The importance of Blood in aging
Defining and detecting anemia
Anemia means having a lower-than-normal count of red blood cells circulating in the blood.
Red blood cells are always counted as part of a “Complete Blood Count” (CBC) test, which is a very commonly ordered blood test.
A CBC test usually includes the following results:
A “normal” level of hemoglobin is usually in the range of 14-17gm/dL for men, and 12-15gm/dL for women. However, different laboratories may define the normal range slightly differently.
Anemia is often described as:
Symptoms of anemia
The red blood cells in the blood use hemoglobin to carry oxygen from the lungs to every cell in the body. When a person doesn’t have enough functioning red blood cells, the body begins to experience symptoms related to not having enough oxygen.
Common symptoms of anemia are:
The most common causes of anemia
Compared to most cells in the body, normal red blood cells have a short lifespan: about 100-120 days. A healthy body must produce red blood cells. This is done in the bone marrow and takes about seven days, then the new red blood cells work in the blood for 3-4 months. Once the red blood cell dies, the body recovers the iron and reuses it to create new red blood cells.
Anemia happens when something goes wrong with these normal processes. In kids and younger adults, there is usually one cause for anemia. But in older adults, it’s quite common for there to be several co-existing causes of anemia.
The decrease in immune function mediated by lymphocytes is the most significant change with aging. Thymus involution occurs after puberty and total thymic atrophy occurs by late middle age. With these changes, thymic-mediated T lymphocyte development disappears and older individuals are dependent on their existing T lymphocyte pool to mediate T cell-dependent immune responses. In the absence of thymic function, the number of naive T cells decreases in older individuals and memory T cells are the predominant type. B lymphocyte function is dependent on T cell accessory roles and the decreased ability to generate antibody responses, especially to primary antigens, may be the result of T cell inadequacies rather than an intrinsic fault of B lymphocytes.
Natural killer cells are increased in number, but their function is disturbed. Delayed hypersensitivity reactions are reduced in the elderly. These immunologic deficits are correlated with overall mortality in individuals over age 60. Serum immunoglobulin M and G concentrations do not change significantly in older people. Serum IgA levels increase with age. An increased prevalence of autoantibodies (e.g., anti-IgG rheumatoid factor) occurs in older people. Monoclonal plasma immunoglobulins (essential monoclonal gammopathy) are found with increasing frequency with age, reaching three percent in people over age 70 and nearly six percent in those from 80 to 89.
Few pieces of advice on the treatment of anemia:
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