Double burden of malnutrition by mid-childhood in an Indian birth cohort: a longitudinal study (2010-2021).

Background: The double burden of malnutrition (DBM) is characterized by concurrent malnourishment and obesity and is largely prevalent in low- and middle-income countries. This study evaluated the longitudinal patterns of body mass index (BMI) from birth to 9 years of age in an urban Indian birth-cohort: Malnutrition and Enteric Disease (MAL-ED) cohort, to understand the emergence of DBM and the role of early-life factors. Methods: The MAL-ED study recruited 251 children from urban slums in Vellore, Tamil Nadu, India, between 2010 and 2012, with further follow-ups conducted until 9 years of age. Standardized anthropometric measurements were performed at the ages of 2, 3, 4, 5, 7, and 9 years, with additional BMI calculations performed at each time point. After normality checks, appropriate statistical analyses were performed for individual variables, and later-life BMI was modeled using multinomial regression. Findings: Approximately 45% of children were stunted at 2 years of age. By 7 years, 26.3% of children were classified as thin with 5.2% of children classified as overweight/obese. By 9 years, the prevalence of underweight was 21.6%, while overweight/obesity increased to 14.6%. Maternal BMI was a predictor of childhood thinness, particularly at ages 5 and 9. Interpretation: DBM though present in early childhood, became more pronounced after 5 years of age and intensified by 9 years. Low maternal BMI was associated with the BMI trajectory of the offspring. Hence, age-specific and maternal health interventions are crucial for addressing the risk of DBM in vulnerable children. Funding: This research was supported by the Bill and Melinda Gates Foundation (grant no. OPP 47075) for the original MAL-ED study, DBT/Wellcome Trust India Alliance fellowship (grant no. IA/CPHI/19/1/504611) for the follow-up and TIFR-DAE funding (RTI4003; 19P-0911).