Stress in childhood and the risk of type 1 diabetes

Abstract: Background: It is still unknown why children develop type 1 diabetes (T1D), although both genetic predisposition and environmental factors seems to be involved. Stress has been suggested as one environmental factor contributing to the development of T1D since the stress hormones may increase the need for insulin or increase insulin resistance. The family is important for the child’s emotional security, development, and regulation of emotions, hence stress among the parent’s may influence the child’s experiences of stress and coping with stressors.Aim: The aim of the current thesis was to evaluate self--‐assessment measurements of psychological stress in the family and to investigate if psychological stress in the family is involved in the development of childhood T1D.Methods: The All Babies in Southeast Sweden (ABIS) study is a prospective cohort study following children born in southeast Sweden between 1997 and 1999. All parents of children born in the region, approximately 21600 were asked to participate. In total, questionnaire data has been obtained from n=16142 (response rate approximately 75%) in some of the six data--‐collections and between 15845 (73%) and 4022 (19%) at each data collection. Psychological stress in the family was measured by questionnaires assessing: Serious life events experienced by the child and the parent, parenting stress, parental dissatisfaction, parental worries, the parent’s adult attachment, and the parents’ social support. Identification of cases with T1D was done through the national register SweDiabKids. At Dec the 31st 2012 had in total 104 (0,64%) children been diagnosed with T1D. Diabetes--‐cases included in the study samples was n=42 and n=58.Results: Parenting stress, parental worries, and size of social support were judged as reliable measurements assessing different aspects of psychological stress in the family, as well as they were all associated to children’s mental health in early adolescence. A serious life event experienced in childhood (measured by checklist at age 5--‐6, 8 and 10--‐ 14 years) was associated with an increase in risk for manifest T1D up to 13--‐15 years of age. None of the variables measuring psychological stress among parents were found to associate with risk of T1D.Conclusions: In addition to a checklist assessing serious life events experienced by the child is self--‐assessment measurements of parenting stress, parental worries and the parent’s social support be useful in large--‐scale studies as proxies for psychological stress of the child. The current study is the first unbiased prospective study that can confirm an association between the experience of a serious life event and increased risk of T1D. The result was independent of the child’s BMI and the parents’ educational level. Our results gives us strong reason to believe that psychological stress caused by serious life events can play a part in the immunological process leading to the onset of T1D.