Magnitude and determinants of stunting in children under-five years of age in food surplus region of Ethiopia: The case of West Gojam Zone

Background: Child malnutrition is a major public health problem in Ethiopia. Surprisingly, the highest level of stunting is found in food surplus areas of the country. Objective: To identify the determinants of stunting in food surplus areas of West Gojam Zone. Method: A community based cross-sectional survey was conducted on 622 mother-child pairs of 0-59 month old children in Mecha and Wenberma Woredas of West Gojam Zone, Northern Ethiopia between May and June 2006. The study investigated the differential impact of demographic and socio-economic factors, health related factors and dietary factors on stunting among under-five children. Both bivariate analysis and multivariate analysis (logistic regression model) were used to identify the determinants of under-five stunting. Results: The analyses revealed that 43.2 (12.0-17.6) 95% CI percent of the children under age five were suffering from chronic malnutrition, 14.8 (39.3-47.1) 95% CI percent were acutely malnourished and 49.2 (45.3-53.1) 95% CI percent were found to be under-weight. The main contributing factors for under-five stunting were found to be sex of the child, child’s age, diarrhea episode, deprivation of colostrum, duration of breastfeeding, pre-lacteal feeds, type of food, age of introduction of complementary feeding and method of feeding. Conclusion: The findings of this study led to the realization that inappropriate feeding practice is the principal risk factor which brought about nutritional deprivation among under-five children in food surplus areas of Ethiopia. Thus, the importance of appropriate feeding during infancy and childhood cannot be overstated even in food surplus areas. The high prevalence of malnutrition in the study area points out the need to revisit the impression held by many people that malnutrition is not a problem in food surplus areas. Development and implementation of preventive policies aimed at addressing child malnutrition should also consider food surplus areas of the country. [Ethiop. J. Health Dev. 2009;23(2):98-106] Introduction Stunting is one of the most important public health problems in Ethiopia. A national survey undertaken in 1998 among children in the age of 3-5 months showed that the proportion of stunted children was 52 percent (1). The recent Demographic and Health Survey (DHS) of Ethiopia gives a similar picture of the state of stunting to that of the 1998 survey. In this survey, the prevalence of stunting in Ethiopia was 51.2 percent (2). Considering Ethiopia’s position in the rate of stunting, the 1992 national prevalence of stunting (i.e., 64 %) was the highest in the world (3). More surprisingly, a very high prevalence of stunting was observed in food surplus regions of the country. West Gojam Zone is an area with surplus food production, but surprisingly with high prevalence of child malnutrition. According to the 1992 national nutrition survey, the rate of stunting in West Gojam was 75 percent (4). This suggests that food security at regional or zonal level does not necessarily mean nutritional security at individual level. Jemal and Tsegaye, 1999 (5) also indicated that although food security is necessary, it is not the only determining factor in ensuring adequate nutritional status in the area. Zewditu et al, 2001 (6) recommended that the factors contributing to the highest rate of malnutrition need further investigation. The causes of stunting probably vary in different settings, as well as over time. Policy-makers and researchers endlessly debate which of the many causes of malnutrition are most important, and which areas of intervention will be most successful in reducing the problem. Such information is often lacking so unreliable and inadequate decisions are made based on assumptions and unjustified conclusions. This often results in selection of inappropriate policies and programs only to discover the consequences after implementation. Knowledge of the relative contribution of the major risk factors associated with stunting is therefore an important prerequisite for developing nutrition intervention strategies in the area. Despite few local studies conducted in different parts of the country, no previous study attempts to address the shortcomings of the causes of stunting in food surplus regions. The aim of this study is therefore to estimate the level of malnutrition and to identify the determinants of stunting among under-five children in West Gojam Zone for formulation of relevant policy implications and targeted human development policies as well as programs in food surplus areas. Determinants of Stunting in Children 99 Ethiop. J. Health Dev. 2009;23(2) Methods Study area The study was carried out between May and June 2006 in West Gojam Zone, Northern Ethiopia, which is located about 560 km north of the capital, Addis Ababa. In this zone, two woredas, Mecha and Wenberma, were arbitrarily selected. From each woreda, one urban and three rural kebeles were selected randomly for the study. In total, two urban and six rural kebeles were included in the study. Sample size The sample size was calculated by using the formula adopted from Fisher et al (1991) (7) according to the following assumptions: z=1.96, p=0.74, q=1-p and d=0.05. The calculation resulted in a sample of 300 children for a 95% confidence level in each woreda which gives a total sample size of 600 children. Five percent (5%) of the total sample size was added as an attrition rate for any dropout of the study subjects during the study period. Therefore, the actual sample of the study was 630 children. Data collection In each study area, ten enumerators who were able to communicate in Amharic were recruited among candidates who had completed grade 12 and preferably had been involved in other similar field surveys. For effective and quality data collection, a two day intensive training was given to the selected enumerators which covered study objectives, a thorough review of the questionnaire, the use of survey instruments, interview techniques, and direction as to how to administer the structured questionnaire, how to take anthropometric measurements and ethics during field work in line with predesigned training module. Data were collected using a pre-tested structured questionnaire. Mothers or caregivers were personally interviewed. The principal investigator measured and recorded the height and weight of all children selected for the study to uphold consistency of anthropometric measurements. Date of birth of the children, in most cases was established relying on the date given by the mother or care taker. For those with written evidence, date of birth was obtained from clinic cards or child health cards. Data validity and reliability were maintained through close supervision of enumerators by the principal investigator. Anthropometry Height of infants aged 0-23 months was measured in a recumbent position to the nearest 0.1 cm according to the procedure outlined on anthropometric measurement guide using a board with an upright wooden base and a movable headpiece, designed by the Department of Food Science and Nutrition at the Ethiopian Health and Nutrition Research Institute (EHNRI). Height of children 24 months and older was measured in a standing-up position to the nearest 0.1cm according to the procedure described on anthropometric measurement guide using a measuring board designed by EHNRI. Weight of the lightly clothed infants and children was measured to the nearest 10 g by UNICEF Electronic Scale (Item No. 0141015 Scale mother/child, electronic). The UNICEF mother/child electronic scale requires the mother and child to be weighed simultaneously. The mother was weighed with the child and then weighed without the child. The difference between the two measures is the child’s weight. Measurement was taken according to anthropometric measurement guide procedure. Accuracy of all anthropometric measurements was upheld according to the international reference standard. There were no inconsistencies in data or anthropometric measures that could affect the results. Ethical approval The study proposal was presented on the scientific forum of the Ethiopian Health and Nutrition Research Institute and approved at all levels by the Research and Ethical Clearance Committee and director of the institute. The study was also explained to officials of the Zonal administration, Zonal health department of West Gojam Zone and administrative officials of Mecha and Wenberma Woredas. Oral informed consent was obtained from mothers and head of households selected for the study. Statistical analysis Analysis was carried out at two levels. Firstly, a bivariate analysis was performed to determine the differentials of under-five stunting by explanatory variables. Pearson’s chi-square test of independence was performed to test the existence of significant association between stunting and selected risk factors. Secondly, the significant variables (p-value < 0.05) observed in bivariate analysis were subsequently included in multivariate analysis. Logistic regression model was applied to examine independent associations between explanatory variables and a binary dependent variable (stunting). The statistical analysis was carried out using SPSS (SPSS 12.01 for windows SPSS Inc. 2003). Anthropometric indices were calculated using Epi-info software (version 6). The indices are expressed as standard deviation units from the median values of the National Center for Health Statistics (NCHS) standard reference data of US children. Children whose heightfor-age were weight for height and weight for age below minus two standard deviations from the median of the reference population were considered stunted wasted and underweight, respectively. Data processing took place on a private computer not connected to the Internet or any other computer installation. Results Characteristics of the sample A total of 622 children aged 0-59 months enrolled from 2 woredas we