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EXAMINATION OF URINARY IODINE STATUS FROM
A SAMPLE OF MALIAN ADOLESCENT GIRLS
Pawloski LR, Shier NW, Fernandez XE and PL Jamison
ABSTRACT
Iodine deficiency
disorders are common throughout the developing world, yet they are
considered one of the most preventable causes of mental retardation.
Iodine deficiency has tremendous consequences on women and girls
and can not only impair a woman's reproductive health, but it also
has serious consequences for a growing fetus. In pregnant women,
this deficiency can lead to congenital hypothyroidism in newborn
infants. Congenital hypothyroidism is a disorder associated with
a low IQ, deaf mutism, and neurological problems. Many studies have
revealed that iodine deficiency is common throughout West Africa.
While several of these studies have investigated the prevalence
of iodine deficiency among women in West Africa, few have examined
the problem among adolescent girls. Thus this study aimed to quantify
iodine levels in a representative sample of adolescent girls aged
10 to 15 years from the Segou Region of Mali, West Africa. Casual
urine samples were collected, and urinary iodine excretion was analyzed
using the Sandell-Kolthoff reaction. Clinical signs of iodine deficiency,
the presence or absence of goiters, were noted and ethnographic
interviews were conducted to examine dietary behaviors. Mean urinary
iodine excretion was 9.3 µg iodine/dl (95% CI 7.6-10.9). Forty
girls were iodine deficient (66.6%, 95% CI 53.3-78.3) of whom 19
(31.7% CI 20.3-45.0) showed moderate or severe deficiency. These
results show that the majority of these Malian adolescent girls
are at a mild to moderate risk for iodine deficiency, however no
statistically significant differences were found between girls from
the urban and rural communities. These findings suggest that not
only can iodine deficiency affect the individual health of these
girls, but iodine deficiency can have many ramifications concerning
the socioeconomic status of their communities. Because adolescent
girls are still growing and preparing to have children, these findings
have major implications for their health and the health for their
future children. These results provide one of the first analyses
concerning iodine deficiency among adolescent girls in Mali.
Key words -
Iodine deficiency, Mali, nutrition, adolescent girls
French
EXAMEN
DU NIVEAU D'IODE URINAIRE A PARTIR D'UN ECHANTILLON DE FILLES ADOLESCENTES
MALIENNES
RESUME
Contexte
: Les troubles dus à la carence en iode sont courants dans
le Tiers-monde. Chez les femmes, cette carence peut conduire à
un hypothyroïdisme congénital avec des troubles de croissance
chez les nouveaux-nés, associés à un bas Q
I et une surdité et aphonie. But : Cette étude avait
pour but d'évaluer de façon quantitative, le niveau
d'iode dans un échantillon représentatif de filles
âgées de 10 à 15 ans au Mali (Afrique de l'ouest).
Méthode : Des échantillons d'iode ont été
collectés dans la région de Ségou au Mali et
l'iode contenu dans l'urine a été analysé en
employant le réactif Sandell-Kolthoff. La présence
ou absence de goitre ont été notée et des enquêtes
ethnographiques conduites pour examiner leurs habitudes alimentaires.
Résultats: le taux moyen d'iode retrouvé dans les
urine étaient de 9,3mg iode /dl (95% IC 7.6 - 10, 9 ) quarante
filles avaient manifesté une déficience en iode (66,6%
, 95% IC 53,3-78,3) parmi lesquels dix neuf (31,7% IC 20,3 - 45.0)
ont manifesté une carence modérée ou sévère.
Discussion: Ces résultats démontrent que la majorité
de ces adolescentes maliennes courent un risque plus ou moins grand
de carence en iode. Ces résultats fournissent l'une des premières
analyses concernant la carence en iode chez les adolescentes du
Mali. Etant donné que les adolescentes sont en pleine croissance
et en âge de procréer, ces découvertes ont des
implications majeures pour leur santé et celle de leur futurs
enfants.
Mots clefs - carences en iode, le Mali, nutrition, adolescentes
IC : Intervalle de confiance
INTRODUCTION
As many as
800 million people worldwide have some form of iodine deficiency
[1]. Iodine deficiency is considered to be the most preventable
cause of mental retardation in the world. Iodine deficiency has
serious consequences on a growing fetus and can lead to a form of
mental retardation, known as congenital hypothyroidism. Congenital
hypothyroidism describes a condition in which the affected person
has an IQ as low as 20 and can also include deaf-mutism. It is estimated
that 20 million people have some degree of brain damage caused by
a lack of iodine in the diet during pregnancy [2]. Iodine is part
of the thyroid hormones and when deficient, the thyroid gland enlarges
to entrap as many particles of iodine as possible. This enlargement
causes a goiter, which is the most familiar and obvious sign of
iodine deficiency. Iodine has many crucial roles, including the
regulation of body temperature, reproduction, growth, the making
of blood cells, and nerve and muscle function [2].
Iodine deficiency
has a great impact on women of all ages. Primarily iodine deficiency
can affect a woman's reproductive health. Iodine deficiency occurs
more often in women in the form of goiter, and can first appear
during adolescence. Among women, iodine deficiency is most common
among adolescent girls and among pregnant women. Most researchers
suggest the greatest prevalence of iodine deficiency is due to the
greater need for iodine during growth, pregnancy, and lactation
[3]. This high prevalence of iodine deficiency among women of childbearing
years has great implications concerning the health of their children.
Thus an examination of adolescent girls who are often preparing
to have children or are already having children may provide some
clues concerning intervention methods.
It has been
estimated that in Africa alone, approximately 227 million people
are affected by iodine deficiency, with the majority of the cases
being found in western and Central Africa. Of these 227 million,
approximately 50 million have goiters, and nearly one million people
suffer from some form of congenital hypothyroidism [3]. While the
majority of iodine deficiency disorders have been seen in West and
Central Africa, there is a growing body of literature suggesting
severe problems related to iodine deficiency disorders in South
Africa [4,5] and in northern Africa [6].
Deficiencies
in iodine have also been correlated with reproductive failure and
problems related to pregnancy in West Africa among women of childbearing
years [7]. A recent study conducted in Cote d'Ivoire found that
iodine deficiency was more common among young women than any other
group [8]. The study also revealed that 68% of women of childbearing
age had goiters. Latapie, Clere, Beda et al. [9] have reported
that up to 80% of the women in the northwestern region of Cote d'Ivoire
have goiters, and a study by Asibey-Berko, Amoah, Addo et al.
[10] reported the prevalence of goiters among women and children
to be as high as 77% in rural eastern Ghana. Kouame, Bellis, Tebbi
et al. [11] revealed that women of childbearing years (15
to 45 years) had a higher susceptibility to developing iodine deficiency
disorders. Other studies throughout West Africa have revealed similar
findings [12,13].
In Mali, as
in many countries in sub-Saharan Africa, a woman's worth is often
based on the ability to have children. Thus, iodine deficiency not
only affects the physical health of a woman and her children, but
possibly her emotional health and social standing. Several studies
conducted throughout villages in Mali have indicated a high prevalence
of iodine deficiency, and endemic goiters are considered to be severe,
such that the prevalence of goiters affects between 16% to 90% of
some village populations [14,15].
It is believed
that the high prevalence of goiters in Mali is primarily due to
poor iodine intake. Foods commonly consumed throughout Mali have
been shown to be very low in iodine content [15]. For many economic
and cultural reasons, Malians rarely consume iodized salt even though
it is often readily available. While salt iodization is thought
to be one of the most common and effective means used to eliminate
iodine deficiency in the world [16], it has not appeared to have
as great an effect in Mali because the rate of iodine deficiency
still remains high despite some salt iodization programs. Reasons
that these programs have not been successful are most likely due
to economic and cultural factors. For example, many people in Mali
are unaware of such programs and do not want to buy the iodized
salt due to its cost. Further, because 90% of iodized salt is imported,
some associate iodized salt with western foods which are often avoided
[17]. To add to the difficulty in obtaining enough iodine in the
diet, Mali is an inland country and the soil content is low in iodine
[17] and because of its distance from the ocean, very little seafood
(often high in iodine) is consumed.
Most of the
research concerning iodine deficiency in Mali has been conducted
in the Bwa Region in eastern Mali and has examined prevalence of
goiter and congenital hypothyroidism. Other means to assess iodine
deficiency include biochemical assessment such as examining urinary
iodine concentration and determining serum thyroid hormones. Assessing
urinary iodine concentration is often preferred to collecting serum
thyroid hormones when conducting population studies in the field
because it is less expensive and is less complex. This article presents
one of the first analyses of urinary iodine concentration from adolescent
girls living in the Segou Region of Mali. This article will describe
the urinary iodine levels from a sample of Malian adolescent girls
living in an urban town, Segou, and a rural village, Dioro. It is
hypothesized here that:
1. The Malian
adolescent girls will exhibit mild to moderate indicators of iodine
deficiency.
2. The urban Malian adolescent girls will exhibit improved indicators
of iodine deficiency when compared to the rural Malian adolescent
girls.
STUDY SITE
AND SAMPLE POPULATION
Study Site
The convenience
sample of adolescent girls ages 10 to 15 years (n = 60) was recruited
from schools in an urban town, Segou (n=29), and a rural village,
Dioro (n=31). Both of the research sites are located within the
Segou administrative region. The Segou Region (see Figure I) is
located approximately 200 kilometers north of the capital, Bamako,
and is situated primarily along the Niger River.
The Segou Region
was chosen because it is fairly homogeneous in its geography, environment,
ethnic population, language, and religious affiliation. Two sites
are compared here, the city of Segou and the village of Dioro.
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Fig. 1: Map of Mali showing the
Egou Region
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The
city of Segou represents the largest and wealthiest city in the
Segou Region. Segou serves as a major trading town between the northern
cities and Bamako. The main industry there is a textile factory
and a military base. The town is equipped with electricity and running
water, yet most people cannot afford these services, and use community
pumps for water. There is also a maternity, a hospital, and several
pharmacies in town. Bambara is the most prevalent ethnicity (80%)
and is the major language spoken in Segou.
Dioro, the
rural community, is much poorer than Segou and has little industry
or business. Most villagers are subsistence farmers. Dioro has fewer
schools and health centers and does not have electricity or running
water. Ethnically, Dioro is also predominantly Bambara. From discussions
with local government officials, people living in Dioro and the
town of Segou display many similar cultural characteristics, particularly
pertaining to eating and working patterns. Segou exhibits a much
higher socioeconomic status as evidenced by its level of industrial
development, schools, access to electricity and running water, and
health facilities [17].
Sample Population
Concerning
dietary practices, ethnographic data revealed that most girls from
both Dioro and Segou eat three meals a day. Breakfast in Segou usually
consisted of a piece of bread, or a millet porridge mixed with sour
milk or pancakes made of millet, and coffee. In Dioro, girls mostly
reported just eating the porridge. A typical lunch or dinner meal
included one small piece of meat, fish, or chicken that was combined
in a sauce of a beef based broth (using bouillon cube and water)
with baobab leaves or a few boiled vegetables (including carrots,
tomatoes, okra, eggplant, onions, and cabbage). The sauce also often
included oil, salt, and hot peppers. The sauce was then poured onto
a large serving of thick millet porridge or rice. In the villages,
dinners and breakfast were often leftovers from the previous day's
lunch or dinner. Rice, which is more expensive than millet, was
more commonly consumed in wealthier families. Further, while salt
is a common ingredient added to the rice and sauce, no families
reported using iodized salt in the preparation of foods [17]. Iodized
salt is considerably more expensive than the non-iodized salt, because
non-iodized salt is widely available in Mali due to the large numbers
of local salt mines. The iodized salt is primarily imported from
Senegal and Russia.
In Mali, men
and women eat separately. They each eat from separate common pots
and children will usually eat with the women. Food is most often
eaten using the hands in which the rice and sauce is rolled into
a small ball in the palm of the hand and eaten. Water is also consumed,
but usually after the meal. Adolescent girls are often responsible
for the preparation of meals and gain additional cooking responsibilities
as they grow. Because of the style of eating, it is very difficult
to conduct a dietary recall because the researcher cannot measure
how much food has been placed on one plate. Further, it is even
more difficult to assess diets among adolescent girls because girls
tend to snack more frequently as they gain cooking responsibilities.
However, Pawloski [17] found a sample of girls from the Segou Region
to consume a mean of 2500 kilocalories per day.
One other factor
that affects the nutrient consumption of adolescent girls in Mali
concerns their energy expenditure. Adolescent girls have tremendous
amounts of responsibilities that range from gathering wood, to collecting
water, to cooking, cleaning, and taking care of children. These
workloads in combination with their requirements for growth and
development, greatly increase their nutrient needs. Factors that
have been shown to decrease their responsibilities include the presence
of servants in the family and the ability to attend school [17].
Anthropometric
data is presented here to show that according to the World Health
Association guidelines [18,19], these girls are considered to be
mildly to moderately malnourished, and thus are potentially at risk
of micronutrient deficiencies. Earlier research in this community
revealed that girls living in the Segou Region have mean z-scores
that are below the mean reference population for both height (Mean
Height-for-Age Z-score = -.79) and weight (Mean Weight-for-Age Z-score
= -1.09). Further, there were statistically significant differences
between the urban and rural communities for both height and weight,
so that the urban girls were significantly taller and fatter than
the rural girls (p < .05 and p< .01 respectively) [19]. "Z"
scores are presented here because malnutrition is often defined
in terms of z-scores. The value of "z" is the value of
the score on the standard normal distribution which is based on
samples of healthy well-nourished children. This data again indicate
that these girls suffer from both chronic and acute malnutrition
[18,19].
MATERIALS
AND METHODS
Data Collection
Casual urine
samples were taken from 60 adolescent girls ages 10 to 15 years.
Dunn [20] recommends that at least 40 subjects be obtained to determine
the mean concentration of urinary iodine in a certain region, thus
a sample size of 60 was considered adequate to show a deficiency
among adolescent girls in this setting (Segou Region of Mali). Because
subjects came from both urban and rural settings, comparisons were
made between these two groups.
The conditions
regarding the urine collection were difficult. For example, no bathrooms
were available in the schools, thus make-shift partitions were set
up to give girls privacy. The participants were explained the nature
of the study and they agreed to participate; however, many girls
found it completely absurd and funny that the researcher would want
a small sample of their urine, but they would in no way agree to
donate a 24-hour sample. Thus while a 24-hour urine collection is
more reliable, this was not feasible in such field conditions because
girls were not willing to participate in such an intensive data
collection procedure. Further, the data was collected during the
harvest season when girls have many added responsibilities, and
would not have been able to provide a 24-hour urine sample. However,
casual samples have been shown to accurately reflect 24-hour collections
in population studies [21].
Urine samples
were refrigerated and then analyzed at the Nutrition Laboratory
at Indiana University, Bloomington, U.S.A. The method used was described
by Dunn, Crutchfield, Gutekunst et al. [22] and was adapted
and modified from Wawschinek, Eber, Petek et al. [23]. This
method has been described as simple, inexpensive, and effective
for assessing urinary iodine concentration [24]. It is highly recommended
for the detection of iodine deficiency in the field, particularly
when compared to the expensive costs and difficulties of collecting
serum thyroid hormones and clinical assessment of thyroid size.
These other methods require more expensive equipment and skilled
technicians. This method was chosen to be done in the United States
because the basic equipment was available in the United States and
not in Segou, Mali. With future funding, we hope to bring this equipment
to Mali and provide local training regarding iodine deficiency assessment
and prevention.
Dunn's method
incorporates the Sandell-Kolthoff reaction in which urine is digested
first with chloric acid [22]. The concentration of iodine is then
determined from its catalytic reduction of ceric ammonium sulfate
in the presence of arsenious acid. A simple spectrophotometer is
used to examine the reduction of ceric ammonium sulfate such that
the disappearance of the yellow color is proportional to the amount
of iodine. A standard curve relating iodine concentration to color
was first made from known standards in order to extrapolate the
concentration of iodine [22]. The concentration of iodine is recorded
in micrograms of iodine per deciliter. While standard purchased
samples were used to determine iodine concentration, concentration
of iodine was also collected and analyzed from a small sample of
Indiana University students to ensure the reliability of the laboratory
procedure.
The presence
of goiters was also noted using the classification system endorsed
by the World Health Organization and the International Council for
Control of Iodine Deficiency Disorders [20]. Dunn and VanderHaar
[20] have defined 5 grades ranging from grade 0 (no goiter) to grade
3, in which the thyroid is greatly enlarged and is visible from
about 10 meters. Grade 1A is similar to grade 1B, which indicates
that the thyroid is enlarged and visible with the head is tilted
back. However in grade 1A, the goiter cannot be seen, but can be
felt when palpated [20].
Permission
and proper research clearances were obtained prior to our visits
from officials in Bamako, Mali and a Human Subjects clearance was
obtained from the Indiana University Human Subjects Committee.
RESULTS
For the total
sample (n=60), Table 1 indicates the mean urinary iodine excretion
was 9.3 µg iodine/dl (95% CI 7.6-10.9). For the rural sample
(n=31), the mean urinary iodine excretion was 9.1 µg iodine/dl
(95% CI 6.8-11.4) and for the urban sample (n=29), the mean urinary
iodine excretion was 9.5 µg iodine/dl (95% CI 6.7-12.2). While
the urban sample had a mean urinary iodine excretion that was higher
than the rural sample, oneway analysis of variance revealed this
relationship was not statistically significant (p = 0.83). No differences
were found between the urban and rural samples. Yet, there was a
trend towards lower urinary iodine in the rural sample. Also, observations
for clinical signs of iodine deficiency revealed that three rural
girls showed small goiterous growths of Grade 1B using the classification
system endorsed by the World Health Organization and the International
Council for Control of Iodine Deficiency Disorders, whereas no goiters
were observed in the urban girls. However, the study lacked the
statistical power to detect anything other than very large differences.
Given the results, the study has at most a 22% power to detect mean
differences of 2 micrograms and a 43% power to detect differences
of 3 micrograms between groups.
Normal values
for iodine are greater than 10 µg iodine/dl, while a range
of 5-9.9 µg iodine/dl suggests a mild deficiency, 2 - 4.9
µg iodine/dl indicates a moderate deficiency, and values less
than 2.0 µg iodine/dl suggest a severe deficiency in which
the need for intervention is critical [3]. Table 2 demonstrates
that 33.3% (95% CI 21.7-46.7) of the girls had normal amounts of
iodine. However, 35% (95% CI 23.1-48.4) exhibited a mild deficiency,
26.7% (95% CI 16.1-39.7) were shown to be moderately deficient and
5% (95% CI 1.0- 14.6) were severely deficient.
DISCUSSION
The results
indicate that iodine deficiency does occur among both urban and
rural adolescent girls in the Segou Region of Mali. While very few
of these girls exhibit any clinical symptoms of iodine deficiency,
the urinary iodine analyses suggest that many girls are at risk
and are in need of intervention. Although rural girls have overall
lower urinary iodine values than their urban counterparts, the difference
between the two groups was not statistically significant. Perhaps,
while socioeconomic indicators are greater in the urban area than
in the rural area, this data might suggest that access to and consumption
of iodine in both the rural and urban areas are quite similar and
are not as affected by economic differences between the rural and
urban areas. Thus, this data may suggest that in Mali, socioeconomic
status does not have a great bearing on iodine status. Further,
perhaps the comparisons between the urban and rural samples suggest
that the two communities are much more similar regarding environmental
conditions and traditional eating patterns. While Segou is a larger
and wealthier community than Dioro, both towns lie next to the Niger
River. All of the girls in the study attended school and reported
having similar diets and responsibilities [17].
Pawloski [17,
19] reported recently that the adolescent girls living in an urban
setting in Mali were taller and heavier, fatter and more muscular
than their counterparts living in the rural setting, and these differences
were shown to be statistically significantly different. Thus, it
was hypothesized in this paper, that urban girls would also show
improved indicators of iodine status. While perhaps girls living
in the urban environment consume nutrients which more greatly affect
growth and development, both urban and rural environments appear
to be similarly affected by deficiency in iodine.
Earlier studies
have shown a high incidence of iodine deficiency in Mali, but none
have examined adolescent girls. This data suggests that these girls
are at risk from complications of iodine deficiency and because
they are preparing for marriage and childbirth, their future children
may also be at great risk for congenital hypothyroidism. Congenital
hypothyroidism is not uncommon in Mali and one study has shown it
to have a prevalence of close to 1.2% in eastern Mali [14]. Adolescent
girls are even at greater risk because they are still growing and
have therefore greater iodine needs.
Malians in
general are at high risk of iodine deficiency because of the lack
of iodized salt in the diet, low amounts of iodine in the soil,
and low intake of sea fish. Malian adolescent girls primarily eat
a meal that is high in rice and millet with a small amount of sauce
that includes boiled vegetables, and small pieces of meat. While
salt is added to most foods during preparation, it is rarely iodized.
Malians also commonly add bouillon cubes (Maggi Cube) to prepare
sauces. Although these cubes do not contain iodine, many relief
workers have suggested that because these are so commonly consumed,
iodizing Maggi Cubes could have a significant effect on the occurrence
of iodine deficiency.
In most urban
areas in the Segou Region, iodized salt is readily available due
to recent governmental efforts to try to reduce the prevalence of
iodine deficiency. Ethnographic evidence revealed that many people
did not want to buy iodized salt because not only was it too expensive,
but many people viewed it as a kind of "western" food
and felt it was unnecessary. The price of iodized salt in Mali is
approximately $4.00 US per kg and the price of uniodized salt in
Mali is approximately $.50 US per kg [12, 13]. Further, in villages,
salt was often traded for other items rather than purchased. Many
Malians said that westerners eat over-priced foods that are not
necessary to live, and thus they avoided them. Interestingly enough,
iodized salt is manufactured in nearby Senegal and a new plant is
being constructed in Bamako, the capital, to iodize salt, however
iodized salt still continues to be imported.
Other factors
that contributed to people not consuming iodized salt included the
lack of education. It was observed that many projects had been conducted
all over Mali which ranged from cost sales of iodized salts from
United States Peace Corps volunteers to non governmental organization
education programs to government sponsored oral supplementation
programs. Further UNICEF is providing education programs regarding
iodine deficiency prevention [13]. While most of these programs
do give instruction on the importance of consuming iodized salts,
many people in Segou and in surrounding villages were unaware of
the connection between goiters, cretinism and iodine. Further, some
participants revealed that many people with goiters did not want
to talk about iodine deficiency or participate in studies which
examine the goiters because they were embarrassed by and ashamed
of them and did not want to draw attention to them.
Other than
salt fortification and nutrition education programs, several other
kinds of intervention programs have been set-up throughout Africa
to try to reduce the prevalence of iodine deficiency. One program
that has shown success in the Central African Republic has been
the combination of an iodine education project with the iodinization
of well water within the communities [25]. Even with these various
fortification programs, there are risks of over-consumption of iodine
leading to hyperthyroidism if these programs are not safely monitored
[26]. Further, some studies have shown that iron deficiency limits
the successfulness of these intervention programs because iron deficiency
can affect thyroid metabolism [27].
It is important
to recognize that while most of these girls are mildly deficient,
they and their future children, are still at risk for health complications
related to iodine deficiency disorders. In Mali, having healthy
children is an important part of life because children contribute
tremendously to the domestic needs of a household. A woman who has
few children has more domestic responsibilities. More importantly,
however, a woman's worth is often based on the fact that she can
bear healthy children. A woman who has no children may be divorced
and may have no support system later on in life [28].
Iodine deficiency,
as with malnutrition in general, can also play a large role concerning
the socioeconomic situation of a community. Studies such as those
conducted by Greene [29] in Ecuador showed villages which reported
low frequencies of iodine deficiency were much better off economically
than when compared to villages reporting high rates of iodine deficiency.
Greene [29] also showed that even mild deficiencies of iodine affect
quality of life within a community and ultimately the economic success
of a community.
Dunn [3] reported that iodine deficiency can affect the people's
work output because those that have iodine deficiency are less active
and mentally slower. These effects can cause a shift in the labor
force, in which there are fewer individuals available to do work.
Dunn [3] presented data from the effects of an iodine deficiency
intervention in China and revealed that ten years after effective
iodine supplementation, the community intervened had a dramatic
decrease in school failure rate, and the per capita income raised
from $43 U.S. to $550 U.S. [3].
Thus, not only
does iodine deficiency affect the individual health of these Malian
adolescent girls, but iodine deficiency can have many ramifications
concerning the socioeconomic status of their communities. Because
iodine deficiency can affect mental processes, these girls are at
a greater risk of doing poorly in school. Further, these communities
rely tremendously on the labor from adolescent girls. In Africa,
women do approximately 90% of the agricultural labor requirements,
and in Mali, girls participate as greatly as adult women. Thus iodine
deficiency may impact agricultural production as well.
This data reveals
that iodine deficiency disorders do exist among adolescent girls
in the Segou Region of Mali. Further, they appear to impact on both
urban and rural areas, and do not more greatly affect rural girls
as originally hypothesized. Because adolescents are still growing
and preparing to have children, this micronutrient deficiency is
not only a concern among these girls, but for the health of their
future children. This research is also critical to the understanding
that interventions to reduce the prevalence of iodine deficiency
disorders should not only involve the adult community but also include
adolescents.
CONCLUSION
The data presented
in this study reveals that Malian adolescent girls from the Segou
Region are at risk from iodine deficiency. The urinary iodine excretion
data suggested about one-third of these girls are mildly at risk
and one-third are at moderate to severe risk. Because they are preparing
for marriage and childbirth, lack of iodine can put their future
unborn children at great risk for congenital hypothyroidism. Although
iodine deficiency is unheard of in the developed world because of
the success of iodized salt programs, programs such as these have
not been as effective in Mali. It is believed that many factors
contribute to iodine deficiency in Mali including poor iodine content
in foods and lack of acceptance of iodized salt.
Thus these results suggest that there is a need to provide intervention
programs that include adolescent girls. Education programs are needed
to make people aware of the causes and problems associated with
goiters and congenital hypothyroidism. Further, while iodized salt
programs have not been successful throughout the Segou Region, perhaps
other methods such as iodine tablets, iodization of water, or fortification
of commonly used foods, like Maggi Cubes may provide a means to
reduce the prevalence of iodine deficiency.
ACKNOWLEDGEMENTS
This study
was performed as part of research for a PhD dissertation in the
Department of Anthropology at Indiana University. This work was
supported by a Fulbright IIE grant as well as a grant-in-aid from
the Research and University Graduate School at Indiana University.
I would like to thank the co-authors for their collaboration and
input. Finally, I am grateful to Moussa Diarra, my research assistant
in Mali and to Dr. Alyce Fly for helping to collect the control
urine samples from Indiana University students.
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Table
1
Mean urinary iodine concentrations of Malian adolescent
girls
|
 |
|
(Urban/Rural:
Oneway ANOVA, F = .049, p = .826
|
|
Table
2
Frequency of urinary iodine excretion at each stage of
severity
|
 |
|
(*Dunn
JT, Crtuchfield HE, Guteknst R and AD Dunn Two simple
methods for measuring iodine in urine. Thyroid 1993;3:119-123)
|
Lisa R.
Pawloski [Corresponding author]
Assistant Professor
College of Nursing and Health Sciences - MSN 3C4
George Mason University, 4400 University Dr. Fairfax
VA 22030,
USA
Email: lpawlosk@gmu.edu
Nathan W.
Shier
Associate Professor
Department of Applied Health Science
Indiana University
1025 E. 7th Street, HPER Bldg. 116
Indiana University, Bloomington, IN 47405, USA
Email: shier@indiana.edu
Xinia E.
Fernandez
Department
of Applied Health Science
Indiana University
1025 E. 7th Street, HPER Bldg. 116
Indiana University, Bloomington, IN 47405, USA
Email: xfernand@indiana.edu
Paul L.
Jamison
Professor
Department of Anthropology
701 E. Kirkwood Dr., Student Bldg. 130
Indiana University, Bloomington, IN 47405, USA
Email: jamison@indiana.edu
|