Cardiovascular Risk in Xavante Indigenous Population.

BACKGROUND: The prevalence of cardiovascular risk factors is little known in Brazilian indigenous populations. In the last two decades, important changes have occurred in the lifestyle and epidemiological profile of the Xavante people. OBJECTIVE: to assess the prevalence of cardiovascular risk factors in Xavante adults in São Marcos and Sangradouro/Volta Grande reserves, in the state of Mato Grosso, Brazil. METHODS: Cross-sectional study carried out with 925 Xavante people aged ≥ 20 years between 2008 and 2012. The following indicators were assessed: triglycerides (TG), total, LDL and HDL-cholesterol, Castelli index I and II, TG/HDL-cholesterol ratio, apo B / Apo A1 ratio, Framingham risk score, C-reactive protein, body mass index (BMI), waist circumference (WC), hypertriglyceridemic waist (HW), glycemia and blood pressure. Kolmogorov-Smirnov, Student's t test and Chi-square test (χ2) were used for statistical analysis, and significance level was set at 5%. RESULTS: High prevalence of elevated cardiovascular risk was observed in men and women according to HDL-cholesterol (66.2% and 86.2%, respectively), TG (53.2% and 51.5%), TG/HDL-cholesterol ratio (60.0% and 49.1%), C-reactive protein (44.1% and 48.1%), BMI (81.3% and 81.7%), WC (59.1% and 96.2%), HW (38.0% and 50,6%) and glycemia (46.8% and 70.2%). Individuals aged 40 to 59 years had the highest cardiovascular risk. CONCLUSIONS: The Xavante have a high cardiovascular risk according to several indicators evaluated. The present analysis of cardiovascular risk factors provides support for the development of preventive measures and early treatment, in attempt to minimize the impact of cardiovascular diseases on this population.

Cardiovascular Risk in Xavante Indigenous Population / Risco Cardiovascular na População Indígena Xavante

Abstract Background: The prevalence of cardiovascular risk factors is little known in Brazilian indigenous populations. In the last two decades, important changes have occurred in the lifestyle and epidemiological profile of the Xavante people. Objective: to assess the prevalence of cardiovascular risk factors in Xavante adults in São Marcos and Sangradouro/Volta Grande reserves, in the state of Mato Grosso, Brazil. Methods: Cross-sectional study carried out with 925 Xavante people aged ≥ 20 years between 2008 and 2012. The following indicators were assessed: triglycerides (TG), total, LDL and HDL-cholesterol, Castelli index I and II, TG/HDL-cholesterol ratio, apo B / Apo A1 ratio, Framingham risk score, C-reactive protein, body mass index (BMI), waist circumference (WC), hypertriglyceridemic waist (HW), glycemia and blood pressure. Kolmogorov-Smirnov, Student's t test and Chi-square test (χ2) were used for statistical analysis, and significance level was set at 5%. Results: High prevalence of elevated cardiovascular risk was observed in men and women according to HDL-cholesterol (66.2% and 86.2%, respectively), TG (53.2% and 51.5%), TG/HDL-cholesterol ratio (60.0% and 49.1%), C-reactive protein (44.1% and 48.1%), BMI (81.3% and 81.7%), WC (59.1% and 96.2%), HW (38.0% and 50,6%) and glycemia (46.8% and 70.2%). Individuals aged 40 to 59 years had the highest cardiovascular risk. Conclusions: The Xavante have a high cardiovascular risk according to several indicators evaluated. The present analysis of cardiovascular risk factors provides support for the development of preventive measures and early treatment, in attempt to minimize the impact of cardiovascular diseases on this population.

Resumo Fundamento: A prevalência de fatores de risco cardiovascular ainda é pouco estudada em populações indígenas brasileiras. Nas duas últimas décadas, observaram- se importantes mudanças no estilo de vida e no perfil epidemiológico dos Xavante. Objetivo: Avaliar a prevalência de fatores de risco cardiovascular na população adulta Xavante das Reservas Indígenas de São Marcos e Sangradouro/Volta Grande - MT. Métodos: Estudo transversal realizado com 925 indígenas Xavante com 20 ou mais anos de idade, no período de 2008 a 2012. Foram considerados os indicadores: níveis séricos de triglicérides (TG), colesterol (total, LDL e HDL), Índices de Castelli I (CT/HDL-c) e II (LDL-c/HDL-c), razão TG/HDL-C, relação Apo B/Apo A1, escore de Framingham, proteína C reativa (PCR), Índice de Massa Corporal (IMC), circunferência da cintura (CC), cintura hipertrigliceridêmica (CH), glicemia e pressão arterial. Foram utilizados os testes Kolmogorov-Smirnov, t de Student e Qui quadrado (χ2), sendo considerado um nível de significância de 5%. Resultados: Verificaram-se altas prevalências de risco cardiovascular elevado, em homens e mulheres, respectivamente, segundo os indicadores HDL-colesterol (66,2% e 86,2%), TG (53,2% e 51,5%), razão TG/HDL-c (60,0% e 49,1%), PCR (44,1% e 48,1%), IMC (81,3% e 81,7%), CC (59,1% e 96,2%), CH (38,0% e 50,6%) e glicemia (46,8% e 70,2%). Os indivíduos de 40 a 59 anos foram os que apresentaram maior risco cardiovascular. Conclusões: Os Xavante apresentam elevado risco cardiovascular segundo vários indicadores avaliados. Este inquérito fornece subsídios para ações de prevenção e tratamento precoce, a fim de minimizar os potenciais danos causados por doenças cardiovasculares entre os Xavante.

Prevalence of metabolic syndrome in the Brazilian Xavante indigenous population.

BACKGROUND: The raising prevalence of weight excess and of non-communicable diseases in indigenous populations, as well as changes in food consumption and reduction in the frequency and intensity of physical activity, suggest that the prevalence of metabolic syndrome (MS) is also elevated. The objective of this study was to evaluate the prevalence of MS and the frequency of its components in the Xavante adult population living in the Indian reservations of São Marcos and Sangradouro/Volta Grande, in the state of Mato Grosso, Brazil. A cross-sectional study was carried out among 932 Xavante Indians aged 20 years or more, in the 2008-2012 period. The variables analysed were gender, age, weight, height, waist circumference, blood pressure, initial and 2-h capillary glycemia in a 75 g OGTT, levels of triglycerides and HDL-cholesterol. The diagnostic criteria for MS proposed by the IDF and AHA/NHLBI were used. RESULTS: The prevalence of MS was 66.1 % (95 % CI 63.0-69.2), being 76.2 % (95 % CI 72.4-80.0) in women and 55.6 % (95 % CI 51.0-60.2) in men. Women had higher prevalence of MS in all age groups. Elevated waist circumference and lower levels of HDL-cholesterol were the more frequent components in those with MS, and elevated blood pressure was the less frequent. CONCLUSIONS: The high prevalence of MS in the Xavante Indians is mainly due to the increased prevalence of weight excess that resulted from an intense change in their life-style, in a short period of time in a population with a genetic predisposition. These findings highlight the magnitude of this health problem and make an alert about the necessity to implement specific preventive interventions.

High prevalence of type 2 diabetes mellitus in Xavante Indians from Mato Grosso, Brazil.

OBJECTIVE: To estimate the prevalence of diabetes, hypertension, obesity, and describe demographic, anthropometric and medical characteristics, in a genetically distinct population: the Brazilian Xavante Indians. DESIGN: Population-based survey carried out among 948 Xavante from Mato Grosso, Brazil. Fasting and 2-hour after 75 g glucose capillary glycemia were measured by a portable glucometer (HemoCue Glucose201+). Diabetes was defined according to WHO criteria. Anthropometric data and medical characteristics were measured, and fat mass (%) was evaluated using bioelectrical impedance. Blood pressure was measured by an automated device (OMRON 742INTC), and hypertension was defined according to WHO criteria. RESULTS: Age-adjusted prevalence rates with 95% confidence intervals were diabetes: 28.2% (25.3-31.1) in general, 18.4% (14.9-22.2) in men and 40.6% (36.2-45.1) in women (P<.001); impaired glucose tolerance: 32.3% (20.5-26.0) in general, 29.7% (25.4-33.9) in men and 34.4% (30.2-38.8) in women (P>.05); hypertension: 17.5% (15.1-19.9) in general. Obesity was found in 50.8% of the individuals. Fat mass (%) was associated with diabetes in men (P<.05) and women (P<.05). Thigh circumference and waist/ thigh ratio were lower in those with diabetes, in men and women (P<.001). CONCLUSIONS: The high prevalence of diabetes and obesity in Xavante is likely related to their recent change in food habits and physical activities. Our results should raise awareness about the magnitude of this health problem and also indicate that it could increase dramatically in the future if no preventive actions are adopted.

Evaluation of body adiposity index (BAI) to estimate percent body fat in an indigenous population.

BACKGROUND & AIMS: The aim of this study was to evaluate the usefulness of Body Adiposity Index (BAI) as a predictor of body fat in Xavante Indians and to investigate which anthropometric measures of adiposity best correlate with body fat in this population. METHODS: We evaluated 974 individuals (476 male), aged 42.3 ± 19.5 years. Percentage of body fat (%BF) determined by bioimpedance analysis (BIA) was used as the reference measure of adiposity. Bland-Altman analysis was used to assess the agreement between the two methods: BAI and BIA. Associations between anthropometric measures of adiposity were investigated by Pearson correlation analysis. RESULTS: BAI overestimates %BF (mean difference: 4.10%), mainly at lower levels of adiposity. Significant correlations were found between %BF and all measurements, being the strongest correlation with BAI. However, stratified analyses according to gender showed that among men waist circumference has the strongest correlation (r = 0.73, p < 0.001) and among women BAI (r = 0.71, p < 0.001), BMI (r = 0.69, p < 0.001) and waist circumference (r = 0.70, p < 0.001) performed similarly. CONCLUSION: BAI can be a useful tool to predict %BF in Xavante Indians, although it has some limitations. However, it is not a better predictor of adiposity than waist circumference in men or BMI and waist circumference in women.

Genome-wide analysis in Brazilian Xavante Indians reveals low degree of admixture.

Characterization of population genetic variation and structure can be used as tools for research in human genetics and population isolates are of great interest. The aim of the present study was to characterize the genetic structure of Xavante Indians and compare it with other populations. The Xavante, an indigenous population living in Brazilian Central Plateau, is one of the largest native groups in Brazil. A subset of 53 unrelated subjects was selected from the initial sample of 300 Xavante Indians. Using 86,197 markers, Xavante were compared with all populations of HapMap Phase III and HGDP-CEPH projects and with a Southeast Brazilian population sample to establish its population structure. Principal Components Analysis showed that the Xavante Indians are concentrated in the Amerindian axis near other populations of known Amerindian ancestry such as Karitiana, Pima, Surui and Maya and a low degree of genetic admixture was observed. This is consistent with the historical records of bottlenecks experience and cultural isolation. By calculating pair-wise F(st) statistics we characterized the genetic differentiation between Xavante Indians and representative populations of the HapMap and from HGDP-CEPH project. We found that the genetic differentiation between Xavante Indians and populations of Ameridian, Asian, European, and African ancestry increased progressively. Our results indicate that the Xavante is a population that remained genetically isolated over the past decades and can offer advantages for genome-wide mapping studies of inherited disorders.

Prevalence of HIV infection in patients hospitalized for tuberculosis in Bahia, Brazil.

HIV infection is an important risk factor for the development of tuberculosis (TB), and also affects its morbidity and mortality. This study estimated the prevalence of HIV infection in patients hospitalized for TB in Bahia (in northeastern Brazil) and to evaluate its impact on in-hospital mortality. A total of 375 patients with TB, admitted consecutively to a TB reference hospital in Salvador (Bahia, Brazil), were evaluated between July 2001 and July 2003. Anti-HIV serology was performed in all patients irrespective of clinical and/or epidemiological data suggestive of HIV infection. Death during hospitalization was the principal event-dependent variable. Mean age of patients was 41.4 +/- 16.2 years and the male/female ratio was 3.4:1.0. The prevalence of HIV infection was 8.8% (95%CI: 6.2-12.0%). Patients in the HIV-positive group were younger than those in the HIV-negative group (37.1 versus 41.9 years; p=0.05). In-hospital mortality was 10.9% for the whole group (95%CI: 9.4-15.9%), but was significantly greater in the HIV-positive group compared to the HIV-negative group (27.3% versus 9.4%; RR=2.9; 95%CI: 1.5-5.6; p=0.002). The prevalence of HIV infection in patients hospitalized for TB in Bahia (northeastern Brazil) is relatively high (8.8%) and mortality is significantly higher (2.9-fold) in the HIV-positive group. These findings justify carrying out HIV testing, as recommended by the Brazilian Ministry of Health, in all TB patients, particularly those requiring hospitalization.

Prevalence of HIV infection in patients hospitalized for tuberculosis in Bahia, Brazil

HIV infection is an important risk factor for the development of tuberculosis (TB), and also affects its morbidity and mortality. This study estimated the prevalence of HIV infection in patients hospitalized for TB in Bahia (in northeastern Brazil) and to evaluate its impact on in-hospital mortality. A total of 375 patients with TB, admitted consecutively to a TB reference hospital in Salvador (Bahia, Brazil), were evaluated between July 2001 and July 2003. Anti-HIV serology was performed in all patients irrespective of clinical and/or epidemiological data suggestive of HIV infection. Death during hospitalization was the principal event-dependent variable. Mean age of patients was 41.4 ± 16.2 years and the male/female ratio was 3.4:1.0. The prevalence of HIV infection was 8.8 percent (95 percentCI: 6.2-12.0 percent). Patients in the HIV-positive group were younger than those in the HIV-negative group (37.1 versus 41.9 years; p=0.05). In-hospital mortality was 10.9 percent for the whole group (95 percentCI: 9.4-15.9 percent), but was significantly greater in the HIV-positive group compared to the HIV-negative group (27.3 percent versus 9.4 percent; RR=2.9; 95 percentCI: 1.5-5.6; p=0.002). The prevalence of HIV infection in patients hospitalized for TB in Bahia (northeastern Brazil) is relatively high (8.8 percent) and mortality is significantly higher (2.9-fold) in the HIV-positive group. These findings justify carrying out HIV testing, as recommended by the Brazilian Ministry of Health, in all TB patients, particularly those requiring hospitalization.