Psychosocial Stress and Hypothalamic-Pituitary-Adrenal Axis Stress Reactivity: Variations by Race and Socioeconomic Status Among Adults at Risk of Diabetes

Gut microbiota connects the brain and the heart: potential mechanisms and clinical implications

Nowadays, high morbidity and mortality of cardiovascular diseases (CVDs) and high comorbidity rate of neuropsychiatric disorders contribute to global burden of health and economics. Consequently, a discipline concerning abnormal connections between the brain and the heart and the resulting disease states, known as psychocardiology, has garnered interest among researchers. However, identifying a common pathway that physicians can modulate remains a challenge. Gut microbiota, a constituent part of the human intestinal ecosystem, is likely involved in mutual mechanism CVDs and neuropsychiatric disorder share, which could be a potential target of interventions in psychocardiology. This review aimed to discuss complex interactions from the perspectives of microbial and intestinal dysfunction, behavioral factors, and pathophysiological changes and to present possible approaches to regulating gut microbiota, both of which are future directions in psychocardiology.

Lifetime Interpersonal Violence or Abuse and Diabetes Rates by Sex and Race

INTRODUCTION

Lifetime exposure to interpersonal violence or abuse has been associated with several chronic diseases, including adult-onset diabetes, yet this pattern has not been confirmed by sex and race within a large cohort.

METHODS

Data from the Southern Community Cohort Study collected between 2002-2009 and 2012-2015 were used to explore the relationship between lifetime interpersonal violence or abuse and diabetes (N=25,251). Prospective analyses of lower-income people living in the southeastern U.S. were conducted in 2022 to examine the risk of adult-onset diabetes associated with lifetime interpersonal violence or abuse by sex and race. Lifetime interpersonal violence or abuse was defined as (1) physical or psychological violence, threats, or abuse in adulthood (adult interpersonal violence or abuse) and (2) childhood abuse or neglect.

RESULTS

After adjustment for potentially confounding factors, adult interpersonal violence or abuse was associated with a 23% increased risk of diabetes (adjusted hazard ratio=1.23; 95% CI=1.16, 1.30). Diabetes risks associated with childhood abuse or neglect were 15% (95% CI=1.02, 1.30) for neglect and 26% (95% CI=1.19, 1.35) for abuse. When combining adult interpersonal violence or abuse and childhood abuse or neglect, the risk of diabetes was 35% higher (adjusted hazard ratio=1.35; 95% CI=1.26, 1.45) than those experiencing no violence, abuse, or neglect. This pattern held among Black and White participants, and among women and men.

CONCLUSIONS

Both adult interpersonal violence or abuse and childhood abuse or neglect increased the risk of adult-onset diabetes in a dose-dependent pattern for men and women, and by race. Intervention and prevention efforts to reduce adult interpersonal violence or abuse and childhood abuse or neglect could not only reduce the risk of lifetime interpersonal violence or abuse but may also reduce one of the most prevalent chronic diseases, adult-onset diabetes.

Leveraging a genetically-informative study design to explore depression as a risk factor for type 2 diabetes: Rationale and participant characteristics of the Mood and Immune Regulation in Twins Study

Background

Comorbidity between depression and type 2 diabetes is thought to arise from the joint effects of psychological, behavioral, and biological processes. Studies of monozygotic twins may provide a unique opportunity for clarifying how these processes inter-relate. This paper describes the rationale, characteristics, and initial findings of a longitudinal co-twin study aimed at examining the biopsychosocial mechanisms linking depression and risk of diabetes in mid-life.

Methods

Participants in the Mood and Immune Regulation in Twins (MIRT) Study were recruited from the Mid-Atlantic Twin Registry. MIRT consisted of 94 individuals who do not have diabetes at baseline, representing 43 twin pairs (41 monozygotic and 2 dizygotic), one set of monozygotic triplets, and 5 individuals whose co-twin did not participate. A broad set of variables were assessed including psychological factors (e.g., lifetime history major depression (MD)); social factors (e.g., stress perceptions and experiences); and biological factors, including indicators of metabolic risk (e.g., BMI, blood pressure (BP), HbA1c) and immune functioning (e.g., pro- and anti-inflammatory cytokines), as well as collection of RNA. Participants were re-assessed 6-month later. Intra-class correlation coefficients (ICC) and descriptive comparisons were used to explore variation in these psychological, social, and biological factors across time and within pairs.

Results

Mean age was 53 years, 68% were female, and 77% identified as white. One-third had a history of MD, and 18 sibling sets were discordant for MD. MD was associated with higher systolic (139.1 vs 132.2 mmHg, p=0.05) and diastolic BP (87.2 vs. 80.8 mmHg, p=0.002) and IL-6 (1.47 vs. 0.93 pg/mL, p=0.001). MD was not associated with BMI, HbA1c, or other immune markers. While the biological characteristics of the co-twins were significantly correlated, all within-person ICCs were higher than the within-pair correlations (e.g., HbA1c within-person ICC=0.88 vs. within-pair ICC=0.49; IL-6 within-person ICC=0.64 vs. within-pair=0.54). Among the pairs discordant for MD, depression was not substantially associated with metabolic or immune markers, but was positively associated with stress.

Conclusions

Twin studies have the potential to clarify the biopsychosocial processes linking depression and diabetes, and recently completed processing of RNA samples from MIRT permits future exploration of gene expression as a potential mechanism.