Índice perímetro cefálico-para-estatura: proposição de um novo Indicador de desnutrição no inicio da vida e sua associação com a obesidade e fatores de risco metabólico

Abstract

Undernutrition in early life (UELife) has been a condition associated with greater occurrence of chronic diseases in adulthood. In adults, this condition has been identified by stature deficit. However, other non-nutritional factors may also determine short stature. Depending on the insult, the human body compromises weight gain and length, preserving brain growth, resulting in disproportionate individuals. In this context, the present work aimed to characterize the Head-to-Height Index (HHI) as a predictor for UELife and its relationship with obesity and metabolic syndrome in the adult phase of life in women, as well as to identify possible confounding factors associated with its occurrence. For this, besides the literature review, two articles were elaborated. The first aimed to validate a new anthropometric indicator for UELife. From the height and cephalic perimeter of a probabilistic sample of 3,109 women, the head-height index was calculated: HHI = (head x 2,898) / height. HHI> 1.028 (75th percentile) was the best cutoff point for predicting obesity (better balance between sensitivity / specificity, higher area under the ROC curve and higher correlation coefficient) and was used to define the condition of body disproportion. The strength of associations with several outcomes was tested for both isproportionality and short stature (height ≤25th percentile: 153.1cm).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). Therefore, body disproportion can be considered as a more accurate indicator of UELife than short stature. While short stature may be genetically determined, a high HHI may be due to metabolic adaptations to undernutrition in early life. The second article aimed to identify the prevalence and factors associated with the occurrence of elevated HHI and its association with metabolic outcomes in women from a Brazilian Northeastern state. It was also a cross - sectional study, with a probabilistic sample representative of women aged 20 to 49 years of age of Alagoas. The high head-to-height disproportion was defined by ICE> 1.028. A total of 3,109 women were studied, of which 56.3% belonged to the lower economic classes (D and E). The prevalence of elevated ICE was 25%, a condition that was independently associated to the following variables: economic classes C (RP = 1.33; 95% CI: 1.02-1.76) and D + E (RP = 1.56; 95% CI: 1.20-2.03), age ranges from 30 to 39 (RP = 1.35; 95% CI: 1.14-1.60) and from 40-49 years (RP = 1.73; 95% CI 1.47-2.04), and age of menarche less than 12 years (RP = 1.23; 95% CI: 1.07-1.41). All the indicators of greater body fatness were associated with high ICE: obesity (PR = 1.73; 95% CI: 1.55-1.94), body fat% ≥ 33 (PR = 1.35; 95% CI: 1 , 26-1,46), waist circumference> 80 cm (RP = 1.16; 95% CI: 1.09-1.22) and metabolic syndrome (OR = 1.19, 95% CI 1.03-1 , 40). High ICE was associated with the highest age group, lower economic class, menarche age less than 12 years, obesity, waist circumference> 80 cm and metabolic syndrome. These results show that high ICE can be considered a marker of metabolic adaptations imposed by malnutrition experienced in early life.