The results of our study showed that the major risk factors for severe underweight among 6-2-month- old Bangladeshi children hospitalized for the treatment of diarrhoea were related to parental education, employment, and income; child birth-order; and early child-feeding practices. Some of these factors may operate in common to increase the risk of undernutrition. Fathers of 65.5% of the severely-underweight children in our study were rickshaw-pullers or day-labourers with little or no formal education. Not only are these occupations the lowest-paid employment categories in Bangladesh but they also often result in erratic incomes, sometimes yielding in little or no earnings on a particular day. Although it is well-documented that level of parental education is positively associated with the nutritional status of their children (8
), little information is available specifically on the importance of paternal education. Our finding that lower paternal education is a risk factor of severe underweight is in agreement with one other recently-published report (9
) from Bangladesh, which found that education of father was significantly associated with both moderate and severe childhood stunting. Likewise, a study in Uganda found that both economic status and education of father were significantly associated with the nutritional status of children (10
). Results of studies in South India showed that children of fathers who were day-labourers were ~3 times more likely to be severely underweight (11
As with other studies in Bangladesh (9
) and Africa (13
), the present study found that maternal malnutrition was an independent risk factor for severe underweight of children. Undernourished mothers often deliver low-birthweight babies (14
), and their breastfeeding capacity may also be compromised (15
); so, this association is not surprising.
The severely-underweight children in our study were also more likely to have illiterate or less-educated mothers (<5 years of schooling) as has been observed in previous studies in Bangladesh (9
), and the underweight children were three times more likely to have teen-aged mothers than the better-nourished children. A previous report from Kenya also showed young maternal age to be a risk factor for severe PEM (OR=3.95, p<0.001) (23
). Illiterate or less-educated and younger mothers usually have less knowledge of appropriate childrearing practices and optimal environmental and personal hygiene, and they generally have less status in the family (24
), thereby rendering them less capable of providing adequate childcare and accessing formal health services.
Several previous studies examined the relationship between child birth-order and risk of malnutrition, although the results are inconsistent. One recently-published report from Bangladesh found a greater risk of stunting among higher birth-order children (9
), and a study in South Africa found higher birth-order (>3) as a risk factor (OR=2.3, 95% CI 1.5-5.1) for all forms of severe PEM (marasmus, marasmic kwashiorkor, and kwashiorkor) (26
). On the other hand, a study in Egypt did not find any relationship between birth-order and undernutrition (27
Our finding of inadequate/improper breastfeeding as a risk factor corroborates the findings of several other studies in Bangladesh, which reported that inadequate breastfeeding, early supplementation of infant formula or cow's milk, and early introduction of semi-solid complementary foods were important risk factors for malnutrition (9
). The hygienic and nutritional risks associated with bottle-feeding and artificial milks are well-known (29
), and previous studies also found that breastfeeding had a significant and substantial impact on overall survival of undernourished children (32
). It is also conceivable that the association with a shorter duration of predominant breastfeeding could be an example of reverse causality, whereby children who were ill and malnourished stopped nursing or were provided with other foods. Severely-malnourished children are more likely to have young mothers and to have been born prematurely or with a low birth- weight. Small, premature or malnourished infants tend to breastfeed less often and have a less vigorous suck (34
). This produces less prolactin release and less production of breastmilk. Young mothers and mothers with low educational level may have less problem-solving skills, leading to an inability to support their infants when food supplies are limited, which, in turn, leads to malnutrition. The cross-sectional design of the present study does not allow us to distinguish between these possibilities.
Factors associated with severe underweight: results of logistic regression model
The risk factors identified for severe underweight can be used, both to design and target preventive interventions. Several factors, such as those relating to infant-feeding practices and birth-order, are potentially modifiable; so, these can be used for designing intervention programmes. For examples, interventions can be developed to motivate behaviours that are more consistent with recommended feeding practices or to promote adoption of family-planning measures.
The causes of severe underweight are complex and involve the multiple dietary, environmental and other underlying socioeconomic factors, and carefully conceived, broad-based preventive programmes will be necessary to ameliorate the current situation.