Fourteen-year trends in overweight, general obesity, and abdominal obesity in Amazonian indigenous peoples.

BACKGROUND: Available data show that the epidemiological profile of most indigenous Brazilian populations is characterized by the coexistence of long-standing health problems (high prevalence of infectious and parasitic diseases, malnutrition, and deficiency diseases, such as anemia in children and women of reproductive age), associated with new health problems, especially those related to obesity (hypertension, type 2 diabetes mellitus and dyslipidemia). Based on this scenario, this study analyzed the nutritional profile of the adult population of seven indigenous peoples from the Brazilian Amazon in the years 2007 and 2021. METHODS: A total of 598 adults individuals were analyzed in 2007 (319 women and 279 men) and 924 in 2021 (483 women and 441 men), from seven indigenous peoples located in the state of Pará, who were assisted during health actions carried out in 2007 and in 2021. Body mass index classification used the World Health Organization criteria for adults: low weight, < 18.5 kg/m2; normal weight, ≥ 18.5 and < 25 kg/m2); overweight, ≥ 25 and < 30 kg/m2, and obesity, ≥ 30 kg/m2. A waist circumference (WC) < 90 cm in men and < 80 cm in women was considered normal. RESULTS: The data revealed heterogeneous anthropometric profiles, with a low prevalence of nutritional changes in the Araweté, Arara and Parakanã peoples, and high proportions of excess weight and abdominal obesity in the Kararaô, Xikrin do Bacajá, Asurini do Xingu and Gavião peoples, similar to or even higher than the national averages. CONCLUSION: Different stages of nutritional transition were identified in the indigenous peoples analyzed, despite apparently having been subjected to the same environmental pressures that shaped their nutritional profile in recent decades, which may indicate different genetic susceptibilities to nutritional changes. The evidence shown in this study strongly suggests the need to investigate in greater depth the genetic and environmental factors associated with the nutritional profile of Brazilian indigenous peoples, with assessment of diet, physical activity and sociodemographic and socioeconomic variables that enable the development of appropriate prevention and monitoring measures.

High prevalence of anti-SARS-CoV-2 IgG antibody in the Xikrin of Bacajá (Kayapó) indigenous population in the brazilian Amazon.

The COVID-19 pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) reached the Brazilian Amazon and spread among indigenous populations. In the present study, we demonstrate a high prevalence of infection among the Xikrin of Bacajá people (Kayapó). A sample of 100 individuals of both sexes (51 men and 49 women) with ages ranging from 2 to 82 years were clinically evaluated and tested for the presence of anti-SARS-CoV-2 IgG antibody. Among all investigated individuals, 58 were IgG-reactive (58 %) by a rapid test, and 73 (73 %) were reactive in an enzyme-linked immunosorbent assay, with no difference between sexes. Oxygen saturation ranged from 82 to 99 %, with the lowest value observed in a two-year-old girl. The results show that as expected, SARS-CoV-2 infection rapidly reached more than 70 % of the population, most likely because of the difficulties of maintaining social distance due to cultural characteristics. These results highlight the importance of indigenous health policies as a means of minimizing the impact of the pandemic on these communities.

Postpartum amenorrhea duration by sex of the newborn in two natural fertility populations.

OBJECTIVES: Postpartum amenorrhea (PA) affects the length of interbirth intervals and thus is intimately related to human life history strategies. PA duration appears to be influenced by maternal energetic status. In humans, as in other mammals, sons are costlier than daughters. Thus, we hypothesize that, in energetically constrained environments, a newborn's sex should be associated with PA duration. METHODS: We analyzed data from two natural fertility populations in which mothers have differing energy budgets: Qom women (n = 121) from a periurban village in Argentina, who have a comparatively calorically dense diet and are sedentary (prepregnancy mean BMI = 24.8 ± 4.5 kg/m2 in 1997), and agropastoral Kaqchikel Maya women (n = 88), who have a comparatively calorically restricted diet and high physical activity levels (mean BMI = 21.8 ± 3.7 kg/m2 ). We predict that (a) mothers of sons exhibit longer PA duration than mothers of daughters and (b) this association between offspring sex and PA duration is stronger in the Maya, who have smaller energy budgets. RESULTS: Maya mothers with sons exhibited estimated mean and median PA durations that were 1.34 times the estimated mean and median PA duration of mothers with daughters (p = 0.02). Among the Qom, mean, and median PA duration did not differ significantly in relation to offspring sex (p = 0.94). CONCLUSIONS: Maya mothers with sons exhibited longer PA duration than those with daughters. This phenomenon was not observed in the well-nourished Qom, possibly due to "buffering" effects from larger energy budgets. Offspring sex may influence birth spacing and maternal life history strategies in energetically constrained environments.

Newborn anthropometry, maternal capital, and altitude in the highland population from the province of Jujuy, Argentina.

OBJECTIVE: To analyze variability in newborn (NB) anthropometry among Jujenean NBs as a function of geographic altitude (500 m to ≈4000 masl), maternal anthropometry and other maternal characteristics within the maternal capital framework. MATERIALS AND METHODS: Data obtained from 41,371 mother/child pairs recorded in the Jujuy Perinatal Information System (SIP) between 2009 and 2014, including: NB and maternal weight, length/height and BMI; gestational age (corrected); maternal age, educational level, nutritional status, and marital status; birth interval; and planned pregnancy. Based on the declared place of residence, the prevalence of unsatisfied basic needs (% UBN) was determined and the data was split into two altitudinal groups: highlands (HL, >2500 masl) and lowlands (LL, <2500 masl). ANOVA, Chi-squared and Pearson tests were applied as needed. Statistical associations between the response variables-NB weight, length and BMI-and maternal and environmental variables were tested using a Generalized Additive Mixed Model (GAMM). RESULTS: All NB and maternal anthropometric variables were lower in HL compared to LL; they also presented negative correlations with altitude, except NB length. Apart from gestational age and birth interval, HL and LL presented statistically significant differences in all study variables. GAMM results showed that maternal anthropometry was the main influence on NB weight and length. DISCUSSION: Of all the maternal capital features examined, only maternal anthropometric variables were found to protect offspring against the negative impact of HL environments.

Revelations of ancient head shape: Cranial modification in the Cuzco region of Peru, Early Horizon to Inca Imperial Period.

OBJECTIVES: Cranial vault modification (CVM), the intentional reshaping of the head, indicated group affiliation in prehistoric Andean South America. This study aims to analyze CVM data from the Cuzco region of Peru to illuminate patterns of early migration and settlement along with the later impact of the Inca Empire (AD 1438-1532) on the ethnic landscape. MATERIALS AND METHODS: 419 individuals from 10 archaeological sites spanning over 2300 years were assessed for CVM using morphological analysis. RESULTS: CVM patterns show distinct temporal attributes: the tabular type of modification appeared first and dominated the early sample (900 BC-AD 600), followed by an influx of unmodified crania during the Middle Horizon (AD 600-1000). The annular type appeared later during the Late Intermediate Period (AD 1000-1438). In the subsequent period of Inca imperialism, modification rates were higher at sites in the Cuzco countryside than in Cuzco city sites. DISCUSSION: The study results, combined with archaeological and ethnohistoric data, reveal the sociopolitical transformations that occurred prior to and during the rise of the Inca Empire. The influx of unmodified crania during the Middle Horizon resulted at least partly from Wari occupation, while the appearance of the annular type during the LIP points to migration into the area, possibly from the Lake Titicaca region. In the Inca Imperial Period, Inca individuals at Cuzco city sites refrained from modification as a sign of their ethnic identity, while modification patterns in the Cuzco countryside likely reflect state-coerced resettlement of different ethnic groups.

Metabolic syndrome risk unexpectedly predicted by traditional food consumption: shifting food systems and health among the Awajún of the Peruvian Amazon.

BACKGROUND: Dietary changes, especially declines in traditional food diversity and increases in the consumption of processed foods, have previously been shown to increase the risk of developing cardiovascular diseases. AIM: We evaluated the prevalence and risk factors for metabolic syndrome in four Awajún communities in the Peruvian Amazon. SUBJECTS AND METHODS: A total of 222 participants answered a socioeconomic questionnaire, a 24-h food recall, and completed a physical examination for metabolic syndrome diagnosis. A Poisson regression with robust variance was used in the statistical analysis of risk factors for metabolic syndrome. RESULTS: We found an overall prevalence of 24% for metabolic syndrome. Being female, increased age and body mass index were significant risk factors for metabolic syndrome. Surprisingly, risk more than doubled with the ratio of traditional foods. However, this study revealed that there are fewer traditional foods being consumed in this study compared to prior studies among the Awajún. CONCLUSION: We suggest that the unexpected relationship between traditional food consumption and metabolic syndrome may be due to substantial reductions in the diversity of traditional foods. Currently available traditional foods are primarily high in carbohydrates and are supplemented with cheap, non-perishable, and carbohydrate heavy market food items.

Microscopic and submicroscopic Plasmodium infections in indigenous and non-indigenous communities in Colombia.

BACKGROUND: The indigenous population is considered a highly susceptible group to malaria because individuals usually live in areas with high exposure to Anopheles and poverty, and have limited access to health services. There is a great diversity of indigenous communities in Colombia living in malaria-endemic areas; however, the burden of infection in these populations has not been studied extensively. This study aimed to determine the prevalence of Plasmodium infections in indigenous and non-indigenous communities in two malaria-endemic areas in Colombia. METHODS: A community-based cross-sectional survey was conducted in seven villages of Turbo and El Bagre municipalities; three of these villages were indigenous communities. Inhabitants of all ages willing to participate were included. Sociodemographic and clinical data were recorded as well as household information. The parasitological diagnosis was performed by microscopy and nested PCR. The prevalence of microscopy and submicroscopic infection was estimated. An adjusted GEE model was used to explore risk factors associated with the infection. RESULTS: Among 713 participants, 60.7% were from indigenous communities. Plasmodium spp. was detected in 30 subjects (4.2%, CI 95% 2.9-5.9); from those, 29 were in the indigenous population, 47% of infections were afebrile, and most of them submicroscopic (10/14). Microscopic and submicroscopic prevalence was 2.5% (CI 95% 1.6-3.9) and 1.7% (CI 95% 0.9-2.9), respectively. In El Bagre, all infections occurred in indigenous participants (3.9%, CI 95% 2.2-7.1), and 81% were submicroscopic. By contrast, in Turbo, the highest prevalence occurred in indigenous people (11.5%; CI 95%: 7.3-17.5), but 88.8% were microscopic. Living in an indigenous population increased the prevalence of infection compared with a non-indigenous population (PR 19.4; CI 95% 2.3-166.7). CONCLUSION: There is a high proportion of Plasmodium infection in indigenous communities. A substantial proportion of asymptomatic and submicroscopic carriers were detected. The identification of these infections, not only in indigenous but also in the non-indigenous population, as well as their associated factors, could help to implement specific malaria strategies for each context.

Contrasting the ancestry patterns of three distinct population groups from the northernmost region of South America.

Colombia, located in the north of the South American subcontinent is a country of great interest for population genetic studies given its high ethnic and cultural diversity represented by the admixed population, 102 indigenous peoples and African descent populations. In this study, an analysis of the genetic structure and ancestry was performed based on 46 ancestry informative INDEL markers (AIM-INDELs) and considering the genealogical and demographic variables of 451 unrelated individuals belonging to nine Native American, two African American, and four multiple ancestry populations. Measures of genetic diversity, ancestry components, and genetic substructure were analyzed to build a population model typical of the northernmost part of the South American continent. The model suggests three types of populations: Native American, African American, and multiple ancestry. The results support hypotheses posed by other authors about issues like the peopling of South America and the existence of two types of Native American ancestry. This last finding could be crucial for future research on the peopling of Colombia and South America in that a single origin of all indigenous communities should not be assumed. It then would be necessary to consider other events that could explain their genetic variability and complexity throughout the continent.

The cognitive performance of indigenous schoolchildren in relation to their feeding during infancy.

OBJECTIVES: Nutrition during the first 3 years of life is critical to neurodevelopment. Native populations experience poverty, inequality, and food insecurity. Therefore, we analyzed the relationship between feeding during infancy and cognitive performance in schoolchildren of rural indigenous communities in Riobamba, Ecuador. METHODS: Thirty-seven schoolchildren (5-6 years) were recruited. We determined duration of exclusive breastfeeding, weaning age, age of cow's milk incorporation, daily intake of cow's milk, age of solid and liquid incorporation, and sociocultural and anthropometric parameters. Verbal, manipulative, and total intelligence quotients were evaluated with Wechsler Preschool and Primary Scale of Intelligence. RESULTS: Means of verbal, manipulative, and total intelligence quotient scores were 86.46 ± 11.55, 96.39 ± 9.96, and 89.25 ± 10.43, respectively. Children were exclusively breastfed until 6.83 ± 3.97 months and weaned at 17.17 ± 5.58 months. Age of cow's milk incorporation was 12.58 ± 6.06 months, with a daily intake of 737.50 ± 417.50 mL. Solids were incorporated at 10.11 ± 4.43 months and liquids at 7.72 ± 3.30 months. Positive associations between duration of exclusive breastfeeding and manipulative (unadjusted: ρ = .545, P = .006; r = .491, P = .028; adjusted for children's body mass index, and ethnicity and educational level of mothers: r = .522, P = .041) and total (unadjusted: ρ = .483, P = .017; adjusted: r = .572, P = .036) intelligence quotients were found. Frequency of children with manipulative (χ2 [2] = 7.093, P = .029) and total (χ2 [2] = 7.198, P = .027) intelligence quotient ≥90 was higher in those exclusively breastfed >6 months. Furthermore, schoolchildren in the >6 months group had better manipulative (101.75 ± 9.08 vs 89.71 ± 8.56, P = .038) and total (94.50 ± 11.89 vs 84.86 ± 5.05, P = .036) intelligence quotient than those in the <6 months group, independent of anthropometric and sociocultural factors. CONCLUSIONS: Longer exclusive breastfeeding was related to better total intelligence quotient in rural indigenous schoolchildren.

The Xavante Longitudinal Health Study in Brazil: Objectives, design, and key results.

OBJECTIVE: The Xavante Longitudinal Health Study was developed to permit granular tracking of contemporary health challenges faced by indigenous communities in Brazil, taking into consideration ongoing historical processes that may be associated with increases in child undernutrition, adult obesity, and cardiovascular disease risks. METHODS: This was an open-cohort study with six semiannual data collection waves from 2009 to 2012. The study was undertaken in two Xavante villages, Pimentel Barbosa and Etênhiritipá, State of Mato Grosso, Central Brazil. No sampling technique was used. Data collection placed emphasis on growth and nutrition of children under five and nutrition status, blood pressure, and blood glucose levels of adolescents and adults. RESULTS: Baseline data collection began in July/August 2009 with a population census (656 individuals). Between the first and final waves, the study population increased by 17%. At baseline, stunting and wasting was elevated for most age groups <10 years. Overweight, obesity, and increased risk of metabolic complications were expressive among individuals >17 years, disproportionately affecting females. Anemia was elevated in most age groups, especially among females. Mean systolic and diastolic blood pressure was moderate. The overall prevalence of high blood pressure was relatively low. CONCLUSIONS: Our findings reveal marked health disparities relative to the Brazilian national population and a complex dietary health epidemiology involving the double burden of malnutrition, rapidly changing nutritional indicators, and elevated metabolic disease risk. The topically broad multidisciplinary focus permitted construction of the richest longitudinal data set of socio-epidemiological information for an indigenous population in Brazil.

Relationship of sanitation, water boiling, and mosquito nets to health biomarkers in a rural subsistence population.

OBJECTIVES: Throughout human evolutionary history, parasites and pathogens were a major cause of mortality-modern urban life with public health infrastructure has changed disease exposure. We examine associations between boiling water, using latrines, mosquito net usage, and biomarkers among the Tsimane, a nonindustrial subsistence population with little public health infrastructure. METHODS: We conducted cross sectional surveys on water, latrines, and bed nets among 507 heads of households (aged 18-92 years, median age 41 years). Regression models estimated associations between behaviors and health biomarkers (ie, white blood cell count [WBC], hemoglobin, eosinophil count, and erythrocyte sedimentation rate) adjusting for age, sex, body mass index, wealth, schooling, and distance to the nearby market town. RESULTS: Latrine use is associated with 6.5% lower WBC count (ß = -679.6, P = .031, SE = 314.1), 17.4% lower eosinophil counts (ß = -244.7, P = .023, SE = 107.2), and reduced odds of eosinophilia (adjusted OR = 0.40, P < .019, 95% CI = 0.18-0.86). Boiling water and mosquito net use are not significantly associated with any biomarkers measured. CONCLUSIONS: In a subsistence population currently undergoing epidemiological transition, we find that latrine use was associated with several objective measures of health. This suggests that relatively low cost and low maintenance public health interventions may wish to focus on latrine use, as there is unmet need and potential health benefits for those who use latrines. Additionally, while the cost is higher, public health organizations aimed at improving sanitation may be able to use minimally invasive field-collected biomarkers as a diagnostic to objectively test the efficacy of interventions with greater specificity than anthropometric measurements.

Old friends and friendly fire: Pregnancy, hookworm infection, and anemia among tropical horticulturalists.

OBJECTIVES: Despite public health concerns about hookworm infection in pregnancy, little is known about immune profiles associated with hookworm (Necator americanus and Ancylostoma duodenale) infection during pregnancy. Fetal tolerance requirements may constrain maternal immune response to hookworm, thereby increasing susceptibility to new infections or increasing hemoglobin loss. To explore this possibility, we study systemic immune response and hemoglobin levels in a natural fertility population with endemic helminthic infection. METHODS: We used Bayesian multilevel models to analyze mixed longitudinal data on hemoglobin, hookworm infection, reproductive state, eosinophils, and erythrocyte sedimentation rate (ESR) to examine the effects of pregnancy and hookworm infection on nonspecific inflammation, cellular parasite response, and hemoglobin among 612 Tsimane women aged 15-45 (1016 observations). RESULTS: Pregnancy is associated with lower eosinophil counts and lower eosinophil response to hookworm, particularly during the second and third trimesters. Both hookworm and pregnancy are associated with higher ESR, with evidence for an interaction between the two causing further increases in the first trimester. Pregnancy is moderately associated with higher odds of hookworm infection (OR: 1.23, 95% CI: 0.83 to 1.83). Pregnancy and hookworm both decrease hemoglobin and may interact to accentuate this effect in the first-trimester of pregnancy (Interaction: ß: -0.30 g/dL; CI: -0.870 to 0.24). CONCLUSIONS: Our findings are consistent with a possible trade-off between hookworm immunity and successful pregnancy, and with the suggestion that hookworm and pregnancy may have synergistic effects, particularly in the first trimester.

[Reduction of HBV and HDV infection in two indigenousmpeoples of Peruvian Amazon after the vaccination against hepatitis B]. / Reducción en la infección por VHB y VHD en dos poblaciones indígenas de la Amazonia peruana después de la vacunación contra la hepatitis B.

OBJECTIVE: To determine the outcome of the vaccination against hepatitis, we determined the prevalence of hepatitis B virus (HBV) and hepatitis D virus (HDV) infections, eight years after introduction of the vaccination. MATERIALS AND METHODS: A cross-sectional study was performed in 2 944 participants of 67 Kandozi and Chapra indigenous peoples in April 2010. Serological screening for hepatitis B surface antigen (HBsAg), antibody anti-HBc IgM and IgG, antibody anti-HBs and anti-HDV were determined by ELISA tests. RESULTS: The prevalence rates of HBsAg, anti-HBc total, anti- HBs ≥10 mlUI/ml and anti-HDV were 2.3, 39.13, 50.95 and 2.11%, respectively. The prevalence rate of HBsAg in children <11 years was 0%. Among carriers of HBsAg, the prevalence rates of HDV and acute HBV infections were 2.11% (all were >14 years) and 11.94%, respectively. HBsAg and anti-HBc total were associated with individuals ≥10 years (p<0.001). CONCLUSIONS: These findings show the elimination of HBVmcarriers in children <11 years, eight years following introduction of the vaccination against HBV.

OBJETIVO: Conocer el resultado de la vacunación contra la hepatitis B en las comunidades hiperendémicas Kandozi y Chapra de la Amazonia Peruana a partir de la prevalencia de infecciones por los virus de la hepatitis B (VHB) y Delta (VHD), ocho años después de iniciada la vacunación. MATERIAL Y MÉTODOS: Se realizó un estudio transversal en 2 944 pobladores de 67 comunidades indígenas Kandozi y Chapra en abril de 2010. El tamizaje serológico para el antígeno de superficie del VHB (HBsAg), anticuerpos anti-HBc IgM e IgG, anticuerpos anti-HBs y anti-VHD se determinaron mediante pruebas de ELISA. RESULTADOS: Las tasas de prevalencia del HBsAg, anti-HBc IgG, anti-HBs ≥10 mlUI/ml y anti-VHD fueron 2.3, 39.13, 50.95 y 2.11%, respectivamente. La prevalencia del HBsAg en niños <11 años fue cero. Entre los portadores del HBsAg, las tasas de prevalencia de sobreinfeccion por el VHD e infección aguda por el VHB fueron 2.11% (todos fueron >14 años) y 11.94%, respectivamente. CONCLUSIONES: Estos hallazgos muestran la eliminación de portadores de VHB en niños <11 años, ocho años después de iniciada la vacunación contra el VHB.

Evaluating elbow osteoarthritis within the prehistoric Tiwanaku state using generalized estimating equations (GEE).

OBJECTIVES: Studies of osteoarthritis (OA) in human skeletal remains can come with scalar problems. If OA measurement is noted as present or absent in one joint, like the elbow, results may not identify specific articular pathology data and the sample size may be insufficient to address research questions. If calculated on a per data point basis (i.e., each articular surface within a joint), results may prove too data heavy to comprehensively understand arthritic changes, or one individual with multiple positive scores may skew results and violate the data independence required for statistical tests. The objective of this article is to show that the statistical methodology Generalized Estimating Equations (GEE) can solve scalar issues in bioarchaeological studies. MATERIALS AND METHODS: Using GEE, a population-averaged statistical model, 1,195 adults from the core and one colony of the prehistoric Tiwanaku state (AD 500-1,100) were evaluated bilaterally for OA on the seven articular surfaces of the elbow joint. RESULTS: GEE linked the articular surfaces within each individual specimen, permitting the largest possible unbiased dataset, and showed significant differences between core and colony Tiwanaku peoples in the overall elbow joint, while also pinpointing specific articular surfaces with OA. Data groupings by sex and age at death also demonstrated significant variation. A pattern of elbow rotation noted for core Tiwanaku people may indicate a specific pattern of movement. DISCUSSION: GEE is effective and should be encouraged in bioarchaeological studies as a way to address scalar issues and to retain all pathology information.

Crypt fenestration enamel defects and early life stress: Contextual explorations of growth and mortality in Colonial Peru.

OBJECTIVES: This study provides a comprehensive analysis of crypt fenestration enamel defects (CFEDs) from the Eten and Mórrope communities, Colonial period (A.D. 1,530-1,750), Lambayeque Valley, Peru. The goal is to help clarify the role of these lesions as reflections of early life environments as well as relationships growth and survival at future ages. MATERIALS AND METHODS: CFED absence/presence was recorded in the mandibular canines of 105 individuals and 202 teeth. Defect prevalence was compared between the Eten and Mórrope sites using a proportions test. Femoral growth residuals were compared between CFED present and absent samples. Mortality risk was evaluated using Kaplan-Meier survival analysis. RESULTS: CFED frequencies at Eten and Mórrope were similar to previous studies. Greater frequencies of CFEDs were found at Eten compared to Mórrope. There was no association between skeletal growth and CFEDs. No differences in mortality were found between CFED present and absent individuals within each site. General survivorship at Eten was significantly greater than Mórrope. However, individuals without CFEDs at Eten had greater survivorship than those with and without CFEDs at Mórrope. Individuals with CFEDs at Eten had greater survivorship than those with CFEDs at Mórrope. These differences begin around 1.7 years. CONCLUSIONS: CFEDs may be associated with stress experience, but associations with growth and survivorship at later ages is context dependent. CFED prevalence is an ambiguous indicator of stress when used in the absence of mortality data, and even under those circumstances, appears limited by differences in local demography.

Low sleep time is associated with higher levels of blood pressure and fat mass in Amerindian schoolchildren.

OBJECTIVES: While altered sleep patterns (ie, low sleep time) have been studied and reported in adults as a new cardiometabolic risk factor, less information is available on how sleep patterns impact children of different ethnicities. The aim of this study was to compare the levels of blood pressure and other cardiometabolic risk factors in relation to different levels of sleep time in schoolchildren of Amerindian Mapuche or European-ancestry of Southern Chile. METHODS: In a cross-sectional study, 540 Chilean schoolchildren (6-13 years) were divided into two ethnic groups (n = 119 Mapuche Amerindians and n = 421 European-ancestry). Groups were analyzed according to sleep time per day as registered by parents' report and distributed into quartile categories of sleep time: Mapuche (quartile 1 [Q1] ≥10.0 h, n = 34; Q2 9.5-10.0 h, n = 29; Q3 8.5-9.0 h, n = 31; and Q4 ≤ 8.5 h, n = 25), and European (Q1, n = 99; Q2, n = 77; Q3, n = 144; Q4, n = 101). The main cardiovascular parameters (systolic [SBP] and diastolic blood pressure) were complemented with anthropometric/body composition (body mass, body mass index [BMI], waist circumference, fat mass, muscle mass, lean mass), cardiorespiratory (heart rate rest, oxygen saturation), and muscle strength (handgrip of dominant and non-dominant arm) outcomes. RESULTS: From Q1 and across Q2, Q3, and Q4, there was an increase in delta mean SBP in both Mapuche (Δ +17.6 mm Hg) and European (Δ +7.3 mm Hg) schoolchildren with 30-90 min of decreased sleep time (using ≥10 h as reference in Q1). The tendency for worsening of other cardiometabolic risk factors was maintained for delta mean BMI (Δ +2.6 kg/m2 ), waist circumference (Δ +12 cm), and fat mass (Δ +8.3%) in Mapuches, whereas European peers showed only worsened waist circumference (Δ +6 cm) across Q2, Q3, and Q4 in comparison with reference Q1. There was also a higher prevalence of hypertension in Mapuche (31.1%) compared to in European schoolchildren (17.6%). CONCLUSIONS: Mapuche and European schoolchildren show higher levels of SBP with a decrease in sleep time of 30 min; however, there is a higher prevalence of hypertension and obesity in ethnic Mapuches than in European schoolchildren. These findings indicate that more studies should be applied at early school ages for preventing low sleep time and their related cardiometabolic risk factors for hypertension development in different ethnic groups.

Non-high-density lipoprotein cholesterol curves in Argentinean indigenous children living at high altitude and US children.

OBJECTIVE: To describe the non-high-density lipoprotein cholesterol (non-HDL-C) as mean and percentiles by age and sex in Argentinean indigenous schoolchildren living at 3750 m, contrasting these estimates with those reported in the 2011-2012 National Center for Health Statistics reference population (NHANES). METHODS: Non-HDL-C was calculated as total cholesterol-HDL-C. Analyses incorporated sampling weights for age and sex to obtain unbiased estimates. Sex- and age-specific smoothed percentile curves were performed with Cole's LMS method. RESULTS: A total of 236 (49% males) children from San Antonio de los Cobres (SAC) were evaluated twice and compared with 1409 NHANES children. Non-HDL-C values were 4 mg/dL higher in SAC than in NHANES (109 vs 105 mg/dL, respectively). Trends in non-HDL-C 50th percentile in females differed between ages 6 to 7 and 8 years; in SAC non-HDL-C decreased from 111 to 104 mg/dL, NHANES levels remained stable from103 to 104 mg/dL. Among children aged 9 to10 years, non-HDL-C increased from 114 mg/dL to 117 mg/dL in SAC, but decreased from 113 to 107 mg/dL in NHANES. Between ages 12 and 13 years, non-HDL-C increased from 108 to 120 mg/dL in SAC, and remained steady from105 to 106 mg/dL in NHANES. The 50th percentile of non-HDL-C in males showed similar trends except for ages 6 to 7 to age 8 when non-HDL-C remained stable from 106 to 107 mg/dL in SAC, and increased from 98 mg/dL to 104 mg/dL in NHANES. CONCLUSIONS: Non-HDL-C levels in children vary with age, sex, ethnicity, and altitude. Different patterns in non-HDL-C were observed for girls in SAC compared with NHANES. However, more stable patterns were observed in boys in both groups.

Secular trends in adult stature among the Makushi of Guyana in the 20th Century.

OBJECTIVE: This study describes secular trends in physical stature, Cormic Index (CI), and body mass index (BMI) of adult Makushi Amerindians born between 1910 and 1980, compares the stature of these Makushi adults to Makushi adults measured in 1921, and provides contextual data to inform the findings. METHODS: Pearson's correlation was used to assess the relationship between year of birth and physical stature, BMI, and CI for 231 females and 113 males, 20 to 90 years of age measured in 2000 to 2001. Wilcoxon's test was used to compare physical stature of Makushi adults measured in 2000 to 2001 with that of 40 Makushi adults measured in 1921. RESULTS: Among Makushi measured in 2000 to 2001, females and males born more recently were taller and had a lower CI but did not differ in BMI relative to their elders. Makushi measured in 2000 to 2001 are significantly taller than those Maksuhi measured in 1921. CONCLUSION: The increased physical stature of and decreased CI in more recently born Makushi may be explained by a more favorable early life environment possibly due to public health measures and dietary changes. As well, trends in stature may be linked to genetic admixture with African-Guyanese migrating into the region during this time.

Testosterone is positively and estradiol negatively associated with mucosal immunity in Amazonian adolescents.

OBJECTIVES: A core assumption of life history theory and the immunocompetence handicap hypothesis (ICHH) is that testosterone (T) upregulates energetic investment in mating effort at the expense of immunity. This tenet, along with observed positive relationships between estrogens and immunity, may contribute to the higher observed morbidity and mortality of males. In the present study, we examine the association between sex steroid hormones and mucosal immunity as well as sex differences in immunity in a rural Amazonian population of immune-challenged Bolivian adolescents. METHODS: Salivary steroid hormones (T [males only] and estradiol [E2 , females only]), Tsimane-specific age-standardized BMI z-scores, and salivary mucosal immunity (sIgA, secretory IgA) were measured in 89 adolescent males and females. RESULTS: Males had significantly higher sIgA levels than females, which may be due to the observed immune-endocrine associations found in the present study. Controlling for age and phenotypic condition, higher T significantly predicted higher sIgA; whereas higher E2 was associated with lower sIgA in females. CONCLUSIONS: Results stood in contrast to common interpretations of the ICHH, that is, that T should be inversely associated with immunity. Findings from the present study support the notion that the endocrine system likely affects immunity in a regulatory fashion, upregulating certain aspects of immunity while downregulating others. An important remaining question is the adaptive reason(s) for sex differences in endocrine-mediated immuno-redistribution.