Australian Dental Journal

The official journal of the Australian Dental Association

Australian Dental Journal 2021; 0: 1–10

doi: 10.1111/adj.12842

Iron deficiency anaemia and early childhood caries:

a cross-sectional study
WE Mohamed,* RK Abou El Fadl,†,‡ RA Thabet,* M Helmi,†,§ SH Kamal*,¶
*Faculty of Medicine, Ain Shams University, Cairo, Egypt.
†Department of Pediatric Dentistry and Dental Public Health, Faculty of Dentistry, Ain Shams University, Cairo, Egypt.
‡MPH, Imperial College London, London, UK.
§Institute of Tropical Medicine and International Health, Charit
e Universit€atsmedizin Berlin, Berlin, Germany.
¶Department of Pediatrics and Neonatology, Egyptian Ministry of Health, Cairo, Egypt.

ABSTRACT
Background: This study aimed to assess the association between iron deficiency anaemia (IDA) and dental caries in early
childhood.
Methods: A total of 40 children with proven IDA and another 40 healthy age and sex-matched children were enrolled in
this cross-sectional study. Legal guardians were interviewed to collect data on oral hygiene measures and dietary habits.
Anthropometric measurements were performed for all participants, and blood samples were collected to assess complete
blood count and body iron status. Patients were confirmed to have IDA based on haemoglobin level (Hb), red blood cells
indices and body iron status. Caries experience was determined based on the number of decayed, missing and filled pri-
mary teeth using dmft index.
Results: A statistically significant negative correlation between dmft index scores and haemoglobin level (r = 0.454,
P < 0.001) and mean corpuscular haemoglobin (MCH) level (r = 0.380, P = 0.001) was detected, and in accordance
there was a positive statistically significant correlation between caries experience and the presence of anaemia
(r = 0.60, P < 0.001).
Conclusion: In early childhood, dental caries might coexist with IDA even in its mildest form. All children exhibiting
severe early childhood caries should be investigated for IDA and anaemia should be managed if present.
Keywords: Early childhood caries, iron body status, iron deficiency anaemia, malnutrition.
Abbreviations and acronyms: Dmft = number of decayed, missing and filled primary teeth; ECC = early childhood caries; Hb = hae-
moglobin; IDA = iron deficiency anaemia; MCH = mean corpuscular haemoglobin.
(Received 24 January 2021; Revised 26 March 2021; Accepted for publication 6 April 2021.)

include child’s genetic makeup, teeth morphology and

BACKGROUND
enamel hypoplasia.7,8 Early infant feeding malprac-
Early childhood caries (ECC), one of the most com- tices also play a role in caries development, where
mon diseases in early years of life, is considered a seri- bottle feeding at night appears to adversely affect oral
ous public health problem.1 Though preventable, health.9 Similar to other chronic conditions, it has
globally over 530 million children have decay in their been widely reiterated that dental caries follows a
primary teeth,2 and the condition is highly prevalent social gradient such that, within countries, children
in both developed and developing countries.3,4 In from low-income families or those living in deprived
Egypt, dental caries is considered a serious public and underserved areas are at higher risk to develop
health issue among children and adolescents with ECC than children from affluent households.10
prevalence rates as high as 70%.5,6 Unless addressed, ECC is associated with multiple
ECC is a complex, multifactorial disease, based on adverse effects ranging from local pain, to abscess for-
the interplay of various individual risk factors and mation, which lead to difficulty in mastication, mal-
social determinants to promote its initiation and pro- nutrition and sleep disturbance thus hampering
gression. High-sugar diet and poor oral hygiene are normal growth and development at early life stages.11
both considered behavioural cornerstones in the dis- Moreover, ECC has been related to stunting and
ease development and progression. Other factors underweight especially in low- and middle-income

© 2021 Australian Dental Association 1

WE Mohamed et al.

countries12,13 and conversely to obesity in developed informed consent was obtained from children’s legal
countries.14 guardians. This study is compliant with the ethical
In the same manner, iron deficiency anaemia (IDA) principles of declaration of Helsinki for medical
is a major health issue which according to the 2016 research involving human subjects and follows the
Global Burden of Disease study, affected over 1.24 standards of the STROBE statement for strengthening
billion individuals and was identified as the leading the reporting of observational studies in epidemiol-
cause of years lived with disability (YLDs) among ogy.27
populations with low-middle socio-demographic
index.15 According to Egypt’s Demographic and
Study population
Health Survey (DHS), prevalence rates of anaemia in
children aged 6–59 months ranged from 23% to Based on results from a previous study,28 the sample
45%.16 IDA is a common disorder among infants and size was determined using power and sample size
preschoolers owing to high-iron requirement which is (PASS) software, setting alpha error at 5% and power
usually unmet due to inadequate iron intake17 particu- at 80%; the minimum needed sample was 35 healthy
larly in the context of poverty, chronic food insecu- and 35 anaemic children. A convenient sample of 105
rity, and low access to iron-rich foods such as red children aged 24–71 months was recruited from the
meat.18,19 Despite being asymptomatic in most general paediatric outpatient clinic of ASU where only
cases,20 children with IDA may suffer from easy fati- common childhood conditions and minor illnesses
gue and decreased activity.21 ID even without anae- such as fever or bronchitis are managed. Only chil-
mia was found to impair psychomotor, behavioural, dren with full primary dentition were included; how-
cognitive and mental developmental functions in chil- ever, those who were suffering from any chronic
dren and can adversely affect academic performance diseases such as neoplasia or chronic kidney disease
in the long run.22,23 Furthermore, the immune system or were receiving medications or supplements affect-
is affected by IDA thus increasing susceptibility to ing serum haemoglobin levels or increasing liability to
infection due to defective functions of leukocytes and caries experience such as anti-asthmatic inhalers were
lymphocytes and defective production of interleukins excluded (Fig. 1).
including IL-2 and IL-6.23,24
Some commonalities exist between IDA and ECC,
Data collection
where both conditions occur more frequently in low
socio-economic classes. Moreover, among children,
History taking
both iron levels and oral health status are immensely
affected by early feeding practices and quality of The legal guardians of the study participants were
diet.25,26 Despite the high global burden of both den- interviewed to collect data on the child’s age (in
tal caries and IDA in early childhood, there is paucity months), order of birth, frequency of sugar intake and
in evidence on the association between the two health oral hygiene practices. Socio-economic status (SES)
issues. Thus, the current study aimed to investigate was also assessed using the Modified scale for social
the existence of a relationship between IDA and den- level of families for usage in health research which
tal caries in early childhood and explore the role of was modified after the original scale of Fahmy and El-
other potential risk factors in development of both Sherbini specifically designed to capture all variables
conditions. A null hypothesis that no relationship linked to SES in Egyptian families.29 A 24-h dietary
exists between IDA and ECC was tested. recall was performed to capture detailed information
about children’s intake of foods and beverages in the
past 24 h to determine the quality of their diet. Based
METHODS
on total amounts of consumed carbohydrates, proteins
and fats, the caloric value of diet was calculated using
Ethical considerations
the ‘food calorie calculator’ of the US department of
A cross sectional study was conducted over 6 months Agriculture National Nutrient database.30 In order to
from February to August 2018 at the outpatient clinic describe diet quality as ‘good’, it needed to be both
of Ain Shams University (ASU) Paediatric Hospital, balanced and nutritious enough to ensure good health
Cairo, Egypt. Ethical approval was obtained from status and promote adequate growth and development
Research Ethics Committee of Faculty of Medicine, in children based on individual requirements.31 Diet
Ain Shams University (FMASU REC) in December was, thus, considered of good quality if it matched
2017 (no. MS44/2017). Parents or legal guardians recommended daily caloric intake based on age and
were informed about the purpose and the anticipated gender and included balanced amounts of macronutri-
benefits of the research and confidentiality of data ents: 60%–70% of total calories from carbohydrates,
was ensured. Prior to enrolment in the study, a signed 10%–15% from proteins and 20%–25% of total
2 © 2021 Australian Dental Association
 Dental caries and anaemia in children

Fig. 1 Study participants’ enrolment flow diagram.

calories from fat.32,33 On the other hand, diets which serum separator tube (SST). Blood samples were then
had higher or lower caloric value than required or analysed using a 5010 spectrophotometer (Roche
contained unbalanced macronutrients were considered diagnostics, GmbH, Sandhofer Strasse 116, D-68305
to be low quality. Mannheim). IDA in young children is defined as the
presence of ferritin level <12 mg/dL and haemoglobin
level <11 g/dL, in the absence of any condition that
Anthropometric measurements
can affect these findings.36
Anthropometric evaluation including weight in kilo-
grams (kg) and height in centimetres (cm) was per-
Dental examination
formed and data was plotted against Centre for
Disease Control and Prevention (CDC) sex-matched One trained and calibrated dentist carried out dental
charts. Body mass index (BMI) was calculated by examination for all enrolled children. All primary
dividing weight in kilograms (kg) by square of the teeth present in the oral cavity were assessed using the
height in metres (m2) and was plotted against the decayed, missing and filled teeth (dmft) index.37 Teeth
BMI CDC sex-matched chart.34 were assigned to the decayed (d), missing (m) or filled
(f) category; then, teeth within each of the index cate-
gories were added together to produce the total dmft
Laboratory investigations
score which indicated caries experience of the child.
Blood samples were collected by the nurse in-charge
under complete aseptic conditions. Complete Blood
Statistical analysis
Count (CBC) was performed using the automated
haematology analyser; Sysmex XT-1800i (Sysmex, Categorical data were presented as frequencies (n)
Kobe, Japan). Anaemia was classified according to the and percentages (%) and were analysed using chi
WHO criteria, and severity of anaemia was levelled square test. Quantitative data were explored for nor-
according to patients’ Hb levels (severe anaemia, mality using Kolmogorov–Smirnov and Shapiro–Wilk
Hb < 7.0 g/dL; moderate anaemia, Hb 7.0–8.9 g/dL; tests. Independent t test and Mann–Whitney U test
and mild anaemia, Hb 9.0–10.9 g/dL in children were used for analysis of parametric and non-para-
60 months or younger and Hb 9.0–11.4 g/dL in chil- metric data respectively. Pearson and spearman rank
dren above 60 months).35 Serum ferritin (30–400 ng/ order correlation coefficients were used to study the
mL), iron levels (males, 65–175 µg/dL) (females, 50– association between caries and all other study vari-
150 µg/dL) and total iron binding capacity (262– ables, and a multiple linear regression model was used
400 µg/dL) tests were done only for children with to predict caries incidence. The significance level was
microcytic hypochromic anaemia to confirm iron defi- set at P ≤ 0.05 for all tests. Statistical analysis was
ciency by withdrawing 2 mL of blood into gold-top performed with IBMâ SPSSâ (SPSS Inc., IBM
© 2021 Australian Dental Association 3
WE Mohamed et al.

Corporation, NY, USA) Statistics Version 25 for Win- show the distribution of demographic characteristics
dows. A receiver operating characteristic curve (ROC of participants in the two study groups. The mean age
curve) was used to assess the diagnostic ability of hae- values were (54.52  9.65) months and
moglobin level as a predictor for caries experience (49.80  7.95) for anaemic and non-anaemic chil-
and in the same manner the diagnostic ability of the dren, respectively. Demographic characteristics were
dmft index as a predictor for anaemia. similar in both groups, and the majority of the study
participants (>70%) were of low socio-economic
background.
RESULTS
Non-anaemic children had a significantly higher
A total of 80 children, of which 56% were male, were height percentile (33.25  19.57) 95% CI ( 24.3,
enrolled in the present study. Figure 1 and Table 1 3.89) (P = 0.005); however, no statistically

Table 1. Demographic characteristics of study participants (n = 80)

Anaemic Non-anaemic 95% CI of mean P value
difference

Lower Upper

Demographic data
Age by months (mean  SD) 49.80  7.95 54.52  9.65 2.15 1.98 0.062ns
Gender N (%)
Male 55.0% (22) 57.5% (23) – – 0.822ns
Female 45.0% (18) 42.5% (17) – –
Order of birth, N (%)
First 10.0% (4) 20.0% (8) – – 0.204ns
Second 30.0% (12) 37.5% (15) – –
Third 45.0% (18) 25.0% (10) – –
Fourth 5.0% (2) 12.5% (5) –
Fifth 5.0% (2) 5.0% (2) – –
Sixth 5.0% (2) 0% (0) – –
Socio-economic class, N (%)
Low 80.0% (32) 70.0% (28) – – 0.275ns
Medium 17.5% (7) 30.0% (12) – –
High 2.5% (1) 0% (0) – –
Mother’s education, N (%)
Mother is deceased 2.5% (1) 2.5% (1) – – 0.483ns
Read and write or illiterate not working 2.5% (1) 5.0% (2) – –
Read and write or illiterate working 10.0% (4) 2.5% (1) – –
Literate certificate not working 2.5% (1) 2.5% (1) –
Literate certificate working 0.0% 0 5.0% (2) –
Primary not working 17.5% (7) 20.0% (8) – –
Primary working 17.5% (7) 15.0% (6) –
Preparatory not working 25.0% (10) 20.0% (8) – –
Preparatory working 2.5% (1) 15.0% (6) – –
Secondary not working 10.0% (4) 7.5% (3) – –
Secondary working 5.0% (2) 2.5% (1) – –
University not working 5.0% (2) 0.0% (0) – –
University working 0.0% (0) 0.0% (0) – –
Postgraduate not working 0.0% (0) 2.5% (1) – –
Postgraduate working 0.0% (0) 0.0% (0) – –
Mother’s education score (mean  SD) 6.13  2.64 6.12  2.53 1.15 1.15 0.946ns
Per-capita income, N (%)
Not enough + loan not repeat 60.0% (24) 52.5% (21) – – 0.621ns
Not enough + big loan 30.0% (12) 40.0% (16) – –
Not enough + small loan 7.5% (3) 7.5% (3) – –
Enough only 2.5% (1) 0% (0) – –
Enough and saving 0% (0) 0% (0) – –
Per-capita income score (mean  SD) 3.05  1.50 3.10  1.28 0.67 0.57 0.628ns
Family size, N (%)
2 2.5% (1) 0% (0) – – 0.568ns
3 0% (0) 2.5% (1) –
4 5.0% (2) 12.5% (5) – –
5 20.0% (8) 25.0% (10) – –
6 50.0% (20) 35.0% (14) – –
7 15.0% (6) 12.5% (5) – –
8 7.5% (3) 10.0% (4) – –
9 0% (0) 2.5% (1) – –
Family size score (mean  SD) 5.90  1.13 5.82  1.32 0.47 0.62 0.538ns

ns, non-significant (P > 0.05).

4 © 2021 Australian Dental Association

 Dental caries and anaemia in children

significant difference was detected between both mean TIBC was 371.61  57.7 mcg/dL, and mean
groups regarding body weight percentile and BMI serum ferritin was 26.52  41.84 ng/mL.
(P = 0.128, 0.954), respectively. 82.5% and 67.5% of Using Pearson and Spearman rank order correlation
anaemic and non-anaemic children consumed poor coefficients revealed a statistically significant negative cor-
quality diet regarding quality of diet (P = 0.121), and relation between mean values of both dmft index and
no significant difference was found between both haemoglobin level (r = 0.454, P < 0.001) and MCH
groups regarding frequency of sugar intake level (r = 0.380, P = 0.001), while a positive statisti-
(P = 0.386) and teeth brushing (P = 0.080) (Table 2). cally significant correlation between dmft index and the
Table 3 shows that among anaemic children, 95% presence of anaemia was detected (r = 0.60, P < 0.001).
(38) had a mild form of anaemia; however, none of No significant correlation however was observed between
the participants was diagnosed as severely anaemic. caries experience and other independent covariables
The difference between the mean dmft score in the including age, socio-economic level indicators, height,
anaemic and the non-anaemic groups was statistically weight and BMI percentiles (P > 0.05). Table 4 shows
significant, being higher in the former (95% CI [2.45– that out of all potential covariables, only quality of diet
5.3]; P < 0.001). Additionally, mean serum iron val- and presence of anaemia were identified as potential pre-
ues in anaemic children was (35.91  14.45 mcg/dL), dictors of incidence of ECC among young children.

Table 2. Dietary, oral hygiene and anthropometric characteristics of study participants

Anaemic Non-anaemic 95% CI of mean difference P value

Quality of diet (%) N

High 17.5% (7) 32.5% (13) – – 0.121ns
Low 82.5% (33) 67.5% (27) – –
Frequency of sweets offering (%) N
Rarely 2.5% (0) 0% (0) – – 0.386ns
2–3 times weekly 10% (4) 2.5% (1)
Once daily 30% (12) 35% (14) – –
More than once daily 57.5% (23) 62.5% (25)
Frequency of teeth brushing (%) N
Never 72.5% (29) 67.5% (27) – – 0.080ns
Rarely (once weekly) 15% (6) 2.5% (1)
Sometimes (twice weekly or more) 2.5% (1) 17.5% (7) – –
Once daily 5% (2) 7.5% (3)
Twice daily 5% (2) 5% (2) – –
Body weight percentile 22.67  15.69 29.70  18.47 16.22 2.17 0.128ns
Height percentile 19.15  14.93 33.25  19.57 24.31 3.89 0.005*
Body mass index percentile 36.55  20.33 37.52  21.28 11.59 9.64 0.954ns

ns, non-significant (P > 0.05).

*Significant (P ≤ 0.05).

Table 3. Descriptive clinical parameters of study participants (n = 80)

Clinical parameter Anaemic Non- anaemic 95% CI of mean difference P value

Anaemia-related measures (mean  SD)

WBC 7.76  2.34 8.10  2.67 1.46 0.78 0.547ns
RBCs 4.47  0.51 4.74  0.42 0.48 0.06 0.012*
Platelet count 352.97  104.41 291.10  84.79 19.53 104.21 0.006*
Haemoglobin 10.27  0.75 12.29  0.90 2.40 1.65 <0.001*
Haematocrit 30.65  2.34 36.15  3.31 6.77 4.22 <0.001*
MCV 69.29  5.16 76.89  5.36 9.94 5.25 <0.001*
MCHC 33.56  2.21 34.14  2.32 1.59 0.43 0.258ns
MCH 23.27  2.63 26.20  1.67 3.91 1.95 <0.001*
RDW 20.79  44.32 15.77  2.46 18.99 8.95 <0.001*
Caries experience (mean  SD)
dmft index 4.37  4.44 0.50  0.90 2.45 5.30 <0.001*

MCH = mean corpascular haemoglobin; MCHC = mean corpascular haemoglobin concentration; MCV = mean corpascular volume;
RBCs = red blood cells; RDW = red cell distribution width; WBC = white blood cells.
ns, non-significant (P > 0.05).
*Significant (P ≤ 0.05).

© 2021 Australian Dental Association 5

WE Mohamed et al.

Table 4. Regression model predicting caries experi-

ence as measured by dmf index in both study groups
Independent Regression Standard t P value
variable(s) coefficients error value

Constant 79.87 65.23 1.22 0.226ns

Age (M) 0.01 0.05 0.24 0.808ns
Gender 0.16 0.87 0.18 0.856ns
Socio-economic 0.32 1.17 0.28 0.782ns
class
Order of birth 0.09 0.43 0.22 0.826ns
Mother’s education 0.10 0.19 0.53 0.597ns
Per-capita income 0.44 0.34 1.31 0.196ns
Family size 0.74 0.38 1.94 0.058ns
Quality of diet 3.08 1.25 2.46 0.017*
Frequency of 0.09 0.59 0.15 0.884
sweets offering
Frequency of teeth 0.88 0.50 1.74 0.087
brushing
Weight percentile 0.01 0.04 0.38 0.707ns
Height percentile 0.001 0.03 0.13 0.899ns
Body mass index 0.001 0.02 0.11 0.911ns
percentile
Haemoglobin 6.05 5.58 1.08 0.283ns Fig. 2 ROC curve for haemoglobin level as a predictor for caries pres-
Haematocrit 2.19 1.84 1.19 0.238ns ence
MCV 0.12 0.79 0.16 0.877ns
MCH 0.02 2.40 0.01 0.995ns
MCHC 2.13 1.97 1.08 0.284ns
Presence of 3.97 1.42 2.80 0.007*
anaemia

MCH = mean corpascular haemoglobin; MCHC = mean corpascu-

lar haemoglobin concentration; MCV = mean corpascular volume;
RBCs = red blood cells; RDW = red cell distribution width;
WBC = white blood cells.
ns, non-significant (P > 0.05).
*Significant (P ≤ 0.05).

The ROC curve analysis for haemoglobin level as

a predictor for caries incidence yielded an area
under the curve (AUC) of 0.814, 95% CI (0.711,
0.892) with sensitivity of 86.67% and specificity of
65.71%, for haemoglobin levels ≤11.6 (Fig. 2). On
the other hand, Fig. 3 depicts the ROC curve for
the diagnostic ability of caries experience (dmft in-
dex) in predicting anaemia with an AUC of 0.836,
95% CI (0.736, 0.909). Sensitivity and specificity
were of 75.00% and 90.00%, respectively for dmf Fig. 3 ROC curve for DMF index as a predictor for anaemia.
index greater than 1 (cut-off value) which was deter-
mined based on the corresponding highest Youden
index (0.65). In both curves, the large AUC is an the incidence of ECC. Regression analysis revealed
indicator of a good predictive performance of the that IDA could be a potential predictor for develop-
regression model. ment of ECC in young children even in its mild form.
In consistence, previous studies concluded that both
ID and IDA are associated with ECC or severe ECC
DISCUSSION
where children with low Hb levels38 and serum iron
In the current cross-sectional study, the level of caries levels39 were found to be more prone to develop den-
experience of children suffering from IDA was com- tal caries. Interestingly, in one study, it was
pared to that of non-anaemic children. Based on the found that resolution of IDA occurred simultaneously
study findings, the null hypothesis was rejected as a with treatment of dental caries even without adminis-
negative correlation was detected between haemoglo- tration of any iron supplementation.40 One recent
bin level and dental caries and in accordance; pres- ecologic study also revealed that, at country level,
ence of IDA was found to be positively correlated to prevalence of ECC was associated with anaemia in 3–
6 © 2021 Australian Dental Association
 Dental caries and anaemia in children

5 year olds; however, no country-level data were consistently associated with low prevalence of ECC.49
available on exact causes of anaemia.14 Angelopoulou et al., also, pointed out that preschool
On the other hand, Ramos-Gomez et al. indicated children from low-income households with high food
that no association existed between presence of anae- insecurity were at higher risk to develop ECC.46
mia and number of decayed and filled teeth. However, Contrarily, in the present study, quality of diet was
it is noteworthy that there was no clear reference to not related neither to presence of anaemia nor levels
iron deficiency as an etiological factor for anaemia in of haemoglobin. The relation between IDA and poor
this study.41 quality diet might have been masked because some
A plethora of explanations for the relationship staple foods and snacks in the Egyptian market are
between those two childhood health issues exists. One fortified with iron thus reducing the risk of iron defi-
study exploring the relationship between IDA and sus- ciency. On the other hand, some children with appar-
ceptibility to decay in a mouse model showed that ently good quality diets may be actually receiving less
anaemic mice were at a higher risk of developing deep than required daily intake of iron and other trace ele-
carious lesions. The authors assumed that iron is a ments. It is also noteworthy that the lack of associa-
protective factor against dental caries42 and attributed tion between IDA and poor diet could be attributed
this effect to the great affinity of iron to organic parts to inaccuracy of diet history acknowledging that sin-
of enamel and its ability to replace minerals lost dur- gle 24-h recall cannot account to day-to-day varia-
ing demineralization as previously suggested by tions in dietary habits and might underestimate the
Lacruz et al.43 It has also been suggested that IDA intake of some nutrients if irregularly consumed foods
might hinder oral defensive mechanisms such as saliva were inadvertently disregarded in history taking.
production and in one study treatment of IDA in chil- There is also some chance that legal guardians might
dren significantly improved the pH levels of saliva have reported some faulty information on their chil-
and its buffering capacity.44 dren’s dietary intake either due to some recall bias or
On the other hand, it has also been postulated that, to appear more socially acceptable.
in some instances, children might experience malnutri- In the literature, there is controversy over the rela-
tion due to dental pain during mastication which tionship between children’s nutritional status and car-
decreases appetite and limits dietary intake, including ies experience. In some studies, underweight and
iron enriched foods, such as red meat thus leading to stunted growths were associated with untreated dental
IDA particularly in presence of severe ECC or deep caries which has been attributed to difficulties in eat-
encountered carious lesions.40 Furthermore, according ing due to dental pain caused by caries experi-
to Bansal et al., in S-ECC, per se, the body’s inflam- ence.13,50 On the other hand, whereas a relationship
matory response caused by pulpal inflammation or was detected between obesity and ECC during
abscess formation might trigger a series of events that infancy,14 in other studies, no association existed
can ultimately inhibit erythropoiesis causing anae- between ECC and overweight among children in a
mia.45 similar age group.51 Noticeably, in studies relating
Additionally, the common risk factors between IDA obesity to ECC, the reason for this association was
and ECC such as inappropriate dietary practices, food linked to overconsumption of free sugars which nega-
insecurity and low SES might have also contributed to tively affects oral health and increases body weight. In
the existing association between the two condi- the current study, however, neither underweight nor
tions.46,47 In this context, this relationship could be overweight or obesity was found to be correlated to
described as bidirectional with the common factors ECC. A plausible explanation is that the majority of
mediating it. It is widely known that low-income fam- study participants with ECC had relatively low dmft
ilies tend to consume foods low in nutrients and high scores with no discernable effect on their growth pat-
in sugar and fat, due to lack of parental awareness terns.
and affordability of unhealthy snacks which render Although both IDA and stunting can occur as a
children more susceptible to dental caries.48 result of chronic malnutrition, it is still unclear
In our study, over 70% of study participants whether both conditions coexist or not. According to
belonged to a low social class and this might elucidate Gosdin et al., those two childhood issues are indepen-
why the majority of study participants (75%) con- dent such that addressing the underlying determinants
sumed poor quality diet with unbalanced amounts of of one condition would not necessarily improve the
macronutrients and/or unhealthy calorie intake. Based other.52 In the present study, anaemic children had
on the present study analysis, poor diet was a strong significantly lower height percentile than non-anaemic
predictor of ECC. In accordance, one study also children. This finding, however, could be, to some
revealed that the high scores for healthy eating index extent, misleading since only 10 anaemic and six non-
based on a 24-h food recall denoting adequate con- anaemic children were found to be stunted; hence, this
sumption of fruits, vegetables and dairy products were significant difference in mean values of height
© 2021 Australian Dental Association 7
WE Mohamed et al.

percentile of both groups could be due to the wide approval number MS44/2017 was obtained from
normal range of height in this age group.34 This is Research Ethics Committee of Faculty of Medicine in
further supported by absence of any significant differ- December 2017. This committee is organized and
ences in mean values of weight and BMI percentiles in operated according to guidelines of the International
the two studied groups. The mildness of the symp- Council on Harmonization (ICH) Anesthesiology and
toms of anaemia among over 90% of the anaemic the Islamic Organization for Medical Sciences
children explicates why none of the tested measure- (IOMS), the United States Office for Human Research
ments of nutritional status were associated with IDA. Protection and the United States Code of Federal Reg-
In consistence, the WHO report on prevalence of ulations and operates (Assurance no. FWA
anaemia showed that, globally, anaemia usually mani- 000017585).
fests in the mild form.53
Owing to the cross-sectional study design, a causal
relationship between IDA and ECC could not be CONSENT TO PARTICIPATE
inferred. Moreover, it is noteworthy that since all study A written consent was taken from children’s legal
participants were recruited from one public university guardians. All subjects were explained about the pur-
hospital, generalizability of the study findings is pose of the study.
implausible. Though WHO criteria for caries diagnosis
are predominantly used in epidemiological surveys,
however, DMF index takes into account only cavitated CONSENT FOR PUBLICATION
dentinal lesions while excluding any early carious Individuals were ensured that the information col-
lesions at the pre-cavitation stage,37 and thus ECC lected from them would be confidential and used only
might have been underestimated in the present study. for academic purpose.
On the other hand, it is worth mentioning that the den-
tal operator was blinded to any collected data pertinent
to medical status of children, clinical findings or labora- CONFLICT OF INTEREST
tory tests; thus, investigator bias was avoided. Authors declared any conflict of interest.
Longitudinal studies with larger representative sam-
ple are required for providing evidence on nature of
association between ECC and IDA, and the effect of FUNDING INFORMATION
common risk factors such as malnutrition and food This research did not receive any specific grant from
insecurity on the comorbidity of both conditions in funding agencies in the public, commercial or not-for-
childhood should be thoroughly investigated in differ- profit sectors.
ent populations. Future studies with more detailed
dietary intake assessment are also warranted to gener-
ate evidence on the role of diet in mediating the rela- AUTHORS CONTRIBUTIONS
tionship between dental caries and IDA in early W.E.I, R.K.A. and R.A.T conceived the ideas; S.H.K.
childhood. and M.H collected the data; R.K.A and R.A.T anal-
Based on our study findings, it is concluded that the ysed the data and drafted the manuscript. All other
incidence of ECC in young children appears to be authors revised and approved the submitted version.
associated with IDA even in its mildest form and good All authors agreed to be personally accountable for
quality diet with balanced amounts of macronutrients, authors’ own contributions.
and age-specific recommended energy intake is a cru-
cial factor in maintaining good oral health, reducing
caries risk in preschool children. DATA AVAILABILITY STATEMENT
All data generated or analysed during this study are
ACKNOWLEDGEMENT included in this published article. All data are avail-
able for sharing.
The authors express their utmost gratitude to all chil-
dren and their parents who agreed to be part of this
research. SUPPORTING INFORMATION
Additional Supporting Information may be found in
ETHICS APPROVAL the online version of this article:
This study was approved by the local research ethical Table S1. STROBE Statement—checklist of items
committee of Ain Shams University, Faculty of Medi- that should be included in reports of observational
cine in the Declaration of Helsinki 1964. Ethical studies
8 © 2021 Australian Dental Association
 Dental caries and anaemia in children

REFERENCES 18. Darmon N, Drewnowski A. Does social class predict diet qual-
ity? Am J Clin Nutr 2008;87:1107–1117.
1. Vos T, Abajobir AA, Abate KH, et al. Global, regional, and
national incidence, prevalence, and years lived with disability 19. Black MM, Quigg AM, Hurley KM, Pepper MR. Iron defi-
for 328 diseases and injuries for 195 countries, 1990–2016: a ciency and iron-deficiency anemia in the first two years of life:
systematic analysis for the Global Burden of Disease Study strategies to prevent loss of developmental potential. Nutr Rev
2016. Lancet 2016;390:1211–1259. 2011;69(Suppl. 1):S64–S70.

2. GBD 2017 Disease and Injury Incidence and Prevalence Collab- 20. Roganovic J, Starinac K. Iron deficiency anemia in children.
orators. Global, regional, and national incidence, prevalence, Curr Topics Anemia 2018;47:47–71.
and years lived with disability for 354 diseases and injuries for 21. Doom JR, Gunnar MR, Georgieff MK, Kroupina MG, Frenn
195 countries and territories, 1990–2017: a systematic analysis K, Fuglestad AJ. Beyond stimulation deprivation: iron defi-
for the Global Burden of Disease Study 2017 [published correc- ciency and cognitive deficits in post institutionalized children.
tion appears in Lancet. 2019 Jun 22; 393(10190):e44]. Lancet Child Dev 2014;85:1805–1812.
2018;392:1789–1858. 22. Murray-Kolb LE. Iron and brain functions. Curr Opin Clin
3. Chrisopoulos S, Harford JE, Ellershaw A. Oral health and den- Nutr Metab Care 2013;16:703–707.
tal care in Australia: key facts and figures 2015, Vol. 2. Can- 23. World Health Organization. Iron deficiency anemia; assess-
berra, ACT: Australian Institute of Health and Welfare and the ment, prevention, and control; a guide for programme man-
University of Adelaide, 2016:5. agers. Geneva, Switzerland: World Health Organization, 2001.
4. Awooda EM, Saeed SM, Elbasir EI. Caries prevalence among 24. Kumar V, Choundhry VP. Iron deficiency and infection. Indian
3–5 years old children in Khartoum State-Sudan. J Med Health J Pediatr 2010;77:789–793.
Sci 2013;3:42–44.
25. Paglia L, Scaglioni S, Torchia V, et al. Familial and dietary risk
5. Abbass MMS, Mahmoud SA, El Moshy S, et al. The prevalence factors in early childhood caries introduction. Eur J Paediatr
of dental caries among Egyptian children and adolescences and Dent 2016;17:93–99.
its association with age, socioeconomic status, dietary habits
and other risk factors. A cross-sectional study. F1000Research 26. Elalfy MS, Hamdy AM, Maksoud SS, Abdel Megeed RI. Pat-
2019;8:8. tern of milk feeding and family size as risk factors for iron defi-
ciency anemia among poor Egyptian infants 6 to 24 months
6. World Health Organization. Regional office for the eastern old. Nutr Res 2012;32:93–99.
Mediterranean. Egypt releases results of epidemiological study
on oral health status. 2014. Available at: http://www.emro. 27. von Elm E, Altman DG, Egger M, et al. The strengthening the
who.int/egy/egypt-events/results-of-epidemiological-study-on-ora reporting of observational studies in epidemiology (STROBE)
l-health-status-released.html statement: guidelines for reporting observational studies. Int J
Surg 2014;12:1495–1499.
7. Kolker JL, Yuan Y, Burt BA, et al. Dental caries and dietary
patterns in low-income African-American children. Paediatr 28. Schroth RJ, Levi J, Kliewer E, Friel J, Moffatt ME. Association
Dent 2007;29:257–264. between iron status, iron deficiency anaemia, and severe early
childhood caries: a case-control study. BMC Pediatr 2013;13:22.
8. Fisher-Owens SA, Gansky SA, Platt LJ, et al. Influences on chil-
dren’s oral health: a conceptual model. Pediatrics 2007;120: 29. Fahmy SI, Nofal LM, Shehata SF, El Kady HM, Ibrahim HK.
e510–e520. Updating indicators for scaling the socioeconomic level of fami-
lies for health research. J Egypt Public Health Assoc
9. Azevedo TD, Bezerra AC, de Toledo OA. Feeding habits and 2015;90:1–7.
severe early childhood caries in Brazilian preschool children.
Pediatr Dent. 2005;11:28–33. 30. The United States Department of Agriculture National Nutrient
Database. Calorie Control Council, Food Calorie Calculator.
10. Schwendicke F, D€orfer C, Schlattmann P, Foster Page L, Thom- Available at: https://caloriecontrol.org/healthy-weight-tool-kit/
son WM, Paris S. Socioeconomic inequality and caries: a sys- food-calorie-calculator
tematic review and meta-analysis. J Dent Res 2015;94:10–18.
31. Pelletier JE, Laska MN, MacLehose R, Nelson TF, Nanney
11. Finlayson TL, Siefert K, Ismail AI, Sohn W. Psychosocial fac- MS. Evidence-based policies on school nutrition and physical
tors and early childhood caries among low-income African- education: associations with state collaboration, obesity, and
American children in Detroit. Commun Dent Oral Epidemiol socio-economic indicators. Prev Med 2017;99:87–93.
2007;35:439–448.
32. Al-Salem A. Nutrition and caloric requirements for infants and
12. Alkarimi HA, Watt RG, Pikhart H, Sheiham A, Tsakos G. children. In: El-Salem AH, ed. An illustrated guide to pediatric
Dental caries and growth in school-age children. Pediatrics surgery. Cham: Springer, 2014.
2014;133:616–623.
33. Energy In: Recommended Food & Drink Amount for Children.
13. Dimaisip-Nabuab J, Duijster D, Benzian H, et al. Nutritional 2020. Available at: https://www.healthychildren.org/English/hea
status, dental caries and tooth eruption in children: a longitudi- lthy-living/nutrition/Pages/Energy-In-Recommended-Food-Drink-
nal study in Cambodia, Indonesia and Lao PDR. BMC Pediatr Amounts-for-Children.aspx
2018;18:300.
34. Centers for Disease Control and Prevention (CDC), National
14. Folayan MO, El Tantawi M, Schroth RJ, et al. Associations Center for Health Statistics. Clinical growth charts. 2017.
between early childhood caries, malnutrition and anemia: a glo- Available at: https://www.cdc.gov/growthcharts/clinical_charts.
bal perspective. BMC Nutr 2020;6:16. htm
15. GBD 2016 Disease and Injury Incidence and Prevalence Collabora- 35. World Health Organization. Serum ferritin concentrations for
tors. Global, regional, and national incidence, prevalence, and the assessment of iron status and iron deficiency in populations.
years lived with disability for 328 diseases and injuries for 195 Vitamin and Mineral Nutrition Information System. Geneva,
countries, 1990–2016: a systematic analysis for the Global Burden Switzerland: World Health Organization, 2011.
of Disease Study 2016 [published correction appears in Lancet.
2017 Oct 28;390(10106):e38]. Lancet 2017; 390:1211–1259. 36. Cappellini MD, Comin-Colet J, de Francisco A, et al.; IRON
CORE Group. Iron deficiency across chronic inflammatory con-
16. Ministry of Health and Population (Egypt), El-Zanaty and ditions: International expert opinion on definition, diagnosis,
Associates (Egypt), and ICF International. Egypt Demographic and management. Am J Hematol. 2017;92:1068–1078.
and Health Survey 2014. 2015.
37. World Health Organization. Assessment forms. In: Oral Health
17. Lopez A, Cacoub P, Macdougall IC, Peyrin-Biroulet L. Iron Surveys Basic Methods. 4th edn. Geneva, Switzerland.
deficiency anemia. Lancet 2016;387:907–916. 1997:21–50.

© 2021 Australian Dental Association 9

WE Mohamed et al.

38. Abdallah MA, Abed HH, Hamza G, Alsahafi EN. The associa- 47. Park K, Kersey M, Geppert J, Story M, Cutts D, Himes JH.
tion between dmft index and haemoglobin levels in 3–6 year- Household food insecurity is a risk factor for iron-
old Saudi children with anemia: a cross sectional study. J Tai- deficiency anaemia in a multi-ethnic, low-income sample of
bah Univ Med Sci 2016;11:72–76. infants and toddlers. Public Health Nutrition 2009;12:2120–
39. Tang R, Huang M, Huang S. Relationship between dental car- 2128.
ies status and anemia in children with severe early childhood 48. Mobley C, Marshall TA, Milgrom P, Coldwell SE. The contri-
caries. Kaohsiung J Med Sci 2013;29:330–336. bution of dietary factors to dental caries and disparities in car-
40. Shaoul R, Gaitini L, Kharouba J, Darawshi G, Maor I, Somri ies. Acad Pediatr 2009;9:410–414.
M. The association of childhood iron deficiency anemia with 49. Nunn ME, Braunstein NS, Krall Kaye EA, Dietrich T, Garcia
severe dental caries. Acta Paediatr 2012;101:e76–79. RI, Henshaw MM. Healthy eating index is a predictor of early
41. Ramos-Gomez FJ, Weintraub JA, Gansky SA, Hoover CI, childhood caries. J Dent Res 2009;88:361–366.
Featherstone J. Bacterial, behavioral and environmental factors 50. Sheiham A. Dental caries affects body weight, growth and
associated with early childhood caries. J Clin Pediatr Dent quality of life in pre-school children. Br Dent J 2006;201:
2002;26:165–173. 625–626.
42. Bahdila D, Markowitz K, Pawar S, Chavan K, Fine DH, Vel- 51. Macek MD, Mitola DJ. Exploring the association between
liyagounder K. The effect of iron deficiency anemia on experi- overweight and dental caries among US children. Pediatr Dent
mental dental caries in mice. Arch Oral Biol 2019;105:13–19. 2006;28:375–380.
43. Lacruz RS, Smith CE, Moffatt P, et al. Requirements for ion 52. Gosdin L, Martorell R, Bartolini RM, Mehta R, Srikantiah S,
and solute transport, and pH regulation during enamel matura- Young MF. The co-occurrence of anaemia and stunting in
tion. J Cell Physiol. 2012;227:1776–1785. young children. Matern Child Nutr 2018;14:e12597.
44. Mahantesha T, Reddy KM, Ellore V, et al. Evaluation and 53. WHO. The global prevalence of anemia in 2011. Geneva,
association of iron deficiency anemia with salivary pH and Switzerland: World Health Organization, 2015.
buffering capacity in children aged 6–12 years. Natl J Physiol
Pharm Pharmacol 2014;4:229–232.
Address for correspondence
45. Bansal K, Goyal M, Dhingra R. Association of severe early
childhood caries with iron deficiency anemia. J Indian Soc Rasha A. Thabet
Pedod Prev Dent 2016;34:36–42. Faculty of Medicine
46. Angelopoulou M, Shanti D, Gonzalez C, Love A, Chaffin J. Ain Shams University
Association of food insecurity with early childhood caries. J Cairo, Egypt
Public Health Dent 2019;79:102–108. https://doi.org/10.1111/
jphd.12299.
Email: rasha-thabet@hotmail.com

10 © 2021 Australian Dental Association