Individual and environmental factors associated with overweight among children in primary schools in Ghana

Philosophiae Doctor - PhDOverweight/obesity is a risk factor for non-communicable diseases such as cardiovascular diseases, diabetes, and some cancers. Obesity in childhood is known to predict later obesity in adolescence and adulthood. Understanding the factors associated with overweight/obesity among children may present an opportunity for timely and appropriate interventions in the African setting

Prevalence of obesity and overweight in African learners: A protocol for systematic review and meta-analysis

Introduction: Obesity and overweight are an emerging problem in Africa. Obese children are at increased risk of developing hypertension, high cholesterol, orthopaedic problems and type 2 diabetes as well as increased risk of adult obesity. Prevention of childhood overweight and obesity therefore needs high priority. The review approach is particularly useful in establishing whether research findings are consistent and can be generalised across populations and settings. This systematic review aims to assess the magnitude and distribution of overweight and obesity among primary school learners within populations in Africa. Methods and analysis: A comprehensive search of key bibliographic databases including MEDLINE (PubMed), MEDLINE (EbscoHost), CINAHL (EbscoHost), Academic Search Complete (EbscoHost) and ISI Web of Science (Science Citation Index) will be conducted for published literature. Grey literature will be also be obtained. Full-Text articles of eligible studies will be obtained and screened following predefined inclusion criteria. The quality of reporting as well as risk of bias of included studies will be assessed, data extracted and synthesised. The results will be summarised and presented by country and major regional groupings. Meta-Analysis will be conducted for identical variables across studies. This review will be reported following the MOOSE Guidelines for Meta-Analysis and Systematic Reviews of Observational Studies. Ethics and dissemination Ethics is not a requirement since no primary data will be collected. All data that will be presented in this review are based on published articles. The findings of this systematic review will be submitted for publication in peer-reviewed journals and disseminated in national and international conferences and also in policy documents to appropriate bodies for decision-making, where needed. It is expected that the findings will identify some research gaps for further studies.IS

School-based interventions targeting nutrition and physical activity, and body weight status of African children: A systematic review

Background: Overweight/obesity is an emerging health concern among African children. The aim of this study was to summarise available evidence from school-based interventions that focused on improving nutrition and physical activity knowledge, attitude, and behaviours, and weight status of children aged 6–15 years in the African context. Methods: Multiple databases were searched for studies evaluating school-based interventions of African origin that involved diet alone, physical activity alone, or multicomponent interventions, for at least 12 weeks in duration, reporting changes in either diet, physical activity, or body composition, and published between 1 January 2000 and 31 December 2018

Protocol for a scoping review of existing policies on the prevention and control of obesity across countries in Africa

INTRODUCTION: The obesity epidemic is a public health challenge for all, including low-income countries. The behavioural patterns known to contribute to the rise in obesity prevalence occur in an environmental context which is not conducive for healthy choices. A policy approach to obesity prevention constitutes a form of public intervention in that it extends beyond individuals to influence entire populations and is a mechanism for creating healthier environments. Little is known about obesity prevention policies in Africa. This scoping review seeks to examine the nature, extent and range of policies covering obesity prevention in Africa in order to assess how they align with international efforts in creating less obesogenic environments. This will help identify gaps in the approaches that are adopted in Africa. METHODS AND ANALYSIS: Using the Arksey and O’Malley’s scoping methodological framework as a guide, a comprehensive search of MEDLINE (PubMed), MEDLINE (EbscoHost) CINAHL (EbscoHost), Academic Search Complete (EbscoHost) and ISI Web of Science (Science Citation Index) databases will be carried out for peer reviewed journal articles related to obesity prevention policies using the African search filter. A grey literature search for policy documents and reports will also be conducted. There will be no language and date restrictions. Eligible policy documents and reports will be obtained and screened using the inclusion criteria. Data will be extracted and results analysed using descriptive numerical summary analysis and qualitative thematic analysis. ETHICS AND DISSEMINATION: No primary data will be collected since all data that will be presented in this review are based on published articles and publicly available documents, and therefore ethics committee approval is not a requirement. The findings of this systematic review will be presented at workshops and conferences; and will be submitted for publication in peer-reviewed journal. This will also form a chapter of a PhD thesis.IS

Diagnostic accuracy of body mass index in defining childhood obesity: Analysis of cross-sectional data from ghanaian children

Screening methods for childhood obesity are based largely on the published body mass index (BMI) criteria. Nonetheless, their accuracy in African children is largely unknown. The diagnostic accuracies of the World Health Organization (WHO), the Centers for Disease Control and Prevention (CDC), and the International Obesity Taskforce (IOTF) BMI-based criteria in defining obesity using deuterium dilution as a criterion method in a sample of Ghanaian children are presented. Methods: Data on anthropometric indices and percent body fat were collected from 183 children aged 8–11 years. The sensitivity, specificity, and predictive values were calculated. The overall performance of the BMI criteria was evaluated using the receiver operating characteristics area under the curve (AUC). Results: Overall sensitivity of WHO, CDC, and IOTF were 59.4% (40.6–76.3), 53.1% (34.7–70.9), and 46.9% (29.1–65.3) respectively. The overall specificity was high, ranging from 98.7% by WHO to 100.0% by IOTF. The AUC were 0.936 (0.865–1.000), 0.924 (0.852–0.995), and 0.945 (0.879–1.000) by the WHO, CDC, and IOTF criteria respectively for the overall sample. Prevalence of obesity by the WHO, CDC, IOTF, and deuterium oxide-derived percent body fat were 11.5%, 10.4%, 8.2%, and 17.5% respectively, with significant positive correlations between the BMI z-scores and percent body fat. Conclusions: The BMI-based criteria were largely specific but with moderate sensitivity in detecting excess body fat in Ghanaian children

Maternal and Infant Lipid-Based Nutritional Supplementation Increases Height of Ghanaian Children at 4–6 Years Only if the Mother Was Not Overweight Before Conception

Background Few studies have evaluated the long-term effects of nutritional supplementation during the first 1000 d of life. We previously reported that maternal and child lipid-based nutrient supplements (LNS) increased child length by 18 mo. Objective The aim of this study was to examine the effects of LNS on later growth and body composition at 4–6 y of age. Design This was a follow-up of children in the International Lipid-based Nutrient Supplements (iLiNS)-DYAD trial in Ghana. Women (n = 1320) at ≤20 weeks of gestation were randomly assigned to: 1) iron and folic acid during pregnancy and 200 mg calcium/d for 6 mo postpartum, 2) multiple micronutrients (1–2 RDA of 18 vitamins and minerals) during both periods, or 3) maternal LNS during both periods plus child LNS from 6 to 18 mo. At 4–6 y, we compared height, height-for-age z score (HAZ), and % body fat (deuterium dilution method) between the LNS group and the 2 non-LNS groups combined. Results Data were available for 961 children (76.5% of live births). There were no significant differences between LNS compared with non-LNS groups in height [106.7 compared with 106.3 cm (mean difference, MD, 0.36; P = 0.226)], HAZ [−0.49 compared with −0.57 (MD = 0.08; P = 0.226)], stunting (\u3c -2 SD) [6.5 compared with 6.3% (OR = 1.00; P = 0.993)], or % body fat [15.5 compared with 15.3% (MD = 0.16; P = 0.630)]. However, there was an interaction with maternal prepregnancy BMI (kg/m2) (P-interaction = 0.046 before correction for multiple testing): among children of women with BMI \u3c 25 , LNS children were taller than non-LNS children (+1.1 cm, P = 0.017), whereas there was no difference among children of women with BMI ≥ 25 (+0.1 cm; P = 0.874). Conclusions There was no overall effect of LNS on height at 4–6 y in this cohort, which had a low stunting rate, but height was greater in the LNS group among children of nonoverweight/obese women. There was no adverse impact of LNS on body composition. This trial was registered at clinicaltrials.gov as NCT00970866

Body mass index vs deuterium dilution method for establishing childhood obesity prevalence, Ghana, Kenya, Mauritius, Morocco, Namibia, Senegal, Tunisia and United Republic of Tanzania

Objective -- To compare the World Health Organization (WHO) body mass index (BMI)-for-age definition of obesity against measured body fatness in African children. Methods -- In a prospective multicentre study over 2013 to 2017, we recruited 1516 participants aged 8 to 11 years old from urban areas of eight countries (Ghana, Kenya, Mauritius, Morocco, Namibia, Senegal, Tunisia and United Republic of Tanzania). We measured height and weight and calculated BMI-for-age using WHO standards. We measured body fatness using the deuterium dilution method and defined excessive body fat percentage as > 25% in boys and > 30% in girls. We calculated the sensitivity and specificity of BMI z-score > +2.00 standard deviations (SD) and used receiver operating characteristic analysis and the Youden index to determine the optimal BMI z-score cut-off for classifying excessive fatness. Findings -- The prevalence of excessive fatness was over three times higher than BMI-for-age-defined obesity: 29.1% (95% CI: 26.8 to 31.4; 441 children) versus 8.8% (95% CI: 7.5 to 10.4; 134 children). The sensitivity of BMI z-score > +2.00 SD was low (29.7%, 95% CI: 25.5 to 34.2) and specificity was high (99.7%, 95% CI: 99.2 to 99.9). The receiver operating characteristic analysis found that a BMI z-score +0.58 SD would optimize sensitivity, and at this cut-off the area under the curve was 0.86, sensitivity 71.9% (95% CI: 67.4 to 76.0) and specificity 91.1% (95% CI: 89.2 to 92.7). Conclusion -- While BMI remains a practical tool for obesity surveillance, it underestimates excessive fatness and this should be considered when planning future African responses to the childhood obesity pandemic

A Scoping Review of Policies Related to the Prevention and Control of Overweight and Obesity in Africa

To address the issue of obesity, the World Health Organization (WHO) recommends a set of comprehensive programmes aimed at changing the obesogenic environments to provide opportunities for healthy food options and increased physical activity in the school, home, and at the population level. The objectives of this study were to examine the nature and range of policies related to overweight and obesity prevention in Africa, and to assess how they align with international guidelines. An existing methodological framework was adapted for this scoping review. A search of publicly available national documents on overweight/obesity, general health, and non-communicable diseases (NCDs) was undertaken from relevant websites, including WHO, ministries, and Google Scholar. Additional requests were sent to key contacts at relevant ministries about existing policy documents. The documents were reviewed, and the policies were categorised, using the Analysis Grid for Environments Linked to Obesity (ANGELO) framework. The framework categorises the environmental drivers of obesity into four domains (physical, economic, legislative, and socio-cultural) and two scales: macro (national, regional, sectors, food industries, media, etc.) and micro (household, institutional, and community). This review included documents from 41 African countries. The policy initiatives to prevent overweight/obesity target the school, family and community settings, and macro environments, and broadly align with global recommendations. The NCD documents were in the majority, with only two on obesity. The majority of the documents detailed strategies and key interventions on unhealthy diets and physical inactivity. The physical, legislative, and sociocultural domains were largely featured, with less emphasis on the economic domain. Additionally, nutrition- and diet-related policies were in the majority. Overlaps and interactions of policies were observed in the application of the ANGELO framework. This study has provided information on national policies and programmes in Africa and can be useful as a first point of call for policymakers. The overlapping and interaction in the initiatives demonstrate the importance of multi-sectoral partnerships in providing supportive environments for healthy behaviours

Diagnostic Accuracy of Body Mass Index in Defining Childhood Obesity: Analysis of Cross-Sectional Data from Ghanaian Children

Background: Screening methods for childhood obesity are based largely on the published body mass index (BMI) criteria. Nonetheless, their accuracy in African children is largely unknown. The diagnostic accuracies of the World Health Organization (WHO), the Centers for Disease Control and Prevention (CDC), and the International Obesity Taskforce (IOTF) BMI-based criteria in defining obesity using deuterium dilution as a criterion method in a sample of Ghanaian children are presented. Methods: Data on anthropometric indices and percent body fat were collected from 183 children aged 8–11 years. The sensitivity, specificity, and predictive values were calculated. The overall performance of the BMI criteria was evaluated using the receiver operating characteristics area under the curve (AUC). Results: Overall sensitivity of WHO, CDC, and IOTF were 59.4% (40.6–76.3), 53.1% (34.7–70.9), and 46.9% (29.1–65.3) respectively. The overall specificity was high, ranging from 98.7% by WHO to 100.0% by IOTF. The AUC were 0.936 (0.865–1.000), 0.924 (0.852–0.995), and 0.945 (0.879–1.000) by the WHO, CDC, and IOTF criteria respectively for the overall sample. Prevalence of obesity by the WHO, CDC, IOTF, and deuterium oxide-derived percent body fat were 11.5%, 10.4%, 8.2%, and 17.5% respectively, with significant positive correlations between the BMI z-scores and percent body fat. Conclusions: The BMI-based criteria were largely specific but with moderate sensitivity in detecting excess body fat in Ghanaian children. To improve diagnostic accuracy, direct measurement of body fat and other health risk factors should be considered in addition to BMI