Household Food Insecurity: Associations With At-Risk Infant and Toddler Development

METHODS

RESULTS

In the sample of 2010 families, 21% (n = 427) reported household FI, including 6% (n = 119) that reported FI with hunger. The majority (91%; n = 1486) of the respondents were the birth mother of the child. Compared with children in food-secure households, children in food-insecure households were younger and more likely to have been breastfed and to receive public health insurance (Table 1). Groups did not differ significantly (P ≥ .05) with respect to child's gender, incidence of low birth weight, mean weight-for-age z score, categorical classification as underweight or overweight, or prior hospitalizations. Caregivers who reported household FI were less likely to be <21 years of age, to have been born in the United States, and to be employed. They had less education and were more likely to report depressive symptoms than were caregivers who reported household food security. Food-secure and food-insecure caregivers differed with respect to ethnicity but did not differ with respect to marital status. FI rates did differ according to site of data collection. Regardless of FI status, underweight and overweight were documented at >3 times the number of children expected with weight-for-age values of <5th percentile (∼16%) and >95th percentile (∼20%). Almost 14% (n = 278) of the 2010 caregivers reported developmental risk on the PEDS.

Table 2 shows the proportions of children with developmental risk in unadjusted and covariate-adjusted analyses and the strength of the relationships stratified according to child and caregiver characteristics. With respect to FI group, 18% of children in food-insecure households, compared with 13% of children in food-secure households, were reported to be at developmental risk (P = .007).

The results of multivariate logistic analyses revealed that children from food-insecure households, compared with those from food-secure households, were two thirds more likely to experience developmental risk (adjusted odds ratio: 1.76; 95% confidence interval: 1.26–2.46; P = .001). In multivariate analyses unadjusted and adjusted for other covariates, children were more likely to have developmental risk if they were older, were male, had a low birth weight, were underweight, and had a history of hospital admissions. Children who were underweight, compared with normal weight, were almost 3 times more likely to experience developmental risk. In addition, caregivers who were unemployed or reported depressive symptoms were more likely to report that their children were at developmental risk. There were also geographic site differences in the proportions of children with developmental risk. Caregivers' age and education were not significantly related to developmental risk. The one association that changed with adjustments for covariates was the association between foreign-born caregivers and PEDS results; the unadjusted analysis indicated significance, whereas the relationship of foreign-born caregivers with developmental risk was no longer present after adjustment. When the analysis was repeated after removal of the families that reported FI with hunger, the negative relationship between FI and increased developmental risk was maintained (adjusted odds ratio: 1.77; 95% confidence interval: 1.23–2.56; P = .002).

DISCUSSION

This study identified an association between FI and developmental risk among children <36 months of age from low-income (poor and near-poor) households. Although the detrimental effects of poverty on child development are well documented,²⁸ our study found that the additional association between FI and developmental risk in young children from poor and near-poor households was present even after controlling for theoretically chosen and statistically identified confounding variables. These control variables included child factors, such as previous hospitalizations, low birth weight, and current weight-for-age z score, that usually would be identified by clinicians as markers of physiologic risk.^13,29 The nearly identical relationship between developmental risk and FI that was observed when households that reported FI with hunger were removed from the analysis suggests that the threshold for effects on young children's developmental risk occurs even in households at the less-severe end of the FI continuum. Our findings of greater incidence of developmental risk for very young children from low-income households with limited or uncertain food supplies are consistent with previous findings for school-aged children.^3,4,13,30

There are at least 2 possible pathways that may explain the association between FI and developmental risk. In a nutritive pathway, FI may compel families to limit the quality of food given to their children, leading to micronutrient deficiencies. There is some evidence of an association between FI and iron deficiency,³¹ which has been linked to developmental problems^32–34 and may contribute to the increased rate of developmental risks among children in households with FI. There also may be nonnutritive pathways linking FI and developmental risk. In one possible pathway, families with FI are confronted with the stress and anxiety of not having a steady reliable source of food³⁵ and are at risk for depressive symptoms.^9,36 Caregiver depression has a negative influence on child development,³⁷ particularly in the presence of poverty.³⁸ In the present study, almost one half of the caregivers in food-insecure households reported symptoms of depression, possibly because caregivers in households with FI thought that they could not provide a secure source of food. However, as with other cross-sectional studies that reported associations between FI and maternal depressive symptoms,^9,36 it is not clear whether depression preceded or followed FI.

In another possible nonnutritive pathway, a caregiver report of FI could be a marker for extreme poverty. Caregivers who reported FI had fewer years of formal education, were less likely to be employed, and had children who were more likely to be enrolled in public health insurance programs than did caregivers who reported food security. Although these factors associated with poverty were controlled for in the current analysis, we did not measure whether these extremely low-income households had more-limited access to resources besides food, including toys, books, and other learning materials, and experiences known to be important for promoting child development.^39,40

Our findings must be interpreted in light of several important methodologic issues. First, the study was a sentinel study (conducted in English, Spanish, and Somali) of caregivers and their children 4 to 36 months of age who were waiting for care at 1 of 5 emergency departments and/or clinics that serve large numbers of families from low-income backgrounds. Although the sentinel sample included poor and near-poor caregivers and their children, who were at high baseline risk for negative health and developmental outcomes, the caregivers of the most severely ill and injured children were not included because of their need for immediate medical care. Second, the cross-sectional design can neither establish a causal relationship nor unequivocally ascertain the direction of effect between FI and developmental risk. However, our study results are consistent with recent developmental findings from a longitudinal evaluation of children from kindergarten through third grade.³ Third, although we controlled statistically for important covariate and confounding factors, other unmeasured confounders might have influenced the findings. A less-stimulating home environment related to poverty is probably the most important unmeasured confounder in the relationship between FI and developmental risk. Although we sampled caregivers from poor and near-poor families and adjusted for variables related to poverty, such as type of health insurance and caregiver education and employment, we did not have a measure of family income or the quality of the home environment.

Finally, shared-method variance (ie, the same caregivers reported food security and developmental concerns) could have influenced the results. That is, it is possible that caregivers who were concerned about food access tended to report concerns about child development because they were generally concerned about the overall family situation. However, this threat was minimized because families who expressed concerns but not endorsement of the food security items were not classified as having FI, in keeping with the US Department of Agriculture guidelines.

As expected, cognitive, language, and behavioral concerns are more likely to be identified as the infant develops into toddlerhood, when there are greater expectations of the child and more-complex and more-frequent interactions with the outside world than during the early months. Therefore, although we controlled for the age of the children at the time of examination, caregivers of toddlers were more likely to report that the children were at developmental risk than were caregivers of younger infants. In addition, birth weight, health, and gender are factors that were found in many other studies to influence development, particularly for children living in poverty, depending on the developmental outcome measured.^39–41 Consistent with the work of others, children in this sample who had low birth weights, had been previously hospitalized, and were male were more likely to be at developmental risk than were children who had normal birth weights, had not been hospitalized, and were female. Caregivers who were not born in the United States and caregivers who were employed were less likely to report that their children were at developmental risk than were caregivers in the contrasting groups.

The clinical and public policy implications of this study are striking. Infants who have experienced multiple negative environmental factors are at risk for long-term developmental consequences.⁴² Therefore, the multiple factors for children living in poor and near-poor households who experience household FI and developmental risk could have long-term implications into school age. In contrast, focused interventions in young children have been shown to improve school readiness and long-term outcomes.^30,43–47 Therefore, early identification and remediation of FI, as well as developmental delay, are prudent.

This study of FI and child development highlights the importance of early identification of at-risk children in a model of preventative medicine. The American Academy of Pediatrics recommends that an algorithm be implemented at each well-child visit and states, “early identification of developmental problems should lead to further developmental and medical evaluation, diagnosis, and treatment, including early developmental intervention.”⁴⁸ Evidence suggests that household FI (with or without the report of family hunger), even in the presence of appropriate weight-for-age values, is an important risk factor for the health, development, and behavior of children <3 years of age and, in the future, should be included in algorithms for developmental surveillance.^7,49

Interventions for FI and developmental risk are available and overall have been successful.^44–46,50 Linking families to the Food Stamp Program and/or the Supplemental Nutrition Program for Women, Infants, and Children participation, as well as Early Intervention, Early Head Start, Head Start, and mental health services, is an important intervention that should be recommended if indicated by the risk surveillance or developmental screening. Participation in the Supplemental Nutrition Program for Women, Infants, and Children has been associated with positive infant growth and health.⁵¹ Frongillo et al⁵² reported that starting participation in the Food Stamp Program during the kindergarten to third-grade years was associated with academic (reading and math) improvement, compared with stopping participation in the Food Stamp Program during that same period.

CONCLUSIONS

This study has shown that there is a statistically robust association between household FI and developmental risk during the first 3 years of life, when brain growth is rapid. Given the prevalence of FI in US households with young children, large numbers of children may be at risk of potentially preventable developmental deficits, even if they are not underweight for age. In a time of limited resources, providing nutritional and developmental interventions to young children and their families is a proactive step that might decrease the need for later, more-extensive interventions for developmentally or behaviorally impaired children of school age.⁵³ Future studies should evaluate the longitudinal relationship of FI and infant and toddler development. Those studies should consider direct evaluation of the caregiving environment and child development, as well as other important factors (such as health status, public assistance programs, and caregiver mental health) that may alter the relationship between FI and child development.