Malnutrition is an acute problem of the 21st century

Malnutrition is one of the forms of eating disorders. Inadequate nutrition can result from inadequate nutrient intake, malabsorption, impaired metabolism, nutritional loss with diarrhea, or with increased food demand (as is the case with cancer or infection).

Insufficient nutrition progresses gradually; usually each stage takes a long time to develop. First, the levels of nutrients in the blood and tissues change, then intracellular changes occur in the biochemical functions and structure. Eventually, signs and symptoms appear.

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Risk factors for malnutrition

Inadequate nutrition is associated with many disorders and circumstances, including poverty and social disasters. The risk of its occurrence is also greater in certain periods of time (in infancy, early childhood, pubertal period, during pregnancy, breast-feeding, in senile age).

Infancy and childhood. Infants and children are particularly susceptible to malnutrition because of their high energy needs and the necessary nutrients. With vitamin K deficiency, newborns can develop hemorrhagic disease of newborns, a life-threatening disorder. In infants fed only breast milk may develop a deficiency of vitamin B ₁₂, if the mother - vegan. Inadequately and inadequately fed babies and children are at risk of developing protein-energy deficiency, iron deficiency, folic acid, vitamins A and C, copper and zinc. During the pubertal period, the need for food increases because the growth rate of the whole organism is accelerating. The malnutrition in girls and young girls can be due to the characteristic neurogenic anorexia.

Pregnancy and lactation. Nutrient requirements increase during pregnancy and lactation. During pregnancy, there may be deviations from a normal diet, including perverted appetite (consumption of non-nutritive substances such as clay and activated carbon). Iron deficiency anemia is quite common, as is folate deficiency anemia, especially among women who have taken oral contraceptives.

Old age. Aging - even when the disease or nutritional deficiency is absent - leads to sarcopenia (progressive loss of muscle mass), which begins after 40 years and is ultimately expressed in the loss of approximately 10 kg (22 pounds) of muscle mass in men and 5 kg ( 11 pounds) in women. The reasons for this are a reduction in physical activity and food intake and an increase in the level of cytokines (especially interleukin-6). In men, the cause of sarcopenia is also a decrease in the level of androgens. With aging, the intensity of the basal metabolism decreases (mainly because of the decrease in lean body mass), the total body weight, height, skeleton mass and the average fat mass (in percentage of body weight) is approximately 20-30% in men and 27 -40% for women.

Since 20 years and up to 80, food intake, especially in men, is declining. Anorexia due to the very process of aging has many reasons: the adaptive relaxation of the bottom of the stomach decreases, the secretion and activity of cholecystokinin increases, which causes a feeling of saturation, and the release of leptin (anorectic hormone produced by adipocytes) increases. Reduced sense of smell and taste reduce the pleasure of eating, but usually only slightly reduce the amount of food consumed. Anorexia may have other causes (eg, loneliness, inability to buy food and cook food, dementia, some chronic disorders, use of certain drugs). A typical cause of malnutrition is depression. Sometimes food is prevented by neurogenic anorexia, paranoia or manic conditions. Dental problems limit the ability to chew and subsequently digest and assimilate food. A common cause is difficulty with swallowing (eg, due to seizures, strokes, other neurological disorders, esophageal candidiasis or xerostomia). Poverty or functional disorders limit the availability of nutrient intake.

Those who are placed in homes for the elderly are especially at risk of developing a protein-energy deficiency syndrome (BEN). They are often disoriented and unable to express that they are hungry or which foods they prefer. They may not be physically able to eat their own. Chewing or swallowing from them can be very slow, and for another person it becomes tedious to feed them with enough food. Insufficient intake and reduced absorption of vitamin D, as well as insufficient exposure to the sun lead to osteomalacia.

Various disorders and medical procedures. Diabetes, some chronic gastrointestinal disorders, intestinal resections, some other surgical interventions on the gastrointestinal tract lead to a violation of absorption of fat-soluble vitamins, vitamin B, calcium and iron. Gluten enteropathy, pancreatic insufficiency or other disorders can lead to malabsorption. Reduced absorption can contribute to iron deficiency and osteoporosis. Liver disorders weaken the accumulation of vitamins A and B and interfere with the metabolism of protein and energy sources. Renal insufficiency is a predisposing factor for deficiency of protein, iron and vitamin D. Consumption of inadequate amounts of food can be the result of anorexia in cancer patients, depression, AIDS. Infections, trauma, hyperthyroidism, extensive burns and prolonged fever increase metabolic needs.

Vegetarian diets. Deficiency of iron can occur in "egg-milk" vegetarians (although such a diet can be a guarantee of good health). Vegans may develop a deficiency of vitamin B ₁₂ unless they consume yeast extracts or food products, fermented in the Asian style. They also reduced the intake of calcium, iron, zinc. Only a fruit diet is not recommended, because it is deficient in protein, Na and many trace elements.

Newfangled diets. Some fashionable diets lead to a deficiency of vitamins, minerals and protein, cardiac, renal, metabolic disorders and sometimes death. Very low-calorie diets (<400 kcal / day) can not maintain health for a long time.

Medicines and nutritional supplements. Many drugs (eg, appetite suppressant, digoxin) reduce appetite, others worsen nutrient absorption or metabolism. Some drugs (for example, appetite stimulants) have catabolic effects. Certain drugs can weaken the absorption of many nutrients, for example, anticonvulsants can weaken the absorption of vitamins.

Alcohol or drug dependence. Patients with alcohol or drug dependence may neglect their nutritional needs. Absorption and metabolism of nutrients can also be weakened. "Intravenous" drug addicts usually become emaciated, as do alcoholics who consume more than one liter of spirits per day. Alcoholism can cause a deficiency of magnesium, zinc and certain vitamins, including thiamine.

Symptoms of malnutrition

Symptoms vary depending on the cause and type of malnutrition.

The diagnosis is based on the results of both medical history and diet, objective examination, body structure analysis and elective laboratory studies.

Anamnesis. Anamnesis should include questions about food intake, recent changes in weight and risk factors for malnutrition, including the use of drugs and alcohol. Unintentional loss of more than 10% of normal weight for three months indicates a high probability of malnutrition. A social anamnesis should include questions about whether money is available for food and whether the patient can buy it and cook it.

When examining a patient for organs and systems, attention should be focused on the symptoms of nutritional deficiencies. For example, headache, nausea and diplopia may indicate an intoxication with vitamin A.

Objective examination. An objective examination should include measurement of height and weight, fat distribution and anthropometric determination of muscle mass. The body mass index [BMI = weight (kg) / height (m)] will regulate weight with growth. If the weight of the patient is <80% due, appropriate growth, or if BMI <18, then malnutrition must be suspected. Although these data are useful in diagnosing malnutrition, they are not very specific.

The area of the muscular area of the middle of the upper part of the forearm is the muscle mass of the body. This area is calculated based on the thickness of the skin fold of the triceps (TCST) and the circumference of the middle of the forearm. Both measurements are carried out on the same site, the patient's right arm is in a relaxed position. The average circumference of the middle of the upper part of the forearm is approximately 32 + 5 cm for men and 28 ± 6 cm for women. The formula for calculating the area of the muscular area of the middle of the upper part of the forearm in centimeters in a square is presented above.

This formula corrects the area of the muscular area of the upper part of the forearm, taking into account fat and bone. The average area of the muscular area of the middle of the upper part of the forearm is 54 ± 11 cm for men and 30 ± 7 cm for women. A value of less than 75% of this standard (depending on age) indicates depletion of muscle mass. This measure is influenced by physical activity, genetic factors and age-related loss of muscle mass.

Objective examination should be focused on specific symptoms of nutritional deficiencies. It is necessary to identify symptoms of PEN (eg, swelling, cachexia, rash). The examination should also focus on the signs of conditions that could predispose to a lack of nutrients, such as dental problems. Mental status should be evaluated because depression and deterioration of cognitive abilities can lead to weight loss.

A widespread, complete nutritional assessment (PSP) uses information from a patient's history (for example, weight loss, changes in eating habits, gastrointestinal symptoms), objective examination data (eg loss of muscle mass and subcutaneous fat, edema, ascites) and medical condition assessment nutrition of the patient. The approved Mini-Rating of the Nutritional Status of the patient is used, which is also widely used in assessing the nutritional status of elderly patients.

Diagnosis of malnutrition

The volume of necessary laboratory research is unclear and may depend on the material situation of the patient. If the cause is obvious and can be corrected (for example, the situation is on the brink of survival), research is of little use. Other patients need more detailed evaluation.

Signs and symptoms of malnutrition

Scope / System	Symptom or symptom	Deficiency
General Appearance	Cachexia	Energy
Skin covers	Rash	Many vitamins, zinc, essential fatty acids
	Rash on areas exposed to the sun	Niacin (Pellagra)
	Easiness of appearance of "bruises"	Vitamins C or K
Hair and nails	Thinning or loss of hair	Protein
	Premature graying of hair	Selenium
	Spoon-shaped nails	Iron
Eyes	"Chicken blindness"	Vitamin A
	Keratomalacia	Vitamin A
Mouth	Halit and glossitis	Riboflavin, niacin, pyridoxine, iron
	Bleeding gums	Vitamin C, riboflavin
Limbs	Edema	Protein
Nervous system	Paresthesias and numbness of feet and hands	Thiamine
	Convulsions	Ca, Mg
	Cognitive and sensory disorders	Thiamine (beriberi), niacin (pellagra), pyridoxine, vitamin B
	Dementia	Thiamine, niacin, vitamin B
Musculoskeletal System	Loss of muscle mass	Protein
	Bone deformities ("O-shaped" legs, deformed knee joints, curvature of the spine)	Vitamin D, Ca
	Fragility of bones	Vitamin D
	Soreness and swelling of the joints	Vitamin C
GIT	Diarrhea	Protein, niacin, folic acid, vitamin B
	Diarrhea and perversion of taste	Zinc
	Dysphagia and pain when swallowing (Plummer-Vinson syndrome)	Iron
Endocrine	Thyroid enlargement	Iodine

The area of the muscular area of the middle of the upper part of the forearm in adults

Standard (%)	Men (%)	Women (%)	Muscle mass
100 ± 20	54 ± 11	30 ± 7	Adequate
75	40	22	Allowable
60	32	18	Exhaustion
50	27th	15	Cachexia

The average muscular mass of the middle of the upper part of the forearm is ± 1 standard deviation. According to the I and II National Health and Nutrition Research Programs.

The most commonly used laboratory test is the measurement of the whey protein. Reducing the amount of albumins and other proteins [eg, prealbumin (transthyretin), transferrin, retinol-binding protein] may indicate a deficiency of protein or PEN. With the progression of malnutrition, albumin levels decrease slowly; the levels of prealbumin, transferrin, retinol-binding protein decrease rapidly. The determination of albumin level is quite cheap and allows predicting the risk of complications, mortality and mortality are better than measuring other proteins. However, the correlation of the albumin level with the risk of complications and mortality can be associated with both non-food and food factors. In inflammation, cytokines are formed that cause albumin and other food protein markers to leave the bloodstream into the tissues, reducing their levels in the serum. Since prealbumin, transferrin and retinol-binding protein decrease faster in the fasting process than albumin, their measurement is sometimes used to diagnose or assess the severity of acute starvation. However, it is not completely clear whether they are more sensitive or specific than albumin.

The total number of lymphocytes can be counted, which often decreases with the progression of malnutrition. Insufficient nutrition leads to a significant decrease in CD4 ⁺ T-lymphocytes, so the definition of this indicator is useful in patients who are not sick with AIDS.

Skin tests using antigens help to identify the weakening of cellular immunity in PEN and some other disorders associated with malnutrition.

Other laboratory tests (measuring levels of vitamins and minerals) are used selectively to diagnose their specific types of conditions associated with deficiency of a component.

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