Fatores de risco para câncer de mama em mulheres indígenas Teréna de área rural, Estado do Mato Grosso do Sul, Brasil

Abstract

Com o objetivo de se avaliar a distribuição de fatores de risco em mulheres indígenas Teréna no Estado do Mato Grosso do Sul, duas amostras destas foram entrevistadas, respectivamente em 1995 (330 mulheres voluntárias de dez aldeias teréna de área rural) e em 1997 (quarenta mulheres da Aldeia de Limão Verde). Os padrões de vida reprodutiva, dieta, antecedentes patológicos pessoais e familiares foram levantados, bem como a determinação do índice de massa corporal (IMC). Na maior amostra, observou-se que a idade média à menarca foi de 12,3 anos (30% das mulheres referindo-a aos 13 anos ou mais), 86% das mulheres com antecedentes de uma ou mais gestações (42% com cinco ou mais), 71% com antecedentes de três ou mais gestações, idade média à primeira gestação de 18,9 anos (3.8% com 28 anos ou mais), aleitamento materno com duração média de 84 meses, e 70% das mulheres menopausadas antes dos cinqüenta anos de idade. O padrão referido de dieta na menor amostra revela elevado consumo de frutas, legumes, raízes e macarrão, com ingestão escassa de carne vermelha e frango, observando-se que 50% (IC 95%: 34.1-65.9) das mulheres apresentaram sobrepeso (IMC 25-29) e 27% (IC 95%: 15.1-44.1) obesidade (IMC > 29).

Mammographic density among indigenous women in forested areas in the state of Amapá, Brazil: a cross-sectional study

“…However, absence of breast cancer among the indigenous women of several Brazilian states, such as Mato Grosso, Mato Grosso do Sul and Paraná, has been reported in the literature. 3,6,7 The National Health Foundation (FUNASA) keeps up-to-date records of the diseases that occur in the indigenous population, which undermines the hypothesis that underreporting is responsible for non-registration of cases of breast cancer among indigenous women in Brazil. 13 In the international lit- 21 In all of these studies, lower breast density was associated with lower incidence of breast cancer.…”

“…3,21,27 Reproductive behavior is quite different in indigenous populations, and this probably contributes towards creating a protective effect against breast cancer. This, together with other factors, might explain the low incidence of this disease among these women.…”

“…Both in our study and in others, the number of children per indigenous woman was high, and the first delivery happened at an early age, thus resulting in many years of breastfeeding. 3,21,27,30 Parity is inversely associated with mammographic density, 31 and thus represents a protective factor against breast cancer. 32 It seems that the state of involution depends, in part, on parity: after successive pregnancies, stem cells and/or progenitor cells would accumulate in the mammary glands, and this has been observed in multiparous female mice.…”

“…1,2 Women of indigenous origin clearly present lower incidences of breast cancer than women with no indigenous descent. [3][4][5][6] The incidence of breast cancer in the indigenous population in Brazil is very low, and absolutely no cases have been found in some ethnic groups, such as the Xavantes group, living in the state of Mato Grosso. 7 This phenomenon can be explained by lifestyle habits: some peculiarities of indigenous populations are indeed protective factors, e.g.…”

“…7 However, indigenous populations also present some risk factors for breast cancer: sedentary lifestyle, overweight and obesity are observed in more than half of these women. 3 Breast density, as evaluated by mammography (mammographic density), is an independent risk factor for breast cancer, which is independent of age, menopausal status or exogenous steroid use. [8][9][10][11][12] To our knowledge, there is no other study in the literature addressing the relationship between demographic and clinical factors and mammographic density among indigenous women in Brazil.…”