RESUMO
This study compares blood pressure (BP) and related cardiovascular risk factors among three Caboclo communities from the Brazilian Amazon. Its purpose is to investigate possible risk differentials related to variable ecological settings and Western influences. Caxiuanã is characterized as a more "traditional" group, while Aracampina and Santana are viewed as more "transitional" in lifestyle. A total of 348 subjects from the three communities were evaluated in the wet or the dry season or in both. Measurements across the communities were compared by season and sex. Results suggest little seasonal variation in average BP, BP change, body fat, or body fat change among men. Conversely, there is substantial seasonal and inter-community variation among women. Additional analyses reveal (1) an inconsistent association between age and BP across the communities; (2) that BMI is not associated with BP transitional communities in either season but is associated with both systolic and diastolic pressure in the most traditional community; and (3) little to no sex effect on BP. These results suggest increased Western influence affects body composition particularly of women. However, increased BMI and fat among transitional Caboclo women does not directly translate into higher BP; rather, their BP appears to be more affected by seasonal stresses. Finally, conditions during the wet season diminish age-related variation in BP, suggesting that during the wet season these Caboclo may be less active.
Assuntos
Tecido Adiposo/fisiologia , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Indígenas Sul-Americanos , Adulto , Análise de Variância , Antropometria , Índice de Massa Corporal , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Estações do AnoRESUMO
Native Americans have been classified into four founding haplogroups with as many as seven founding lineages based on mtDNA RFLPs and DNA sequence data. mtDNA analysis was completed for 83 Yanomami from eight villages in the Surucucu and Catrimani Plateau regions of Roraima in northwestern Brazil. Samples were typed for 15 polymorphic mtDNA sites (14 RFLP sites and 1 deletion site), and a subset was sequenced for both hypervariable regions of the mitochondrial D-loop. Substantial mitochondrial diversity was detected among the Yanomami, five of seven accepted founding haplotypes and three others were observed. Of the 83 samples, 4 (4.8%) were lineage B1, 1 (1.2%) was lineage B2, 31 (37.4%) were lineage C1, 29 (34.9%) were lineage C2, 2 (2.4%) were lineage D1, 6 (7.2%) were lineage D2, 7 (8.4%) were a haplotype we designated "X6," and 3 (3.6%) were a haplotype we designated "X7." Sequence analysis found 43 haplotypes in 50 samples. B2, X6, and X7 are previously unrecognized mitochondrial founding lineage types of Native Americans. The widespread distribution of these haplotypes in the New World and Asia provides support for declaring these lineages to be New World founding types.
Assuntos
DNA Mitocondrial , Evolução Molecular , Variação Genética , Indígenas Sul-Americanos/genética , Adulto , Brasil , DNA Mitocondrial/genética , DNA Mitocondrial/história , Emigração e Imigração/história , Feminino , Efeito Fundador , Haplótipos , História Antiga , Humanos , Indígenas Sul-Americanos/história , Masculino , Polimorfismo de Fragmento de RestriçãoRESUMO
Using isoelectric focusing and immunoblotting techniques, we screened 96 serum samples from Yanomami Indians of northwestern Brazil to determine structural variation at three apolipoprotein loci: A4, E, and H. The APO-H locus, which is commonly polymorphic in white and black samples, was found to be monomorphic. At the APO-E locus only two alleles, APOE*3 and APOE*4, rather than the three-allele polymorphism commonly seen in Caucasians, was observed. At the APO-A4 locus no example of the APOA4*2 allele, found in Caucasians, was detected. However, the frequency of the less common APOA4*4 allele was above what has been observed in any other population. We investigated the impact of genetic variation at both polymorphic loci on quantitative differences in lipids, apolipoproteins, serum glucose, glycated hemoglobin, and uric acid. Contrary to the cholesterol-elevating effect of APOE*4 reported elsewhere, in both univariate analyses and after adjustments for age, sex, weight, and height, APOE*4 was associated with about a 4% lower mean serum cholesterol. Only after adjustment was this association statistically significant. The APOE*4 allele was significantly associated with unadjusted APO-A1 and APO-E levels but not with any other dependent variable; associations with adjusted APO-A1, APO-C2, and uric acid also approached standard levels of statistical significance (p < or = 0.05). In univariate analyses the APOA4*4 allele was significantly associated with APO-B, serum glucose, percent glycated hemoglobin, and uric acid, but no significant associations were observed after dependent variables were adjusted for age, sex, weight, and height. These results support the notion that apolipoprotein distributions and their associations with lipid and carbohydrate metabolism show ethnic variability.
Assuntos
Apolipoproteínas A/genética , Apolipoproteínas E/genética , Frequência do Gene , Variação Genética/genética , Glicoproteínas/genética , Indígenas Sul-Americanos/genética , Polimorfismo Genético , Adulto , Brasil , Metabolismo dos Carboidratos , Carboidratos/sangue , Colesterol/sangue , Colesterol/genética , Dieta , Feminino , Humanos , Lipoproteínas/sangue , Lipoproteínas/genética , Masculino , Polimorfismo Genético/genética , beta 2-Glicoproteína IRESUMO
We determined associations of measures of body habitus with blood pressure for 100 adult Yanomami Indians (61 men, 39 women) examined during February and March 1990. Measurements included body weight and height, four skinfolds (triceps, subscapular, suprailiac, abdomen), four circumferences (wrist, upper arm, abdomen, hip), systolic and diastolic blood pressures, pulse rate, and estimated age. Various indices of fat distribution were determined from the measurements of skinfolds, circumferences, weight, and height. Estimated age averaged 35.0 years in men and 33.4 years in women (range: 15 to 63 years). Mean systolic and diastolic blood pressures were low in both men (104.8/70.4 mm Hg) and women (94.8/63.5 mm Hg), as was body mass index (men: 20.7; women: 21.4 kg/m2). In Yanomami women, all four skinfolds, wrist circumference, and the indices of hip and abdominal fat were significant correlates of systolic blood pressure, while the abdominal skinfold and wrist and hip circumferences correlated significantly with diastolic blood pressure. Among men, there was a negative correlation between estimated age and systolic blood pressure and a positive correlation between BMI and upper arm and hip circumferences and systolic blood pressure. There was a significant positive correlation between wrist, upper arm, and hip circumferences and diastolic blood pressure among Yanomami men. We used stepwise regression to generate sex-specific predictive equations for blood pressure. For men, estimated age and hip circumference, and for women, abdominal skinfold measurement and age were included in the model for systolic blood pressure. Among men, wrist circumference and height, and among women, wrist circumference alone entered the model for diastolic blood pressure. On the basis of these results, we suggest that even in a low-blood pressure, low-body fat, no-salt setting, systolic blood pressure is associated with the amount and placement of adipose tissue. However, diastolic blood pressure is more closely correlated with skeletal size.
Assuntos
Pressão Sanguínea/fisiologia , Indígenas Sul-Americanos , Adolescente , Adulto , Fatores Etários , Antropometria , Peso Corporal , Brasil/epidemiologia , Dieta Hipossódica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores SexuaisRESUMO
To determine serum lipid levels and their correlates in one of the world's most isolated populations, 62 adult Yanomamo Indians from the Amazonian rain forest were examined. After measurement of body weight and height, and estimation of age, casual blood samples were obtained. Estimated age ranged from 20 to 68 years, with men averaging 37 and women 35 years. Mean serum total cholesterol was very low among both men (123 mg/dl) and women (142 mg/dl) compared with western samples, whereas triglycerides--112 and 110 mg/dl, respectively--were lower among men and slightly higher among women than for U.S. men and women. Yanomamo women had significantly higher total cholesterol (P = 0.02) and body mass index (BMI) (P = 0.05) than men. HDL-cholesterol (P = 0.08) and LDL-cholesterol (P = 0.21) were also somewhat higher among women. Multivariate regression analysis indicated that estimated age was independently related to cholesterol in both sexes, while BMI was of borderline significance. The very low serum lipid levels in this isolated population are apparently attributable mainly to their largely vegetarian diet, low in fats and cholesterol and high in fiber, with concomitant high physical activity associated with low BMI.