Reduction of Secondhand Smoke Exposure Among Healthy Infants in Iran: Randomized Controlled Trial

Abstract

The objective of this study was to assess whether counseling both mothers and fathers reduces their infants' exposure to secondhand smoke (SHS). Participants were 130 nonsmoking children aged less than 1 year, exposed to their fathers' or mothers' smoking, and recruited from a health center in southern Tehran. Eligible families were randomly assigned to intervention or control group. Infant urine samples were collected, and parents were interviewed at baseline and at a 3-month follow-up in each of the 2 groups. Mothers of the intervention group were provided 3 counseling sessions, one of which was face to face and 2 of which were by telephone. Fathers were provided 3 counseling sessions by telephone. Parents were also given an educational pamphlet and a sticker depicting a smoke-free home. The control group received usual care. Changes in infant urinary cotinine levels, parental cigarette consumption in the presence of the child, and home- and car-smoking bans were assessed. The intervention was effective in reducing infant urinary cotinine levels (1-tailed p = .029). There was a greater decrease in the total daily cigarette consumption in the presence of the child in the intervention group compared with the control group, and the differences between the 2 groups were statistically significant (1-tailed p = .03). While the differences between home-smoking bans in the 2 groups were statistically significant (1-tailed p = .049), the differences between car-smoking bans did not reach significance. Counseling similar to that employed in other countries can reduce infant exposure to SHS, suggesting generalizability.