Anemia Screening

Excerpt

Anemia is a common sign in both inpatient and outpatient settings and is defined as a decrease in the number of circulating red blood cells or hemoglobin. Oftentimes anemia is not evaluated or managed adequately. It is routinely listed as a freestanding diagnosis, however, it is in fact a clinical sign indicating the presence of an underlying etiology and additional workup is required to elucidate its cause. Anemia leads to diminished tissue oxygenation and can worsen the progression of many coexisting diseases. Despite this, there remains clinical discordance in both the formal definition of anemia and in protocols to screen for it .

Symptoms of anemia are diverse and can include fatigue, weakness, lightheadedness, headache, pallor or jaundice, tachycardia, palpitations, chest pain, dyspnea, cold distal extremities, and claudication. These signs and symptoms vary in prevalence and magnitude.

Anemia causes a decrease in the relative number of circulating red blood cells or hemoglobin, which leads to a consequent decrease in the amount of oxygen delivered to tissues. However, the hemoglobin concentration constituting anemia varies based on factors such as gender, ethnicity, and age. In addition, opinions differ as to which patient populations should undergo routine screening for anemia. Finally, the threshold for initiating treatment and the goals of treatment are subject to variation according to discipline and medical condition .

In 2010, the World Health Organization (WHO) criteria for diagnosing anemia required hemoglobin levels less than 12 grams per deciliter (g/dl) in premenopausal females and 13 g/dl in postmenopausal females and males of all ages. The journal Blood disagreed with these standards, citing the paucity of WHO data and proposed new thresholds for anemia based on race, gender and age. These proposed standards defined anemia as hemoglobin levels of less than 13.7 g/dl for white men between 20 and 60 years of age, less than 13.2 g/dl for white men older than 60, and white women of all ages were considered anemic at 12.2 g/dl. Although this journal did reference a significant difference in hemoglobin levels in black men and women, no standard levels for the diagnosis of anemia in these populations were proposed. Currently, the majority of the literature utilizes the WHO standards for consistency.

There is a similar discordance concerning screening for anemia between the US Preventative Services Task Force (USPTF), various individual medical academic institutions, and what is done in the day-to-day practice of medicine. For example, the USPTF issued a statement on screening for iron deficiency anemia in asymptomatic children between 6 and 24 months of age, stating that there was insufficient evidence on the benefits versus harms of screening for anemia in children in this age group. At the same time, the American Academy of Family Practice released its position statement: "Universal screening for anemia should be performed at 12 months of age, with measurement of hemoglobin levels and an assessment of risk factors associated with iron deficiency and iron-deficiency anemia." The issue of screening in pregnant women presented a similar discordance. "The USPTF concludes that the evidence of the effect of routine screening for iron deficiency anemia in asymptomatic pregnant women on maternal health and birth outcomes is insufficient...and the balance of benefits and harms cannot be determined." The American Academy of Family Practice voiced agreement with the USPSTF. The American College of Obstetrics and Gynecology in Practice Bulletin No. 95 issued the position statement, "All pregnant women should be screened for anemia and treated if necessary." At present, there are no recommendations for routine anemia screening of non-gravid, well adults.