Childhood height, adult height, and the risk of prostate cancer

PURPOSE: We previously showed that childhood height is positively associated with prostate cancer risk. It is, however, unknown whether childhood height exerts its effects independently of or through adult height. We investigated whether and to what extent childhood height has a direct effect on the risk of prostate cancer apart from adult height. METHODS: We included 5,871 men with height measured at ages 7 and 13 years in the Copenhagen School Health Records Register who also had adult (50–65 years) height measured in the Danish Diet, Cancer and Health study. Prostate cancer status was obtained through linkage to the Danish Cancer Registry. Direct and total effects of childhood height on prostate cancer risk were estimated from Cox regressions. RESULTS: From 1996 to 2012, 429 prostate cancers occurred. Child and adult heights were positively and significantly associated with prostate cancer risk. When adjusted for adult height, height at age 7 years was no longer significantly associated with the risk of prostate cancer. Height at 13 years was significantly and positively associated with prostate cancer risk even when adult height was adjusted for; per height z-score the hazard ratio was 1.15 [95 % confidence interval (CI) 1.01–1.32]. CONCLUSIONS: The effect of height at 13 years on the risk of prostate cancer was not entirely mediated through adult height, suggesting that child height and adult height may be associated with prostate cancer through different pathways

Childhood body mass index growth trajectories and endometrial cancer risk

Previously, we found that excess weight already in childhood has positive associations with endometrial cancer; however, associations with changes in body mass index (BMI) during childhood are not well understood. Therefore, we examined whether growth in childhood BMI is associated with endometrial cancer and its sub‐types. A cohort of 155,505 girls from the Copenhagen School Health Records Register with measured weights and heights at the ages of 6–14 years and born 1930–1989 formed the analytical population. BMI was transformed to age‐specific z scores. Using linear spline multilevel models, each girl's BMI growth trajectory was estimated as the deviance from the average trajectory for three different growth periods (6.25–7.99, 8.0–10.99, 11.0–14.0 years). Via a link to health registers, 1,020 endometrial cancer cases were identified, and Cox regressions were performed. A greater gain in BMI during childhood was positively associated with endometrial cancer but no differences between the different growth periods were detected in models adjusted for baseline BMI. The hazard ratios for the associations with overall growth during childhood per 0.1 z score increase were 1.15 (95% confidence interval [CI]: 1.07–1.24) for all endometrial cancers, 1.12 (95% CI: 1.04–1.21) for estrogen‐dependent cancers, 1.16 (95% CI: 1.06–1.26) for endometrioid adenocarcinomas and 1.46 (95% CI: 1.16–1.84) for non‐estrogen‐dependent cancers. Growth in BMI in early life is positively linked to later endometrial cancer risk. We did not identify any sensitive childhood growth period, which suggests that excess gain in BMI during the entire childhood period should be avoided

Birthweight, Childhood Body Mass Index, Height and Growth, and Risk of Polycystic Ovary Syndrome

Introduction: Adult obesity is linked with polycystic ovary syndrome (PCOS), but the importance of body size at ages before PCOS is diagnosed is unknown. Objective: To investigate associations between a woman’s own birthweight, childhood body mass index (BMI), height and growth patterns in relation to her risk of PCOS. Methods: We included 65,665 girls from the Copenhagen School Health Records Register, born in the period 1960–1996, with information on birthweight and measured weight and height at the ages of 7–13 years. Overweight was defined using International Obesity Task Force (IOTF) criteria. From the Danish National Patient Register, 606 women aged 15–50 years were identified. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated by Cox regression analysis. Results: Birthweight was not associated with PCOS. At the age of 7–13 years, girls with overweight had a higher risk of developing PCOS than girls without overweight; HR 2.83 (95% CI 2.34–3.42) at age 7 years and 2.99 (95% CI 2.38–3.76) at age 13 years. Furthermore, girls with overweight at both 7 and 13 years had a higher risk of developing PCOS than girls without overweight or overweight at only one age. Height was positively associated with PCOS risk at all ages. Girls who were persistently tall or changed from tall to average height had a higher risk of developing PCOS than girls with average height growth. Conclusion: Overweight and tall stature in childhood are positively associated with PCOS risk, but birthweight is not

Ethnic inequalities in overweight and obesity prevalence among copenhagen schoolchildren from 2002 to 2007

Background: The stabilization in levels of childhood overweight has masked increasing gaps among different ethnic and socioeconomic groups in several countries. Objective: To examine if levels and trends in childhood overweight and obesity differed by ethnicity and socioeconomic areas in Copenhagen schoolchildren. Methods: From measured heights and weights of 32,951 children 5-8 and 14-16 years of age, the prevalence of overweight (including obesity) and obesity were estimated using International Obesity Task Force criteria. Differences in prevalence levels and trends across six school years by ethnicity and socioeconomic areas were examined using logistic regression. Results: The prevalence of overweight significantly decreased from 2002 to 2007 among the youngest Western girls and boys, showed no significant changes among the oldest non-Western girls and increased among the oldest non-Western boys. In all years, the youngest non-Western children had significantly higher levels of overweight than Western children. Although the prevalence of overweight tended to be higher in low socioeconomic areas as compared with high socioeconomic areas, few differences were statistically significant. Consistent trends in overweight across the years by socioeconomic area were not observed. Conclusion: Ethnic and social inequalities exist in childhood overweight among Copenhagen schoolchildren; thus appropriate interventions targeting high-risk groups are neede