Could the social environment trigger the induction of diabetes related autoantibodies in young children?

AIMS: The onset and progression of the autoimmune process leading to type 1 diabetes is partly dependent on genetic predisposition and partly on environmental factors. We have implemented a study design where 1-year-old children, from two equally sized, neighbouring but socioeconomically different cities, were compared for the induction of beta-cell autoantibodies. METHODS: This study comprises 2448 newborn infants, all living in the urban parts of the twin cities, followed prospectively with regular biological samples and questionnaires in a major population-based study. Of these, a random sample of 1497 children were tested for tyrosine phosphatase (IA-2A) and 1409 children for glutamic acid decarboxylase (GADA). Other documented risk factors of beta-cell autoimmunity and type 1 diabetes, such as family characteristics, dietary factors, and psychosocial factors were also included in the analysis. RESULTS: The risk for diabetes-related autoantibodies, both against GADA and IA-2A (>95% cut off), was significantly higher (p<0.0001) among children from the blue-collar than from the white-collar city. This difference persisted still after adjustment for other previously documented risk factors. Some of these previously known risk factors remained significant in the multivariate analysis as independent explanatory factors, in addition to living in a blue-collar city. CONCLUSIONS: Factors in the social environment could trigger the induction of diabetes-related autoantibodies in 1-year-old children. These results point out that our present knowledge of factors influencing the autoimmune process might be widen to also include factors in the social environment of the community.

Cortisol in hair measured in young adults - a biomarker of major life stressors?

BACKGROUND: Stress as a cause of illness has been firmly established. In public health and stress research a retrospective biomarker of extended stress would be an indispensible aid. The objective of this pilot study was to investigate whether concentrations of cortisol in hair correlate with perceived stress, experiences of serious life events, and perceived health in young adults. METHODS: Hair samples were cut from the posterior vertex area of (n = 99) university students who also answered a questionnaire covering experiences of serious life events, perceived Stress Scale and perceived health during the last three months. Cortisol was measured using a competitive radioimmunoassay in methanol extracts of hair samples frozen in liquid nitrogen and mechanically pulverised. RESULTS: Mean cortisol levels were significantly related to serious life events (p = 0.045), weakly negatively correlated to perceived stress (p = 0.025, r = -0.061) but nor affected by sex, coloured/permed hair, intake of pharmaceuticals or self-reported health. In a multiple regression model, only the indicator of serious life events had an independent (p = 0.041) explanation of increased levels of cortisol in hair. Out of four outliers with extremely high cortisol levels two could be contacted, both reported serious psychological problems. CONCLUSIONS: These findings suggest that measurement of cortisol in hair could serve as a retrospective biomarker of increased cortisol production reflecting exposure to major life stressors and possibly extended psychological illness with important implications for research, clinical practice and public health. Experience of serious life events seems to be more important in raising cortisol levels in hair than perceived stress.

Early psychosocial exposures, hair cortisol levels, and disease risk.

BACKGROUND: Early psychosocial exposures are increasingly recognized as being crucial to health throughout life. A possible mechanism could be physiologic dysregulation due to stress. Cortisol in hair is a new biomarker assessing long-term hypothalamic-pituitary-adrenal axis activity. The objective was to investigate whether early-life adverse psychosocial circumstances influence infant cortisol levels in hair and health outcomes in children prospectively until age 10. METHODS: A cohort study in the general community using a questionnaire covering 11 psychosocial items in the family during pregnancy and the cumulative incidence of diagnoses until age 10 years in 1876 children. Cortisol levels in hair were measured by using a radioimmunoassay in those with sufficient hair samples at age 1, yielding a subsample of n = 209. RESULTS: Children with added psychosocial exposures had higher infant cortisol levels in hair (B = 0.40, P < .0001, adjusted for gender and size for gestational age) in a cumulative manner and were significantly more often affected by 12 of the 14 most common childhood diseases, with a general pattern of increasing odds ratios. CONCLUSIONS: The findings support the model of physiologic dysregulation as a plausible mechanism by which the duration and number of early detrimental psychosocial exposures determine health outcomes. The model indicates that the multiplicity of adversities should be targeted in future interventions and could help to identify children who are at high risk of poor health. Furthermore, given the prolonged nature of exposure to a stressful social environment, the novel biomarker of cortisol in hair could be of major importance.

Maternal influence on child HPA axis: a prospective study of cortisol levels in hair.

OBJECTIVE: To investigate cortisol concentrations in hair as biomarker of prolonged stress in young children and their mothers and the relation to perinatal and sociodemographic factors. METHODS: Prospective cohort study of 100 All Babies In Southeast Sweden study participants with repeated measures at 1, 3, 5, and 8 years and their mothers during pregnancy. Prolonged stress levels were assessed through cortisol in hair. A questionnaire covered perinatal and sociodemographic factors during the child's first year of life. RESULTS: Maternal hair cortisol during the second and third trimester and child hair cortisol at year 1 and 3 correlated. Child cortisol in hair levels decreased over time and correlated to each succeeding age, between years 1 and 3 (r = 0.30, P = .002), 3 and 5 (r = 0.39, P < .001), and 5 and 8 (r = 0.44, P < .001). Repeated measures gave a significant linear association over time (P < .001). There was an association between high levels of hair cortisol and birth weight (ß = .224, P = .020), nonappropriate size for gestational age (ß = .231, P = .017), and living in an apartment compared with a house (ß = .200, P = .049). In addition, we found high levels of cortisol in hair related to other factors associated with psychosocial stress exposure. CONCLUSIONS: Correlation between hair cortisol levels in mothers and their children suggests a heritable trait or maternal calibration of the child's hypothalamic-pituitary-adrenocortical axis. Cortisol output gradually stabilizes and seems to have a stable trait. Cortisol concentration in hair has the potential to become a biomarker of prolonged stress, especially applicable as a noninvasive method when studying how stress influences children's health.