What hematologic changes occur in older adults that affect blood component assessment?

Older adults experience several hematologic changes that affect blood component assessment, including decreased blood volume, lower plasma protein levels, and reduced production of blood cells by aging bone marrow. Total red and white blood cell counts decline, while platelet counts remain stable. Additionally, immune function diminishes, leading to slower antibody responses and a less pronounced increase in white blood cell counts during infections.

As individuals age, their hematologic profile changes significantly. There is a notable decrease in blood volume and plasma proteins, which may stem from lower dietary protein intake and diminished liver function. Aging bone marrow produces fewer blood cells, resulting in lower total counts of red and white blood cells, although platelet counts do not change. Furthermore, lymphocyte reactivity decreases, leading to a decline in immune responses, including slower antibody production and a reduced ability to mount a strong response to infections.