Economic evaluation of the introduction of rotavirus vaccine in Hong Kong.

BACKGROUND: Rotavirus is a common cause of severe gastroenteritis in young children in Hong Kong (HK) with a high economic burden. This study aimed to evaluate the cost-effectiveness of introducing rotavirus vaccination into the HK Government's Childhood Immunisation Programme (CIP) and to include the potential protective effect of the vaccine against seizures. METHODS: A decision-support model was customised to estimate the potential impact, cost-effectiveness and benefit-risk of rotavirus vaccination in children below 5 years over the period 2020-2029 in HK. Two doses of Rotarix® and three doses of RotaTeq® were each compared to no vaccination. Rotavirus treatment costs were calculated from a governmental health sector perspective (i.e., costs of public sector treatment) and an overall health sector perspective (both governmental and patient, i.e., costs of public sector treatment, private sector treatment, transport and diapers). We ran probabilistic and deterministic uncertainty analyses. RESULTS: Introduction of rotavirus vaccination in HK could prevent 49,000 (95% uncertainty interval: ~44,000-54,000) hospitalisations of rotavirus gastroenteritis and seizures and result in ~50 (95% uncertainty interval: ~25-85) intussusception hospitalisations, over the period 2020-2029 (a benefit-risk ratio of ~1000:1), compared to a scenario with no public or private sector vaccine use. The discounted vaccination cost would be US$51-57 million over the period 2020-2029 based on per-course prices of US$72 (Rotarix®) or US$78 (RotaTeq®), but this would be offset by discounted treatment cost savings of US$70 million (government) and US$127 million (governmental and patient health sector). There was a greater than 94% probability that the vaccine could be cost-saving irrespective of the vaccine product or perspective considered. All deterministic 'what-if' scenarios were cost-saving from an overall health sector perspective (governmental and patient). CONCLUSIONS: Rotavirus vaccination is likely to be cost-saving and have a favourable benefit-risk profile in HK. Based on the assumptions made, our analysis supports its introduction into CIP.

Birth weight and prematurity with lung function at ~17.5 years: "Children of 1997" birth cohort.

We aimed to determine if prematurity and lower birth weight are associated with poorer lung function in a non-western developed setting with less marked confounding by socioeconomic position. Using multivariable linear regression in Hong Kong's "Children of 1997" birth cohort, adjusted associations of prematurity and birth weight with forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and forced expiratory flow at 25-75% of the pulmonary volume (FEF25-75%) at ~17.5 years were assessed. Associations for birth weight were stronger in boys for FEV1 (boys: 0.31 L, 95% confidence interval (CI) 0.24 to 0.38, girls: 0.18 L, 95% CI 0.12 to 0.25), FVC (boys: 0.36 L, 95% CI 0.27 to 0.44, girls: 0.22 L, 95% CI 0.15 to 0.28) and FEF25-75% (boys: 0.35 L, 95% CI 0.21 to 0.49, girls: 0.22 L, 95% CI 0.09 to 0.34) adjusted for age, socioeconomic position and infant and maternal characteristics. Similarly adjusted, preterm birth (compared to full-term birth) was associated with lower FEV1/FVC and FEF25-75%. Thus, associations of lower birth weight, especially in boys, and prematurity with poorer lung function at 17.5 years were found. Identifying underlying mechanism might contribute to the improvement of pulmonary health and the prevention of adult respiratory illness.

The effect of liver enzymes on adiposity: a Mendelian randomization study.

Poorer liver function is positively associated with diabetes in Mendelian randomization (MR) studies. Observationally, adiposity is associated with poorer liver function. To clarify the etiology, we assessed the association of liver enzymes with adiposity observationally and using two-sample MR for validation. In the "Children of 1997" birth cohort, we used multivariable linear regression to assess the associations of alanine transaminase (ALT) and alkaline phosphatase (ALP) at ~17.5 years with body mass index (BMI) (n = 3,458). Using MR, genetic predictors of ALT, ALP and gamma glutamyltransferase (GGT), were applied to genome-wide association studies of BMI (n = 681,275), waist circumference (WC) (n = 224,459) and waist-hip ratio (WHR) (n = 224,459) to obtain unconfounded estimates. Observationally, ALT was positively associated with BMI (0.10 kg/m2 per IU/L, 95% confidence interval (CI) 0.09 to 0.11). ALP was inversely associated with BMI (-0.018 kg/m2 per IU/L, 95% CI -0.024 to -0.012). Using MR, ALT was inversely associated with BMI (-0.14 standard deviation per 100% change in concentration, 95% CI -0.20 to -0.07), but not WC or WHR. ALP and GGT were unrelated to adiposity. Poorer liver function might not cause adiposity; instead higher ALT might reduce BMI, raising the question as to the role of ALT in body composition.

The Roles of 27 Genera of Human Gut Microbiota in Ischemic Heart Disease, Type 2 Diabetes Mellitus, and Their Risk Factors: A Mendelian Randomization Study.

Manipulation of the gut microbiota presents a new opportunity to combat chronic diseases. Randomized controlled trials of probiotics suggest some associations with adiposity, lipids, and insulin resistance, but to our knowledge no trials with "hard" outcomes have been conducted. We used separate-sample Mendelian randomization to obtain estimates of the associations of 27 genera of gut microbiota with ischemic heart disease, type 2 diabetes mellitus, adiposity, lipid levels, and insulin resistance, based on summary data from CARDIoGRAAMplusC4D and other consortia. Among the 27 genera, a 1-allele increase in single nucleotide polymorphisms related to greater abundance of Bifidobacterium was associated with lower risk of ischemic heart disease (odds ratio = 0.985, 95% confidence interval (CI): 0.971, 1.000; P = 0.04), a 0.011-standard-deviation lower body mass index (95% CI: -0.017, -0.005), and a 0.026-standard-deviation higher low-density lipoprotein cholesterol level (95% CI: 0.019, 0.033), but the findings were not robust to exclusion of potential pleiotropy. We also identified Acidaminococcus, Aggregatibacter, Anaerostipes, Blautia, Desulfovibrio, Dorea, and Faecalibacterium as being nominally associated with type 2 diabetes mellitus or other risk factors. Results from our study indicate that these 8 genera of gut microbiota should be given priority in future research relating the gut microbiome to ischemic heart disease and its risk factors.

Birth weight, gestational age and late adolescent liver function using twin status as instrumental variable in a Hong Kong Chinese birth cohort: "Children of 1997".

Birth weight (BW) is inversely associated with diabetes and liver function in Mendelian Randomization studies. Observationally, lower BW is usually also associated with poorer liver function. However, these studies could be confounded by socioeconomic position. Here we assessed if BW is associated with liver function in a unique population with little socio-economic patterning of BW, using both instrumental variable and an observational analysis. We used instrumental variable analysis (IVA) to assess the association of BW with liver function (alanine transaminase (ALT), alkaline phosphatase (ALP), bilirubin, and albumin) at ~17 years with twin status as an instrumental variable in the prospective population-representative "Children of 1997" birth cohort (n = 8327). We also conducted an observational analysis adjusted for sex, maternal age, maternal migrant status, smoking and parental socio-economic position. A generalized linear model with gamma family was used for ALT, ALP, and bilirubin because they are not normally distributed. Using IVA, BW was not associated with ALT, ALP or bilirubin, but was possibly negatively associated with albumin (-1.12 g/L, 95% confidence interval (CI) -2.08 to -0.16). Observationally, BW was negatively associated with ALT (-1.23 IU/L, 95% CI -2.16 to -0.30), ALP (-1.72 IU/L, 95% CI -3.43 to -0.01) and higher albumin (-0.23 g/L, 95% CI -0.40 to -0.06). Poor liver function may be a pathway by which the risks of lower BW are actuated. This insight might help identify post-natal targets of intervention to mitigate the adverse health effects of lower birth weight.

The Effect of Birth Weight on Academic Performance: Instrumental Variable Analysis.

Observationally, lower birth weight is usually associated with poorer academic performance; whether this association is causal or the result of confounding is unknown. To investigate this question, we obtained an effect estimate, which can have a causal interpretation under specific assumptions, of birth weight on educational attainment using instrumental variable analysis based on single nucleotide polymorphisms determining birth weight combined with results from the Social Science Genetic Association Consortium study of 126,559 Caucasians. We similarly obtained an estimate of the effect of birth weight on academic performance in 4,067 adolescents from Hong Kong's (Chinese) Children of 1997 birth cohort (1997-2016), using twin status as an instrumental variable. Birth weight was not associated with years of schooling (per 100-g increase in birth weight, -0.006 years, 95% confidence interval (CI): -0.02, 0.01) or college completion (odds ratio = 1.00, 95% CI: 0.96, 1.03). Birth weight was also unrelated to academic performance in adolescents (per 100-g increase in birth weight, -0.004 grade, 95% CI: -0.04, 0.04) using instrumental variable analysis, although conventional regression gave a small positive association (0.02 higher grade, 95% CI: 0.01, 0.03). Observed associations of birth weight with academic performance may not be causal, suggesting that interventions should focus on the contextual factors generating this correlation.

A Mendelian randomization study of the effect of calcium on coronary artery disease, myocardial infarction and their risk factors.

Meta-analyses of randomized controlled trials (RCTs) suggest calcium could have adverse effects on cardiovascular disease, although these findings are controversial. To clarify, we assessed whether people with genetically higher calcium had a higher risk of coronary artery disease (CAD), myocardial infarction (MI) and their risk factors. We used a two-sample Mendelian randomization study. We identified genetic variants (single nucleotide polymorphisms (SNPs)) that independently contributed to serum calcium at genome-wide significance which we applied to large extensively genotyped studies of CAD, MI, diabetes, lipids, glycaemic traits and adiposity to obtain unconfounded estimates, with body mass index (BMI) as a control outcome. Based on 4 SNPs each 1 mg/dl increase in calcium was positively associated with CAD (odds ratio (OR) 1.49, 95% confidence interval (CI) 1.02-2.17), MI (OR 1.58, 95% CI 1.06-2.35), LDL-cholesterol (0.21 standard deviations, 95% CI 0.01-0.4), total cholesterol (0.21 standard deviations, 95% CI 0.03-0.38) and possibly triglycerides (0.19 standard deviations, 95% CI -0.1-0.48), but was unlikely related to BMI although the estimate lacked precision. Sensitivity analysis using 13 SNPs showed a higher risk for CAD (OR 1.87, 95% CI 1.14-3.08). Our findings, largely consistent with the experimental evidence, suggest higher serum calcium may increase the risk of CAD.

Effect of l-arginine, asymmetric dimethylarginine, and symmetric dimethylarginine on ischemic heart disease risk: A Mendelian randomization study.

BACKGROUND: l-arginine is a commonly consumed dietary conditional essential amino acid found in food items and supplements, which is closely related to asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA). l-arginine is thought to increase nitric oxide and be cardioprotective, whereas ADMA and SDMA may inhibit nitric oxide synthesis and increase cardiovascular disease risk. Unexpectedly, l-arginine increased mortality in a small trial. To clarify the effects of these potential targets of intervention, we assessed the risk of ischemic heart disease (IHD) by genetically determined l-arginine, ADMA, and SDMA. METHODS: Single nucleotide polymorphisms (SNPs) contributing to l-arginine, ADMA, and SDMA, at genome-wide significance, were applied to the CARDIoGRAMplusC4D 1000 Genomes-based genome-wide association study IHD case (n=60,801, ~70% myocardial infarction)-control (n=123,504) study. We obtained unconfounded estimates using instrumental variable analysis by combining the Wald estimators for each SNP, taking into account any correlation between SNPs using weighted generalized linear regression. RESULTS: Higher l-arginine was associated with higher risk of IHD (odds ratio [OR] 1.18 per SD increase, 95% CI 1.03-1.36) and of myocardial infarction (OR 1.29, 95% CI 1.10-1.51), based on 2 SNPs from MED23. Symmetric dimethylarginine had an OR of 1.07 per SD (95% CI 0.99-1.17) for IHD based on 5 SNPs from AGXT2. Asymmetric dimethylarginine had and OR of 1.08 per SD (95% CI 0.99-1.19) for IHD based on 4 SNPs from DDAH1. CONCLUSION: l-arginine could possibly cause IHD. Given that l-arginine occurs in many common dietary items, investigation of its health effect is required.

Liver Enzymes and Risk of Ischemic Heart Disease and Type 2 Diabetes Mellitus: A Mendelian Randomization Study.

We used Mendelian randomization to estimate the causal effects of the liver enzymes, alanine aminotransferase (ALT), alkaline phosphatase (ALP) and gamma glutamyltransferase (GGT), on diabetes and cardiovascular disease, using genetic variants predicting these liver enzymes at genome wide significance applied to extensively genotyped case-control studies of diabetes (DIAGRAM) and coronary artery disease (CAD)/myocardial infarction (MI) (CARDIoGRAMplusC4D 1000 Genomes). Genetically higher ALT was associated with higher risk of diabetes, odds ratio (OR) 2.99 per 100% change in concentration (95% confidence interval (CI) 1.62 to 5.52) but ALP OR 0.92 (95% CI 0.71 to 1.19) and GGT OR 0.88 (95% CI 0.75 to 1.04) were not. Genetically predicted ALT, ALP and GGT were not clearly associated with CAD/MI (ALT OR 0.74, 95% CI 0.54 to 1.01, ALP OR 0.86, 95% CI 0.64 to 1.16 and GGT OR 1.08, 95% CI 0.97 to 1.19). We confirm observations of ALT increasing the risk of diabetes, but cannot exclude the possibility that higher ALT may protect against CAD/MI. We also cannot exclude the possibility that GGT increases the risk of CAD/MI and reduces the risk of diabetes. Informative explanations for these potentially contradictory associations should be sought.

Birth weight and risk of ischemic heart disease: A Mendelian randomization study.

Low birth weight is a risk factor for cardiovascular disease. However, the association could be confounded by many factors. We used Mendelian randomization to clarify the role of birth weight in ischemic heart disease (IHD) and lipids. We used all 7 single nucleotide polymorphisms (SNPs) independently contributing to birth weight at genome wide significance (p < 5 × 10-8) in separate sample instrumental variable analysis to estimate the effect of birth weight on IHD using the CARDIoGRAMplusC4D 1000 Genomes based GWAS case (n = 60,801)-control (n = 123,504) study and on lipids using GLGC (n = 188,577). Higher genetically predicted birth weight was associated with lower risk of IHD (odds ratio (OR) 0.96 per 100 grams, 95% confidence interval (CI) 0.93 to 0.99), but the association was not robust to sensitivity analyses excluding SNPs related to height or use of weighted median methods. Genetically predicted birth weight was not associated with low density lipoprotein cholesterol or triglycerides, but was associated with lower high density lipoprotein cholesterol (-0.014 standard deviation, 95% CI -0.027 to -0.0005) and the association was more robust to the sensitivity analyses. Our study does not show strong evidence for an effect of birth weight on IHD and lipids.

Spironolactone and glucose metabolism, a systematic review and meta-analysis of randomized controlled trials.

Diabetes predicts cardiovascular disease (CVD); some drugs are effective for CVD prevention but increase the risk of diabetes. In a systematic review and meta-analysis of placebo-controlled trials, we assessed if spironolactone, a mineralocorticoid receptor antagonist, affected glycemic control. We searched PubMed using ("spironolactone" or "aldactone") and trial and ("glucose" or "diabetes" or "insulin" or "insulin resistance") until January 4, 2016. In total, 18 eligible trials were identified; 10 on fasting glucose, 8 on hemoglobin A1c (HbA1c), 7 on homeostatic model assessment (HOMA)-insulin resistance (IR), and 8 on insulin. Spironolactone increased HbA1c (0.16%, 95% confidence interval 0.02 to 0.30) but had no clear effect on fasting glucose, HOMA-IR, and insulin. A mechanistic randomized controlled trial in people with and without diabetes might provide insight concerning these pleiotropic effects on diabetes and CVD relevant to prevention of both diseases.

Age at Onset of Puberty and Adolescent Depression: "Children of 1997" Birth Cohort.

OBJECTIVE: Timing of onset of puberty has fallen, with profound and detrimental consequences for health. We examined the associations of earlier onset of puberty with the presence of depression in early to middle adolescence. METHODS: The study examined prospective adjusted associations of age at onset of puberty, based on clinically assessed Tanner stage for breast/genitalia and pubic hair development, and self-reported presence of depression, assessed from the 9-item Patient Health Questionnaire on average at 13.6 years (n = 5795 [73%]). These factors were examined by using multivariable logistic regression in a population-representative Hong Kong Chinese birth cohort (ie, the "Children of 1997"). We also assessed whether associations varied according to gender. RESULTS: Association of age at onset of breast/genitalia development with the presence of depression varied according to gender. Earlier onset of breast development was associated with higher risk of the presence of depression (odds ratio, 0.83 per 1 year increase in age of onset [95% confidence interval, 0.70 to 0.98]) adjusted for age, socioeconomic position, mother's place of birth, birth order, secondhand smoke exposure, parental age, survey mode, gender-specific birth weight z score, BMI z score at 7 years, and parental marital status. In boys, similarly adjusted, age at onset of genitalia development was unrelated to the presence of depression. Earlier age at onset of pubic hair development was unrelated to the presence of depression in girls and boys. CONCLUSIONS: Early onset of breast development was associated with high risk of the presence of depression. Whether these findings are indicators of the effects of hormones or transient effects of social pressures remain to be determined.

Brief Report: Maternal Age of Menarche and Adiposity: Evidence from Hong Kong's "Children of 1997" Birth Cohort.

BACKGROUND: Earlier age of menarche predicts chronic diseases. Earlier maternal age of menarche is also associated with higher body mass index (BMI) and height into childhood. METHODS: We used generalized estimating equations in Hong Kong's "Children of 1997" birth cohort to examine the adjusted association of maternal age of menarche with BMI and height z score, and whether associations varied by maternal birthplace. RESULTS: Earlier maternal age of menarche was not associated with infant BMI but was associated subsequently with higher BMI in childhood and at puberty. Maternal age of menarche was negatively associated with height in children of Hong Kong-born mothers, but positively associated with infant length for children with mothers born in China (P value for interaction 0.02). CONCLUSION: These different patterns suggest drivers of adiposity and linear growth differ, and are more influential in some circumstances. Understanding these drivers may indicate setting-specific interventions to prevent childhood obesity.

Cigarette smoking and testosterone in men and women: A systematic review and meta-analysis of observational studies.

Recently Health Canada and the Food and Drug Administration warned about the cardiovascular risk of testosterone, making environmental drivers of testosterone potential prevention targets. Cotinine, a tobacco metabolite, inhibits testosterone breakdown. We assessed the association of smoking with testosterone in a systematic review and meta-analysis, searching PubMed and Web of Science through March 2015 using ("testosterone" or "androgen" or "sex hormone") and ("smoking" or "cigarette"). Two reviewers independently searched, selected, assessed quality and abstracted with differences resolved by consensus or reference to a third reviewer. The initial search yielded 2881 studies; 28 met the selection criteria. In 22 studies of 13,317 men, mean age 18-61years, smokers had higher mean testosterone than non-smokers (1.53nmol/L, 95% confidence interval (CI) 1.11 to 1.96) using a random effects model with inverse variance weighting. In 6 studies of 6089 women, mean age 28-62years, smoking was not clearly associated with testosterone (0.11nmol/L, 95% CI -0.08 to 0.30). Fixed effects models provided similar results, but suggested a positive association in women. Whether products which raise cotinine, such as e-cigarettes or nicotine replacement, also raise testosterone, should be investigated, to inform any regulatory action for e-cigarettes, which emit nicotine into the surrounding air, with relevance for both active and passive smokers.

Mode of delivery and adiposity: Hong Kong's "Children of 1997" birth cohort.

PURPOSE: To examine whether mode of delivery was associated with childhood adiposity in a developed non-Western context. METHODS: We used generalized estimating equations to estimate the association of mode of delivery (vaginal or cesarean) with body mass index (BMI) z-score and overweight (including obesity) from 3 months to 13 years, in 7809 term birth (94% follow-up) from a population-representative Chinese birth cohort, "Children of 1997." We used multiple imputation for missing data. RESULTS: The cesarean section rate (26%) was higher for children born in private hospitals, with lower gestational age, lower birth order, higher maternal age, higher maternal BMI, and higher family socioeconomic position. Cesarean section was not associated with BMI z-score from 3 months to 13 years (mean difference, 0.03; 95% confidence interval, -0.02 to 0.09) or overweight from 3 years to 13 years (odds ratio, 0.98; 95% confidence interval, 0.77 to 1.25) after adjusting for infant and maternal characteristics and family socioeconomic position. CONCLUSIONS: In a non-Western developed setting, mode of delivery was not clearly associated with BMI or overweight (including obesity) into late childhood. From a public health perspective, the role of mode of delivery and its mechanistic pathway in the current burgeoning epidemic of obesity needs to be clarified.

Simulated growth trajectories and blood pressure in adolescence: Hong Kong's Chinese Birth Cohort.

BACKGROUND: Patterns and amounts of growth may determine adult blood pressure. Growth at different phases is correlated and affects current size, making effects on blood pressure difficult to distinguish. We decomposed growth to 13 years into independent associations with blood pressure and estimated how reaching the same size by different routes could affect adolescent blood pressure. METHODS: Using estimates from partial least squares for the associations of birth weight, height, and BMI at 3 months, growth at 3-9 months, 9-36 months, 3-8 years and 8-13 years and size at 13 years with SBP and DBP in 5247 term births (67% follow-up) from Hong Kong's 'Children of 1997' Birth Cohort, we estimated SBP and DBP at 13 years for 99 simulated growth trajectories resulting in the same size using nonparametric bootstrapping. RESULTS: High birth weight followed by slower growth was associated with lower SBP in both sexes and DBP in boys. Greater height to 3 years followed by slower height growth was associated with lower SBP in boys. Higher BMI until 9 months followed by slower BMI growth was associated with lower blood pressure in boys. CONCLUSION: High birth weight or larger early size was associated with lower blood pressure if followed by slower later growth, consistent with the fetal origin hypothesis. However, whether these patterns are due to fetal and infant metabolic programming or to allowing slower growth at periods when rapid growth is harmful is unknown.

Timing of solid food introduction and obesity: Hong Kong's "children of 1997" birth cohort.

BACKGROUND: Some observational studies in Western settings show that early introduction of solid food is associated with subsequent obesity. However, introduction of solid food and obesity share social patterning. We examined the association of the timing of the introduction of solid food with BMI and overweight (including obesity) into adolescence in a developed non-Western setting, in which childhood obesity is less clearly socially patterned. METHODS: We used generalized estimating equation models to estimate the adjusted associations of the timing of the introduction of solid food (<3, 3-4, 5-6, 7-8, and >8 months) with BMI z score and overweight (including obesity) at different growth phases (infancy, childhood, and puberty) in 7809 children (88% follow-up) from a Chinese birth cohort, "Children of 1997." We assessed if the associations varied with gender or breastfeeding. We used multiple imputation for missing exposure and confounders. RESULTS: The introduction of solid food at <3 months of age was associated with lower family socioeconomic position (SEP) but was not clearly associated with BMI or overweight (including obesity) in infancy [mean difference in BMI z score: 0.01; 95% confidence interval (CI): -0.14 to 0.17], childhood (0.14; 95% CI: -0.11 to 0.40), or at puberty (0.22; 95% CI: -0.07 to 0.52), adjusted for SEP and infant and maternal characteristics. CONCLUSIONS: In a non-Western developed setting, there was no clear association of the early introduction of solid food with childhood obesity. Together with the inconsistent evidence from studies in Western settings, this finding suggests that any observed associations might simply be residual confounding by SEP.

Lifetime growth and blood pressure in adolescence: Hong Kong's "Children of 1997" birth cohort.

OBJECTIVES: Blood pressure tracks from adolescence to adulthood and is positively associated with low birth weight and faster infant growth. Most observations are from Western populations; it is unclear whether these are biologically based or contextually specific. We examined the associations of growth with blood pressure in adolescence. METHODS: Multivariable partial least squares regression was used to assess the associations of growth to ~11 years with blood pressure at ~11 years in 5813 term births from Hong Kong's Children of 1997 birth cohort. Growth was considered as gender- and age-specific z-scores for birth weight, BMI, and length at 3 months; change in z-scores for BMI and height at 3 to 9 months, 9 to 36 months, 3 to 7 years, and 7 to 11 years; and BMI and height at 11 years. RESULTS: Birth weight was weakly inversely associated with systolic blood pressure in girls -0.58 mm Hg 95% confidence interval -1.05 to -0.12 (boys -0.21, -0.71 to 0.30). Childhood growth, particularly linear growth at 7 to 11 years (girls: 1.27, 0.56 to 1.98; boys 2.11, 1.39 to 2.83), as well as current height (girls: 2.40, 2.04 to 2.76, boys: 2.65, 2.29 to 3.01) and BMI (girls: 2.72, 2.35 to 3.09, boys: 2.72, 2.09 to 3.36) were associated with higher systolic blood pressure. Diastolic blood pressure was also positively associated with current size. CONCLUSIONS: In the first study to examine simultaneously the role of pre- and postnatal growth in adolescent blood pressure, the role of late childhood growth predominated.

Pubertal muscle mass and diabetes markers in Chinese adolescents.

OBJECTIVES: Diabetes is common in China despite a relatively nonobese population. We hypothesized that testosterone driven muscle mass acquisition at puberty may be relevant. We examined the associations of testosterone with muscle mass and of muscle mass with fasting glucose in Chinese adolescents. METHODS: In 40 adolescents (20 boys and 20 girls, age 12.9 ± 0.1 years) from Hong Kong's "Children of 1997" birth cohort, we used multivariable linear regression to assess adjusted associations of testosterone and fasting glucose (from a morning blood sample) with muscle and fat mass from a dual-energy X-ray absorptiometry scan. RESULTS: Testosterone was positively associated with muscle mass (0.05 kg, 95% confidence interval (CI) 0.01 to 0.09, per pg/ml testosterone). Muscle mass was associated with lower glucose (-0.04 mmol/l, 95% CI -0.08 to -0.01 per kg muscle mass) adjusted for sex and fat mass. CONCLUSIONS: Environmentally driven muscle mass acquisition at puberty could influence diabetes.