Spousal concordance of smoking (results of seventeen-year observational study)

The purpose of the seventeenyear prospective cohort study was to explore the dynamics of smoking among men and women depending on the changes in the attitudes of a spouse to smoking. Doortodoor survey was performed randomly based on the list of apartments of Leninsky district residents in Tomsk (1546 residents including 427 married couples). The first stage of the study (from 1988 to 1991) aimed at elucidation of frequency of smoking among spouses. The observation period was 17 years. During the second stage of examination (from 2002 to 2005), 278 couples (456 individuals) from the previously observed family cohort were examined. An individual was considered to be a smoker if he/she had been smoking at least one cigarette daily for at least one year by the time of the study and if his/her experience of smoking cessation had been less than one year. The highest risk of smoking (RR=2.48; 95% CI 2.08-2.96) was found among men living with their wives who began to smoke during the study period; men whose wives were smoking during the first and the second examination had RR of 1.73 (95% CI 1.11-2.70) in comparison with men whose wives did not smoke. Women whose husbands were smoking during all stages of the survey had higher risk of smoking than women whose husbands never smoked (RR=5.12; 95% CI 1.22-21.39) or quitted smoking (RR=4.59; 95% CI 1.39-15.14). The frequency of smoking among individuals living with their spouses who stopped smoking and did not relapsed (13.1%) was significantly lower than among the spouses who relapsed after quitting smoking (31.6%; ƒ2=4.02; p=0.045) and those whose spouses started smoking during the observation period (66.7%; ƒ2=11.95; p=0.006).