Factors associated with stunting among children of age 24 to 59 months in Meskan district, Gurage Zone, South Ethiopia: a case-control study

Adequate provision of nutrients is crucial to ensure good physical & mental development as well as for long-term health. Undernutrition accounts 35% of all deaths among under-five children. More than 2 million under-five children die each year due to undernutrition [1]. Undernutrition refers to a state resulting from a relative or absolute deficiency of one or more essential nutrients. The three main indicators used to define undernutrition, i.e., stunting, underweight and wasting; that represent different histories of nutritional insult to the child and measured by height for age, weight for height and weight for age indexes respectively. Stunting is a measure of chronic malnutrition. Undernutrition in low and middle-income countries was high. Both stunting & underweight are highest in Eastern Africa. About 42% of children in sub-Saharan Africa and 182 million (32.5%) children in developing countries were undernourished and the stunting trend was stagnant in Africa from1990 to 2010 [2‐6].

Undernutrition can best be described in Ethiopia as a long term year round phenomenon due to chronic inadequacies of food combined with high levels of illness in under-five children which 44.0%, 29.0% & 10.0% were stunted; underweight and wasted respectively [7]. Similarly 53.6%, 32.7% & 7.0% of children aged 24 to 59 months were stunted, underweight and wasted respectively [7].

Studies show that stunting is associated with deprived attention, memory impairment, reduced learning, and memory in children, low school enrollment, and decreased higher cognitive functioning with a slowing in the rate of cognitive development. These finally result in low adult wages and lost productivity [8‐10].

The causes of malnutrition are numerous and multifaceted. These causes are intertwined with each other and are hierarchically related. The most immediate determinants are poor diet and disease which are themselves caused by a set of underlying factors; household food security, maternal/child caring practices and access to health services and healthy environment. These underlying factors themselves are influenced by the basic factors (socio-economic and political conditions) [2, 11].

Undernutrition are multiple and inextricably linked to poverty (low socioeconomic status). Many studies revealed that lowest prevalence of stunting was found among children from families with higher per capital income (socioeconomic status) [12‐14]. When a child lives in an area of low income level the chance of disease increase and these diseases can increase the risk of stunting [15]. More children suffering from stunting were observed among mothers of low educational levels than those with high educational levels [13, 16, 17]. Under- five children living in a household with large family were at higher risk of being stunted. Similarly, under- five children living in households with more than one under-five were more likely to be stunted [12, 13, 17]. Studies conducted in Ethiopia and abroad reported that the quantity, frequency, and type of supplementary feeding, birth weight, sex, birth order and disease conditions like diarrhea were strongly associated with stunting among under-five children [13, 15, 18‐30]. Housing environment such as lack of safe water supply, access to a toilet facility and inadequate sanitation were among the factors that increased the risk of stunting [20, 25].

Comprehensive knowledge about the risk factors of stunting in local context is vital to reduce stunting rate, to develop prevention strategies and strengthen nutrition intervention programs. Despite higher prevalence of stunting among children age 24 to 59 months, there are limited studies that reports about risk factors of stunting among children age 24 to 59 months separately. Besides neither case-control nor cohort study was done to identify risk factors of stunting in the district. Thus the purpose of this study was to assess factors associated with stunting among children of age 24 to 59 months in Meskan district for the development and improvement of implementation and intervention strategies to reduce child mortality and morbidity.

A total of 242 children (121cases and 121 controls) were participated in this study. All of the study participants were singleton birth. Sixty five (53.7%) of cases as well as controls were male. The median birth orders of cases & controls were 4 and 3 respectively. Hundred thirteen (93.4%) of children’s mothers were Gurage by their ethnicity. Majority of participants’ mothers, 97(80.2%) of cases and 90(74.3%) of controls, were Muslim by religion. Mothers of 68(56.2%) and 59(48.8%) of cases and controls were illiterate respectively. Nearly two fifth of the controls’ mothers were house wife (Table 1).

Study participants (children) living in households with eight to ten [Adjusted Odds Ratio (AOR) = 4.44, 95% CI: 1.65, 11.95] and five to seven [AOR = 2.97, 95% CI: 1.41, 6.29] family members were more likely to be stunted than those living in households with two to four family members. Similarly, children living in households with three under-five children [AOR = 3.77, 95% CI: 1.33, 10.74] were more likely to develop stunting than those living in households with one under-five child. Children whose mothers worked as merchants [AOR = 4.03, 95% CI: 1.60, 10.17] and farmers [AOR = 3.92, 95% CI: 1.89, 8.16] were more likely to be stunted than children whose mothers worked as house wives. Children who breast fed for less than two years [AOR = 5.61, 95% CI: 1.49, 11.08] were more likely to be stunted than those who breast fed for two or more years. Children who were exclusively breast fed for less than six months [AOR = 3.27, 95% CI: 1.21, 8.82] and greater than six months [AOR = 7.62, 95% CI: 1.80, 12.23] were more likely to develop stunting than children who were exclusively breast fed for the first 6 months. Children who bottle fed [AOR =3.30, 95% CI: 1.33, 8.17)] and fed by hand [AOR = 3.04, 95% CI: 1.46, 6.32] were more likely to be stunted than children who fed their complementary food using spoon/cup (Table 2).

This study intended to identify the factors associated to stunting among children age of 24 to 59 months using analytic study design. However, certain limitations may arise in the study such as recall bias and absence of data on: maternal nutrition, heights of the mothers, household food security and parasitic infections. There may be also misclassification of case and control, because of it is very difficult to get accurate age in country like Ethiopia. Efforts were made to get accurate age by asking for immunization card of the participants during the census. Lastly, since case-control study design was employed, it does not enable to establish temporality.

In this study participants living in households with high number of under-five children were about 4 times more likely to develop stunting than those living in households with least number of under-five children. This is consistent with community based studies conducted in southern Brazil and South Africa [12, 17]. Similarly children living in households with eight to ten family members were 4.44 and living in household with five to seven family members were 2.97 times more likely to develop stunting compared with those living in household with two to four family members. This might be due to resource depletion which exposed to poverty and decrement in food availability and also suggesting that there is more competition for available food when the household is large. This is in line with studies conducted in Northeastern Brazil, South Africa and Ethiopia [13, 17, 18]. But which is inconsistent with study conducted in Uganda [30].

Children whose mothers worked as merchant and farmer were more likely to develop stunting than children whose mothers worked as house wives. This might be due to decreased contact time to the child that brings short period of exclusive breast feeding, early cessation of breast feeding, increase exposure to bottle feeding and improper complementary food, which may have a large negative effect on the growth children. Our results are not consistent with studies that had shown a protective effect of maternal employment by increasing income and female autonomy. Employment may also positively influence food security, quality of diet and use of health services [21]. The difference is probably due to the fact that factors like child caring practice were overlooked in the previous study.

The likelihood of stunting was` higher among children who exclusively breast fed below or above the age of six months compared with who exclusively breast fed for six months. This finding was in line with study conducted different areas [17, 20, 23]. 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 an important cause of malnutrition. On the other hand some studies demonstrated that association was not observed [22, 30]. The difference is probably due to difference in study design as well as geographical difference.

Our study showed that feeding complementary food using bottle and by hand increases the risk of stunting among children. This finding is consistent with other studies conducted in our country [23] in which feeding using bottle and hand were associated with increase the odds stunting.

This study showed number of under-five children, family members, maternal occupation, duration of breast feeding, duration of exclusive breast feeding & method of feeding complementary food were independently associated with stunting. Thus, national public health intervention programmer and stakeholder working on improving child nutrition should focus on these determinants to reduce stunting. Health extension workers shall educate mothers/caretakers on the importance of exclusive breast feeding, methods of complementary feeding and adequate spacing between children. Program planner and policy makers should consider & strengthen collaboration and coordination of nutritional program that aimed to alleviate nutritional deficiencies and family health program.