Mirko Döhnert

The LIFE child study: a life course approach to disease and health

BackgroundProfound knowledge about child growth, development, health, and disease in contemporary children and adolescents is still rare. Epidemiological studies together with new powerful research technologies present exciting opportunities to the elucidation of risk factor-outcome associations with potentially major consequences for prevention, diagnosis and treatment.AimTo conduct a unique prospective longitudinal cohort study in order to assess how environmental, metabolic and genetic factors affect growth, development and health from fetal life to adulthood.MethodsThe ‘Leipzig Research Centre for Civilization Diseases (LIFE) Child Study’ focuses on two main research objectives: (1) monitoring of normal growth, development and health; (2) non-communicable diseases such as childhood obesity and its co-morbidities, atopy and mental health problems. Detailed assessments will be conducted alongside long-term storage of biological samples in 2,000 pregnant women and more than 10,000 children and their families.ResultsClose coordination and engagement of a multidisciplinary team in the LIFE Child study successfully established procedures and systems for balancing many competing study and ethical needs. Full participant recruitment and complete data collection started in July 2011. Early data indicate a high acceptance rate of the study program, successful recruitment strategies and the establishment of a representative cohort for the population of Leipzig. A series of subprojects are ongoing, and analyses and publications are on their way.DiscussionThis paper addresses key elements in the design and implementation of the new prospective longitudinal cohort study LIFE Child. Given the recognized need for long-term data on adverse effects on health and protective factors, our study data collection should provide magnificent opportunities to examine complex interactions that govern the emergence of non-communicable diseases.

The hyporeactivity of salivary cortisol at stress test (TSST-C) in children with internalizing or externalizing disorders is contrastively associated with α-amylase

BACKGROUND Stress biomarkers of the autonomic nervous system and hypothalamic-pituitary-adrenal axis (HPA-axis) can be measured via alpha-amylase (AA) and cortisol and cortisone in saliva. Objectives were to determine 1) the response patterns of cortisol, cortisone, and AA under both circadian conditions and the Trier Social Stress Test for Children (TSST-C), 2) which reactivity index is most suitable to differentiate internalizing or externalizing disorders from controls, and to explore 3) the interaction between AA and cortisol in the presence of internalizing or externalizing disorders. METHODS Saliva samples (n = 2893) from children with internalizing (n = 55) or externalizing disorders (n = 33) and healthy children (n = 81) were analyzed for cortisol, cortisone, and AA under circadian conditions and TSST-C. RESULTS Circadian rhythm of three biomarkers did not differ between diagnostic groups. Age and gender were significant predictors for cortisol and awakening time influenced all three biomarkers significantly. TSST-C responses appeared sequentially in the order of AA, cortisol, and cortisone. Trajectories of cortisol and cortisone responses, not in AA, were significantly lower in children with internalizing or externalizing disorders than in healthy children. Cortisol percentage increase appeared to be the most suitable reactivity index to detect the difference between the diagnostic groups. Internalizing disorders had a negative association between AA decrease and cortisol increase (β = -.199, p < .05, R(2) = .304). Externalizing disorders had a positive association between AA baseline and cortisol increase (β = .229, p < .05, R(2) = .304). CONCLUSION An altered HPA-axis response during stress might result from chronic allostatic load in internalizing disorders and underaroused stress response system in externalizing disorders.

The acceptance of the K‐SADS‐PL – potential predictors for the overall satisfaction of parents and interviewers

The presented study investigated the interviewee (parents) and interviewer acceptance of the semi‐structured diagnostic interview Kiddie Schedule for Affective Disorders and Schizophrenia for School Aged Children Present Lifetime version (KSADS‐PL; German version). Seventeen certified interviewers conducted 231 interviews (interviewers conducted several interviews; interviewees were only questioned once). Interviewees and interviewers anonymously rated their acceptance right after the interview was finished. The nested data structure was analysed regarding an individual interviewer bias and potential predictors of overall satisfaction. Therefore, factors improvable by interviewer training were included, as well as fixed factors which cannot be improved by professional training. The overall satisfaction was evaluated as highly positive with significant higher interviewee and interviewer ratings in the research as compared to the clinical recruitment setting. An individual bias of the interviewer on his or her own acceptance over time, but not on the evaluation of the corresponding interviewee was found. Neither the professional background nor the gender of the interviewer had a significant contribution in predicting these differences. The interviewer model showed no significant change over time and only the interview duration and the interviewee acceptance were significant predictors for interviewer overall satisfaction. Regarding the interviewee model, just the interviewer acceptance was a significant predictor. Copyright Copyright

Attenuated LPP to Emotional Face Stimuli Associated with Parent- and Self-Reported Depression in Children and Adolescents

Individuals diagnosed with a depressive disorder have been found to show reduced reactions to emotional information consistent with the hypothesis of an emotional context insensitivity. However, there are contradictory findings of enhanced reactivity and mood-congruent processing. Electroencephalography (EEG) recordings of the late positive potential (LPP) can display such blunted or enhanced activity. Due to these contradictory findings, there is a need to clarify the role of the LPP in the emergence and presence of depressive disorders especially in children. We used an emotional Go/NoGo task to investigate modulations of the LPP to emotional (fearful, happy, sad) and calm faces in a sample of children and adolescents (age 11;00–14;11) diagnosed with a depressive disorder according to diagnostic parent interviews (K-SADS-PL) (n = 26) compared to a group of age-matched healthy controls (n = 26). LPP positivity was attenuated in children and adolescents with a depressive disorder as well as with higher self-reported depressive symptoms, suggesting reduced reactivity to emotional and calm faces. This is the first study to find generally blunted LPP responses in a clinical sample of depressed youth across reporters. Such dysfunctional modulation of neural activity may represent a potential biomarker for depressive disorders. The results call for further prospective studies investigating the course of the LPP before and after the onset of a depressive disorder in youth.

Feeding, eating and behavioral disturbances in Prader-Willi syndrome and non-syndromal obesity

Abstract Background: Although most individuals with Prader-Willi syndrome (PWS) are obese, little is known about the impact of obesity-related psychosocial factors in PWS. In the present study we compared feeding, eating, and behavioral disturbances in children and adolescents with PWS, peers with non-syndromal obesity, and normal weight controls. Methods: Twelve persons with PWS, aged 7–22 years, age- and gender-matched obese and normal weight individuals were analyzed regarding parental feeding practices, eating disturbances, and behavioral problems via standardized questionnaires. Results: Parents of individuals with PWS reported significantly more restrictive feeding and monitoring than did parents of obese or normal weight children without PWS (p<0.05). Social problems were more common in the obese and the PWS group than in the normal-weight group (p<0.05). Behavioral problems were significantly correlated with parental restrictive feeding practices. Conclusions: Our data show that children and adolescents with PWS are affected by psychosocial problems, and that restrictive feeding practices might be associated with more severe behavioral problems. Further studies in larger samples will be necessary to replicate these results and possibly provide new therapeutic approaches for the management of PWS.