Éducation et prévention de l’obésité de l’enfant. bilan des études en population

The prevalences of overweight and obesity are increasing in France as well as in many countries around the world. Results of randomised controlled primary prevention studies in schools are summarized. They show the feasibility of improving school meals and energy expenditure during PE classes. However, the effect on overweight and obesity prevention are often modest. It is clear that the out-of-school life can totally compensate the effect of an intervention at school. Studies that have been able to modify the children's sedentary and active behaviours out of school have shown the most promising results. The National Nutrition and Health Plan in France comprises a set of actions targeting the whole population, from young children to the elderly, for several years. In that context, we may hope that the different actions undertaken in France including those at school will end with more favourable results.     

Rôle du préavis psychiatrique dans l’évaluation préopératoire des patients candidats à la chirurgie de l’obésité

The increase of obesity prevalence and severity, the failure of conservative treatment and the request for a long term efficient solution have given to surgery a rising role in the treatment of obesity. The psychiatric evaluation for bariatric surgery, the preparation and follow up of the patients are essential aims to reduce surgical risks and complications and improve the eating tolerance imposed by bariatric surgery.In this context the multidisciplinary team is very important, each complementary advice allowing the setting of strategies to better anticipate and manage post operative changes.The psychiatric evaluation includes the detection of formal contra-indications, the appreciation of relative indications and the assessment of eating disorders.     

Promouvoir l’activité physique, lutter contre la sédentarité et prévenir le surpoids chez l’adolescent, c’est possible : les leçons d’ICAPS

Based on a socioecological approach, the Intervention Centered on Adolescents’ Physical activity and Sedentary behavior (ICAPS), a four-year randomized and controlled trial has shown that prevention of sedentariness and of obesity is feasible in youth thanks the mobilization of several partners including actors in the domains of health, education, physical activity, transport and of community agencies in charge of recreational areas and transportation infrastructures. In this article, we present a synthesis of the key data demonstrating the efficacy of ICAPS at the end of the four years of intervention as well as preliminary results of the six-year follow-up study, i.e. two years after the end of the intervention. We discuss a few tracks on elements that may explain the effectiveness of the strategy implemented.     

Conception et évaluation d’une intervention brève « alimentation et prévention cardiovasculaire » en médecine de premier recours

The goal of our project was to assess acceptability and feasibility of a 5-step brief intervention (BI) on diet and coronary heart disease (CHD) prevention by general practitioners in a primary care setting. The intervention process and its acceptability by patients and physicians were assessed by standardised interviews and questionnaires, measuring the proportion of patients included, BI duration, perceived obstacles, usefulness and relevance of BI, patients’ knowledge and planned behavior change. Of 99 eligible patients, 76 (77 %) participated and 48 received the BI, which took 5–10 minutes in the consultation. Three of the five steps were usually (38 %) performed. The five physicians were interested and motivated but mentioned lack of time. Most patients (77 %) said they had learned something new about their diet in relation to CHD, and 64 % were able to express at least one dietary habit they planned to change. Ninety-eight percent considered it was their physician's role to discuss their diet to prevent CHD. However, BI's implementation proves difficult in physicians’ routine.     

Physiopathologie de l’insulinorésistance dans le muscle squelettique et implication des fonctions mitochondriales

In modern societies, decreased physical activity, nutritional transition and aging contribute to the increase in the prevalence of obesity and its associated pathologies (as cardiovascular diseases and type 2 diabetes). Obesity is tightly correlated with insulin resistance, which appears in the early stages of type 2 diabetes. As skeletal muscle is quantitatively the main tissue involved in glucose transport in response to insulin, muscle insulin resistance is a key step in the etiology of type 2 diabetes. Several alterations of skeletal muscle insulin signaling in various models of obesity or type 2 diabetes have been evidenced and numerous underlying mechanisms have been hypothesized. Among them, muscle lipotoxicity, obesity-induced adipose tissue inflammation and oxidative stress following excess of energetic substrates could be involved, independently or synergically, in the development of muscle insulin resistance. Moreover, mitochondrial alterations have been reported in the skeletal muscle of obese or diabetic patients and animals. This suggests that mitochondrion, through its capacity of regulating cellular fatty acids flux and redox state, may play a key role in obesity-induced skeletal muscle insulin resistance.     

Obésité sarcopénique et altérations du métabolisme protéique musculaire

The increasing prevalence of obesity among elderly people has led to the definition of the concept of sarcopenic obesity. This concept is defined as the potential to combine muscle metabolic changes associated with both aging and obesity. Several definitions have been proposed, but the absence of a consensus led to great variability in the prevalence of this phenomenon in literature. However, the proportion of the older obese population is not negligible, representing 5 to 15% of elderly people. The study of metabolic abnormalities associated with sarcopenic obesity is of importance, since these subjects are at increased risk of developing functional disability. However, very few studies evaluated the mechanisms involved in the cumulating and aggravating effect of obesity in the elderly, particularly at muscle level. Of note, significant alterations of muscle protein anabolism were observed in elderly people but also in obese subjects. Impairment in muscle protein metabolism, including protein synthesis rate, could be involved in the loss of functional capacity during sarcopenic obesity.     

Mesures objectives de l’environnement bâti et statut pondéral des enfants et adolescents : revue de la littérature

In the framework of the study of the Environmental links to physical activity, nutrition and health (ELIANE), we performed a systematic review of the associations between objective spatial measurements of the built environment and weight status in youth. Of the 25 identified papers, 18 reported at least one significant relationship, although only almost one-third of the associations tested were significant. Inverse relationships of weight with different walkability indices were the most consistent (7/9 papers). Weight was also positively related to spatial accessibility to convenience stores (3/6 papers), and inversely to the accessibility to recreational physical activity facilities (4/9 papers). Relationships with parks, other food retail outlets and restaurants were inconsistent. Reasons for such discrepant results are discussed. Better-built environment measures are needed. The challenge lies also in better understanding the complex pathways through which the built environment, the socioeconomic context, and the perception of their environment by the subjects impact childhood behaviors and weight status.     

Connaître les pièges du suivi après by-pass gastrique pour obésité

During the follow-up of obese patients operated for gastric surgery, practitioners must be vigilant for several reasons. The semiology of the surgical complications is often misleading. Physicians may consider that because of weight loss and comorbidities improvement, the patient is cured. Moreover, the positive situation created by weight loss leads the patient to minimize symptoms and difficulties. Several clinical situations require attention and rigorous evaluation. Abdominal pain should be a warning sign of surgical complications, requiring urgent response (intestinal obstruction, internal hernia, cholecystitis). Pain semiology can guide complementary investigations such as oesogastroduodenal fibroscopy useful to diagnose anastomotic ulcers occasionally resulting in anemia. Recurrent postprandial pain evokes an internal hernia, for which exploratory laparoscopy should be discussed. Faintness is particularly frequent after gastric bypass and most often associated with postprandial hypoglycemia. Practitioners should have a higher awareness of symptoms consistent with neuroglycopenia in patients with a history of bariatric surgery. First of all, uptake of hypoglycemic drugs and neurological and cardiological causes should be eliminated. Furthermore, in the presence of fasting neuroglycopenic signs, an insulinoma must be eliminated. In the presence of hypoglycemic faintness, dietary measures (fractionated meals, low glycemic index) are necessary but not always sufficient. Treatment (acarbose, calcium channel blockers, diazoxide or octreotide) could be discussed although their effectiveness is not clearly demonstrated. Occasionally, some teams suggest surgery of the gastric pouch or distal pancreatectomy. After gastric surgery, nutritional deficiencies are common (iron and vitamin D especially). Neurological complications are rare but potentially serious such as Gayet-Wernicke encephalopathy or neuropathy, most often related to deficiencies in vitamins B1, B12 or B6. Physicians must be vigilant in case of rapid weight loss, surgical complications, intercurrent diseases, vomiting or protein malnutrition. Recent appearance of neurological signs should be treated promptly without waiting for laboratory confirmation of vitamin deficiency. The infusion of glucose after surgery must always be accompanied by a parenteral supplementation of B1 vitamin. Finally, weight curve must be carefully monitored. An unusual weight loss leads to search intercurrent diseases such as surgical complications or neoplasia and psychological disturbance.     

Nutrition et prévention tertiaire des cancers. y a-t-il des recommandations ?

Despite their heterogeneity, numerous studies suggest that life style and diet might be involved in cancer recurrence. Data seems more robust in breast and colon cancer. Recently, two large randomized trials conducted in breast cancer patients confirmed the feasibility of dietary interventions after cancer treatment. Their methodology remains however somewhat flawed. Thus, because of poor level of evidence, it remains hazardous to recommend specific interventions in cancer survivors. Noteworthy, there is no evidence supporting the use of high-dose micronutrients in order to improve cancer outcomes. On the other hand, the benefits of weight control and regular physical activity are less debatable. No matter what, it would appear essential that we carry out clinical research with the aim of identifying sub-groups of patients the most likely to benefit from a given dietary intervention.     

Quelques aspects de la motivation à manger en fonction de l’index de masse corporelle (de la maigreur à l’obésité massive) dans un groupe de 2 509 adultes

This study examines how chronic dietary restraint, disinhibition, and hunger, as assessed by the Eating Inventory (also called the “Three Factor Eating Questionnaire”), vary over a broad range of Body Mass Index (BMI) values from leanness to massive obesity, in subjects with family obesity. EI factors were also studied as a function of personal weight history. Subjects were 2509 participants in a genetic study of obesity. BMIs ranged from 15 to 87kg/m². Multivariate analyses showed that restraint and disinhibition were significantly associated with the BMI in men, while only disinhibition was in women. Further analyses were performed after subdividing the population in 6 BMI groups. Disinhibition scores correlated strongly with hunger scores in both genders in all BMI categories; dietary restraint tended to correlate with the other two factors positively in leaner subjects, and negatively in highest BMI categories. The highest restraint scores were observed in nonobese adult women with previous obesity in childhood and/or adolescence, suggesting a beneficial influence of restraint on body weight loss. The role of behaviors associated with disinhibition in the development of body adiposity deserves further investigation.     

Prévention et prise en charge de la dénutrition dans les EHPAD

In order to identify best practices for undernutrition prevention and management in the 597 institutions for the dependent elderly in Pays de la Loire, two questionnaires were sent in early 2009. Three-quarters had a nutritional axis in their care project, 25% worked with a Diet and Nutrition Liaison Committee (CLAN), and 67% with dieticians; 70% had less than 25% of their staff recently trained to food-nutrition for the elderly. Two thirds were conducting detection of malnutrition at admission and during follow-up. There was enough time for meals in 60% cases, and 48% had all their residents who underwent a long overnight fast. Among beneficial environmental factors identified, the nutritional axis in the care project seemed to be a major determinant of food-nutrition practices. In conclusion, these results show the real structures involvement in this field in the region, but some practices must be further improved. Nutritional policies seem to be a major way to achieve.     

Alimentation, activité physique et surpoids chez des enfants de l’est Algérien

The prevalence of overweight and obesity were measured in a sample of 251 children aged 8 to 12 year in an urban area of the Eastern part of Algeria. IOTF references are used in order to define overweight and obesity.The overall prevalence of overweight and obesity is 21.5 %. 15.9 %. Overweight alone is found in 15.9% and obesity in 5,6 % of the children. Obese children consume less often a breakfast and less milk than that normal weight children and eat more often high fat, high carbohydrates foods. Mean caloric intakes are similar. Meals and snacking take often place while watching television. Energy percent derived from proteins but not their absolute amount and fat intakes are higher in overweight children. Most of the overweight children (78 %) do not practice any sport activity. Fat intake adjusted on energy intake is positively correlated with sport duration.This preliminary study suggest that childhood obesity is now a public health threat in Algeria.     

Lipides et inflammation postprandiale : impact du microbiote intestinal

Obesity and type 2 diabetes are associated with low-grade inflammatory tone. Growing evidence demonstrates that the gut microbiota is involved not only in the host metabolism but also in the pathogenesis of the low grade inflammation associated with obesity and type 2 diabetes. Among the mechanisms, dietary habits and more specifically the nutritional composition of the diet (lipids, non-digestible carbohydrates) have been shown to participate to the modulation of the composition and the activity of the gut microbiota. These questions and mechanisms will be discussed following experimental data.     

Les cellules endothéliales du tissu adipeux

The adipose tissue plays a major role in energy homeostasis through the storage and release of fatty acids as well as adipokine production. The endothelial cells of the adipose tissue vascular network constitute a barrier between the blood and the adipocyte compartments. They are key players in the metabolic status of the fat mass controlling the exchanges of nutrients, hormones, oxygen and immune-inflammatory cells. Recent data highlight the process of lipid handling at the endothelial cell surface and of the transendothelial transit of fatty acids. The extension of the vascular network and its functionality are necessary for the adipose tissue integrity. Insufficient oxygen supply generates hypoxic area within the tissue that favors metabolic abnormalities and the recruitment of immuno-inflammatory cells. The present review relates to the role of adipose tissue endothelial cells in the adipose tissue physiology. Their involvement and more particularly the role of accelerated ageing, in the link between obesity and associated metabolic and cardiovascular pathologies are described.