Social stress and psychiatric disorders: Evolutionary reflections on debated questions

An analysis of POMC gene methylation and expression in patients with schizophrenia

Schizophrenia is a chronic mental disorder that affects millions of people and is believed to be caused by both environmental and genetic factors. Despite extensive research, the exact mechanisms underlying schizophrenia are still unclear. Studies have shown that numerous psychiatric disorders are associated with methylation of the POMC gene, which encodes adrenocorticotropic hormone, a critical player in the hypothalamic-pituitary-adrenal axis. However, the association between DNA methylation in POMC patients and schizophrenia remains unclear. In this study, we evaluated three fragments of the POMC promoter region, including 51 CpG sites, in the peripheral blood of schizophrenia patients and healthy controls. The POMC protein level was measured via enzyme-linked immunosorbent assay (ELISA). The schizophrenia group exhibited significantly greater levels of methylation of the POMC gene than those in the control group. The methylation level of the POMC-2 fragment was significantly greater in the patient group than in the control group. There were 17 significantly hypermethylated CpG sites in the patient group. After stratification by sex, POMC methylation levels were found to be significantly greater in male schizophrenia patients than in healthy controls; the methylation levels of POMC-2 fragments were greater in the male patient group; nine CpG sites were significantly hypermethylated in the male patient group; and only one CpG site was significantly hypermethylated in the female patient group. The POMC protein level in patients was significantly lower than that in healthy controls. These findings demonstrate that the DNA methylation of POMC might be associated with the pathophysiology of schizophrenia. Overall, studying the correlation between POMC methylation and schizophrenia may contribute to the diagnosis and evaluation of neuropsychiatric disorders.

An evolutionary analysis of the applicability and utility of the clinico-pathological method in psychiatry

Unlike other medical specialties, psychiatry has not been involved in the theoretical shift that replaced the syndromal approach with the clinico-pathological method, which consists in explaining clinical manifestations by reference to morbid anatomical and physiological changes. Past and present discussions on the applicability of the clinico-pathological method in psychiatry are based on a pre-Darwinian concept of biology as the study of proximate causation. Distinguishing between mediating mechanisms and evolved functions, an evolutionary perspective offers an original contribution to the debate by overcoming the opposite views of dualism (i.e., the clinico-pathological method is not applicable to disorders of the mind) and neuroessentialism (i.e., the definitive way of explaining psychiatric disorders is by reference to the brain and its activity). An evolutionary perspective offers original insights on the utility of the clinico-pathological method to solve critical questions of psychiatric research and clinical practice, including the distinction between mental health and illness, a better understanding of the etiology and pathophysiology, the classification and differential diagnosis of psychiatric disorders, and the development of more efficacious psychiatric treatments.

Modifiable lifestyle factors influencing psychiatric disorders mediated by plasma proteins: A systemic Mendelian randomization study

BACKGROUND

Psychiatric disorders are emerging as a serious public health hazard, influencing an increasing number of individuals worldwide. However, the effect of modifiable lifestyle factors on psychiatric disorders remains unclear.

METHODS

Genome-wide association studies (GWAS) summary statistics were obtained mainly from Psychiatric Genomics Consortium and UK Biobank, with sample sizes varying between 10,000 and 1,200,000. The two-sample Mendelian randomization (MR) method was applied to investigate the causal associations between 45 lifestyle factors and 13 psychiatric disorders, and screen potential mediator proteins from 2992 candidate plasma proteins. We implemented a four-step framework with step-by-step screening incorporating two-step, univariable, and multivariable MR.

RESULTS

We found causal effects of strenuous sports or other exercise on Tourette's syndrome (OR [95%CI]: 0.0047 [5.24E-04-0.042]); lifelong smoking index on attention-deficit hyperactivity disorder (10.53 [6.96-15.93]), anxiety disorders (3.44 [1.95-6.05]), bipolar disorder (BD) (2.25 [1.64-3.09]), BD II (2.89 [1.81-4.62]), and major depressive disorder (MDD) (2.47 [1.90-3.20]); and educational years on anorexia nervosa (AN) (1.47 [1.22-1.76]), and MDD (0.74 [0.66-0.83]). Five proteins were found to have causal associations with psychiatric disorders, namely ADH1B, GHDC, STOM, CD226, and TP63. STOM, a membrane protein deficient in the erythrocytes of hereditary stomatocytosis patients, may mediate the effect of educational attainment on AN.

LIMITATIONS

The mechanisms underlying the effects of lifestyle factors on psychiatric disorders require further investigation.

CONCLUSIONS

These findings could help assess the risk of psychiatric disorders based on lifestyle factors and also support lifestyle interventions as a prevention strategy for mental illness.

The dynamic changes of psychosomatic symptoms in three waves of COVID-19 outbreak and fatigue caused by enduring pandemic in China

BACKGROUND

Two years have passed since the 2019 novel coronavirus disease (COVID-19) was first reported. The persistent pandemic might lead to severe psychosomatic problems and fatigue. In addition, the recent rapid rising COVID-19 cases in China have become a trending issue. Therefore, this study aimed to investigate the dynamic changes in psychosomatic problems at the initial and current stages of the pandemic.

METHODS

Three waves of cross-sectional online survey were conducted during the initial COVID outbreak in China. The psychosomatic symptom scale (PSSS), perceived stress scale (PSS), and pandemic fatigue scale (PFS) were used to assess the psychosomatic problems, stress, and fatigue.

RESULTS

4317, 1096, and 2172 participants completed the first, second, and third surveys. The prevalence of psychosomatic disorder was 22 %, 28 %, and 39 %, respectively. The network structure of PSSS symptoms has not significantly changed as the pandemic progresses. However, the global strength of the PSSS networks, indicating the overall connectivity, in the third wave was significantly higher than in the first wave (s = 0.54, P = 0.007). The most central symptoms in the first and third wave networks were depressed mood and tiredness. The PFS score was higher in the people concerned with indirect impact than those concerned with health (P < 0.001). PFS has positive relationships with PSSS and PSS score (R = 0.41, P < 0.001 and R = 0.35, P < 0.001, respectively).

CONCLUSIONS

The persistence of the pandemic caused critical psychosomatic issues, stress, and indirect burden over time, leading to inevitable fatigue. People endured needing immediate attention to prevent or reduce psychosomatic disorders.

Mental Health Challenges during the COVID-19 Pandemic

The impact of the COVID-19 pandemic on mental health has unveiled the complexity of the relationship between psychiatry and the rest of medicine, as clearly shown by the collection of studies published in this Special Issue entitled "Mental Health Challenges during the COVID-19 Pandemic" [...].

Social Construction and Evolutionary Perspectives on Gender Differences in Post-traumatic Distress: The Case of Status Loss Events

Women report greater post-traumatic distress (PTD) than men following physically threatening events. However, gender differences in PTD following social stressors such as status losses are understudied. Whereas the social construction account points to a general sensitivity in women following any type of stressor, the evolutionary account suggests enhanced sensitivity to status losses in men, especially following inter-males aggressions. These propositions were examined in two studies (Study 1, N = 211; Study 2, N = 436). Participants were asked to recall a status loss and to fill out measures assessing PTD and depression severity. In line with the evolutionary account, men, as compared to women, displayed enhanced PTD following status loss. Status losses conducted by men against men were associated with greater PTD than were instances involving other target-aggressor pairings. Finally, age was negatively associated with PTD in men but not in women. The examination of evolutionary challenges modifies the standard view linking the female gender to enhanced sensitivity to trauma. Thus, the pattern of enhanced sensitivity to stressful events appears to be affected by gender- and development-specific adaptive challenges.

Integrating Evolutionary, Cultural, and Computational Psychiatry: A Multilevel Systemic Approach

This paper proposes an integrative perspective on evolutionary, cultural and computational approaches to psychiatry. These three approaches attempt to frame mental disorders as multiscale entities and offer modes of explanations and modeling strategies that can inform clinical practice. Although each of these perspectives involves systemic thinking, each is limited in its ability to address the complex developmental trajectories and larger social systemic interactions that lead to mental disorders. Inspired by computational modeling in theoretical biology, this paper aims to integrate the modes of explanation offered by evolutionary, cultural and computational psychiatry in a multilevel systemic perspective. We apply the resulting Evolutionary, Cultural and Computational (ECC) model to Major Depressive Disorder (MDD) to illustrate how this integrative approach can guide research and practice in psychiatry.

Perceived social support in the social distancing era: the association between circles of potential support and COVID-19 reactive psychopathology

BACKGROUND AND OBJECTIVES

Stressors related to the COVID-19 pandemic are risk factors for psychopathology, but psychosocial protective factors might play a crucial role in buffering the pathogenic effects of the outbreak.

DESIGN

In the current study, we examined the association of inner resources and potential external sources of support for coping with the pandemic and related lockdowns to mental health during the pandemic, while controlling for sociodemographic variables as covariates.

METHODS

We tested the model in a probability-based internet survey of a representative sample of the Israeli adult population (N = 812) conducted during the COVID-19 pandemic.

RESULTS

Perceived support in close relationships was negatively associated with the intensity of depression, anxiety, obsessive-compulsive disorder (OCD) and post-traumatic stress disorder (PTSD). Larger rings of potential support such as perceived belongingness to a community and trust in government were also negatively related to anxiety and depression but were positively associated with the intensity of OCD and PTSD.

CONCLUSIONS

Findings support the "tend and befriend" theory in the social distancing era and highlight the importance of keeping personal relationships alive when facing a mass trauma.

Borderline Personality Disorder in a "Life History Theory" Perspective: Evidence for a Fast "Pace-of-Life-Syndrome"

"Borderline Personality Disorder" (BPD) is associated with heightened risk for cardiovascular disease and other stress-associated somatic consequences, which is poorly understood in terms of causal mechanisms, such as childhood trauma. Here, we tested the hypothesis suggesting that BPD reflects a fast "Pace-of-Life-Syndrome" (PoLS). Ninety-five women (44 diagnosed with BPD) were recruited to examine psychological correlates of PoLS, including life history features, personality dimensions, aggressiveness, chronic stress, borderline symptom severity, childhood trauma, and allostatic load (AL). In line with expectations, BPD patients had significantly higher scores suggestive of a fast PoLS than controls, they were more aggressive, more burdened with chronic stress and were exposed to more severe childhood adversity. Childhood trauma predicted PoLS, which in turn predicted AL. The present study thus provides direct evidence of psychological and somatic traits associated with the fast end of the PoLS spectrum in females with BPD. Findings are discussed with regard to clinical implications.