Early childhood undernutrition, preadolescent physical growth, and cognitive achievement in India: A population-based cohort study

Author summary Why was this study done? India has the largest number of undernourished children under the age of 5.

Previous studies report an absence of gender disparities among child undernutrition in India despite well-documented disparities in adulthood.

Current national programs for addressing child undernutrition focus on the first 5 years of life and do not include gender-focused interventions.

What did the researchers do and find? We carried out a population-based cohort study based on data gathered prospectively from nationally representative survey of 41,554 households in India in 2004 to 2005 and a follow-up in 2011 to 2012 among 83% of the same households.

This study leverages India's only nationally representative panel dataset to report that undernutrition in the first 5 years of life is associated with increased odds of adverse physical outcomes, i.e., having short stature and being very thin and cognitive outcomes, i.e., unable to read and do arithmetic during preadolescent years.

Female children who were undernourished were the most vulnerable for experiencing these adverse outcomes, and the gender disparities widened with age during the preadolescent period. As an example, the adjusted probability of short stature for undernourished female children increased from 31% among 8 year olds to 45% among 11 year olds. There was no such increase observed among male children.

Presence of a woman in the household with more than secondary level of education mitigated the disadvantage associated with both being undernourished and being a female child.

What do these findings mean? Sex differences in physical and cognitive outcomes emerge during preadolescent period and are associated with early childhood nutrition.

Higher level of female education within the household is an important protective factor for these disparities.

Elevation of women's status through improved female education should be central to the national level programs in India focused on maternal and child health.

Background There is a lack of nationally representative estimates for the consequences of early child undernutrition on preadolescent outcomes in India. Understanding this relationship is helpful to develop interventions that not only prevent child undernutrition but also mitigate its consequences.

Methods and findings In this cohort study, we analyzed prospectively gathered data from 2 waves of the India Human Development Survey (IHDS) to investigate the association of undernutrition during early childhood (0 to 5 years) in 2004 to 2005 with physical and cognitive outcomes during preadolescent (8 to 11 years) years in 2011 to 2012. These surveys interviewed 41,554 households across all 33 states and union territories in India in 2004 to 2005 and reinterviewed 83% of the households in 2011 to 2012. Primary exposure was assessed using the Composite Index of Anthropometric Failure (CIAF) based on 2004 to 2005 survey. Primary outcomes were short stature (height-for-age z-score [HAZ] <-2), thinness (body mass index [BMI] <18.5 kg/m(2)), reading, and arithmetic skills during preadolescence based on the 2011 to 2012 survey. Survey-weighted generalized linear models were used, and effect modification based on child sex and sociodemographic variables were evaluated using 3-way interaction terms. Of the 7,868 children included in this analysis, 4,334 (57.3%) were undernourished. Being undernourished was associated with increased odds of short stature (odds ratio [OR] 1.73, 95% confidence interval [CI] 1.45 to 2.06) and thinness (OR 1.52, 95% CI 1.33 to 1.73) during the preadolescent period, while it was associated with decreased odds of achieving a higher reading (cumulative odds ratio [cumOR]: 0.76, 0.66 to 0.87) and arithmetic (cumOR: 0.72, 0.63 to 0.82) outcomes. The disparity in outcomes based on CIAF increased with age, especially for girls. Increased level of female education within the household reduced the disadvantages of undernutrition among female children. Study limitations include observational and missing data, which limit our ability to draw strong causal inferences.

Conclusions In this study, we found that early child undernutrition was associated with several adverse preadolescent physical and cognitive outcomes, especially among female children. Improved female education mitigates this association. Female education promotion should assume a central role in Indian public health policy making.