The gut–brain axis plays a role in major depressive disorder (MDD). Gut-bacterial metabolites are suspected to reduce low-grade inflammation and influence brain function. Nevertheless, randomized, placebo-controlled probiotic intervention studies investigating metabolomic changes in patients with MDD are scarce. The PROVIT study (registered at clinicaltrials.com NCT03300440) aims to close this scientific gap. PROVIT was conducted as a randomized, single-center, double-blind, placebo-controlled multispecies probiotic intervention study in individuals with MDD (n = 57). In addition to clinical assessments, metabolomics analyses (1H Nuclear Magnetic Resonance Spectroscopy) of stool and serum, and microbiome analyses (16S rRNA sequencing) were performed. After 4 weeks of probiotic add-on therapy, no significant changes in serum samples were observed, whereas the probiotic groups’ (n = 28) stool metabolome shifted towards significantly higher concentrations of butyrate, alanine, valine, isoleucine, sarcosine, methylamine, and lysine. Gallic acid was significantly decreased in the probiotic group. In contrast, and as expected, no significant changes resulted in the stool metabolome of the placebo group. Strong correlations between bacterial species and significantly altered stool metabolites were obtained. In summary, the treatment with multispecies probiotics affects the stool metabolomic profile in patients with MDD, which sets the foundation for further elucidation of the mechanistic impact of probiotics on depression.

The COVID-19 pandemic affects both mentally healthy and ill individuals. Individuals with bipolar disorder (BD) constitute an especially vulnerable group. A multicentric online study was conducted in Austria, Denmark, and Germany after the first lockdown phase in 2020. In total, 117 healthy controls (HC) were matched according to age and sex to 117 individuals with BD. The survey included the Brief Symptom Inventory-18, Beck Depression Inventory-2, Pittsburgh Sleep Quality Index, and a self-constructed questionnaire assessing COVID-19 fears, emotional distress due to social distancing, lifestyle, and compliance to governmental measures. In individuals with BD, increased symptoms of depression, somatization, anxiety, distress due to social distancing, and poorer sleep quality were related to emotional distress due to social distancing. The correlation between emotional distress due to social distancing and anxiety showed 26% of shared variance in BD and 11% in HC. Negative lifestyle changes and lower compliance with COVID-19 regulatory measures were more likely to be observed in individuals with BD than in HC. These findings underscore the need for ongoing mental health support during the pandemic. Individuals with BD should be continuously supported during periods of social distancing to maintain a stable lifestyle and employ strategies to cope with COVID-19 fears.

Bipolar disorder (BD) is associated with impairments in cognitive functions, in which metabolic factors, e.g., overweight, seem to play a significant role. The aim of this study was to investigate the association between nutritional factors and cognitive performance in euthymic individuals with BD. A study cohort of 56 euthymic individuals with BD was compared to a sample of 53 mentally healthy controls. To assess cognitive function, the following tests were applied: California Verbal Learning Test, Trail Making Test A/B, d2 Test of Attention-Revised, and Stroop’s Color-Word Interference Test. Furthermore, a 4-day food record was processed to evaluate dietary intake of macronutrients, specific micronutrients, and food diversity. Body mass index and waist to height ratio were calculated to assess overweight and central obesity. Results showed no nutritional differences between individuals with BD and controls. Individuals with BD performed worse in the d2 test than controls. Hierarchical regression analyses yielded no association between cognitive and nutritional parameters. However, waist to height ratio was negatively correlated with almost all cognitive tests. Central obesity seems to affect cognitive functioning in BD, while the lack of finding differences in nutritional data might be due to problems when collecting data and the small sample size. Consequently, further studies focusing on objectively measuring food intake with adequate sample size are needed.

The global spread of the coronavirus disease (COVID-19) has created new challenges for the entire healthcare system, and those who work directly with the patients or even on the front lines with COVID-19 patients have been particularly stressed. Only a few studies are currently available investigating psychosomatic symptoms among healthcare workers, particularly frontline workers, over the entire pandemic period (2020–2022). There is also a lack of knowledge about strategies to prevent stress during and after a health crisis. Methods: An online survey was conducted at three times (April 2020, winter 2020/2021, and winter 2021/2022) during the COVID-19 pandemic in Austria. The sample included 160 healthcare workers at screening time 1, 1.361 healthcare workers at screening time 2, and 1.134 healthcare workers at screening time 3. The survey included COVID-19 work-related fears, satisfaction with the frontline work, and standardized inventories to assess psychosomatic symptoms, such as the Patient Health Questionnaire (PHQ-D). Results: Psychosomatic symptoms were more common among women compared to men, and among frontline workers compared to non-frontline workers, especially during the course of the pandemic at t2 and t3. Self-reported scores of COVID-19 work-related fears were significantly associated with psychosomatic symptoms. Furthermore, in frontline workers, there was a significant association between the feeling of being safe and well-informed and psychosomatic symptoms. Conclusion: COVID-19 work-related fears and psychosomatic symptoms have been prevalent among healthcare workers throughout the pandemic. Feeling safe and informed appears to be essential to prevent psychosomatic symptoms, leading to a recommendation for employers in the healthcare sector to focus on communication and information. As frontline workers are especially prone to psychosomatic symptoms, more stress prevention programs for them will be essential to maintain productivity and reduce sick days and fluctuations in the healthcare system.

Background: Due to the COVID-19 pandemic, workplaces in the medical field experienced changes. Non-frontline workers in the health sector (WHS) were in many cases allowed to work from home (WFH). Changes in work locations have affected the perception of productivity during the COVID-19 pandemic compared to the pre-pandemic perception. Studies regarding this research field are rare for WHS. The aim of the present study was to investigate the perception of productivity and its impact on symptoms of depression during the COVID-19 pandemic. The second objective was to assess the implications for post-pandemic work settings such as WFH or work scenarios in hospitals during pandemics. Methods: At three points in time during the COVID-19 pandemic (t1; n = 161: April 2020, t2; n = 1598 winter 2020/2021, t3; n = 1879 winter 2021/2022), an online survey of WHS (e.g., medical doctors, nurses, scientific staff) in Austria concerning their productivity in their current workplace (pre- and post-pandemic) was conducted. The online survey included questions about the perceptions of productivity changes (i.e., perceptions of lower, equal, and higher productivity, before and during the COVID-19 pandemic) in different work settings (e.g., working in a hospital or working from home), as well as standardized questionnaires like the Patient Health Questionnaire (PHQ-9), assessing symptoms of depression in WHS. Results: χ² tests showed that WHS working in hospitals experienced significantly fewer fluctuations in their perceptions of productivity than WHS working from home. An analysis of variance (ANOVA) indicated that WHS with a lower perception of productivity tended to have higher self-assessed depressive symptoms. Conclusion: The possibility of remaining working in the hospital in stressful scenarios like the COVID-19 pandemic might stabilize the feeling of productivity. Moreover, productivity is associated with self-assessed depressive symptoms. Hence, looking into the reasons behind this discrepancy between WHS in hospitals and those working from home might help to improve the home office modality and to create better structures, which are related to symptoms of depression.

The connection between cognitive function and the “Big Five” personality traits (openness, conscientiousness, extraversion, agreeableness, and neuroticism) in the general population is well known; however, studies researching bipolar disorder (BD) are scarce. Therefore, this study aimed to investigate the Big Five as predictors of executive function, verbal memory, attention, and processing speed in euthymic individuals with BD (cross-sectional: n = 129, including time point t1; longitudinal: n = 35, including t1 and t2). Participants completed the NEO Five-Factor Inventory, the Color and Word Interference Test, the Trail Making Test, the d2 Test of Attention Revised, and the California Verbal Learning Test. The results showed a significant negative correlation between executive function and neuroticism at t1. Changes in cognitive function between t1 and t2 did not correlate with and could not be predicted by the Big Five at t1. Additionally, worse executive function at t2 was predicted by higher neuroticism and lower conscientiousness at t1, and high neuroticism was a predictor of worse verbal memory at t2. The Big Five might not strongly impact cognitive function over short periods; however, they are significant predictors of cognitive function. Future studies should include a higher number of participants and more time in between points of measurement.