Anemia Facts and Statistics: What You Need to Know

Anemia is a condition in which red blood cell (RBC) number or function is diminished. There are many types and causes of anemia, with similar symptoms that include fatigue, low energy, pale skin, and a rapid heart rate.

Severe anemia can cause significant health problems, such as heart failure. In rare cases, anemia can be a cause of death. Anemia is common during medical illnesses, and most of the time it’s treatable.

This article will discuss facts and statistics about anemia, including how common it is, risk factors, causes, mortality, and early detection.

How Common Is Anemia? 

Anemia is fairly common. According to one study, 5.6% of the U.S. population meets the criteria for anemia. The condition is more common among older adults, pregnant people, and people of any age who are undernourished.

Often, anemia resolves with treatment, but it can be a chronic condition that requires ongoing management, especially if you have a hereditary cause of anemia. Also, prevention is necessary if you have a health problem, like cancer or malabsorption, that can make you prone to anemia.

According to the Centers for Disease Control and Prevention (CDC), anemia affects 7.4% of men and 7.6% of women between 65 and 74 years, and 39.5% of men and 21.9% of women who are 85 and older in the United States.

The World Health Organization (WHO) estimates that anemia affects 42% of children under age 5 and 40% of pregnant people worldwide.

Anemia by Ethnicity 

Some types of hereditary anemia are especially prevalent among certain populations. Nutritional causes of anemia may be more common in specific geographic regions due to dietary habits or access to nutrition. Additionally, certain groups of people (for example, people who are vegetarians) may be at risk of anemia due to dietary factors. 

Examples of hereditary types of anemia include:

• Thalassemia: This inherited blood disorder can range from mild to severe. It’s more common among people of Middle Eastern, Mediterranean, African, or Asian descent. 
• Sickle cell anemia (sickle cell disease): According to the CDC, sickle cell disease affects 100,000 Americans and is more common among Black or African Americans and Hispanic Americans. The CDC says sickle cell disease affects 1 out of every 365 Black or African American births and 1 out of every 16,300 Hispanic American births.
• Hereditary spherocytosis: This rare type of inherited anemia is more prevalent among people of Northern European descent.
• Fanconi anemia: This hereditary type of anemia is more common among people of Ashkenazi Jewish ancestry (a group who migrated to northern France and Germany before settling in Eastern Europe), the Roma population of Spain, and Black South Africans.

Anemia by Age and Gender 

Anemia is more common among females than males. Females are twice as likely as males to have anemia. Adults have a higher rate of anemia than children. The risk of anemia increases with age. Adults aged 80 to 85 have the highest rates of anemia.

Females have the highest risk of anemia during pregnancy, between ages 40 to 49, and between ages 80 to 85. For males, the rates of anemia increase throughout adulthood.

Causes of Anemia and Risk Factors

There is a wide variety of causes and risk factors for anemia. These include medical illnesses, hereditary conditions, nutritional deficiencies, and medications. 

All blood cells, including RBCs, are produced in the bone marrow. Proper RBC formation requires several nutrients, most notably iron and vitamin B12. Some illnesses prevent the body from making enough RBCs, and some medical conditions cause the RBCs to be malformed. 

Some common causes of anemia are:

• Iron deficiency: Microcytic anemia (small RBCs)
• Vitamin B12 deficiency: Macrocytosis (large RBCs)
• Blood loss: Often causes a low number of RBCs, and sometimes iron deficiency also
• Chemotherapy: Aplastic anemia (inhibits RBC production in the bone marrow)
• Pregnancy: A risk factor for a low concentration of RBCs and iron deficiency
• Malabsorption or malnutrition: Causes nutritional deficiency, with a low number of RBCs, and possibly iron or vitamin B12 deficiency
• Malaria: Causes hemolytic anemia (the RBCs rupture)
• Chronic illness: Consumes nutrients, causes malnutrition, affects the body's ability to use iron to produce RBCs

What Are the Mortality Rates for Anemia? 

Anemia can lead to serious health effects, including loss of consciousness and organ failure. Severe anemia, rapidly worsening anemia, and anemia that occurs with other major illnesses can be fatal.

According to the CDC, anemia accounts for approximately 890,000 hospital emergency department visits per year in the United States and 5,633 deaths per year, which is 1.7 deaths per 100,000 population.

Screening and Early Detection 

In general, a routine yearly physical includes a complete blood count (CBC), which is a standard screening for anemia. Additionally, routine screening for anemia is done during prenatal visits. 

A CBC includes:

• RBC count: Number of RBCs
• White blood cell (WBC) count: Number of WBCs
• Platelet count: Number of platelets (cells that are active in clotting)
• Hemoglobin: The amount of oxygen-carrying protein in the blood
• Hematocrit: The proportion of RBCs relative to blood volume
• Mean corpuscular hemoglobin concentration (MCHC): The average concentration of hemoglobin in RBCs
• MCH (mean corpuscular hemoglobin): The amount of hemoglobin in an RBC
• Mean corpuscular volume (MCV): Average RBC size
• Red cell distribution width (RDW): The range of size of RBCs

If you have anemia, you might also have other tests, such as a microscopic examination of your RBCs, iron levels, a bone marrow biopsy (a sample is drawn from a bone and analyzed in the lab), or a fecal occult blood test (stool is tested for blood).

Along with your symptoms and CBC results, these tests can help determine the cause of your anemia and guide treatment.

If you have a history of anemia or risk factors, such as chemotherapy or chronic illness, you might have regularly scheduled blood tests to follow your red blood cell parameters. 

Summary

Anemia is an inadequate function of or number of red blood cells. It is a fairly common condition, but it's usually mild and temporary. When it's mild, it can cause nonspecific symptoms (those that can be caused by other conditions as well), like fatigue. There are many causes of anemia.

Anemia can occur at any age, but in general, the risk of anemia increases with age. Severe anemia, with a very low RBC count, low hemoglobin, or low hematocrit, can cause serious adverse health effects, or even death. Anemia is usually corrected with the treatment of the underlying cause.