Hemopoiesis

The number of cells in the red bone marrow during the first 30 years of life is reduced by 50%, then stabilizes and remains at this level to 70 years, and in the next 10 years is reduced by another 40%.It is assumed that these changes do not reflect an absolute decrease in the number of hematopoietic cells and the true rate of production of erythrocytes, but characterize the increase in the proportion of adipose tissue in the bone marrow. Nevertheless, the concentration of Hb and the number of erythrocytes in the blood, constant up to the age of 40, gradually decrease to 70 years, in the future, a marked decrease in these indicators occurs in parallel with the change in the cellularity of the red bone marrow.

Changes from erythrocytes include increasing their osmotic resistance, which is considered one of the indicators of adaptation and the general state of the body. Increased osmotic resistance of red blood cells indicates the presence of spherocytes in the blood of older people. There is a tendency to an increase in MCV and variability in the size of circulating erythrocytes. Typical age changes in the main blood hematologic parameters are shown in Fig.12-5 [Lapin A., 2003].

Anemia is one of the most common hematologic syndromes in elderly patients. The incidence of anemia increases with age: in the 7th decade of life it is 90.3 per 1000 in men and 69.1 in women over the age of 85, anemia is already detected in 27-40% of men and 16-21% of women.

The following variants of anemia are pathogenetically distinguished: iron-deficient;associated with a violation of heme synthesis( sidero-achestic anemia, heme synthase deficiency);associated with a violation of DNA synthesis - megaloblastic( vitamin B12-deficient and folio-deficient);caused by violation of iron transport( atransferrinemia);hemolytic;associated with a violation of the regulation of erythropoiesis( increased content of erythropoiesis inhibitors).

In elderly people, there are changes in laboratory indicators characterizing the status of iron in the body. The concentration of iron in the blood serum decreases with age, and the serum ferritin content, as well as the iron depot in the red bone marrow, increases, which indicates a violation of iron consumption by the precursors of erythrocytes [Lapin A., 2003].Reduction of serum iron concentration in the elderly is due to achlorhydria or insufficient intake of vitamin C with food, which reduces the absorption of iron in the small intestine.

In patients with iron deficiency anemia, reduced iron content in serum generally stimulates an increase in the concentration of

. Fig. Change in the number of erythrocytes in the blood, depending on the age of the

Fig. Change in the number of erythrocytes in the blood, depending on the age of the

Fig. Change in the concentration of Hb in the blood, depending on the age of the

Fig. The change in the concentration of Hb in the blood as a function of age

Fig. Change in Ht as a function of age

Fig. Change in Ht as a function of age

Fig. Change in MCV as a function of age

Fig. Change in MCV as a function of age

Fig. Change in serum iron concentration depending on

age

Fig. The change in serum iron concentration, depending on

transferrin, does not occur in the elderly, which is due to a decrease in the synthesis of transferrin in the liver.

The most common cause of iron deficiency anemia in the elderly - loss of iron due to microcirculation of the gastrointestinal tract, additional iron deficiency, impaired absorption( eg, with functional pancreatic insufficiency), persistent small bleeding from the oral cavity due to problems with dentures, nephrogenic hematuria.

The blood loss resulting in iron deficiency is characterized by a small amount of lost blood, duration and often leak unnoticed.

The average concentration of vitamin B12 in the serum in the elderly is clearly reduced. The concentration of folic acid decreases between 60 and 90 years, but after 90 years it increases and approaches the indicators of young people. A significant decrease in the concentration of vitamin B12 or folic acid often leads to the development of macrocytic anemia in the elderly.

The frequency of vitamin B12-deficiency anemia increases with age and is about 0.1% in young people, up to 1% in the elderly, and after about 75 years it is found in about 4%.In Russia, the frequency of vitamin B12-deficiency anemia is 100 times lower than in other countries of the world [Vorobiev P., 2001], which may be due to the widespread use of vitamin B12 in the treatment of a variety of diseases, and primarily - in the pathology of the nervous system.

Deficiency of vitamin B12 in the elderly is most often due to a violation of its absorption due to atrophy of the

mucosa of the

age, either because of a competitive intake of the intestinal microflora or helminths.

A large group of anemia in the elderly is composed of anemia of mixed origin, that is, due to a combination of two factors and more. In most cases, in older people, such anemia is caused by chronic diseases and has the following characteristics.

■ Normochromic erythrocytes are of conventional size and shape.

■ As a rule, there is no leukopenia and thrombocytopenia or there are multidirectional changes in the content of leukocytes and platelets.

■ The reticulocyte content is normal or slightly elevated.

■ The cytological picture of the red marrow is not changed.

■ The rate of ripening of erythrocytes is slowed down.

■ The average life span of erythrocytes is moderately reduced.

■ The concentration of erythropoietin in the blood is normal or slightly elevated.

■ The concentrations of vitamin B12 and folic acid in the blood are normal.

The total number of leukocytes1o2b, the content of monocytes and eosinophils

remain constant at the age of 30-80 years. The number of neutrophils slightly increases in men and slightly decreases in women at the same age interval. In elderly and elderly people, the decrease in the lifespan of leukocytes is noted. After 55 years and especially after 70 years, the granulocyte reserve of red bone marrow decreases. This circumstance is associated with a less pronounced output of neutrophils from the red bone marrow to the blood in elderly people in response to bacterial infections compared to young people.

As the patient ages, the concentration of cholesterol increases in the blood, the albumin / globulin ratio decreases, MCV increases, which increases the ESR.As a result, in the aging process, ESR increases significantly in men and women. So, if in young adult men it does not exceed 10 mm / h( according to Westergren), and in young women - 20 mm / h, then in men after 50 years the ESR often exceeds 15 mm / h, in 50-85-year-olds -20 mm / h, and after 85 years - 30 mm / h. Women of the same age group have ESR values ​​of 20, 30 and 42 mm / h, respectively. The change in ESR as a function of age is shown in Fig.[NCCLS, 2000].

As the aging progresses, the hemostasis changes. After 40 years, there is an increase in procoagulant activity of blood and intravascular thrombogenesis. This manifests itself as an increase in the concentration of PDP, the activity of factor XIII, increasing plasma tolerance to heparin. In parallel with an increase in procoagulant activity of the blood, activation of fibrinolysis is noted, but it lags behind the growth of pro-coagulant blood properties. The age-related decrease in fibrinolytic activity is mainly due to an increase in the concentration of inhibitors of plasminogen activation and stimulation of antiplasms, a decrease in ATP activity, and an increase in anti-heparin activity.