Issue 27 – Spring 2015

Childhood environment influences adrenarcheal timing among first-generation Bangladeshi migrant girls to the UK Houghton lC, Cooper gD, Booth M, Chowdhury oa, Troisi r, Ziegler rg, Katki Ha, Hoover rN & Bentley gr pLoS one 2014 oct 13;9(10):e109200 BaCKgrouND: adrenarche marks middle childhood at about 7 years of age. research examining British–Bangladeshi migrant women suggested that environmental conditions experienced before adrenarche influence adult reproductive function. This study investigated whether Bangladeshi children who migrate to the uK reach adrenarche earlier than non-migrants in Bangladesh or the uK. MeTHoDS: Healthy girls (aged 5–16 years) recruited from schools in Sylhet, Bangladesh, and london, uK, comprised four groups: Sylhetis (n= 165), first-generation migrants to the uK (n= 42), second-generation girls (n = 162), and British girls of european origin (n= 50). anthropometric measurements were collected with questionnaire data for migration and socioeconomic characteristics. Saliva samples were assayed for dehydroepiandrosterone (DHeaS) using elISas. Multiple linear regressions tested for group differences in anthropometric and socioeconomic variables and DHeaS levels. Median ages at adrenarche (DHeaS>400 pg/ml) were estimated using Weibull regression models for parametric survival analysis. Hazard ratios for reaching adrenarche earlier and 95% confidence intervals (CI), both unadjusted and adjusted for anthropometric variables, were estimated from the survival analyses. FINDINgS: First-generation migrants had a median age at adrenarche (5.3 years) that was significantly earlier than Sylheti (7.2), second-generation (7.4) and european (7.1) girls. In univariate analyses, first-generation girls reached adrenarche significantly earlier than Sylhetis [Hr(CI): 2.8 (1.4–5.5)]. In multivariate models, first-generation girls still reached adrenarche earlier than Sylhetis after adjusting for height [Hr(CI): 1.9 (0.9–4.1)] and weight [Hr(CI): 1.7 (0.8–3.8)], but these results were attenuated. CoNCluSIoNS: We suggest rapid catch-up growth experienced by first-generation girls during early childhood may explain their advanced adrenarche. The environmental conditions leading to earlier adrenarche, and the health implications of this early transition, merit further exploration. COMMENTARY Plasticity in developmental programming has evolved to provide the best chances of survival and reproductive success under changing environments. environmental conditions experienced in early life can profoundly influence human biology and long term health. Developmental origins of health and disease and life history transitions are purported to use placental, nutritional and endocrine cues for setting long term biological, mental and behavioural strategies in response to local ecological and/or social conditions.1 The window of developmental plasticity extends from preconception to early childhood and involves epigenetic responses to environmental changes, which exert their effects during life history phase transitions. This paper shows that environmental conditions experienced by British– Bangladeshi migrants before adrenarche influence adult reproductive function, and that rapid catch-up growth experienced by first-generation girls in early childhood may explain their advanced adrenarche. The adrenarcheal transition is a key event defining the transition from childhood to juvenility.2 Such life history transitions are when the child adaptively responds to environmental cues to enhance growth, body composition, lifespan, fecundity schedules and behavioural strategies that yield the highest fitness in a given environment.3 Here, we learn that childhood environment before adrenarche might represent a key period influencing adult reproductive function, that adrenarche itself might represent a critical childhood threshold for later life development, and that rapid catch-up growth might provide the switch for this cascade of events. 1. Hochberg Z et al. 2011 endocrine Reviews 32 159–224. 2. Hochberg Z 2008 archives of diseases of Childhood 93 534–539. 3. Hochberg Z 2009 european Journal of endocrinology 160 135–141. Société Suisse d’Endocrinologie-Diabétologie Pédiatrique The SSeDP (the Swiss Society for Paediatric endocrinology and Diabetology) was founded in 1993 and has 46 members, led by President Valérie Schwitzgebel. It has working groups covering two main areas: • Disorders of Sex Differentiation (DSD) – aiming to assess DSD epidemiology and quality of care in Switzerland (Co-ordinator Christa Flück; christa.flueck@dkf.unibe.ch) • growth Hormone register – initially involved in the Saghe Study, resulting in a national register of every child treated with recombinant human growth hormone in Switzerland since 1985 (Co-ordinator Primus Mullis; primus.mullis@insel.ch) There is also an ongoing collaborative project on monogenic diabetes, co-ordinated by Professor Schwitzgebel. The SSeDP organises an annual Meeting, as well as the eSPe advanced Seminar in Developmental endocrinology (arranged by Professor Mullis). eSPe and ISPaD (International Society for Pediatric and adolescent Diabetes) guidelines are currently followed in Switzerland. There are six centres of excellence with full fellowship programmes (the universities of Basel, Berne, geneva, lausanne and Zurich, and the Children’s Hospital of St gallen). The fellowship programme, including the learning goals, can be found at www.fmh.ch/bildung-siwf/fachgebiete/facharzttitel-und schwerpunkte/kinder-und-jugendmedizin.html. a national exam is mandatory after the 3-year fellowship for accreditation in paediatric endocrinology. For further information about SSeDP visit www.ssedp-sgped.ch or contact valerie.schwitzgebel@unige.ch.