environmental tobacco smoke and the risk of coronary heart disease

background: passive or environmental smoking is one of the important health problems, to which many adults and children are exposed in involuntary status. methods: in this hospital based case-control study, household exposure to tobacco smoke as an estimate of passive smokers was conducted in hamadan, western iran. the purpose was to find the relationship between environmental smoking and incidence of coronary heart disease (chd). we interviewed 69 patients with chd and 69 without it as control group. the confounded factors (hypertension, hypercholestrolemia, diabetic mellitus, type a personality, and familial history) were removed as exclusion criteria while suppliers of oral contraceptives, physical activity, martial status and age (â±3) were matched. results: the findings showed that 54% of patients and 48% of the controls were exposed to tobacco smoke. the odds ratio of incidence of chd was 1.26 and confidence interval (ci) as 0. 65-2. 46. conclusion: there was no significant relationship between passive smoking and chd. more study on large sample is needed to assess environmental smoking effect on chd.