Introduction

Decreases in red blood cell (RBC) or hemoglobin resulting from blood loss, impaired production of RBCs, or RBC destruction.

The prevalence of anemia varies greatly in outpatients, depending on the population examined. Although anemia is common in the elderly, it is never normal. Normal values for Hct and RBC volume are not altered with aging. Because anemia is a sign, not a diagnosis, an evaluation is almost always warranted to identify the underlying cause. At the very least, enough testing should be performed to determine the type of anemia. With that information, the need for further evaluation can better be determined. Often anemia is caused by benign disease and, indeed, may simply be a marker of chronic illness. However, it may be the presenting sign of serious disease, including cancer.

The most diagnostically useful way to classify anemias is by mean corpuscular volume (MCV). This method groups anemias into three categories: microcytic, normocytic, and macrocytic (see Table 69-1). However, some anemias fall into more than one category.

Symptoms and signs generally are similar across age groups, although some may be more common or prominent in the elderly because of underlying, possibly unrelated, diseases. For example, fatigue, shortness of breath, worsening angina, and peripheral edema are more common with anemia when elderly patients also have preexisting atherosclerotic heart disease or heart failure. Mental status changes, including confusion, depression, agitation, and apathy, may occur as presenting symptoms of anemia, even in previously unimpaired elderly persons. Dizziness is also common. Pallor may be less noticeable in the elderly, although it can usually be noticed on the oral mucosa and the conjunctiva.