Iron Deficiency Anemia and Early Childhood Caries

Association between iron deficiency anemia and early childhood caries

• Tommy Ye

Background:

Early childhood caries (ECC) and iron deficiency anemia (IDA) are a global health problem in both the developing and developed countries such as China, India, United States (US) and the United Kingdom. ECC is a term coined by the Centers of Diseases and Control (CDC) at a 1994 workshop “in an attempt to focus attention on the multiple factors (i.e. socioeconomic, behavioral, and psycho-social) that contribute to caries at such early ages, rather than ascribing sole causation to inappropriate feeding methods (Colak, 2013).” As the American Academy of Pediatric Dentistry states, ECC can be only be defined as “the presence of any smooth surface caries for children under the age of 3 and the presence of one or more smooth surface lesions in any primary maxillary anterior teeth for those 3 to 5 years of age (or a dmft [decay, missing, filled, teeth] score of ≥ 4 (age 3), ≥ 5 (age 4), or ≥ 6 (age 5))” (Schroth, 2013). These are the same definitions and criteria that most dental practitioner used to assess children of early childhood caries. ECC commonly starts off as a demineralization of the enamel, which leads to severe decay in mostly the cervical regions of primary maxillary incisors and then later into the other anterior teeth. The decay, in some cases, can also affect the labial and/or lingual surfaces of the maxillary anterior teeth. The etiology of ECC is very complex and is considered multifactorial, but one commonly accepted etiology is the “associat[ion] with frequent consumption of fermentable carbohydrates and improper bottle- or breast-feeding practices (Tang, 2012).”

Anemia is the reduction of the total circulating red cell mass below the normal limits, which in return reduces the oxygen-carrying capacity of the blood and ultimately tissue hypoxia and ischemia. Anemia is classified by either its cause (hemolytic anemia, thrombocytopenic anemia, etc.) or its RBC size (macrocytic, microcytic anemia). Nearly half of anemia cases are caused by iron deficiency anemia (IDA), where IDA is “the consequences of the lack of iron for hemoglobin synthesis (Shaoul, 2011).” IDA is prevalent among young children and pregnant women. If left untreated, IDA can lead to the mental and physical development of children and increased death and morbidity of the other anemic patients. Diagnostic exam used to establish the diagnosis of IDA is the peripheral blood smear. With the blood smear, we want to analyze “ferritin, hemoglobin, and Mean Corpuscular Volume (MCV), as they are key biochemical indicators of iron status (Schroth, 2013).”

As you can see above, both ECC and IDA are very similar health problems that can both affect children and the patients’ quality of living tremendously. Some studies have shown that “dental caries and its resulting discomfort and pain can interfere with proper nutrition including iron intake, causing IDA (Shaoul, 2011).” This research has shown that there is some connection between ECC and IDA. Despite the fact that ECC and IDA are global health problems declared by the World Health Organization (WHO), there is not enough strong evidence to highlight the close relationship between the two conditions and the mechanism used to explain this deadly relationship. In this report, I aimed to use my clinical case and analysis of multiple studies to prove my point that there is a strong association between iron deficiency anemia and early childhood caries and that more needs to be done to address this concern in terms of dental management and treatment.

Introduction of F.B. and her presentation of condition or risk:

F.B., a 25-year-old woman with a history of iron deficiency anemia and early childhood caries, presents to New York University College of Dentistry (NYUCD), for a dental check up. She takes no medication for her anemic condition and review of the CBC from her MD were all within the normal limits. On exam, she needs several restorations and multiple fixed prosthodontic works.

Methodology:

Clinical Question: In ECC patient, will patient with iron deficiency anemia increase their chances of having more dental caries and periodontal problems in the future, compared to patient without a significant medical history?

PICO: PECC patient, Ipatient with iron deficiency anemia, Cpatient without a significant medical history, and Oincrease their chances of having more dental caries and periodontal problems

Literature Search: Literature searches were done in PubMed using the keywords “iron deficiency” and “anemia” with the Boolean operator “and.”

Literature Review:

From the literature search, I found three articles that were applicable to the clinical question and the aim of this report. The three articles are listed below:

1. “Association between iron status, iron deficiency anemia, and severe early childhood caries: a case-control study” by Robert J. Schroth et. al
2. “The Association of childhood iron deficiency anemia with severe dental caries” by Ron Shaoul, et. al
3. “Relationship between dental caries status and anemia in children with severe early childhood caries” by Ru Shing Tang, et. al

The goal of Schroth’s study was to investigate the relationship of the different iron and hemoglobin levels btn the ECC and caries-free patients. In order to do such a thing, Schroth and the others decided to perform a case control study. They recruited 266 children, where 144 of them have ECC and the last 122 of them are caries-free. ECC patients were all recruited from Winnipeg, Canada between October 2009 and August 2011. All of these children fulfilled the inclusion criteria where they must have “severe tooth decay involving multiple primary teeth necessitating rehabilitative dental surgery under general anesthetic (GA) (Schroth, 2013).” The caries-free patients were the control group and were recruited from the same area and time period. They all “underwent a dental assessment, without radiographs, by [the researchers] to ensure they were caries-free (dmft = 0) (Schroth, 2013).” Both the ECC and the caries-free patient must be healthy and are less than 72 months of age; the average age of all the participating children were 40.8  14.1 months.

Schroth and the others collected demographic data by making the parents of the children answer an interviewed questionnaire regarding their “child’s nutritional habits, use of supplements, physical and oral health, oral hygiene and dental habits, socioeconomic status (e.g. household income), and family demographics. (Schroth, 2013).” Afterward, they collected serum samples of all but 4 children in the operating room by the attending anesthesiologist. From the laboratory results, Schroth and the others were able to obtain the necessary data to arrive at the following conclusions:

1. Children w/ ECC had significantly lower ferritin status and hemoglobin levels than caries-free children
2. Children w/ ECC had significantly greater odds for iron deficiency and iron deficiency anemia than caries-free children

This conclusion helped to reinforce and help to support the authors’ claim that there is an indeed an association between iron deficiency anemia and early childhood caries. The authors do not understand the reasons why that is the case, but they hypothesized that it might be due to the body’s inflammatory response that accompanies from dental caries. They believed that “inflammation associated with ECC may trigger a series of events which ultimately leads to the production of cytokines, which may, in turn, inhibit erythropoiesis and thus reduce the level of hemoglobin in the blood (Schroth, 2013).” Dental caries may also cause severe pain and discomfort for the ECC patient, which may, in turn, caused the patient to eat less and hence the low iron level. Ultimately, the decrease in hemoglobin and iron are the main contributor to anemia or IDA.

The purpose of Shaoul’s study was to investigate the differences in the levels of hemoglobin (Hb), iron, and other anemic indicators before and 4-6 months after an ECC dental restoration. In order to do such a thing, Shaoul and the others decided to perform a case control study. They recruited 155 children, where 33 of them are the control group, who visited the dental clinic for treatment for ECC at Bnai Zion Medical Center in Haifa, Israel between January 2007 and September 2008. All of these children fulfilled the inclusion criteria where they have to all be healthy with no chronic diseases and all within the age range of 3-18 years old who are presented with ECC and microcytic anemia that are caused by IDA. The exclusion criteria “included chronic or acute illness, known blood dyscrasia, any known form of haemoglobinopathy, children who had undergone abdominal surgery or had been diagnosed with malignancy (Shaoul, 2011).” The 30 children that were selected, as the control group, must meet these additional inclusion criteria where they must be presented for an elective minor surgery such as inguinal or umbilical hernia repair, orchiopexy and circumcision and is also caries-free upon examination. For the other 122 children, the surfaces of all their erupted teeth were assessed with the DMFTS index and they must have “had six or more teeth that required restoration treatment“ to be actually included in this study (Shaoul, 2011).

In order to consider the confounding variables that may skew the results of their study, Shaoul and the others collected the age, sex, height, weight and the number of teeth that needs to be treated from both groups. Afterward, they obtained 5 mL serum samples of two groups before and 4-6 months after an ECC restorative procedure. From the laboratory results, Shaoul and the others were able to obtain the necessary data to arrive at the following conclusions:

1. ECC and caries-free children had significantly low BMI, Hb, iron, ferritin, MCV, and RDW (or red cell distribution width) levels before an ECC restorative procedure
2. There are significant differences between the Hb, iron, ferritin and RDW levels 4-6 months before and after an ECC restorative procedure

This conclusion highlighted that there is an association between iron deficiency anemia and early childhood caries. In addition to that, this study have also demonstrated that a dental treatment of a ECC lesions can effectively restore the anemic indicators to a non-IDA level, without the need of any supplemental iron. The authors are unsure how there is an association between IDA and ECC, but they hypothesize that it might be due to malnutrition (which can explain the low BMI in the results) or due to inflammation from dental caries.

The objective of the last study by Tang et. al was to evaluate the nutritional status of an ECC patient and the relationship with IDA. In order to do such a thing, Tang and the others decided to perform a case control study. They recruited 101 children between 2 and 5 years of age who visited the Department of Pediatric Dentistry of Kaohsiung Medical Center. All of these children fulfilled inclusion criteria where they must be diagnosed with ECC according to criteria established by the American Academy of Pediatric Dentistry. The exclusion criteria included “children with medical problems, mental or physical disabilities, and those who had been born prematurely (Tang, 2012).” Demographic information such as sex, income, body weight and height were obtained from most parents except 50 parents who did not provide their income via a questionnaire. The surfaces of all the children’s erupted teeth were assessed with the DMFT and DEFS indices.

In order to adjust for the confounding variables that can skew the result of the study, Tang and others obtained the age, gender, BMI, and mother’s education. Besides obtaining the demographic information, Tang and the other also collected blood serum from all but two participants. With this sample, Tang and the others were able to arrive at the following conclusion:

1. Children with ECC had significantly greater odds for anemia and IDA and are independently associated with each other.

This conclusion demonstrated that children with ECC are at an even higher risk than caries-free patients for anemia and IDA and that this association between ECC and IDA is a very deadly combination that needs to be addressed as early as possible by pediatric dentists and pediatricians. The authors do not understand the etiology behind this association but they provided their own hypotheses behind it. They argued that children with ECC cannot consume iron-rich and vitamin-C rich food because of the pain and discomfort they felt and as a result, they are forced to rely on softer food that does not impinge on their teeth by drinking lots of cow’s milk. Furthermore, because the children with ECC have lots of dental caries, they are suffering from inflammation from these caries that may “induce the production of cytokines that suppresses the synthesis of Hgb (Tang, 2012).”

In relationship to the Literature analysis form (LAF) adapted from Dr. Ralph V. Katz of NYUCD, (presented below) the above three articles all lack a null hypothesis and can contribute to a moderate statement of causation for being a case control study. All authors have clearly separated the independent variables by using a control group, eligibility criteria, and adjusted statistical analyses such as the Chi-square and T-test in the first and third study and T-test in the second study. Almost all of the findings were of statistical significance (P<0.001) and were stated in the above conclusions for each of the studies. Because this is a case control study, the authors can claim a “cause and effect” relationship. Regardless that authors can claim this relationship, there are some flaws in all of the studies. Almost all of the children in all studies are from the lower socioeconomic status. This is not indicative of the whole population in Canada, Israel, and Taiwan respectively from the first to the last study that the authors can properly labeled their cause and effect relationship.

Description of F.B.:

F.B. emigrated to the U.S. at age 15 from Albania with her parents, in pursuit of the American Dream. She drinks socially and do not smoke. She is a dental student at NYUCD. Upon entering dental school, F.B. had poor oral hygiene where she did not floss regularly but brushes twice a day. She consumed a heavy carb-rich diet. Her iron deficiency anemia has been better controlled through a well-balanced diet that includes iron and folate intake. This had been confirmed via a CBC, where all anemic indicators were within the normal limit. She had no other significant medical history. Her vital signs were within the normal limits as well.

Discussions:

The general consensus of the three articles clearly indicates that there is clearly a relationship between ECC and IDA and that more studies needs to be done to determine the actual etiology behind this association. Despite all the evidence that show that there is an association, the studies including the above three articles that are available are just not substantial to show a strong causation. In addition, the limitations in each of studies that I described above are also making these articles less convincing to incorporate into our dental practices.

Conclusion:

Despite the fact that the studies do not show a strong causation for the association between ECC and IDA, the evidence is convincing enough that warrants further research and questions among the dental and medical communities throughout the world. The evidence also helped to answer my clinical question if ECC patient with IDA (in this case, patient F.B) will increase their chances of having more dental caries and periodontal problems in the future. As you can see from the results provided by the three articles, there might be some connection between ECC and IDA and can cause more dental decay or worsen the patient’s IDA condition if left untreated, which was noted in Shaoul et. al’s studies. These results prompted me to make some modifications of my dental management for patient F.B. I would put patient F.B. on more frequent recall and on an aggressive fluoride therapy due to her past ECC history. I will complete all dental restorations or restore any defective restorations prior to performing any prosthodontic work. To make sure that she understands the association between ECC and IDA, I would also make sure to monitor her blood count frequently and reinforce oral hygiene instructions.

Works Cited

Çolak, H., Dülgergil, Ç. T., Dalli, M., & Hamidi, M. M. (2013). Early childhood caries update: A review of causes, diagnoses, and treatments.Journal of Natural Science, Biology, and Medicine,4(1), 29–38. Doi:10.4103/0976-9668.107257

Tang et al. (2012), Relationship between dental caries status and anemia in children with severe early childhood caries. Kaohsiung Journal of Medical Sciences, 29, 330-336.

Schroth et al. (2013), Association between iron status, iron deficiency anaemia, and severe early childhood caries: a case–control study. BMC Pediatrics 13(22), 1-7.

Shaoul et al (2011), The Association of childhood iron deficiency anemia with severe dental caries. Acta Pediatrica 101, e76-9.

Appendix:

LAF:

Photographs of F.B.