| Malnutrition is a gradual decline in the nutritional status, which in its more advanced stages leads to a decrease in functional capacity and to medical complications. Protein energy malnutrition (PEM) is defined as poor nutritional status due to inadequate nutrient intake.
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| Reduced food intake leads to reductive adaptation which includes a decrease in nutrient stores, changes in body composition and the more efficient use of fuels such as the use of ketone bodies by the brain (the metabolic changes in starvation are described in more detail in Chapter 20).
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| Malnutrition is one of the key problems faced by public health in the developing world and needs to be viewed from not only medical, but also social and economic perspective. Mortality in malnourished patients (BMI between 10 and 13) is four times higher compared to well-nourished ones. The effects of malnutrition are summarized in Table 21.6. Worldwide, malnutrition contributes to 54% of 11.6 million deaths annually among children below 5 years of age.
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| In the developed world, malnutrition is a problem in hospitalized patients who are unable to eat because of their disease such as, for instance, stroke or cancer. Gastrointestinal problems, particularly the colon pathology and coeliac disease (see case, Chapter 9), or post-operative conditions, are associated with specific nutritional problems. Malnutrition also affects a large group of elder individuals who might have problems with, for instance, access to food. In the UK, up to 40% of patients admitted to hospitals are undernourished. In addition to malnutrition, specific deficiencies such as those of vitamin D, iron, and vitamin C occur.
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Table 21-6.
The effects of protein-calorie malnutrition. |
| Body_ID: None |
| Effects of protein-calorie malnutrition |
| Body_ID: T021006.50 |
| Effects of protein-calorie malnutrition |
| Body_ID: T021006.100 |
| Decreased protein synthesis |
| Body_ID: T021006.150 |
| Decreased activity of Na+/K+ ATPase |
| Body_ID: T021006.200 |
Decreased glucose transport |
| Body_ID: T021006.250 |
| Fatty liver, liver necrosis, liver fibrosis |
| Body_ID: T021006.300 |
| Depression, apathy, mood changes |
| Body_ID: T021006.350 |
| Hypothermia |
| Body_ID: T021006.400 |
| Compromised ventilation |
| Body_ID: T021006.450 |
| Compromised immune system: impaired wound healing. |
| Body_ID: T021006.500 |
| Risk of wound breakdown |
| Body_ID: T021006.550 |
| Decreased cardiac output |
| Body_ID: T021006.600 |
| Decreased renal function |
| Body_ID: T021006.650 |
| Loss of muscle strength |
| Body_ID: T021006.700 |
| Anorexia |
| Body_ID: T021006.750 |
| Decreased mobility |
| Body_ID: T021006.800 |
| |
| Body_ID: T021006.850 |
Malnutrition affects multiple organs and systems.
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| page 307 |  | | page 308 |
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Table 21-7.
Classification of malnutrition. |
| Body_ID: None |
| Classification of malnutrition |
| Body_ID: T021007.50 |
| Moderate | Severe | Complicated |
| Body_ID: T021007.100 |
| Weight for height (% of median) 70-80 | <70 | <80 |
| Body_ID: T021007.150 |
| - or pitting oedema no | yes | yes |
| Body_ID: T021007.200 |
| - or mild upper arm circumference 110-125 | <110 mm | <110 mm |
| Body_ID: T021007.250 |
| Appetite, clinically well, alert yes | yes | no* |
| Body_ID: T021007.300 |
|
| Body_ID: T021007.350 |
|
| Body_ID: T021007.400 |
*Patients with complicated malnutrition may develop anorexia, high fever, anemia and dehydration.
Note that, in the classical classification of malnutrition, the presence of edema is also the main differentiating feature between marasmus and kwashiorkor.
After Collins S, Yates R. The need to update the classification of acute malnutrition Lancet 2003;362:249.
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| There are two types of protein-calorie malnutrition: marasmus and kwashiorkor
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| Marasmus results from a prolonged inadequate intake of calories and protein. It is a chronic condition, which develops over months or years. It is characterized by loss of muscle tissue and subcutaneous fat with the preservation of the synthesis of visceral proteins such as albumin. There is a clear loss of weight.
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| Kwashiorkor is a more acute form of undernutrition, which may also occur on the background of marasmus. It also develops because of inadequate nutrient intake after trauma or infection. In kwashiorkor, in contrast to marasmus, visceral tissues are not spared: the hallmark of kwashiorkor is oedema due to the low concentration of plasma albumin and the loss of oncotic pressure (Chapter 22). Such edema may mask the weight loss. Complications of kwashiorkor are dehydration, hypoglycemia, hypothermia, electrolyte disturbances and septicemia. These patients have impaired immunity and wound healing, and are prone to infection. The WHO classification of malnutrition is based on anthropometry and the presence of bilateral pitting edema. A classification has been proposed recently which distinguishes complicated from uncomplicated malnutrition (Table 21.7). Marasmus and kwashiorkor are the terms rarely used in the hospital practice in the developed countries: malnutrition and complicated malnutrition are probably more appropriate terms.
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| Inappropriate treatment of a malnourished person may lead to refeeding syndrome
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| AN OBESE MAN WITH TYPE 2 DIABETES, CORONARY DISEASE, AND ARTHRITIS |
| Mr K is a 55-year-old gentleman with type 2 diabetes and coronary disease. He gets angina on effort and also suffers from severe arthritic knee pain. When he initially presented to the outpatient clinic his weight was 140 kg and his height 1.80 m (BMI 43). Within a year he managed to lose 12 kg by dieting. Subsequently, he was prescribed a lipase inhibitor, which he tolerated well. However, his arthritis worsened and he was increasingly less able to exercise. As a result his weight increased again to 137 kg. He was referred to the surgeons and is now being considered for gastric banding surgery. |
| Comment. This patient illustrates multiple problems associated with obesity and in particular the way disease may interfere with weight reduction programs. Weight loss is, to a substantial extent, dependent on the level of exercise. This patient lost weight initially but the maintenance of lower body weight was compromised by decreased mobility caused by arthritis. |
| The inpatient treatment of malnutrition in the famine areas includes standard preparations such as the Formula 100 therapeutic milk (F100). F100 is a liquid diet with an energy content 100kcal/100 ml. It includes dried skimmed milk, oil, sugar and a mix of vitamins and minerals (without iron). In the areas of famine, community feeding programs use the
so-called life-sustaining general rations (at least 2100 kcal; 8786 kJ/day) containing grains, legumes, and vegetable oil. During the treatment of malnutrition, this needs to be combined with providing adequate water, sanitation, and basic health care.
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| It is important to take time to replete nutritionally a starved person. Too quick a replacement may be dangerous due to a major fluid shifts between intracellular and extracellular fluid. This is known as the refeeding syndrome, characterized by low concentrations of serum magnesium, phosphate and potassium (the latter because of the stimulation of insulin secretion). Also, if thiamin deficiency is present, carbohydrate feeding can precipitate the Wernicke-Korsakoff syndrome (see Chapter 10). Frequent simple meals at short intervals are recommended during famine relief and, in a hospital setting a gradual introduction of nutritional support and close monitoring are required.
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