Trunk‐to‐leg ratio in regions of extreme stunting prevalence in the Western Highlands of Guatemala: A comparative perspective and interpretation

Background CeSSIAM has an interest in the origins and biology of acquired linear growth retardation, also referred to as “stunting” or “chronic undernutrition.” Towards overcoming the tactile disadvantage of direct measuring tape assessment and the gluteal‐thickness artifact in sitting height, we developed a photographic approach to estimating differential body segment lengths: trunk vs leg. Current experience suggests photographic imaging to be easily reproducible, less invasive and more objective than the aforementioned techniques. Preliminary studies defined body segment lengths in normal‐height and modestly‐stunted Guatemalan preschoolers. Objective To document any further effects on the body‐segment ratios that might occur with the even more profound stunting occuring in the far western highlands of Guatemala. Methods The height and clothing‐adjusted weight of 212 individuals between 4 – 7 y from zones of established high stunting prevalence (combining La Estancia and Santa María Chiquimula {Com}) were measured. Two, partly‐overlapping samples of 102 children each were pair‐matched by age and sex to a previous series of equal numbers of affluent (Quetzaltenango City {Que}) and of poor urban children (Sololá {Sol}). The former sample was derived from matching by sequential enrollment (Com1) and the latter was enriched for stunting using the shortest children available for matching (Com2). A sagittal photograph was taken with a digital camera with the child in an erect posture with the Frankfort gaze standing on a stadiometer platform. After printing out the photo, the lengths of the trunk and the legs were measured in mm, allowing the generation of trunk‐to‐leg ratios. Results The stunting prevalence for the four respective series increased progressively: 5.9% (Que); 46.1% (Sol); 68.6% (Com1); and 87.3% (Com2). Children in the Com1 sample were 9.2% shorter on average than those in Que and 3.4% shorter than Sol. Those in the Com2 sample were 10.9% and 5.0% shorter, respectively. The median trunk‐to‐leg ratios across the four respective series were 0.76; 0.82; 0.81; and 0.82. This value declined to 0.85 for third degree stunting alone (n=52). Conclusion As stunting prevalence increases in a population, the median trunk‐to‐leg ratio initially falls to the 0.82 range and stabilizes thereafter, but in isolated third‐degree stunting, the median trunk‐to‐leg ratio reaches 0.85.