Waist-to-height ratio, waist circumference and BMI as indicators of percentage fat mass and cardiometabolic risk factors in children aged 3–7 years

SummaryObjectiveTo assess whether waist-to-height-ratio (WHtR) is a better estimate of body fat percentage (BF%) and a better indicator of cardiometabolic risk factors than BMI or waist circumference (WC) in young children.MethodsWHtR, WC and BMI were measured by trained staff according to standardized procedures. 2H2O and 2H218O isotope dilution were used to assess BF% in 61 children (3–7 years) from the general population, and bioelectrical impedance (Horlick equation) was used to assess BF% in 75 overweight/obese children (3–5 years). Cardiometabolic risk factors, including diastolic and systolic blood pressure, HOMA2-IR, leptin, adiponectin, triglycerides, total cholesterol, HDL- and LDL-cholesterol, TNFα and IL-6 were determined in the overweight/obese children.ResultsIn the children from the general population, after adjustments for age and gender, BMI had the highest explained variance for BF% compared to WC and WHtR (R2 = 0.32, 0.31 and 0.23, respectively). In the overweight/obese children, BMI and WC had a higher explained variance for BF% compared to WHtR (R2 = 0.68, 0.70 and 0.50, respectively). In the overweight/obese children, WHtR, WC and BMI were all significantly positively correlated with systolic blood pressure (r = 0.23, 0.30, 0.36, respectively), HOMA2-IR (r = 0.53, 0.62, 0.63, respectively), leptin (r = 0.70, 0.77, 0.78, respectively) and triglycerides (r = 0.33, 0.36, 0.24, respectively), but not consistently with other parameters.ConclusionIn young children, WHtR is not superior to WC or BMI in estimating BF%, nor is WHtR better correlated with cardiometabolic risk factors than WC or BMI in overweight/obese children. These data do not support the use of WHtR in young children

Parental correlations of physical activity and body mass index in young children-the GECKO Drenthe cohort

Background: Parental behavior can influence the development of overweight in children. The aim of this study is to examine whether parental BMI and parental physical activity are associated with BMI, waist circumference and physical activity in young children. Methods: In 3-4 year old children, weight, height and waist circumference were measured. Children's physical activity was measured in a subgroup (n = 299) using a tri-axial activity monitor, TracmorD. Data are represented as activity counts per minute (total physical activity) and as percentage of time in sedentary, light, moderate and vigorous intensity physical activity (generated from a subsample of Actigraph data using cut points from Butte et al.). Parental weight and height were self-reported and parental physical activity was assessed by the validated questionnaire SQUASH. Results: In total 1554 children (age 3.9 +/- 0.1 years, BMI 15.8 +/- 1.3 kg/m2 and waist circumference 52.4 +/- 3.5 cm) were included. Eleven percent were overweight or obese. A higher maternal BMI was related to higher levels of children's sedentary activity (r = 0.120, p = 0.04 and to lower levels of children's total and moderate physical activity (r = -0.158, p = 0.007 and r = -0.154, p = 0.008, respectively). Parental BMI was positively correlated with children's BMI and waist circumference (r = 0.20-0.27, p <0.001). Higher maternal total physical activity levels were not related to children's total physical activity level, but were related to higher levels of children's moderate and vigorous physical activity (rho = 0.132, p = 0.046 and rho = 0.132, p = 0.046, respectively). No correlations between total, moderate or vigorous physical activity levels of the parents with the child's BMI or waist circumference were found. Looking at physical activity domains maternal physical activity in active commuting, either walking or biking, showed a negative correlation with BMI of the child (rho = -0.062, p = 0.042). Conclusions: Higher maternal BMI and lower maternal physical activity levels were related to lower levels of children's physical activity. More active commuting by the mother and a lower parental BMI were related to a lower BMI of the children. Energy-balance related behavior of the parents may contribute to a healthier BMI of both preschool children and their parents

The validity of self-reported cancer in a population-based cohort compared to that in formally registered sources

Background: Self-reported cancer has been validated with heterogeneous results across populations. The aim was to assess the validity of self-reported cancer in the Lifelines population-based cohort and to search for explanations for not reporting cancer. Methods: Data from adult participants (n = 152,780) from Lifelines was linked to the Dutch-Nationwide pathology databank (PALGA), which has nearly 100% coverage of cancer diagnoses in the Netherlands and is considered as the gold standard for ascertainment of cancer diagnosis in this study. Sensitivity and positive predictive value (PPV) for self-reported cancers -reported as hand-written free text- were described. Logistic regressions analyses were performed to evaluate whether socio-demographic factors were associated with the presence of self-reported cancer when there was a diagnosis in PALGA. Results: 6611 (4.50%) participants had at least one self-reported diagnosis of cancer, where 9960 (6.97%) participants had at least one cancer diagnosis in PALGA. The sensitivity of self-reported cancer was 64.68% [95%CI:63.71–65.66], and 70.18% [95%CI:68.83–71.56] after excluding skin and cervical cancers. Skin and cervical cancers represented 61.24% of non-self-reported cancers. The overall PPV was 97.45% [95%CI:97.45–97.81], and 97.33% [95%CI:96.72–97.82] after the exclusion of skin and cervical cancers. Participants who did not self-report their cancer were more likely to be male, had longer time since diagnosis and lower educational level. Conclusion: Overall, the reports of cancer in Lifelines have a high positive predictive value and moderate sensitivity. One third of the cancers were not reported, mainly skin and cervical cancers. Male participants, those with a lower educational level and those with longer time since diagnosis were less likely to self-report a diagnosed cancer

Comparison of health behaviours between cancer survivors and the general population:a cross-sectional analysis of the Lifelines cohort

Purpose: To compare the differences in lifestyle behaviours between cancer survivors (CSs) and cancer-free participants in a large and representative population-based cohort. Methods: We included 115,257 adults from the Lifelines cohort. Cancer status was self-reported, and health behaviours were measured (e.g. body mass index [BMI]) or assessed by questionnaire (e.g. physical activity, smoking, alcohol consumption, sedentary behaviour and diet). The data were then categorised for logistic regression analysis, stratified and adjusted by sex and age (< 55 vs ≥ 55 years). Results: CSs (5473; 4.7%) were diagnosed 9 ± 8.5 years before data collection, were older (mean age 55.4 vs 44.4 years) and more often female (66.6% vs 33.4%) than the cancer-free participants. They were also more likely to be physically active and to have a better diet, and also less likely to be alcohol drinkers; but, were more likely to have a higher BMI, be former smokers and to be sedentary. After adjustment for sex and age, however, BMI was more likely to be normal, physical activity was more likely to be higher and smoking to be prevalent in CSs. Current smoking was also significantly higher among females and those aged < 55 years who were CSs than for those with no history of cancer. Conclusions: In this population-based cohort, CSs have health behaviour comparable to those without a cancer diagnosis. Implications for cancer survivors: Smoking cessation strategies should target all CSs, but efforts could yield greatest benefit if they target females and those younger than 55 years

Factors of physical activity among Chinese children and adolescents:A systematic review

Background: Lack of physical activity is a growing problem in China, due to the fast economic development and changing living environment over the past two decades. The aim of this review is to summarize the factors related to physical activity in Chinese children and adolescents during this distinct period of development. Methods: A systematic search was finished on Jan 10th, 2017, and identified 2200 hits through PubMed and Web of Science. English-language published studies were included if they reported statistical associations between factors and physical activity. Adapted criteria from the Strengthening The Reporting of OBservational studies in Epidemiology (STROBE) statement and evaluation of the quality of prognosis studies in systematic reviews (QUIPS) were used to assess the risk of bias of the included studies. Related factors that were reported in at least three studies were summarized separately for children and adolescents using a semi-quantitative method. Results: Forty two papers (published 2002-2016) were included. Most designs were cross-sectional (79%), and most studies used questionnaires to assess physical activity. Sample size was above 1000 in 18 papers (43%). Thirty seven studies (88%) showed acceptable quality by methodological quality assessment. Most studies reported a low level of physical activity. Boys were consistently more active than girls, the parental physical activity was positively associated with children and adolescents' physical activity, children in suburban/rural regions showed less activity than in urban regions, and, specifically in adolescents, self-efficacy was positively associated with physical activity. Family socioeconomic status and parental education were not associated with physical activity in children and adolescents. Conclusions: The studies included in this review were large but mostly of low quality in terms of study design (cross-sectional) and methods (questionnaires). Parental physical activity and self-efficacy are promising targets for future physical activity promotion programmes. The low level of physical activity raises concern, especially in suburban/rural regions. Future research is required to enhance our understanding of other influences, such as the physical environment, especially in early childhood

SORTA:a system for ontology-based re-coding and technical annotation of biomedical phenotype data

There is an urgent need to standardize the semantics of biomedical data values, such as phenotypes, to enable comparative and integrative analyses. However, it is unlikely that all studies will use the same data collection protocols. As a result, retrospective standardization is often required, which involves matching of original (unstructured or locally coded) data to widely used coding or ontology systems such as SNOMED CT (clinical terms), ICD-10 (International Classification of Disease) and HPO (Human Phenotype Ontology). This data curation process is usually a time-consuming process performed by a human expert. To help mechanize this process, we have developed SORTA, a computer-aided system for rapidly encoding free text or locally coded values to a formal coding system or ontology. SORTA matches original data values (uploaded in semicolon delimited format) to a target coding system (uploaded in Excel spreadsheet, OWL ontology web language or OBO open biomedical ontologies format). It then semi-automatically shortlists candidate codes for each data value using Lucene and n-gram based matching algorithms, and can also learn from matches chosen by human experts. We evaluated SORTA's applicability in two use cases. For the LifeLines biobank, we used SORTA to recode 90 000 free text values (including 5211 unique values) about physical exercise to MET (Metabolic Equivalent of Task) codes. For the CINEAS clinical symptom coding system, we used SORTA to map to HPO, enriching HPO when necessary (315 terms matched so far). Out of the shortlists at rank 1, we found a precision/recall of 0.97/0.98 in LifeLines and of 0.58/0.45 in CINEAS. More importantly, users found the tool both a major time saver and a quality improvement because SORTA reduced the chances of human mistakes. Thus, SORTA can dramatically ease data (re) coding tasks and we believe it will prove useful for many more projects

Parental physical activity is associated with objectively measured physical activity in young children in a sex-specific manner:The GECKO Drenthe cohort

Background: Physical activity (PA) is important in combating childhood obesity. Parents, and thus parental PA, could influence PA in young children. We examined whether the time spent at different intensities of PA and the type of parental PA are associated with the PA of children aged 4-7 years, and whether the associations between child-parent pairs were sex-specific. Methods: All the participants were recruited from the Groningen Expert Center for Kids with Obesity (GECKO) birth cohort (babies born between 1 April 2006 and 1 April 2007 in Drenthe province, the Netherlands) and were aged 4-7 years during measurement. PA in children was measured using the ActiGraph GT3X (worn at least 3 days, ≥10 h per day). PA in parents was assessed using the validated SQUASH questionnaire. Results: Of the N = 1146 children with valid ActiGraph data and 838 mothers and 814 fathers with valid questionnaire data, 623 child-parent pairs with complete data were analysed. More leisure time PA in mothers was associated with more time spent in moderate-to-vigorous PA (MVPA) in children (Spearman r = 0.079, P <.05). Maternal PA was significantly related to PA in girls, but not boys. More time spent in maternal vigorous PA, in sports activity, and leisure time PA, were all related to higher MVPA in girls (Spearman r = 0.159, r = 0.133 and r = 0.127 respectively, Pall <.05). In fathers, PA levels were predominantly related to PA in sons. High MVPA in fathers was also related to high MVPA in sons (r = 0.132, P < 0.5). Spending more time in light PA was related to more sedentary time and less time in MVPA in sons. Conclusions: Higher PA in mothers, for instance in leisure activities, is related to higher PA in daughters, and more active fathers are related to more active sons. To support PA in young children, interventions could focus on the PA of the parent of the same sex as the child. Special attention may be needed for families where the parents have sedentary jobs, as children from these families seem to adopt more sedentary behaviour