[Smoking in households in Brazil with children younger than 5 years of age].

OBJECTIVES To estimate the prevalence of exposure to smoking in households with children younger than 5 years of age in the city of Cuiabá, Mato Grosso, Brazil, and to identify the main determinants of that exposure. METHODS This cross-sectional, population-based study included 2 037 families from the city of Cuiabá. The parents of the children or other caregivers answered a questionnaire concerning the smoking habits of people living in the household, sociodemographic characteristics of the household, and the household's living conditions. RESULTS The overall prevalence of smoking in the households was 37.7%. In terms of income, in the households with a monthly per capita income of 2 minimum wages or more, the prevalence of smoking was 24.1%; it was 31.3% in the households with a monthly per capita income between 1 and 1.9 minimum wages; and it was 46.0% in households with a monthly per capita income below 1 minimum wage. With respect to socioeconomic level (the family's material goods and purchasing power and the educational level of the head of the household, divided into five classes, from A (highest) to E (lowest)), the higher the socioeconomic level, the lower was the prevalence of smoking in the household: 26.9% for class A, 26.4% for class B, 34.9% for class C, 45.1% for class D, and 47.2% for class E. There was a higher prevalence of smoking when the father did not live in the home (47.5% versus 35.5%), when the head of the family was someone other than the father or the mother (53.8% versus 33.9% and 38.8%, respectively), when the father was younger than 20 years (52.3% versus 31.2% for fathers 40 or older), and when the mother was younger than 20 years (46.1% versus 22.5% for mothers 40 or older). In terms of occupation, the lowest prevalence of household smoking was found with health professionals and teachers, for both women (18.3%) and men (14.7%). After multivariate logistic regression analysis, the following variables remained associated with household smoking: absence of the father from the household, maternal and paternal schooling, maternal and paternal occupation, child's age, and household monthly per capita income. CONCLUSION The risk of exposure to household smoking (and thus to passive smoking) in this sample of children younger than 5 years of age was higher in households living in poorer socioeconomic conditions.