Associations between APOE Variants and Metabolic Traits and the Impact of Psychological Stress

In a previous study, we observed that associations between APOE rs439401 and metabolic traits were moderated by chronic stress. Thus, in a population of stressed and non-stressed Danish men, we examined whether associations between APOE rs439401 and a panel of metabolic quantitative traits, all metabolic traits which may lead to T2D and CVD were moderated by psychological stress.Obese young men (n = 475, BMI ≥ 31.0 kg/m(2)) and a randomly selected control group (n = 709) identified from a population of 141,800 men were re-examined in two surveys (S-46: mean age 46, S-49: mean age 49 years) where anthropometric and biochemical measures were available. Psychological stress factors were assessed by a self-administered 7-item questionnaire. Each item had the possible response categories "yes" and "no" and assessed familial problems and conflicts. Summing positive responses constituted a stress item score, which was then dichotomized into stressed and non-stressed. Logistic regression analysis, applying a recessive genetic model, was used to assess odds ratios (OR) of the associations between APOE rs439401 genotypes and adverse levels of metabolic traits.The APOE rs439401 TT-genotype associated positively with BMI (OR = 1.09 [1.01; 1.17]), waist circumference (OR = 1.09 [1.02; 1.17]) in stressed men at S-46. Positive associations were observed for fasting plasma glucose (OR = 1.42 [1.07; 1.87]), serum triglycerides (OR = 1.41 [1.05; 1.91]) and with fasting plasma insulin (OR = 1.48 [1.05; 2.08]) in stressed men at S-49. Rs439401 TT-genotype also associated positively with surrogate measures of insulin resistance (HOMA-IR; OR = 1.21 [1.03; 1.41]) and inversely with insulin sensitivity (Stumvoll index; OR = 0.90 [0.82; 0.99], BIGTT-S(I); OR = 0.60 [0.43; 0.85]) in stressed men. No significant associations were observed in non-stressed men, albeit the estimates showed similar but weaker trends as in stressed men.The present results suggest that the APOE rs439401 TT-genotype is associated with an adverse metabolic profile in a population of psychologically stressed Danish men

Nonequilibrium phase transition due to social group isolation

We introduce a simple model of a growing system with $m$ competing communities. The model corresponds to the phenomenon of defeats suffered by social groups living in isolation. A nonequilibrium phase transition is observed when at critical time $t_c$ the first isolated cluster occurs. In the one-dimensional system the volume of the new phase, i.e. the number of the isolated individuals, increases with time as $Z \sim t^3$. For a large number of possible communities the critical density of filled space equals to $\rho_c = (m/N)^{1/3}$ where $N$ is the system size. A similar transition is observed for Erd\H{o}s-R\'{e}nyi random graphs and Barab\'{a}si-Albert scale-free networks. Analytic results are in agreement with numerical simulations.Comment: 5 pages, 4 figure

Systolic Blood Pressure, Socioeconomic Status, and Biobehavioral Risk Factors in a Nationally Representative US Young Adult Sample

In the National Longitudinal Study of Adolescent Health, a US longitudinal study of over 15,000 young adults, we examined the extent to which socioeconomic status is linked to systolic blood pressure, and whether biobehavioral risk factors mediate the association. Over 62% of the participants had systolic blood pressure >120 mmHg and 12% with systolic blood pressure >140 mmHg. Over 66% were classified as at least overweight (Body Mass Index>25 kg/m2), with over 36% meeting criteria for at least Class I obesity (Body Mass Index>30 kg/m2). Multivariate models showed that higher household income and being married were independently associated with lower systolic blood pressure. Higher body mass index, greater waist circumference, smoking, and higher alcohol intake were each independently associated with higher systolic blood pressure. Meditational analyses suggested that higher education level was associated with lower systolic blood pressure by way of lower body mass, smaller waist circumference, and lower resting heart rate. When these indirect effects were accounted for, education was not significantly associated with systolic blood pressure. In contrast, household income remained associated with systolic blood pressure even with control for all covariates. Results reinforce current public health concerns about rates of obesity and high blood pressure among young adults and suggest that disparities in education level and household income may play an important role the observed decrements in health. Identifying modifiable mechanisms that link socioeconomic status to systolic blood pressure using data from a large representative sample may improve risk stratification and guide the development of effective interventions

Associations of Social Support and 8-Year Follow-Up Depressive Symptoms: Differences in African American and White Caregivers

The present study used data from the Alzheimer’s Study of Emotions in Caregivers (ASEC) to evaluate perceptions of social support assessed at baseline, as well as changes in social support assessed at a follow-up eight-years later, as predictors of symptoms of change in depression, with a focus on race as a potential moderator of these relationships. Specifically, multiple regression analyses adjusted for age, sex, income, education, race, living arrangement of care recipient at baseline, death of care recipient, the cultural justification for caregiving scale (CJCS), and baseline depressive symptoms were conducted to assess baseline social support ratings, as well as the change in social support over time as a predictor of depression at follow-up—with a focus on moderation by race. Baseline social support (F(1,77) = 7.60, p=.008) was associated with fewer depressive symptoms at follow-up for all participants. The change in social support over time was also related to depressive symptoms, with effects moderated by race (F(1,77) = 7.97, p = .007), such that when support decreased over time depressive symptoms at follow-up were higher for Whites, as compared with African Americans, whereas, when social support increased over time depressive symptoms tended to be similar for both groups. These findings indicate that research designed to plan interventions in caregivers must not ignore potential racial differences with regard to the effects of caregiving on mental health

Caregiving, residence, race, and depressive symptoms

The objective of this study is to evaluate the psychological responses to caregiving between black and white dementia caregivers measured by self-reports of depressive symptoms evaluating the impact of sub-components of the Center for Epidemiologic Studies Depression Scale (CES-D) and residential arrangements of the caregiving dyad. The method included 87 intergenerational family caregivers enrolled in the Duke Caregiver Study (50 white and 37 black). Total CES-D and the four sub-components were modeled as dependent measures in separate linear regressions. Three models were examined. The first model tested race, living arrangements, and their interaction. The second model adjusted for age, gender, education, income, health status, cultural justification for caregiving, crime concerns, systolic blood pressure, diastolic blood pressure, and glycosylated hemoglobin. A third model added adjustment for caregiver burden. The results showed that there was a significant race by residence interaction for CES-D, somatic symptoms and depressive affect such that when the dyads are living apart – with the care recipient in their own home or in an institutional setting – whites reported more depressive symptoms than blacks. When the dyads lived together, this was reversed, and blacks reported higher depressive symptoms than whites. To conclude, all the parameters such as race, living arrangements, and the components of depression need to be taken into account to understand the impact of caregiving on the emotional health of caregivers

Socioeconomic Indices as Independent Correlates of C-Reactive Protein in the National Longitudinal Study of Adolescent Health

Examine the association between SES and C-reactive protein (CRP) to understand how SES may increase the risk of CVD and thus identify targets for prevention measures

Depression, Stressful Life Events, and the Impact of Variation in the Serotonin Transporter: Findings from the National Longitudinal Study of Adolescent to Adult Health (Add Health)

BackgroundThe low transcriptionally efficient short-allele of the 5HTTLPR serotonin transporter polymorphism has been implicated to moderate the relationship between the experience of stressful life events (SLEs) and depression. Despite numerous attempts at replicating this observation, results remain inconclusive.MethodsWe examined this relationship in young-adult Non-Hispanic white males and females between the ages of 22 and 26 (n = 4724) participating in the National Longitudinal Study of Adolescent to Adult Health (Add Health) with follow-up information every six years since 1995.ResultsLinear and logistic regression models, corrected for multiple testing, indicated that carriers of one or more of the S-alleles were more sensitive to stress than those with two L-alleles and at a higher risk for depression. This relationship behaved in a dose-response manner such that the risk for depression was greatest among those who reported experiencing higher numbers of SLEs. In post-hoc analyses we were not able to replicate an interaction effect for suicide ideation but did find suggestive evidence that the effects of SLEs and 5HTTLPR on suicide ideation differed for males and females. There were no effects of childhood maltreatment.DiscussionOur results provide partial support for the original hypothesis that 5-HTTLPR genotype interacts with the experience of stressful life events in the etiology of depression during young adulthood. However, even with this large sample, and a carefully constructed a priori analysis plan, the results were still not definitive. For the purposes of replication, characterizing the 5HTTLPR in other large data sets with extensive environmental and depression measures is needed

The impact of emotional well-being on long-term recovery and survival in physical illness: a meta-analysis

This meta-analysis synthesized studies on emotional well-being as predictor of the prognosis of physical illness, while in addition evaluating the impact of putative moderators, namely constructs of well-being, health-related outcome, year of publication, follow-up time and methodological quality of the included studies. The search in reference lists and electronic databases (Medline and PsycInfo) identified 17 eligible studies examining the impact of general well-being, positive affect and life satisfaction on recovery and survival in physically ill patients. Meta-analytically combining these studies revealed a Likelihood Ratio of 1.14, indicating a small but significant effect. Higher levels of emotional well-being are beneficial for recovery and survival in physically ill patients. The findings show that emotional well-being predicts long-term prognosis of physical illness. This suggests that enhancement of emotional well-being may improve the prognosis of physical illness, which should be investigated by future research