Vitamin D Levels and Cardiometabolic Markers in Indigenous Argentinean Children Living at Different Altitudes.

The objective of this study was to assess the association between vitamin D and cardiometabolic markers in 2 indigenous communities from similar ethnic backgrounds, but living at different altitudes. A cross-sectional study compared 152 (72 females) indigenous schoolchildren from San Antonio de los Cobres (SAC), 3750 m above sea level, with 175 (86 females) from Chicoana (CH), 1400 m above sea level, mean age 9 years. Anthropometry, blood pressure, lipids, glucose, insulin, and vitamin D were assessed in spring season. The prevalence of children's overweight/obesity was significantly lower in SAC, 9.2% (13), than in CH, 41.5% (71). There was a significantly higher prevalence of vitamin D deficiency (<20 ng/mL) in SAC (n = 103, 67.7%) than in CH (n = 62, 36.3%). SAC showed an inverse correlation between vitamin D and insulinemia (r = -0.17, P < .05), whereas CH showed an inverse correlation between vitamin D and systolic blood pressure (r = -0.19, P < .05), z-BMI (body mass index; r = -0.25, P < .01), triglycerides (r = -0.15, P < .05), glucose (r = -0.35, P < .05), and insulinemia (r = -0.24, P < .01). Multiple linear regression analysis showed that vitamin D (ß = -.47; R 2 = .21) was significantly associated with SAC location, adjusted for confounding variables. Vitamin D levels were significantly and directly associated with altitude and inversely with metabolic markers, suggesting that populations living at high altitudes are at higher risk for future cardiovascular diseases.

Blood pressure levels among Indigenous children living at different altitudes.

The objective was to compare blood pressure (BP) levels in 2 groups of Indigenous Argentine school children from similar ethnic backgrounds but living at different altitudes. One hundred and fifty-two (46.3%) children (age, 4-14 years) from San Antonio de los Cobres (SAC), at 3750 m above sea level, and 176 children (53.7%) from Chicoana (CH), at 1400 m above sea level, participated in this cross-sectional study. Data for children's anthropometry, BP, glucose, lipids, vitamin D, and insulin, as well as mothers' height and weight were assessed. Hypertension was defined as BP ≥ 95th percentile. The prevalence of overweight/obesity among children was significantly lower in SAC (n = 17, 11.2%) than in CH (n = 74, 42%) (body mass index (BMI) > 85th percentile per US Centers for Disease Control and Prevention norms). However, the prevalence of hypertension was significantly higher among children in SAC (n = 15, 9.9%) than among those in CH (n = 2, 1.1%). Children were divided into 4 groups by mean arterial BP quartiles for comparison by ANOVA. As mean arterial BP increased, age, BMI, glucose, triglycerides, triglycerides/high-density lipoprotein cholesterol, and insulin levels increased significantly. Multiple linear regression analyses showed that children's mean arterial BP was significantly associated with altitude adjusted for confounding variables (R2 = 0.42). Furthermore, when mean arterial BP was replaced by systolic BP (R2 = 0.51) or diastolic BP (R2 = 0.33), similar results were obtained. Our results suggest that Indigenous children who live permanently at high altitude have higher levels of BP, adjusted for confounding variables. Routine BP measurements conducted in the SAC community could be essential for the prevention of cardiovascular disease.

Type 2 diabetes markers in indigenous Argentinean children living at different altitudes.

BACKGROUND: Exposure to hypoxia at high altitude is increasingly being recognized as a risk factor for metabolic diseases. OBJECTIVE: To determine the association between Type 2 diabetes (T2D) risk factors and altitude in two groups of Argentinean indigenous schoolchildren who live permanently at different altitudes. METHODS: This cross-sectional study compared 142 schoolchildren from San Antonio de los Cobres (SAC), 3750 m above sea level, with 171 from Chicoana (CH), 1400 m. Data for children's anthropometry, blood pressure and lipids, as well as mothers' height and weight were assessed. RESULTS: There was not a significant difference in age between SAC (9.0 + 2y) and CH (9.4 + 2y) children. However, mean children's weight (29 vs. 38 kg), height (130 vs. 138 cm), BMI (17 vs. 19 kg/m2), and HDL-C (46 vs. 48 mg/dL) were significantly lower in SAC than in CH, respectively. In contrast, systolic blood pressure (87 vs. 70 mmHg), cholesterol (157 vs. 148 mg/dL), and triglycerides (104 vs. 88 mg/dL) were significantly higher in SAC than in CH, respectively. There was not a significant difference in age (33.2 + 7y vs. 34.4 + 8y) and BMI (26.2 + 4y vs. 28 + 5y) between SAC and CH mothers. Multiple linear regression analyses showed that children's blood pressure (R2 = 0.38), triglycerides (R2 = 0.21), and HDL-C (R2 = 0.16) were significantly associated with altitude, adjusted for confounding variables. CONCLUSION: This study shows that indigenous Argentinean children living at 3750 meters have higher T2D risk compared with those living at 1400 meters above sea level.