Child undernutrition in one of the cities with greater nutritional risk in Brazil: population-based study in the Western Brazilian Amazon.

Objective: To estimate the prevalence of child undernutrition and associated factors in a municipality with high nutritional risk in Brazil. Methods: This cross-sectional, population-based study was conducted with a sample of 478 children aged under 5 years in the city of Jordão, Acre, Brazil. The following indicators were calculated: weight for age (W/A), height for age (H/A), and weight for height (W/H), using the growth curves of the WHO as reference, which adopts a cutoff of -2 z scores for identification of malnourished children. Adjusted prevalence ratios (PRs) were obtained using multiple Poisson regression models with robust error estimate (p < 0.05). Results: A high prevalence of stunting (35.8%) was observed. Children with indigenous ancestry living in rural areas showed the highest prevalence of malnutrition (59.4%). After controlling for age, gender, and indigenous ancestry, the factors associated with stunting risk were: living in rural area (PR = 1.6; 95%CI 1.2 - 2.1); lower tertile of household wealth index (PR = 1.6; 95%CI 1.1 - 2.3); living in houses made of walking palm (PR = 1.6; 95%CI 1.1 - 2.4); maternal height less than or equal to 146.4 cm (PR = 3.1; 95%CI 1.9 - 5.0); and history of introduction of cow's milk before 30 days of age (PR = 1.4; 95%CI 1.0 - 1.8). Children with updated vaccination cards were inversely associated with stunting risk (PR = 0.7; 95%CI 0.5 - 0.9). Conclusion: Child undernutrition remains a serious public health problem in the Amazon, indicating additional difficulties in facing the problem in this region of the country.