L’obésité du sujet âgé

Our population is ageing, and obesity is increasing in the elderly. BMI value associated with the lowest relative mortality is slightly higher in older than in younger (between 25 and 32 kg/m²). Nevertheless, the combined effect of aging and obesity increases the risk of comorbidities, including type 2 diabetes mellitus, cardiovascular risk, respiratory insufficiency, obstructive sleep apneas, cancer, urinary incontinence and dementia. The medical consequences of obesity are alleviated by modest, achievable weight loss (5–10 kg) with an evidence-based maintenance strategy. A combination of exercise and modest calorie restriction appears to be the optimal method of reducing fat mass and preserving muscle mass. The clinical outcomes have been evaluated in diabetes mellitus and in cardiovascular diseases, showing favorable effects on the morbidity and probably on the mortality. Very-low-energy diets have to be avoided for elderly patients. The risk of muscle loss increases with the level of diet restriction. In older people, the risks of laparoscopic bariatric surgery are not higher than in younger but the benefits have not been evaluated. The sarcopenic obesity (excess in body fat and loss of muscle mass and function) burdens the functional consequences of obesity in older people. Since sarcopenia is frequent in the elderly, a screening should be done in obese patients for whom a restrictive diet is not recommended. In renal or cardiac insufficiency, only physical activity can be recommended. In elderly people, weight management interventions using moderate calorie restriction and physical activity exercise are recommended. Daily protein intake must be maintained. Health benefits and risks from long-term weight management in obese elderly have to be studied in randomized controlled studies.     

Dénutrition chez l’enfant et l’adolescent obèse

Recently, childhood obesity, defined by an excessive fat mass, has become a major public health problem due to its steady increased prevalence over the last thirty years and its long-term complications if it persists during adulthood. Although malnutrition is rare in obese children, this population is at risk for iron and vitamin deficiencies. Hypovitaminosis D affects more than one in three children and requires systematic supplementation per 100,000 IU of vitamin D every three months. Iron deficiency is common as described in the pediatric population and must be detected. Specific vitamin of group B deficiencies is also described but is more rare. In addition, with the emergence of bariatric surgery in teenagers with sleeve gastrectomy or gastric by-pass, the risk of malnutrition will increase throughout life, especially in the case of poor compliance with vitaminic supplements as observed in adults.     

Comment définir et diagnostiquer la dénutrition chez le sujet obèse ?

Undernutrition in the obese patient, like the non-obese patient, has numerous clinical consequences and leads to an increase in morbidity and mortality, but it is still underestimated. It is therefore imperative to prevent, detect and manage it as early as possible especially in patients at risk or weakened by a chronic disease. However, the definition and diagnostic criteria for undernutrition in non-obese adult subjects are flawed due to the clinical, morphological and biological characteristics associated with excessive adiposity. In an area where there is no consensus, the aim of this review is to highlight the difficulties in assessing undernutrition in this circumstance and to clarify the parameters of undernutrition assessment and their limits in the situation of obesity.     

Carence en vitamine C : y penser chez le sujet âgé fragile

Vitamin C deficiency remains a biological abnormality undervalued in the general population, especially among the frail elderly over 75 years. Clinical manifestations of moderate vitamin C deficiency remains non specific but can go, in case of deep and prolonged deficiency, to a hemorrhagic syndrome and dental manifestations such as gingival bleeding and loss of teeth. We are witnessing a re-emergence of scurvy among the elderly, who are a risky population. The treatment consists of taking vitamin C at a dose of 1 g/day for a period of 15 days.     

La nutrition dans le parcours de soins des personnes âgées

Among the structured care plans published by the High Authority of Health, the course dedicated specifically to the elderly aims at preventing the loss of autonomy. The approach promotes an action upstream to the risk of loss of autonomy, including the prevention of malnutrition. The personalized care plan concerns the elderly affected by one or several chronic diseases and/or frail. Frailty involves most of the time weight loss and a decrease of muscular function. “Key points and solutions” deal with the identification of and multimodal intervention in fragility syndrome and with the prevention of the avoidable hospital readmissions. The strategies of action include nutritional care and physical activity. Besides, the elderly may be concerned by several of the care plans developed for the chronic diseases. Some of these disease lead at any age to a risk of malnutrition (renal disease, Parkinson's disease, chronic bronchitis, cancer…). Others are more often associated with obesity in adults (diabetes, coronary disease, cardiac insufficiency…), but may be associated with malnutrition in the elderly. The specificities of the nutritional evaluation in the elderly and the efficacy of nutritional care would maybe deserve to appear more clearly in the courses of care concerning chronic diseases, which are increasingly prevalent in aging people; the objective is to maintain at best and as long as possible the quality of life for the aging people.     

Activité physique,nutrition et obésité

This review presents the various benefits of physical activity in obese patients and proposes a therapeutic strategy to include this important element in overall obesity management. Physical activity counseling includes structured endurance and resistance exercise training, promotion of lifestyle physical activity as well as limitation of sedentary behavior. The favorable effects of physical activity in obesity management are many but of varying importance. Weight maintenance after weight loss is considered the main benefit but requires higher volume of exercise than recommended for health maintenance in the general population. Other substantial benefits concern maintenance of body composition and improvement of obesity-related comorbidities, especially cardiometabolic complications. Programs and benefits of physical activity in the specific situation of weight loss after bariatric surgery need further research. Following a therapeutic education process aiming at sustained behavior modification, the goals for physical activity counseling need to be tailored to individual situations and barriers (physical/physiological, personal, environmental) should be carefully considered. Specific physical activity programs, when initiated in the health care sector, benefit from the input of physical activity educators. Maintenance of programs over time requires collaboration with stakeholders such as physical activity associations, sports clubs and obese patients organizations.     

Nutrition de l’obèse agressé

Over the past three decades the incidence of obesity showed a steady rise in developed countries. So, it is not surprising that obese patients constitute an increasing portion of patients admitted to the intensive care units. Critically ill obese patients are characterized by wide variations in their carbohydrate, lipid and amino acid/protein metabolism. Nutrition support in the critically ill patient is challenging but is even more difficult in a morbidly obese patient. Providing nutritional support for the critically ill obese patients represents a unique challenge to the medical team. Measurement of energy expenditure by indirect calorimetry has become the preferred method, however it is not always available and different equations could be used. Hypocaloric, high-protein nutritional support may be beneficial for net protein anabolism and better glycemic control.     

Nutrition de l’obèse agressé

The pandemic increase in obesity prevalence leads to a large increase in the number of obese patients admitted in the intensive care unit. The “obesity paradox” defines the protective effect of overweight and obesity (until 40 of body mass index) on intensive care unit mortality. In critically ill patients, obesity-related mortality is likely to be underestimated because of the use of non-suitable prognostic scores. During critical illness, the adipose tissue of obese patients stores lipids instead of utilizing them as energy source. It leads to the worsening of the muscle protein catabolism. The metabolic response to critical illness in obese patients may involve qualitative changes of the adipose tissue. Hyperglycemia is frequent and associated with patients’ poor prognosis making mandatory the glycemic control. Overnutrition must be avoided as it is deleterious. The main objective of nutritional support is to limit the malnutrition secondary to critical illness. In the critically ill obese patients, no method is validated for assessing nutritional status and protein–energy needs. The strategy of nutrition support is still largely debated, including the use of hypocaloric–hyperproteic feeding. The scarcity of scientific data makes urgent the biomedical research on the topic of the critically ill obese patients.