Puberty Timing and Adiposity Change Across Childhood and Adolescence

*Exact numbers and percentages not shown due to potential for disclosure.
^†Household social class was measured as the highest of the mother's or her partner's occupational social class using data on job title and details of occupation collected about the mother and her partner from the mother's questionnaire at 32 weeks of gestation. Social class was derived using the standard occupational classification (SOC) codes developed by the United Kingdom Office of Population Census and Surveys and classified as I professional, II managerial and technical, IIINM non-manual, IIIM manual, and IV and V part skilled occupations and unskilled occupations.
SD, standard deviation.

Association of age at peak height velocity (per year later) with fat mass at 9 years and change in fat mass 9–18 years in females and males separately. Mean trajectory is centred on the sex-specific mean of age at peak height velocity for each sex (age ~11.7 for females and age ~13.6 for males). The difference in fat mass per year of age at peak height velocity is back-transformed from the log scale for ease of interpretation and is a ratio of geometric means, expressed as a percentage difference. Adjusted for birth weight, gestational age, maternal education, parity, maternal smoking during pregnancy, maternal age, maternal pre-pregnancy BMI, household social class, marital status, partner education and breastfeeding.
*Mean height-adjusted fat mass at 9 and 18 in kilograms.
^†Percentage change per year in height-adjusted fat mass.
^‡Percentage difference in fat mass at 9 and 18 years per year later age at peak height velocity.
^§Percentage difference in change per year, per year later age at peak height velocity.
CI, confidence interval.

Association of age at peak height velocity (per year later) with change in fat mass before puberty, fat mass at puberty and change in fat mass after puberty in females and males separately. Mean trajectory is centred on the sex-specific mean of age at peak height velocity for each sex (age ~11.7 for females and age ~13.6 for males). The difference in fat mass per year of age at peak height velocity is back-transformed from the log scale for ease of interpretation and is a ratio of geometric means, expressed as a percentage difference. Models are adjusted for birth weight, gestational age, maternal education, parity, maternal smoking during pregnancy, maternal age, maternal pre-pregnancy BMI, household social class, marital status, partner education and breastfeeding.
*Percentage change per year in height-adjusted fat mass.
^†Mean height-adjusted fat mass at puberty.
^‡Percentage difference in change per year per year later age at peak height velocity.
^§Percentage difference in fat mass at puberty per year later age at peak height velocity.
CI, confidence interval.

Authors and Disclosures

Linda M. O'Keeffe^1–3,*, Monika Frysz^1,2, Joshua A. Bell^1,2, Laura D. Howe^1,2,† and Abigail Fraser<sup>1,2,†

1</sup>School of Public Health, University College Cork, Cork, Ireland ²MRC Integrative Epidemiology Unit at the University of Bristol, Bristol, UK ³Population Health Sciences, Bristol Medical School, Bristol, UK

*Correspondence address
School of Public Health, University College Cork, 4th Floor Western Gateway Building, Ireland. E-mail: linda.okeeffe@ucc.ie

^†These authors contributed equally to this work.

Authors' roles
L.M.O.K. designed the research. L.M.O.K. conducted the research, analysed the data and wrote the first draft of the paper. All authors critically revised the writing of the paper. L.M.O.K. had primary responsibility for the final content. A.F. and L.D.H. supervised the study.

Conflict of interest
None of the authors have any conflicts of interest to declare.