viewfinder and a typical LED-based system. Monochromatic red and blue light stimuli were presented for durations of 1 and 10 seconds. Pupil responses, including maximum constriction, PIPR amplitude after 6 seconds from the light offset, area under the curve (AUC) values of PIPR, and sustained slopes, were analyzed using a linear mixed-effects model to assess the differences between the two systems. Results: The MV-based viewfinder significantly enhanced net PIPR amplitude ( p < 0.05) and sustained slope ( p < 0.01) during 10-second light stimulation compared to the LED system, demonstrating its capability to effectively measure ipRGC-driven responses. In contrast, no significant differences were observed in the net AUC values. These results highlight that the MV-based viewfinder enables effective PIPR measurements by delivering constant and controlled light stimulation directly to the retina, minimizing the effects of dynamic pupil constriction during light stimulation. Conclusions: The MV-based viewfinder showed feasibility as an effective method for measuring PIPR without requiring pharmacological dilation or complex optical instrumentation. This approach has strong potential for advancing the assessment of human ipRGC function using pupillary responses.