This release reports on two separate studies, one combing the medical histories and records of more than 6,000 women, and another where 96 patients were surveyed. In the first study, researchers found that a significant number of young women had iron deficiency that wasn’t quite as severe as anemia. In the second study, they tried to find a way to predict who might have iron deficiency by asking about fatigue and other factors, but were unable to find a predictive question. The release declares that doctors should screen all teens for “iron deficiency” but this conclusion seems beyond the scope of the two studies. Finding teens who may suffer health issues from iron deficiency is a great goal. However, whether universal screening is the best way requires further research.
For more context about the potential harms of over-screening, see this blog post from our archives.
Screening every 16-year-old girl in the US for “iron deficiency” may not be the best idea. This news release goes too far in reporting on two studies about iron deficiency, which is a health issue for some teens. Readers are not given any balancing context on whether the screening could cause anxiety or lead to false-positive diagnoses that could lead to unnecessary treatment.
These studies were exploratory and attempt to identify factors that medical staff could use to more selectively screen teens (or screen earlier) for iron deficiency. The American Academy of Pediatrics does not recommend routine screening for anemia. The release stated that several adverse associations exist with anemia (lower math scores, poor attention) but those are likely associated with more severe anemia and it is not clear that the relationship is causal. In fact, screening more aggressively for iron deficiency could result in over-treatment.
The release mentions that existing hemoglobin tests are affordable, but that screening for iron-deficiency below the level of anemia can be costly. This squeaks by as discussing “costs” but we wish figures had been offered. Is affordable $2 or $20? Is costly $100 or $500? Numbers would help readers better understand the cost implications of screening.
Both studies summarized in the release relate to measuring iron deficiency in adolescents, but the release doesn’t provide any numerical context to show specifically how teens would benefit from more aggressive screening. Will identifying these teens prevent specific health problems?
The release relies on associations but not proven relationships between deficiency and poor health.
Here is an excerpt: “Women are typically tested some time in their teens for anemia — the severe form of iron deficiency — using a quick and affordable hemoglobin test. However, iron deficiency can develop years before anemia and can be missed by hemoglobin testing alone.”
The release is suggesting that before the “severe form” of iron deficiency is measured, there may be a less severe form. But this is not defined or quantified. Readers cannot judge how important the potential new screening would be without knowing how and when it would have a benefit and the definition of that benefit.
Here is where the release addresses some potential benefit:
“Iron deficiency without anemia has been associated with lower standardized math scores, attention deficit disorder and restless leg syndrome in children and adolescents. Among iron-deficient adolescent women there is a future risk of maternal iron deficiency and negative effects on infant health.”
But the association is not the same as proof that the less severe form of iron deficiency is the cause of lower math scores, or other conditions listed.
Screening is not without harms. The release does not mention any potential harms or downsides from identifying more teens with iron deficiency, or pre-anemia. Would a positive screen result in iron supplementation or a change in eating habits? Some research has suggested that mild iron deficiency is protective.
Iron supplementation is associated with constipation and too much iron is harmful to the liver, heart and other organs. A harm to society might be more financial drain on an already strained health care system if widespread screening were adopted.
The release describes the two studies and gives enough details about their methods and the questions they were trying to answer for readers to judge the quality of the evidence. However, contrary to the release headline, the two studies that were published do not contain specific recommendations for expanded or universal screening for iron deficiency. In the release itself, the study’s main author is quoted saying:
“I think we need to establish the optimal timing for an objective assessment of adolescent iron deficiency and anemia.” She does not say that she knows the optimal timing.
She further states that more research is needed.
“In addition to timing, further research will be needed to determine which blood test for iron deficiency without anemia is accurate, cost-efficient and practical for routine doctor’s office use.”
The release would have been stronger if it had included a sentence reminding readers that association is not causation. We don’t know that changing the iron levels in teens prevents any of the problems listed.
There is probably very little harm and possibly some benefit to having lower iron stores, but the headline makes it seem like a disease.
The release identifies the source of grant funding for both journal articles referenced. We wish it had also said “there are no conflicts of interest.”
The alternative to expanded screening is the status quo so this category is not applicable. However, the release does note that once identified through additional screening, “Iron deficiency can be corrected with dietary changes and supplementation.”
The release states that low-cost hemoglobin tests are affordable and given to most young women, but that more sensitive tests that screen for iron deficiency are more costly and thus “difficult to obtain in the doctor’s office.”
The release does not make a claim of novelty.
The headline, “Earlier blood testing for iron deficiency, anemia recommended for young women” is unjustified and is not supported by the study findings.