OVERVIEW
Anemia is a condition in which the body does not have enough healthy red blood cells, which normally carry oxygen to body tissues. It is the most common blood condition in the U.S., affecting about 3.5 million Americans. There are many different causes anemia, but the end result is the same: your body does not get enough oxygen because it does not have enough healthy red blood cells to transport the oxygen through your blood. Anemia can be mild or severe. Mild anemia can be virtually asymptomatic while severe anemia can cause low oxygen levels in vital organs such as the heart, which can lead to a heart attack.

RISK FACTORS AND CAUSES
There are over 400 different types of anemia, but they can be divided into three groups: anemia caused by blood loss, anemia caused by decreased or faulty red blood cells production, and anemia caused by destruction of red blood cells. Some examples include the following:

• Anemia caused by blood loss: GI conditions like ulcers, hemorrhoids, gastritis and cancer, chronic use of NSAIDs like aspirin and ibuprofen, menstruation and childbirth in women.
• Anemia caused by decreased or faulty red blood cell production: Sickle cell anemia, iron - deficiency anemia, vitamin deficiency anemia, bone marrow or stem cell problems.
• Anemia caused by destruction of red blood cells: Hemolytic anemia caused by sickle cell anemia, thalassemia, infections, drugs, toxins from advanced liver or kidney disease, autoimmune causes, vascular grafts, prosthetic heart valves, tumors, clotting disorders.

SYMPTOMS
Symptoms of anemia may vary depending on the cause but generally include:

• Fatigue
• Pale skin
• Fast or irregular heartbeat
• Shortness of breath
• Chest pain
• Dizziness
• Cognitive problems
• Cold hands and feet
• Headache

Symptoms may be very mild initially but worsen as the disease progresses.

DIAGNOSIS
In addition to a history and physical exam, your doctor may order blood tests for iron, vitamin B12, folic acid, red blood count, hemoglobin level, reticulocyte (young red blood cell) count, and a variety of other measures.

TREATMENT
Because there are many different types of anemia, there are also many different types of treatment, which are directed at the cause of the anemia. Examples of treatments include blood transfusions, corticosteroids or other medications directed at the immune system, erythropoietin (a hormone that helps your bone marrow make more red blood cells), supplements of iron, vitamin B12, folic acid, or other vitamins and minerals.

PREVENTION
Many causes of anemia are not preventable, but eating a diet rich in vitamins like iron, folate, vitamin B12, and vitamin C can help prevent iron deficiency and vitamin deficiency anemia.

ADDITIONAL INFORMATION
To read more about anemia, please visit:

• PubMed Health
  Anemia
• Mayo Clinic
  Anemia
• WebMD
  Anemia

REFERENCES

• Recommendations to prevent and control iron deficiency in the United States. Centers for Disease Control and Prevention. MMWR Morb Mortal Wkly Rep 1998; 47(RR-3):1.
• Auerbach M, Goodnough LT, Picard D, Maniatis A. The role of intravenous iron in anemia management and transfusion avoidance. Transfusion 2008; 48:988.
• Baker WF Jr. Iron deficiency in pregnancy, obstetrics, and gynecology. Hematol Oncol Clin North Am 2000; 14:1061.