Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Lecture (3) Public Health Nutritional Disorders MALNUTRITION: pathological state resulting from a relative or absolute deficiency or excess of one or more essential nutrients; A clinically manifested or detected only by biochemical, anthropometric or physiological tests. The World Health Organization defines malnutrition as "the cellular imbalance between supply of nutrients & energy and the body's demand for them to ensure growth, maintenance, and specific functions”. The World Health Organization cites malnutrition as the greatest single threat to the world's public health and is associated with increases risk of disease and early death. Despite the fact that the world already produces enough food to feed everyone — 6 billion people — and could feed the double — 12 billion people, There were 925 million undernourished people in the world in 2010, an increase of 80 million since 1990. Nearly 17% of people in the developing world are undernourished. Under-and over-nutrition problems and diet-related chronic diseases account for more than half of the world's diseases and hundreds of millions of dollars in public expenditure. Forms of Malnutrition 1.Undernutrition: is depletion of energy (calories) resulting from insufficient food intake over an extended period of time. In extreme cases under-nutrition is called Starvation. 2.Overnutrition: is the pathological state resulting from the consumption of excessive quantity of food over an extended period of time. 3.Specific Deficiency: is the pathological state resulting from a deficiency of an individual nutrient such as vitamin A deficiency, iodine deficiency. 1 MANIFESTATIONS OF UNERNUTRITION 1.Under nutrition results in the loss of body weight. The loss of weight is a manifestation of energy depletion. 2.Malnutrition from any cause retards normal growth. Malnourished children grow up with worse health and lower educational achievements. 3.Decrease in immunity increases the susceptibility to infections such as T.B, which add to the morbidity and mortality. 4.Malnutrition is also associated with lowered vitality of the people leading to lowered productivity and reduced life expectancy. MANIFESTATIONS OF OVERNUTRITION In the more developed countries of the world, over nutrition is encountered much more frequently than under nutrition. The health hazards from over nutrition are: 1.Obesity 2.Diabetes 3.Hypertension 4.Cardiovascular diseases Nutrition assessment is the first step in developing a nutrition care plan and includes a clinical evaluation, anthropometric measurements, and Laboratory Assessment. CLINICAL EVALUATION • Medical and dietary history should include weight changes within 6 months, dietary intake changes, GI symptoms, functional capacity, and disease states. General clinical examination, with special attention to organs like hair, the mouth, gums, nails, skin, eyes, tongue, muscles, bones, & thyroid gland. 2 ANTHROPOMETRIC MEASUREMENTS •Anthropometric measurements are gross measurements of body cell mass used to evaluate LBM and fat stores. The most common measurements are weight, height, limb size (e.g., skin fold thickness and mid arm muscle, wrist, and waist circumferences). • Interpretation of actual body weight should consider ideal weight for height, usual body weight, fluid status, and age. Change over time can be calculated as percentage of usual body weight. Unintentional weight loss of more than 10% in less than 6 months correlates with poor clinical outcome in adults. • Ideal body weight provides a population reference standard against which the actual body weight can be compared to detect both under- and overnutrition (Table 1-1). See Table 1-2 for body weight equations. • The best indicator of adequate nutrition in children is appropriate growth. Additionally, the average weight gain for infants is 24 to 35 g/day for term infants and 10 to 25 g/day for preterm infants. • Body mass index (BMI) is another index of weight-for-height that is highly correlated with body fat. Interpretation of BMI should include consider ation of gender, frame size, and age. BMI values greater than 25 kg/m2 are indicative of overweight, and values less than 18.5 kg/m2 are indicative of undernutrition. BMI is calculated as follows: Body weight (kg)/[height (m)]2 3 TABLE 1-1 (( Evaluation of Body Weight)) Actual body weight (ABW) compared to ideal body weight (IBW) ABW <69% IBW Severe malnutrition ABW 70–79% IBW Moderate malnutrition ABW 80–89% IBW Mild malnutrition ABW 90–120% IBW Normal ABW >120% IBW Overweight Body mass index (BMI) (kg/m 2) Interpretation >18.5 undernutrition 19-25 Healthy 25-30 Overweight 30-40 Moderate obesity <40 Severe obesity TABLE 1-2 ( Body Weight Equations) Ideal body weight (IBW) Adult males = 50+(2.3×height in inches >5 feet) Adult females= 45.5+(2.3×height in inches >5 feet) Example/ Calculate IBW of man who is 64 inches tall and his actual weight 70 Kg ,assess the nutrition state ??? Answer/ IBW=50+(2.3kg ×4 inches) IBW=59.2kg so to assess the nutrition state Actual body weight (70kg) compared to ideal body weight(59.2kg) 70/59.2×100%=118% so this man has normal nutritional state Laboratory Assessment Advantages: It is useful in detecting early changes in body metabolism & nutrition before the appearance of overt clinical signs. It is precise, accurate and reproducible. 4 lab test include: Hemoglobin estimation is the most important test, & useful index of the overall state of nutrition. Beside anemia it also tells about protein & trace element nutrition. Stool examination for the presence of ova and/or intestinal parasites thyroid function tests levels of Calcium, Phosphate, Zinc and vitamins Enteral nutrition (EN) is the delivery of nutrients by tube or mouth into the GI tract. The goal of EN is to provide calories, macronutrients (e.g., carbohydrates, fats, and proteins), and micronutrients (e.g., electrolytes, trace elements, vitamins, and water) to patients who are unable to achieve these requirements from an oral diet. CLINICAL PRESENTATION AND INDICATIONS •EN is indicated for the patient who cannot or will not eat enough to meet nutritional requirements and who has a functioning GI tract. Additionally, a method of enteral access must be possible. Potential indications include neoplastic disease, organ failure, hypermetabolic states, and neurologic impairment. • The only absolute contraindications are mechanical obstruction and necrotizing enterocolitis. Conditions that challenge the success of EN include severe diarrhea, protracted vomiting, severe GI hemorrhage, and intestinal dysmotility. • EN has replaced parenteral nutrition (PN) as the preferred method for the feeding of critically ill patients requiring specialized nutrition support. Advantages of EN over PN include maintaining GI tract structure and function; fewer metabolic, infectious, and technical complications; and lower costs. 5 Parenteral nutrition (PN) provides macro- and micronutrients by central or peripheral venous access to meet specific nutritional requirements of the patient, promote positive clinical outcomes, and improve quality of life. Indications for Adult Parenteral Nutrition: 1. Inability to absorb nutrients via the GI tract because of one or more of the following: a. Massive small bowel resection. b. Intractable vomiting when adequate EN is not expected for 7–14 days. c. Severe diarrhea. d. Bowel obstruction. 2. Cancer: antineoplastic therapy, radiation chemoreceptor trigger zone and vomiting center) therapy (stimulate PN may be used in moderately to severely malnourished patients receiving active anticancer treatment who are not candidates for EN. 3. Pancreatitis: PN may be used in patients with severe pancreatitis with prolonged inadequate nutritional intake longer than 5–7 days who are not candidates for EN. PN should be used when EN exacerbates abdominal pain, ascites, or fistula output. 4. Critical care a. Organ failure (liver, renal, or respiratory): PN should be used in patients with moderate to severe catabolism when EN is contraindicated. b. Burns: PN should be used in those patients in whom EN is contraindicated or is unlikely to provide adequate nutritional requirements within 4–5 days. 5. Perioperative PN a. Preoperative: for 7–14 days for patients with moderate to severe malnutrition who are undergoing major GI surgery, if the operation can be safely postponed. 6 b. Postoperative: PN should be used in patients in whom EN is contraindicated or is unlikely to provide adequate nutritional requirements within 7–10 days. 6. Hyperemesis gravidarum: when EN is not tolerated. 7. Eating disorders: PN should be considered for patients with anorexia nervosa and severe malnutrition who are unable or unwilling to ingest adequate nutrition. Obesity is the state of excess body fat stores. ETIOLOGY •Genetic factors appear to be the primary determinants of obesity in some individuals. The specific gene that codes for obesity is unknown. • Environmental factors include reduced physical activity or work; abundant and readily available food supply; increased fat intake; increased consumption of refined simple sugars; and decreased ingestion of vegetables and fruits. • Excess caloric intake is a prerequisite to weight gain and obesity. • Many neurotransmitters and neuropeptides stimulate or depress the brain’s appetite network, impacting total caloric intake. • Weight gain can be caused by medical conditions (e.g., hypothyroidism, Cushing’s syndrome, hypothalamic lesion) or genetic syndromes (e.g., Prader-Willi’s syndrome). • Medications associated with weight gain include insulin, sulfonylureas, and thiazolidinediones for diabetes, some antidepressants, antipsychotics, and several anticonvulsants. DIAGNOSIS •Body mass index (BMI) and waist circumference (WC) are recognized, acceptable markers of excess body fat. • WC, the most practical method of characterizing central adiposity. 7 TREATMENT • Successful obesity treatment plans incorporate diet, exercise, behavior modification with or without pharmacologic therapy, and/or surgery . • The primary aim of behavior modification is to help patients choose lifestyles conducive to safe and sustained weight loss. Behavioral therapy is based on principles of human learning. • Many diets exist to aid weight loss. Regardless of the program, energy consumption must be less than energy expenditure. A reasonable goal is loss of 0.5 to 1 kg per week with a diet balanced in fat, carbohydrate, and protein intake. • Surgery, which reduces the stomach volume or absorptive surface of the alimentary tract, remains the most effective intervention for obesity. Although modern techniques are safer than older procedures and have an operative mortality of 1%, there are still many potential complications. Therefore, surgery should be reserved for those with BMI greater than 35 or 40 kg/m2 and significant co morbidity. PHARMACOLOGIC THERAPY • Orlistat(xenical) induces weight loss by lowering dietary fat absorption, and it also improves lipid profiles, glucose control, and other metabolic markers. Soft stools, abdominal pain or colic, flatulence, fecal urgency, and/or incontinence occur in 80% of individuals, are mild to moderate in severity, and improve after 1 to 2 months of therapy. Orlistat interferes with the absorption of fat-soluble vitamins and cyclosporine. • Sibutramine is more effective than placebo with the most significant weight loss during the first 6 months of use. Dry mouth, anorexia, insomnia, constipation, increased appetite, dizziness, and nausea occur two to three times more often than with placebo. Sibutramine should not be used in patients with coronary artery disease, stroke, congestive heart failure, arrhythmias, or monoamine oxidase inhibitor use. • Phentermine (30 mg in the morning or 8 mg before meals) has less powerful stimulant activity and lower abuse potential than amphetamines and was an effective adjunct in placebo-controlled studies. Adverse effects (e.g., increased blood pressure, palpitations, arrhythmias, 8 mydriasis, altered insulin or oral hypoglycemic requirements) and interactions with monoamine oxidase inhibitors have implications for patient selection. •Diethylpropion (25 mg before meals or 75 mg of extended-release formulation every morning) is more effective than placebo in achieving short-term weight loss. Diethylpropion is one of the safest noradrenergic appetite suppressants and can be used in patients with mild to moderate hypertension or angina, but it should not be used in patients with severe hypertension or significant cardiovascular disease. •Amphetamines should generally be avoided because of their powerful stimulant and addictive potential. • Herbal, natural, and food-supplement products are often used to promote weight loss . The FDA does not strictly regulate these prod- ucts, so the ingredients may be inactive and present in variable concentrations. After more than 800 reports of serious adverse events (e.g., seizures, stroke, and death) were attributed to ephedrine alkaloids, the FDA decided to exclude them from dietary supplements. 9