[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.