Background: Undernutrition in early life (UELife) is a condition associated with greater occurrence of chronic diseases in adulthood. Some studies on this relationship have used short stature as indicator of UELife. However, other non-nutritional factors can also determine short stature. Depending on the severity of UELife, the human body reacts primarily compromising weight and length gain, but prioritizing brain growth, resulting in disproportionate individuals. Based on this premise, this study aimed to validate a new anthropometric indicator of UELife.
Design: Using stature and head circumference data from a probabilistic sample of 3,109 women, the Head-to-Height Index was calculated: HHI = (head × 2.898)/height. A HHI >1.028 (75th percentile) was the best cutoff for predicting obesity (best balance between sensitivity/ specificity, largest area under the receiver operating characteristic curve, and highest correlation coefficient) and was used to define the condition of body disproportionality. The strength of associations with several outcomes was tested for both disproportionality and short stature (height ≤25th percentile: 153.1 cm).
Results: In adjusted analysis for confounding factors (age, smoking, and education level), the strength of the associations between body disproportionality and the analyzed outcomes was greater than that observed when short stature was used. Respectively, the observed prevalence ratios (95% CI) were (P<0.05 for all comparisons): obesity: 2.61 (2.17-3.15) vs 1.09 (0.92-1.28); abdominal obesity: 2.11 (1.86-2.40) vs 1.42 (1.27- 1.59); high blood pressure: 1.24 (1.02-1.50) vs 0.90 (0.75-1.08); hypercholesterolemia: 2.98 (1.47-6.05) vs 1.65 (0.91-2.99); and hypertriglyceridemia: 1.47 (1.07-2.03) vs 0.91 (0.69-1.21).
Conclusion: Body disproportionality is a more accurate indicator of UELife than short stature. While short stature may be genetically determined, a high HHI is due to metabolic adaptations to undernutrition in early life.
Keywords: anthropometric indices; cardiovascular risk; dyslipidemia; epidemiological survey; metabolic risk factors; obesity.