Protein-energy malnutrition (PEM)
remains a major public health problem in the world, particularly in developing
countries. According to the World Health Organization (WHO), PEM affects one-third of children around the world, and 43% of children in developing
countries (230 million), presenting a delay in staturoponderal growth [
The usual signs of children
malnutrition are clinical signs and anthropometric measures. However,
biological markers such as albumin, transthyretin, transferrin, and retinol binding
protein are also used for nutritional diagnosis and rehabilitation aftercare.
Several surveys have shown the relationship between clinical, anthropometric, or biological indicators and
mortality of children suffering from PEM in hospitals [
More recently
used markers like insulin-growth factor-I (IGF-I) used to measure the deficit
in growth hormone (GH), and the insulin growth factors binding proteins
(IGFBPs) also draw attention. Insulin-like growth factor-I (IGF-I) is single-chain
peptides of 7.5 kilodaltons (kDas). Her structure is similar to the IGF-II and proinsulin [
Many factors intervene in the regulation of the
IGF-I but the most important are growth hormone (GH), insulin, and nutritional
status [
Nutritional status plays an important role in
the regulation of the IGF-I. Adequate food intake is essential for maintaining
normal IGF-I and IGFBP-3 circulating rates in the serum[
The variations of serum IGF-I rates observed in
response to different nutritional states suggest that IGF-I may serve as a
marker for children nutritional state [
Only two surveys have been conducted on IGF-I and the nutritional rehabilitation among children under 5 years old but both were inconclusive because of low sample sizes [
The study of protocol was reviewed and approved by the Ethics Committee for Research in Health of Burkina Faso.
This study was conducted in two nutritional rehabilitation centres: (CREN) of the regional hospital (CHR) and the Persis medical centre (CM) of the city of Ouahigouya, located in the northern part of Burkina Faso.
All consecutively admitted patients with PEM should be included in the study. Among these patients, the criteria for selection were the age <60 months and the absence of known pathology like HIV, diabetes, congenital diseases, and tumours.
Upon admission, social and demographic characteristics (age, sex, and vaccination past records) were collected; weight and height were measured, and different clinical data were checked (presence of oedema, coloration of hair, splenomegaly, and hepatomegaly). Then, a capillary blood sample was taken from the child finger. The children were followed up and the anthropometric data and the capillary blood samples were again taken again on the 7th and the 14th days after admission.
The children admitted for malnutrition were well-cared for. They benefited from a free standard feeding which consisted of milk F75 for 7 days at 135 Kcal/Kg weight per day and milk F100 after the week at 100 Kcal/Kg weight per day. This posology was increased by 20 Kcal every 3 days until 200 Kcal/Kg per day, as necessary. In addition, the children received enriched pulp five times a day. A treatment for bacterial infections and malaria was available at any time if required.
A total of 68 children were recruited for the
study but only 59 were included because the ages of 9 children were unknown.
Table
Social and demographic characteristics of the household and the children admitted in two the nutritional rehabilitation centres in Burkina Faso.
Social and demographic characteristics | N | Mean |
---|---|---|
Gender of the children | ||
37 | 62.7 | |
22 | 37.3 | |
Mean age of children (months) | 59 | 14 |
Age categories of children (months) | ||
4 | 6.8 | |
6 | 10.2 | |
45 | 76.3 | |
4 | 6.8 | |
56 | 27.3 | |
6 | 10.7 | |
13 | 23.2 | |
15 | 26.8 | |
14 | 25.0 | |
8 | 14.3 | |
2 | 3.4 | |
57 | 96.6 | |
7 | 11.9 | |
52 | 88.1 | |
55 | 93.2 | |
4 | 6.8 | |
52 | 88.1 | |
7 | 11.9 |
Weight and height were determined on a Salter balance and the height
was rounded to the nearest centimetre. For children younger than 2 years,
height (length) was measured on a supine table as follows: an assistant held
the head against the headboard and another straightened the legs. For children
older than 2 years, a stadiometer was used. Nutritional status, expressed as weight for height (WHZ) and height for
age (HAZ), was standardised for age and sex using either the reference tables
from the Burkina Faso reference tables [
Blood was obtained by vein
puncture and 2 drops per circle were immediately collected on (free falling)
the filter paper; 2 circles per paper were systematically filled; the samples
were dried after 5–10 minutes at
ambient temperature (30–35
All filter paper samples were transferred for analyses to the Unit of Diabetes and Nutrition, Belgium. Samples were collected between October 2005 and May 2006.
We validated the methods of
determining the IGF-I levels from dried blood spots on filter paper on IGF-I
RIA, after separating the IGF-I from its binding proteins using Sep-Pack
chromatography [
The extraction recovery of IGF-I was
of
IGF-I absolute measurements were also standardised for age and sex,
and reported as IGF-I Z scores, using the reference values of IGF-I in children
from birth to the age of 5 in Burkina Faso [
Results are expressed as proportions for
discrete variables, as means and standard deviations (SDs) for continuous
variables with a normal distribution, and as geometric means with geometric
standard deviations for continuous variables with a log-normal distribution,
like IGF-I. Standardised values
are expressed as Z-scores and are reported as
mean
Two children (3.4%) were admitted to the Nutritional Rehabilitation Centre because of kwashiorkor, 55 children (93.2%) were admitted for marasmus, and two presented with both kwashiorkor and marasmus. One child died during the follow-up.
At the time of admission,
using international reference values as standards, 57 children (96.6%) had an
age- and sex-adjusted weight for height Z-score lower than
Out of the 57 children with a WHZ
When using Burkina
Faso
age and sex reference values for
standardising, 44% (26/59) of children had a WHZ
After 14 days of nutritional rehabilitation, 22 children (37%)
reached a WHZ ≥−2.0 according to international references, and 91% of these
children (20/22) also attained an IGF-I Z-score ≥−2.0. Using Burkina Faso data
as standards, the WHZ was ≥−2.0
in 80% (
Increase in IGF-I during nutritional rehabilitation in 59 children admitted for malnutrition in Burkina Faso.
During nutritional rehabilitation, IGF-I increased from 6.36 (1.40)
Table
Weight for height and IGF-I increase during nutritional rehabilitation, in 59 malnourished children in Burkina Faso.
Absolute measurements | ||||
Mean ± SD | [95% confidence interval] | |||
Admission | 59 | 59 | 1 | |
After 7 days | 59 | 59 | 1.59 [1.29; 1.89] | |
After 14 days | 59 | 59 | 2.52 [2.10; 2.94] | |
Age- and sex- | ||||
Mean
| ||||
Admission | 59 | |||
After 7 days | 59 | |||
After 14 days | 59 | |||
Age- and sex- | ||||
Mean ± SD | Mean ± SD | |||
Admission | 59 | 59 | ||
After 7 days | 59 | 59 | ||
After 14 days | 59 | 59 |
Reference values from Burkina Faso.
After 7 days of nutritional rehabilitation, IGF-I was multiplied by 1.587, as a significant increase of 58.7% on average. After 14 days, IGF-I increase was about 151.8% on average.
There was a significant increase in log-scaled IGF-I, as well as in
IGF-I Z-scores one week after admission (paired
The relationship between age- and
sex-adjusted IGF-I score and weight for height Z-score using the Burkina Faso
reference for standardisation is illustrated in Figure
Relationship between age- and sex-adjusted IGF-I Z-score and weight for height Z-score with Burkina Faso data as references, at admission and after 14 days of nutritional rehabilitation in 59-malnourished children from Burkina Faso.
Upon admission, the proportion of
children who had both WHZ of
Expressing the change in IGF-I as
a difference in IGF-I Z scores or expressing the change in IGF-I as a ratio
between IGF-I value after 14 days and IGF-I value upon admission, there was
significant correlation with the increase in weight for height Z-scores (
Relationship between the change in IGF-I expressed as an increase in Z-score (a) or as a ratio in absolute measurements (b) and the change in age- and sex-adjusted weight for height Z-score using Burkina Faso data as references, after 14 days of nutritional rehabilitation.
When using the international NCHS
references for standardisation, there was an even higher correlation between
changes in IGF-I and increases in weight for height Z-scores, with
The objective of this study was to assess the relationship between the IGF-I values and the nutritional status of children hospitalised for nutritional rehabilitation. The study also sought to determine IGF-I values as forecast markers of mortality. However, this last objective has not been achieved because the care given to children admitted in rehabilitation helped maintain a low mortality rate (1 in 68 children enrolled in the present study).
One of the limitations of our study is that the influence of factors
like infection was not taken in consideration. The acute or chronic inflammatory
status could interfere on the rate of IGF-I production. It was shown that in
the experimental model, the stimulation of an inflammatory status by injection
of endotoxin leads
to a reduction of IGF-I rates due to a resistance of the GH [
As far as the
evaluation of nutritional status is concerned, most of our patients suffered
from protein and energy malnutrition, with a few cases of kwashiorkor. Using
NCHS references, only two children had a WHZ ≥−2.0 at admission, and 73 %
presented severe malnutrition (WHZ
We observed variations of IGF-I with respect to the nutritional
rehabilitation. Low IGF-I values were observed in hospital children suffering
from protein and energy malnutrition [
The study conducted in Gabon by Zamboni et al. [
Palacio et al. [
Bhutta et al. [
Smith et al. [
The ability of IGF-I to follow variations of nutritional status shows that it is potentially a good clinical marker to follow nutritional rehabilitation in children with protein and energy malnutrition. The prognostic interest of IGF-I remains to be demonstrated by the implementation of studies which will measure the impact of IGF-I on the mortality of children with malnutrition in comparison with other markers of nutrition like albumin, prealbumin, and RBP. If the prognostic interest of IGF-I were proved, the use of IGF-I will be recommended. The experience shows that the cost of technology could be reduced quickly with the development of the research.
This research was supported by grants from Fonds de la Recherche Scientifique Médicale (convention FRSM 3.4561.04) and the Belgian Coopération Universitaire pour le Développement (CUD). The authors also thank Dr. Lassana Zalla of “Centre Medical Persis” and the paediatric staff of CHR of Ouahigouya.