Best friend’s and family members’ smoking habits and parental divorce during childhood are
associated with smoking in adulthood
Sammanfattning
AIMS – Smoking initiation during childhood or adolescence is strongly associated with friends’
smoking. Likewise, adverse living conditions increase the likelihood of future deviant behaviour.
We examine whether smoking by a best friend and family members during school years as well
as adverse childhood experiences are associated with smoking in adulthood. DATA AND DESIGN
– We have analysed the responses of Finnish working-aged respondents in 1998 (N=25901) and
2003 (N=20773) to questions on the smoking status of friends and family members during school
years as well as their answers on a six-item scale of childhood adversities. A case-control study
design was used to compare current cigarette smokers (1998 and 2003) to non-smokers (1998 and
2003). RESULTS – If a best friend during school years was a smoker, the subject’s odds ratio (OR) of
being a smoker in adulthood was 4.43 among females and 3.91 among males compared to those
with a non-smoking best friend in multivariate models adjusted for smoking by family members
during school years and by six childhood adversities. These associations did not differ by age.
Smoking in adulthood was associated with childhood adversities, most strongly with parental
divorce or separation during the subjects’ school years. CONCLUSION – Smoking by a best friend
and parental divorce or separation during school years appears to be a strong factor of smoking
in later life.