Prevalence of Stunting and Associated Factors among Children Aged 06-59 Months In Southwest Ethiopia : A Cross-Sectional Study

The term malnutrition generally refers both to under nutrition and over nutrition, but in this situation we use the term to refer solely to a deficiency of nutrition. Many factors can cause malnutrition, most of which relate to poor diet or severe and repeated infections, particularly in underprivileged populations. Inadequate diet and disease, in turn, are closely linked to the general standard of living, the environmental conditions, and whether a population is able to meet its basic needs such as food, housing and health care [1, 2].

Improving overall nutritional status throughout the life cycle is crucial to maternal and child health.Women who become malnourished during pregnancy and children who fail to grow and develop normally due to malnutrition at any time during their life, including during fetal development, are at increased risk of prenatal problems, increased susceptibility to infections, slowed recovery from illness, and possibly death.Improving maternal nutrition is crucial for improving children's health.The poor nutritional status of children and women has been a serious problem in Ethiopia for many years [14].
Even though Child malnutrition remains one of the most important concerns of the world including Ethiopian government only few studies done at national and regional levels, the prevalence and risk factors at sub-regional or community level have been insufficiently emphasized, which makes interventions difficult in such circumstances .For example, according to the 2011 DHS, the prevalence of stunted, wasted and underweight children in the region (SNNPR) was 44.1%, 7.6% and 28.3%, respectively, indicating that there are several zones and districts with higher prevalence rates than the regional average [9].
Having this in mind, the aim of our study was to determine the magnitude of chronic malnutrition and identify the major factors associated with it that will guide a good intervention approach to halt the problem.

Methodology Study Design, area and period
A community based cross-sectional study was conducted to assess the prevalence of stunting among under five children.The study was conducted at shey Bench district from April 1 to May 30, 2016.shey bench is located about 593 Kilo meter from Addis Ababa (capital city of Ethiopia) in southwest direction.Based on central statistical agency in 2010 this town has an estimated total population of 27, 975 of which 13002 men, 14973 women and 4210 under five children.

Source Population and sampling
The Source population was children (06-59 months) of age who lived with their mother's or caregivers in the house holds of Shay Bench district.The Study populations were children 06-59 months of age who lived with their mothers or care givers in the sampled kebeles of Shay Bench district.All children among age of 06-59 months in Shay Bench town were included and Children who are critically sick and that makes difficult to take anthropometric measurement were excluded.For sample size calculation we use single population proportion formula considering the following assumptions: 95% confidence level, proportion (p) of stunting 35% studied in Benchi Maji zone and 5% margin of error (d).
ni= (1.96) 2 (0.35) (0.65)/ (0.05) 2 =350.Since the source population is 4210 which is less than 10,000 we need to adjust the sample size.Final (n) =ni/1+ni/N, Where N is the source population.n=350/1+350/4210 =324.By adding 10 % non respondent rate the final required sample size was 356.Lists of children aged between 06 and 59 months along with their mothers residing in all kebeles (the smallest administrative unit) of shey bench district were taken from health extension workers and then sampling frame was constructed for each kebeles.Simple random sampling technique was used to select a sample of 356 children proportionally from all kebeles by using lottery method.

Data Collection Procedure and Tools
For a Socio economic and demographic, Dietary, Environmental and Health care characteristics data was collected face to face interviewing mothers/care takers by using a structured questionnaire which is adopted from other similar studies.Anthropometric Measurements was collected using the procedure stipulated by the WHO (1995) for taking Anthropometric measurements.Adherence to this procedure was ensured.The protocol used was as follow.
Length: -Length measurement for children less than 24 months was made by laying flat on the length board.The sliding piece was placed at the edge of the bare feet and at the head (with crushing of the hair) touched the other end of the measuring device.
Height: -Height was taken in a standing position for children greater than 24 months .The measurement was taken to the nearest 0.1 cm using short height measuring board.

Operational Definition
Stunting was defined as HAZ< minus two Z-score based on WHO reference group.

Data Quality Assurance, Processing and Analysis
Before the actual data entry was started completeness, accuracy, and consistency of the collected data were checked on daily basis during data collection by the principal investigators.Data were entered, cleaned and analyzed by using SPSS version 20.0 statistical software.Descriptive statistics were done and presented by using tables and figures.Bivariate logistic regression analysis was used to assess the association between each independent variable with the dependent variables.Those variables that have been associated with the dependent variables at p-value of less than 0.2 were fitted in to multivariate logistic regression models to control the effects of confounding.Those variables having p-value of less than 0.05 was considered as significant.

Characteristics of the sample
A total of 324 children aged 06 to 59 months along with their mothers/care givers were enrolled in the study, with a response rate of 91 %.For all parental and children socio-demographic

Environmental, Health care and children feeding Characteristics of children and parents
From the total households 150(46.3%) of them had water source from public pipe, 306(94.4%)households have Functional toilet.Of the total children mothers 157(48.5%)had ANC visit of 2-3 times during their pregnancy, 265 (81.8 %) give birth at health institutions and 100(30.9%) of the mothers had no post natal care visit.From the total study participants 192(59.9%) of children had birth weight of 2.5-4 kilogram and 123 (38%) of children were in the second and third birth order.Among study participants 263(81.2%) of children were fully immunized and 69(21.3%)had fever, 81 (25%) had diarrhea in the past two weeks.
Among 324 children 321(99.1%)were breast fed, 312(96.3%)initiated to breast feed within one hour of delivery and 84 (25.9 %) of children had started complementary feeding at age of 6 months.For all environmental, health care and child feeding characteristics see table 2 below.

Prevalence of stunting among 06-59 months children
Based on WHO criteria the prevalence of stunting among children of 6-59 months in shey bench district is 33.3%.

Factors associated with stunting among 6-59 months children
Multivariate logistic regression analysis revealed that age of the child, preceding birth interval and age at which complementary feeding started were associated with stunting at p value <0.05.Children aged 12-24months were about 0.06 times less likely to be affected by stunting [AOR0.06;95CI (0.02-0.08)] and children above 24 months were 0.12 times less likely to be affected by stunting [AOR0.12 ; 95 % CI(0.03-0.56)]compared to children aged 6-11 months.
Children who had born less than 2 years interval were 2.31 times more likely to be affected by chronic malnutrition [AOR 2.31; 95 % CI (1.43-5.08)] as compared with children who had born more than 2 years interval.
Children who had started complementary feeding at less than six months or above six months were 3.78 [AOR 3.78; 95 %CI (1.39-5.25)]times more likely to be affected by stunting than those started complementary feeding at the age of 6 months.

Discussion
Nutritional Stunting, which is height for age below that expected on the basis of International growth reference, is a very serious type of malnutrition in that it develops slowly through time before it is evident.
This study intended to assess the prevalence of stunting and associated factors among 6-59 months children in shey bench district.Based on this study the prevalence of stunting was 33.3%; 95%CI.This study was in line with the study conducted in Mizan Aman town, 34.5%, in Hosanna (35.4%) and Bangladesh (34.4%) [15][16][17].the prevalence is higher than the study conducted by Ethiopian Base line survey 2010, (25%) [8] And the study conducted in Somali region (17.2%)[18].However, the prevalence of stunting in the study area was lower than the study conducted in north shoa (47.6 %), in Lalibela (47.3%) and Vietnam (44.3%) [19][20][21].the prevalence of stunting in the study Note: All of the characteristics related to health care and feeding practice is concerning to index child.
area was also lower than a research conducted in Bule hora, southern Ethiopia (47.6%) [22].
The difference in prevalence might be due to this might be due to difference in method used, sample size variation and child feeding practice of the community.
According to this study, Childs age was one of the socio demographic factors associated with stunting in the study area.Children at the age of 6 -11 months were more likely to be stunted than those children in the age of 12-24 months and greater than 24 months.
This study was in agreement with the study conducted in Lalibela town [20], in Hosanna [16] and in Mizan Aman town [15] and not in agreement with the study conducted in Bule hora district,south Ethiopia [22].
This might be due to poor nutritional status of mother's at pregnancy, inappropriate infant and young child feeding practices including breast feeding and complementary feeding and other related factors which were needed to be undergone beginning from conception, through a mother's pregnancy and up until the age of one which was the most critical period in a child's development after child reaches above 24 months of age stunting was irreversible.
Another factor associated with stunting in the study area was age at which complementary feeding started.The result of this study revealed that children who had started complementary feeding at the age of below or above 6 months were more likely to be stunted than those who had started complementary feeding at the age of 6 months.
The association of this dietary factor with stunting was in line with the study done in Meskan district, Gurrage zone, southern Ethiopia [23].
This might be due to inappropriate timing for introducing some kinds of complementary food to a child may affect his/her nutritional status because his/her digestive and immune systems are not yet mature.Introducing supplements before earlier, especially under unhygienic conditions, could be predisposing factor for infection and it leads to malnutrition.
The other factor that was significantly associated with stunting was preceding birth interval of the child Children who had preceding birth interval of less than 24 months were more likely to be stunted than children with preceding birth interval of greater than or equal to 24 months.This result was in line with a study conducted in Mizan Aman town and harerge zone [15,24].This might be due to the child may not be breast feed up to 24 months and a mother may not be feed and give care appropriately due to her second early pregnancy.

Table 2 :
Environmental, health care and child feeding characteristics of children among 5 to 59 months in Shay Bench district , southwestEthiopia , 2016 (n=324)

Table 3 :
A bivariate and multivariate logistic regression output showing factors associated with stunting among 06 to 59 months children, shey bench district, southwest Ethiopia, 2016.