Associations between Stunting and high-ponderosity defined through Weight-for-Height or Body-Mass-Index-for-Age in Under-five Children

Background: Association between overweight and stunting has been inconsistently documented. In under-five children, high-ponderosity is defined as >1SD WHO standards for either weight-for-height or body-mass-index-for-age metrics. Unlike body-mass-index-for-age (BMI-for-age), weight-for-height ignores physiological changes in ponderosity with age, resulting in underestimation of overweight defined through weight-for-height in comparison to BMI-for-age in populations with high stunting prevalence. Consequently, associations between overweight and stunting may differ depending on the metric used. Aim: To test whether concurrent possible risk of overweight-stunting defined through weight-for-height and BMI-for-age (CSPO_WHZ and CSPO_BMIZ) associations are similar. Methods: Demographic Health Survey datasets after 2010 from South-and South-East Asia and Sub-Saharan Africa were evaluated. CSPO_WHZ and CSPO_BMIZ associations were estimated as odds ratio (OR) for individual datasets, which were pooled (random-effects meta-analysis). Stratified analyses were done for age and region. Results: Young-infants (0-6 months) comprised 8%-14% of under-five children, with almost equal representation of boys and girls. Participants, especially Asians, were mostly shorter with lower ponderosity than WHO standards. CSPO_WHZ prevalence was lower than CSPO_BMIZ in 6-59 months, but higher in young infants. Pooled CSPO_WHZ estimates were not significant. In contrast, pooled CSPO_BMIZ associations were significantly positive for, Africa and combined, but not for Asia. Conclusion: CSPO_WHZ and CSPO_BMIZ associations differ, likely because WHZ fails to capture age-related changes in ponderosity.