Nadya Dich

Childhood Cumulative Risk and Later Allostatic Load: Mediating Role of Substance Use

OBJECTIVE The present study investigated the long-term impact of exposure to poverty-related stressors during childhood on allostatic load, an index of physiological dysregulation, and the potential mediating role of substance use. METHOD Participants (n = 162) were rural children from New York State, followed for 8 years (between the ages 9 and 17). Poverty- related stress was computed using the cumulative risk approach, assessing stressors across 9 domains, including environmental, psychosocial, and demographic factors. Allostatic load captured a range of physiological responses, including cardiovascular, hypothalamic pituitary adrenal axis, sympathetic adrenal medullary system, and metabolic activity. Smoking and alcohol/drug use were tested as mediators of the hypothesized childhood risk-adolescent allostatic load relationship. RESULTS Cumulative risk exposure at age 9 predicted increases in allostatic load 8 years later. Smoking, but not alcohol and drug use, was a significant mediator of the prospective, longitudinal relationship between childhood cumulative risk and adolescent allostatic load. CONCLUSIONS The present paper contributes to the understanding of the role of early life stress in health across the life span and of the mechanisms by which adverse childhood environments impact health as children emerge into early adulthood. This knowledge will have implications for early intervention efforts.

Work stress, caregiving, and allostatic load: prospective results from the Whitehall II cohort study.

Objectives Studies investigating health effects of work and family stress usually consider these factors in isolation. The present study investigated prospective interactive effects of job strain and informal caregiving on allostatic load (AL), a multisystem indicator of physiological dysregulation. Methods Participants were 7007 British civil servants from the Whitehall II cohort study. Phase 3 (1991–1994) served as the baseline, and Phases 5 (1997–1999) and 7 (2002–2004) served as follow-ups. Job strain (high job demands combined with low control) and caregiving (providing care to aged or disabled relatives) were assessed at baseline. AL index (possible range, 0–9) was assessed at baseline and both follow-ups based on nine cardiovascular, metabolic, and immune biomarkers. Linear mixed-effect models were used to examine the association of job strain and caregiving with AL. Results High caregiving burden (above the sample median weekly hours of providing care) predicted higher AL levels, with the effect strongest in those also reporting job strain (b = 0.36, 95% confidence interval = 0.01–0.71); however, the interaction between job strain and caregiving was not significant (p = .56). Regardless of job strain, participants with low caregiving burden (below sample median) had lower subsequent AL levels than did non-caregivers (b = −0.22, 95% confidence interval = −0.06–−0.37). Conclusions The study provides some evidence for adverse effects of stress at work combined with family demands on physiological functioning. However, providing care to others may also have health protective effects if it does not involve excessive time commitment.

Impaired sleep and allostatic load: cross-sectional results from the Danish Copenhagen Aging and Midlife Biobank.

OBJECTIVE Understanding the mechanisms linking sleep impairment to morbidity and mortality is important for future prevention, but these mechanisms are far from elucidated. We aimed to determine the relation between impaired sleep, both in terms of duration and disturbed sleep, and allostatic load (AL), which is a measure of systemic wear and tear of multiple body systems, as well as with individual risk markers within the cardiac, metabolic, anthropometric, and immune system. METHODS A cross-sectional population-based study of 5226 men and women from the Danish Copenhagen Aging and Midlife Biobank with comprehensive information on sleep duration, disturbed sleep, objective measures of an extensive range of biological risk markers, and physical conditions. RESULTS Long sleep (mean difference 0.23; 95% confidence interval, 0.13, 0.32) and disturbed sleep (0.14; 0.06, 0.22) were associated with higher AL as well as with high-risk levels of risk markers from the anthropometric, metabolic, and immune system. Sub-analyses suggested that the association between disturbed sleep and AL might be explained by underlying disorders. Whereas there was no association between short sleep and AL, the combination of short and disturbed sleep was associated with higher AL (0.19; 0.08, 0.30) and high-risk levels of immune system markers. CONCLUSION Our study suggests small but significant differences in the distribution of allostatic load, a pre-clinical indicator of disease risk and premature death, for people with impaired relative to normal sleep. Impaired sleep may be a risk factor for developing disease and be a risk marker for underlying illness or sleep disorders.

Children's Emotionality Moderates the Association Between Maternal Responsiveness and Allostatic Load: Investigation Into Differential Susceptibility.

While emotionality is often thought of as a risk factor, differential susceptibility theory argues that emotionality reflects susceptibility to both positive and negative environmental influences. The present study explored whether emotional children might be more susceptible to the effects of both high and low maternal responsiveness on allostatic load, a physiological indicator of chronic stress. Participants were 226 mother and child dyads. Mothers reported on childrens emotionality at child age 9. Maternal responsiveness was measured at age 13 using self-reports and behavioral observation. Allostatic load was measured at age 13 and 17 using neuroendocrine, cardiovascular, and metabolic biomarkers. Emotionality was associated with higher allostatic load if self-reported responsiveness was low, but with lower allostatic load, when self-reported responsiveness was high.

Job strain and informal caregiving as predictors of long-term sickness absence: A longitudinal multi-cohort study

Objectives The aim of this study was to investigate the individual, joint and interactive effects of job strain and informal caregiving on long-term sickness absence with special attention to gender differences. Methods The study comprised a prospective cohort study of 6798 working adults from France, 14 727 from Finland, and 5275 from the UK. A total of 26 800 participants, age 52 (interquartile range 47-56) years participated in the study. Job strain was assessed using the demand-control model. Informal caregiving was defined as care for a sick, disabled, or elderly person. Long-term sickness absence spells defined as absence >14 consecutive days were registered during two years follow-up. We used recurrent-events Cox regression in random-effects meta-analyses. Results A total of 12% men and 21% women had ≥1 long-term sickness absence spell. Among women, both high job strain [hazard ratio (HR) 1.08, 95% confidence interval (95% CI) 1.00-1.17] and informal caregiving (HR 1.13, 95% CI 1.04-1.23) were associated with a modestly higher risk of sickness absence. Women doubly exposed to high job strain and informal caregiving also showed a moderately higher risk of sickness absence (HR 1.20, 95% CI 1.03-1.41), but the excess risk was not more than expected from joint exposure to caregiving and job strain. Neither job strain nor informal caregiving predicted sickness absence for men. Conclusions High job strain and informal caregiving predicted long-term sickness absence among women. However there was no noticeable interaction in the presence of both exposures.

Neighborhood perceptions and allostatic load: Evidence from Denmark.

An influential argument explaining why living in certain neighborhoods can become harmful to ones health maintains that individuals can perceive certain characteristics of the neighborhood as threatening and the prolonged exposure to a threatening environment could induce chronic stress. Following this line of argumentation, in the present study we test whether subjective perceptions of neighborhood characteristics relate to an objective measure of stress-related physiological functioning, namely allostatic load (AL). We use a large dataset of 5280 respondents living in different regions of Denmark and we account for two alternative mechanisms, i.e., the objective characteristics of the living environment and the socio-economic status of individuals. Our results support the chronic stress mechanisms linking neighborhood quality to health. Heightened perceptions of disorder and pollution were found related to AL and this relationship was particularly robust for women.

Children’s negative emotionality combined with poor self-regulation affects allostatic load in adolescence:

The present study examined the concurrent and prospective, longitudinal effects of childhood negative emotionality and self-regulation on allostatic load (AL), a physiological indicator of chronic stress. We hypothesized that negative emotionality in combination with poor self-regulation would predict elevated AL. Mothers reported on children’s emotionality (N = 239, 116 males) at age 9, and self-regulation was measured at age 9 using a standard behavioural index of delay of gratification. AL was measured at ages 9 and 17. The AL measure captured hypothalamic pituitary adrenal axis, sympathetic adrenal medullary system, cardiovascular, and metabolic activity. Our results confirmed that negative emotionality prospectively predicted increases in AL, but only in children with low levels of self-regulation. The findings suggest that the link between negative emotionality and stress physiology is moderated by self-regulation and contribute to understanding the role of negative emotionality in physiological functioning throughout childhood and adolescence.

A non-linear association between self-reported negative emotional response to stress and subsequent allostatic load: Prospective results from the Whitehall II cohort study

Previous research suggests that high levels of negative emotions may affect health. However, it is likely that the absence of an emotional response following stressful events may also be problematic. Accordingly, we investigated whether a non-linear association exists between negative emotional response to major life events and allostatic load, a multisystem indicator of physiological dysregulation. Study sample was 6764 British civil service workers from the Whitehall II cohort. Negative emotional response was assessed by self-report at baseline. Allostatic load was calculated using cardiovascular, metabolic and immune function biomarkers at three clinical follow-up examinations. A non-linear association between negative emotional response and allostatic load was observed: being at either extreme end of the distribution of negative emotional response increased the risk of physiological dysregulation. Allostatic load also increased with age, but the association between negative emotional response and allostatic load remained stable over time. These results provide evidence for a more nuanced understanding of the role of negative emotions in long-term physical health.

In Risky Environments, Emotional Children Have More Behavioral Problems but Lower Allostatic Load.

Objective: Developmental models of temperament by environment interactions predict that children’s negative emotionality exacerbates the detrimental effects of risky environments, increasing the risk for pathology. However, negative emotions may have an adaptive function. Accordingly, the present study explores an alternative hypothesis that in the context of high adversity, negative emotionality may be a manifestation of an adaptive coping style and thus be protective against the harmful effects of a stressful environment. Method: Prospective combined effects of negative emotionality and cumulative risk (confluence of multiple risk factors related to poverty) on children’s internalizing and externalizing symptoms and allostatic load, an index of cumulative physiological dysregulation, were assessed in 239 children (46% female, baseline age = 9). Negative emotionality and cumulative risk were assessed at baseline. Internalizing and externalizing behaviors were measured at 4- and 8-year follow-ups. Allostatic load was measured at baseline and both follow-ups using neuroendocrine, cardiovascular, and metabolic parameters. Linear mixed-effect models were used to analyze the prospective associations between negative emotionality, cumulative risk, and the outcomes—allostatic load and internalizing and externalizing behaviors. Results: The combination of high cumulative risk exposure and high negative emotionality was associated with highest levels of internalizing and externalizing behaviors. However, consistent with the alternative hypothesis, negative emotionality reduced the effects of high cumulative risk on allostatic load. Conclusions: In the context of risky environments, negative emotionality may offer some physical health benefits.

Informal caregiving and diurnal patterns of salivary cortisol: Results from the Whitehall II cohort study

The objective was to investigate the relationship between various aspects of informal caregiving and diurnal patterns of salivary cortisol, with special attention to the moderating effect of sex and work status. The study population was composed of 3727 men and women from the British Whitehall II study. Salivary cortisol was measured six times during a weekday. Aspects of caregiving included the relationship of caregiver to recipient, weekly hours of caregiving, and length of caregiving. Diurnal cortisol profiles were assessed using the cortisol awakening response (CAR) and diurnal cortisol slopes. Results showed that men, but not women, providing informal care had a blunted CAR compared with non-caregivers (PInteraction = 0.03). Furthermore, we found a dose-response relationship showing that more weekly hours of informal care was associated with a more blunted CAR for men (Ptrend = 0.03). Also, the blunted CAR for men was especially pronounced in short-term caregivers and those in paid work. In women, the steepest cortisol slope was seen among those in paid work who provided informal care (PInteraction = 0.01). To conclude, we found different cortisol profiles in male and female informal caregivers. Male caregivers had a blunted CAR, which has previously been associated with chronic stress and burnout. Future research should investigate whether results are generalizable beyond UK citizens with a working history in the civil service.