Tobacco retail availability and risk of relapse among smokers who make a quit attempt: a population-based cohort study.
INTRODUCTION
The availability of tobacco is thought to influence smoking behaviour, but there are few longitudinal studies examining if the location and number of tobacco outlets has a prospective impact on smoking cessation.


METHODS
The Ontario Tobacco Survey, a population-representative sample of Ontario adult smokers who were followed every 6 months for up to 3 years, was linked with tobacco outlet location data from the Ontario Ministry of Health. Proximity (distance), threshold (at least one outlet within 500 m) and density (number of outlets within 500 m) with respect to a smokers' home were calculated among urban and suburban current smokers (n=2414). Quit attempts and risk of relapse were assessed using logistic regression and survival analysis, adjusted for neighbourhood effects and individual characteristics.


RESULTS
Increased density of tobacco outlets was associated with decreased odds of making a quit attempt (OR: 0.54; 95% CI 0.35 to 0.85) in high-income neighbourhoods, but not in lower income ones. There was an increased risk of relapse among those who had at least one store within 500 m (HR: 1.41 (95% CI 1.06 to 1.88). Otherwise, there was no association of proximity with quit attempts or relapse.


CONCLUSIONS
The existence of a tobacco retail outlet within walking distance from home was associated with difficulty in succeeding in a quit attempt, while the increased density of stores was associated with decreased attempts in higher income neighbourhoods. The availability of tobacco may influence tobacco use through multiple mechanisms.
['Chaiton|Michael O|MO|0000-0002-9589-2122', 'Mecredy|Graham|G|', 'Cohen|Joanna|J|']
D000293:Adolescent D000328:Adult D000368:Aged D003132:Commerce D005260:Female D062306:Geography, Medical D006801:Humans D007182:Income D008297:Male D008875:Middle Aged D012008:Recurrence D012307:Risk Factors D012907:Smoking D062789:Tobacco Products D055815:Young Adult
Cessation Public policy Tobacco industry