Blood pressure and its correlates in children and adolescents in urban Nigeria

Background: A substantial increase in the incidence of chronic non-communicable diseases (NCDs) and a decline in communicable diseases and poverty-related diseases are occurring in developing countries (including Nigeria) as a result of an epidemiological transition. Given the burden and poor outcomes of NCDs related to hypertension or high blood pressure (BP) in adulthood, there is an urgent need for the identification of high risk individuals in early life. High BP has already been reported amongst young people worldwide, including Nigeria. High BP in childhood is predictive of high BP in adulthood. There is very little information available on the distribution of blood pressure in children and adolescents, and the factors which determine its distribution in Nigeria. Objectives: To determine the association between: socio-economic characteristics and blood pressure, pubertal maturation status and blood pressure, and anthropometric measures of adiposity and blood pressure in children and adolescents in Nigeria; and also to determine the overall prevalence of hypertension in the population of secondary school aged children and adolescents in Nigeria. Methods: A school-based stratified randomised cross-sectional survey of students aged 11 to 18 years was carried out in the urban area of Lagos, Nigeria. Blood pressure, body weight, height and waist measurements of the participants were obtained. A self-complete validated questionnaire was used to obtain sociodemographic information, health-related information, socio-economic characteristics (including living circumstances and parent/carer education level) and pubertal maturation status of the participants. Data analysis was carried out using descriptive statistics and multiple regression analysis. Results: 1086 students (538 males and 548 females) participated in the study, giving a total response rate of 90.5%. The overall mean systolic and diastolic blood pressure was 105.23±12.63mmHg and 57.87±8.09mmHg, respectively. The overall prevalence of hypertension was 2.5%. Socio-economic characteristics, pubertal maturation status, body mass index and waist circumference were statistically significantly associated with systolic and diastolic blood pressure (p<0.05). Conclusion: This study suggests that the epidemiological transition exists and is having measurable effects in school children in Nigeria. The findings highlight the presence of hypertension, and also the need for investigation of factors associated with blood pressure in children and adolescents so as to guide health policy, public health preventive interventions and health practice for child and adolescent hypertension. This study has long term implications for an extra burden of chronic non-communicable diseases related to hypertension in Nigeria

Type 2 diabetes mellitus in transitional Thailand:incidence, risk factors, mediators, and implications

Background Economic growth in Asia is changing population health profiles. Family structures, environments, occupations, education, and health behaviours have also changed and science-based health services have evolved. As part of this ‘health-risk transition’, noncommunicable diseases including type 2 diabetes mellitus (T2DM) have emerged. While the major causes of the diabetes epidemic in western, high-income countries are well documented, little is known of T2DM in developing Asia. The knowledge gap includes Thailand, which needs to identify local factors driving its T2DM epidemic. Aim This thesis aims to better understand the epidemiology of T2DM emerging in Southeast Asia. Methods Participants were from the Thai Cohort Study (TCS) of the health-risk transition. They were distance-learning adult students living all over Thailand, enrolled at Sukhothai Thammithirat Open University, and surveyed in 2005, 2009, and 2013 using mailed questionnaires that covered socio-demographic characteristics, lifestyle behaviours and self-reported health outcomes. In addition to these data, physician telephone interviews were conducted to validate self-reported questionnaire responses (2015); and a dietary survey was conducted to assess transitional dietary patterns (2015). Multiple logistic regression was used to calculate odds ratios and 95% confidence intervals (CIs) for longitudinal associations between exposures of interest and T2DM. Non-linear associations of body mass index (BMI) and T2DM were modelled using restricted cubic splines. Counterfactual mediation analysis explored sugary drink linkage to T2DM. Population attributable fractions and potential impact fractions were calculated. Principal component analysis identified dietary patterns and multivariable linear regression produced standardized coefficients and 95% CIs for associations between socio-demographic measures and dietary pattern scores. Results Physician telephone interviews of a cohort sample demonstrated high validity of questionnaire self-reported doctor diagnosed T2DM suggesting that self-reported doctor diagnosed T2DM is a feasible and acceptable method for assessing diabetes in epidemiological studies. Overall eight-year T2DM incidence was 177 per 10 000 (95% CI 164-190) with higher incidence in men. For both sexes, factors most strongly associated with T2DM risk were greater age and BMI. Two-thirds of all T2DM cases could be attributed to overweight and obesity. T2DM risk increased at BMI levels <23kg/m2. The increasing T2DM risk associated with body size became statistically significant at a BMI of 22 kg/m2 and 20 kg/m2 in men and women, respectively. For both sexes, living in urban areas increased T2DM and risk of consuming unhealthy dietary patterns, while a higher income associated with healthy dietary patterns. In Thai men, smoking and alcohol consumption increased T2DM risk. In women, sugary-drink consumption increased T2DM risk, of which 23% was mediated through obesity. In men, income and education were associated with increased T2DM risk. In women, education protected against unhealthy dietary intake. Overall, women tended to have safer behaviours (e.g. low prevalence of smoking and alcohol consumption) and better outcomes (e.g. lower prevalence of obesity and lower rates of T2DM). Conclusions Findings from young to middle-aged, educated Thai adults nationwide show that selfreport of incident T2DM is a valid method for assessing diabetes in epidemiological studies, T2DM incidence in Thailand is high, and accompanying lifestyle and sociodemographic transitions are driving the T2DM epidemic. Thai men are likely to be in the middle stages of the health-risk transition while women are more advanced. Health-risks for T2DM are changing substantially and could be modified. These risks need to be targeted to prevent and control diabetes in Thailand

Adult Changes in Weight and Physical Activity in Association with the Risk of Pancreatic Cancer: In the Vital Cohort

Significance. Pancreatic cancer is the fourth most common cancer-related death in the United States (U.S.); by 2030 this lethal disease is projected to be the second leading cause of cancer-related mortality. Thus, identifying modifiable risk factors for pancreatic cancer is of public health importance. Innovation. Two modifiable factors that impact pancreatic cancer are obesity and, perhaps, physical activity. Obesity is among the few risk factors that have been consistently associated with pancreatic cancer incidence, whereas the association with physical activity is inconsistent. However, whether age-specific exposures, or adult changes in exposure, are associated with pancreatic cancer is unclear for both exposures. Identification of age-specific risk factors, or adult changes in exposure, could lead to age-specific targeted prevention strategies. Dissertation Goals. My hypothesis was that age-specific weight and physical activity, and perhaps adult changes, may modulate pancreatic cancer risk. These exposures could plausibly act through several biologic mechanisms, including influencing circulating endogenous hormones, which may in turn impact pancreatic carcinogenesis. Thus, my objectives were to prospectively examine the associations of age-specific weight and physical activity, and adult changes, with pancreatic cancer risk. Methods. I used the National Cancer Institute-funded VITamins And Lifestyle (VITAL) study. This cohort of ~77,000 men and women in Washington state was recruited in 2000-2002, when participants were aged 55-76 years. Data collection included assessment of baseline, age-specific, and changes in adult weight and physical activity. Incident pancreatic cancer events (n=280) were identified through linkage to state and national registries after ~10 years of follow-up. Multi-variable Cox proportional hazards models were used to obtain estimates for the pancreatic cancer risk associations. Results. Pancreatic cancer risk was reduced by ~30-40% in association with adult physical activity undertaken in the 10 years prior to study recruitment, and with physical activity undertaken most days of the week during mid-life. In addition, mid-life adult obesity and weight gain, were associated with ~30-80% elevation in pancreatic cancer risk. Study Impact. If my results are replicated, targeting middle-aged adult Americans to engage in physical activity most days of the week, and avoid weight gain may be possible risk reduction strategies for this lethal cancer.Doctor of Philosoph

Dietary intake and nutritional status in Switzerland: a population perspective

Nutrition is a major modifiable determinant of health. National nutrition surveys are essential tools to monitor the population nutritional status and guide nutrition policies. Switzerland conducted its first national survey, menuCH, in 2014-2015. A total of 2 086 Swiss residents aged 18 to 75 years old were interviewed and their diet assessed using two 24-hour dietary recalls. This thesis aimed at 1) describing dietary intake of Swiss adult population using menuCH data, and 2) developing recommendations for the next national nutrition surveys and future nutrition policies. menuCH data indicated that the vast majority of the Swiss adult population poorly adhered to the national dietary guidelines. The population consumed insufficient plant-based products, and excessive ultra-processed and/or animal-based foods. Moreover, food consumption patterns substantially differed between the German, French and Italian-speaking parts of Switzerland. Finally, we showed that regularly consuming a breakfast rich in fruit, unsweetened cereal flakes, nuts and yogurt was associated with reduced abdominal obesity. Since menuCH did not survey children nor collect bio-samples, we tested child-specific dietary assessment methods and evaluated acceptability of bio-sample collection in a feasibility study to prepare the next national nutrition survey. We recruited a population-based sample of 53 children aged 3 to 17 years in Lausanne. The developed dietary assessment tools (e.g., 24-hour food diary, food questionnaire) were well accepted by participants and their caregiver(s). Compliance with the collection of spot urine, venous and capillary blood, and toenails was high in the different age groups. As shown above, dietary behaviours in Switzerland are not optimal. Classically, public health can propose two types of interventions to improve the situation: 1) provide information to encourage behavioural modifications (individual level), or 2) change the environment to reduce exposition (population level). I wrote an essay about a novel instrument designed to improve diet, i.e., precision nutrition. I concluded that providing personalized advice at a large scale via smartphones (individual level) might have a limited effect on dietary behaviours and obesity, if environments promoting unhealthy food are not modified in parallel (population level). We have shown that Switzerland needs public health interventions to improve dietary behaviours. We suggest that these interventions target in priority the food environments to facilitate access to healthy foods. Furthermore, the next national nutrition surveys should include children, strengthen dietary assessment methods, and collect bio-samples for relying on objective nutritional biomarkers. We believe that this will improve the assessment of dietary intake and nutritional status at both individual and population levels to further fine-tune national dietary guidelines and guide future nutrition policies

Dietary intake and overweight in childhood cancer during treatment and survivorship

Unhealthy nutrition and overweight may increase the risk for chronic health problems after childhood cancer treatment. It is therefore important to get a better understanding of the dietary intake of survivors and the personal and clinical characteristics related to adherence to dietary recommendations. Additionally, it is key to determine risk factors related to weight gain during and after treatment, e.g. type of cancer, treatment, age, gender etc. Our research is based on several sources of information. As part of the “Swiss Childhood Cancer Survivor Study” project, we sent two questionnaires. Childhood cancer survivors who survived at least 5 years filled in the first questionnaire. This questionnaire assessed adherence to dietary recommendations, and height and weight to calculate body mass index. The second questionnaire was a newly developed follow-up questionnaire completed by 1578 survivors, which assessed dietary intake in detail. Next, we measured several times height and weight of childhood cancer patients during treatment. Finally, we collected urine spot samples from 125 survivors and patients to compare them with detailed dietary intake information. For this last step, the analyses are ongoing. Analyses on all these sources of information allowed us to make the following observations: Only 43% of the survivors met the national recommended dietary intakes for meat, 34% for fruit, 30% for fish, 18% for dairy products, 11% for vegetables, and 7% for combined fruit and vegetables. Results were similar for siblings and the general population. Adherence was not better for those survivors with high cardiovascular risks. In all groups, characteristics related to dietary adherence were similar. After treatment, the prevalence of and risk factors for being overweight were the same for survivors and their peers. But, survivors treated with head radiation therapy of 20 gray or more were more often overweight after treatment. Glucocorticoid chemotherapy seemed to have no impact on overweight in the long term. During treatment, being a boy and having been diagnosed with a specific type of leukemia (acute lymphoblastic leukemia, ALL) or lymphoma were risk factors for weight gain. Children affected by other types of cancer tended to lose initially weight before gaining weight during the second half of treatment. Based on these results, we suggest that prevention methods for unhealthy diet and overweight can be similar for survivors as for the general population. An important exception are survivors treated with cranial radiotherapy of 20 gray or more who may need extra attention during follow-up care. Besides, patients diagnosed with ALL or lymphoma might benefit from early lifestyle interventions. -- Une mauvaise alimentation et un surpoids augmentent le risque de problèmes de santé chroniques après un traitement contre le cancer chez les enfants. Il est donc important de mieux comprendre l’apport alimentaire des survivants et les caractéristiques personnelles et cliniques liées à l'observance des recommandations alimentaires. Il est également important de déterminer quels sont les facteurs qui peuvent provoquer une prise de poids durant et après le traitement, p.ex. type de cancer, de traitements, âge, sexe de l’enfant, etc. Notre recherche se base sur plusieurs sources d’information. Dans le cadre du projet ‘Swiss Childhood Cancer Survivor Study’, nous avons envoyé deux questionnaires aux survivants d’un cancer durant l’enfance. Les anciens patients qui ont survécu au moins 5 ans ont rempli le premier questionnaire. Ce questionnaire a évalué l'observance des recommandations alimentaires, la taille et le poids pour calculer l'indice de masse corporelle (IMC). Le deuxième questionnaire était un nouveau questionnaire de suivi rempli par 1578 survivants, qui a évalué l'apport alimentaire en détail. Nous avons également relevé la taille et le poids des enfants à plusieurs reprises durant le traitement. Finalement, nous avons collecté des échantillons d'urine de 125 survivants et patients afin de les comparer aux informations détaillées sur l'apport alimentaire. Les analyses sont encore en cours pour cette dernière étape. L’analyse de toutes ces informations nous ont permis de faire les observations suivantes: Comparé aux lignes directrices nationales, seulement 43% des survivants respectaient les apports nutritionnels recommandés pour la viande, 34% pour les fruits, 30% pour le poisson, 18% pour les produits laitiers, 11% pour les légumes et 7% pour les fruits et légumes combinés. Les résultats étaient similaires pour les frères et sœurs et dans la population générale. Cela est également le cas pour les survivants ayant un risque cardiovasculaire élevé. Les caractéristiques liées à l'observance des recommandations alimentaires étaient semblables dans tous les groupes. Après le traitement, la prévalence et les facteurs de risque d'être en surpoids étaient les mêmes chez les survivants et leurs pairs. Mais les survivants traités avec une radiothérapie de la tête de 20 grays ou plus étaient plus souvent en surpoids après le traitement. La chimiothérapie aux glucocorticoïde semble n’avoir aucun impact sur le surpoids à long terme. Durant le traitement, le fait d'être un garçon et d'avoir été diagnostiqué avec un type spécifique de leucémie (la leucémie lymphoblastique aiguë, LLA) ou avec un lymphome, était un facteur de risque de prise de poids. Les enfants touchés par d'autres types de cancer avaient tendance à perdre du poids avant de prendre du poids pendant la seconde moitié du traitement. Sur la base de ces résultats, nous suggérons que les mesures de prévention contre une mauvaise alimentation et le surpoids peuvent être similaires pour les survivants comme pour la population générale. Une attention particulière doit être donnée durant les soins de suivi aux survivants traités par une radiothérapie de plus de 20 grays à la tête. De plus, les patients diagnostiqués avec une LLA ou un lymphome pourraient bénéficier d'interventions précoces de modification du style de vie