The retrospective study, which was published online in JAMA Paediatrics, found that prescribing iron led to a significant reduction in ZPP levels over an average of 10 months, particularly among anaemic children. The researchers, led by Hema Magge, MD, reported that if children of a lower socioeconomic status were ZPP screened, not only would their wellbeing be more secure against iron deficiency, but they could ultimately be less at risk of neurodevelopmental defects.
ZPP forms when iron is in short supply in your blood, meaning that zinc combines with protoporphyrin in place of iron during the final stages of haemoglobin synthesis. Though other factors, such as lead poisoning, can affect your ZPP levels, the researchers say that, in the absence of lead toxicity, ZPP is a sensitive, inexpensive and specific measure of iron deficiency.
For the study, the team examined Boston Medical Centre’s primary care clinic’s medical records from the beginning of 2002 to the end of 2010. They found that 2,612 children had routine screening for blood cell count, lead, and zinc between ages 8 months and 18 months, most of whom (65%) were African American. 48% of the sample had elevated ZPP, but 84% of these were not anaemic. Iron was prescribed to just 18% of the children with abnormal ZPP, but the researchers noted that, during a 10-month follow-up, markers of iron status, including ZPP, improved for all children during that time, albeit with the strongest improvement occurring in those who had taken the supplement.
Robert Baker, MD, PhD, of Children’s Hospital of Buffalo, wrote in an accompanying editorial, it’s ‘no consolation that ZPP levels tended to normalize with age and without treatment,’ when you think that other studies have shown ‘measurable neurodevelopmental deficits years after correction of iron deficits.’ Also, by using haemoglobin as the primary screening test, Baker warned that the AAP recommendation ‘misses the large group of infants and toddlers that has iron deficiency but not iron deficiency anaemia.’