Abstract
Objectives
Research on the association between income and smoking cessation has examined income as a static phenomenon, either cross-sectionally or as a predictor variable in longitudinal studies. This study recognizes income as a dynamic entity and examines the relationship between a change in income and subsequent smoking behaviour.
Method
Longitudinal data from the National Population Health Survey (1994/5 to 2008/9) were used to examine the impact of 1) change in income and 2) change in poverty status, on the probability of being a former or current smoker among a sample of Canadians identified as having ever smoked. Covariates include socio-demographic characteristics, number of cigarettes smoked per day, and smoking in the home.
Results
Smoking behaviour was not associated with a change in household income but was associated with a change in household income that moved an individual across the poverty threshold. Canadians whose income increased to above the poverty threshold were less likely to continue smoking than someone who remained in poverty (OR=0.72, 95% CI: 0.62-0.84). Those who remained out of poverty were also less likely to continue smoking than someone who remained in poverty (OR=0.66, 95% CI: 0.57-0.75). There was no significant difference between those who remained in poverty and those whose income decreased to below the poverty level.
Conclusion
This study strengthens the link between smoking and poverty and supports strategies that address income as a socio-economic determinant of health. Policies that increase household incomes above the poverty line may lead to improvements in smoking cessation rates.
Key words: Income, longitudinal studies, low-income populations, poverty, smoking, smoking cessation
Résumé
Objectifs
Les études sur l’association entre le revenu et l’arrêt du tabac voient le revenu comme un phénomène statique, soit transversalement, soit comme une variable prédictive dans des études longitudinales. Notre étude reconnaît que le revenu est une entité dynamique et examine la relation entre un changement du revenu et l’usage subséquent du tabac.
Méthode
Les données longitudinales de l’Enquête nationale sur la santé de la population (1994-1995 à 2008-2009) ont servi à examiner l’effet: 1) d’un changement du revenu et 2) d’un changement du niveau de pauvreté sur la probabilité d’être un ancien fumeur ou un fumeur actuel au sein d’un échantillon de Canadiens et de Canadiennes désignés comme ayant déjà fumé. Nos covariables étaient le profil sociodémographique, le nombre de cigarettes fumées par jour et le tabagisme à la maison.
Résultats
L’usage du tabac n’était pas associé à un changement du revenu du ménage, sauf lorsque ce changement faisait franchir le seuil de la pauvreté à une personne. Les Canadiens et les Canadiennes dont le revenu avait suffisamment augmenté pour les hisser au-dessus du seuil de pauvreté étaient moins susceptibles de continuer à fumer que les personnes restées pauvres (RC=0,72, IC de 95 %: 0,62-0,84). Les personnes restées au-dessus du seuil de pauvreté étaient, elles aussi, moins susceptibles de continuer à fumer que celles restées pauvres (RC=0,66, IC de 95 %: 0,57-0,75). Il n’y avait pas d’écart significatif entre les personnes restées pauvres et celles dont le revenu était passé sous le seuil de pauvreté.
Conclusion
Notre étude renforce la preuve de l’existence d’un lien entre le tabagisme et la pauvreté et appuie les stratégies qui abordent le revenu en tant que déterminant socioéconomique de la santé. Les politiques qui font passer le revenu des ménages au-dessus du seuil de pauvreté pourraient améliorer les taux d’arrêt du tabac.
Mots clés: revenu, études longitudinales, populations à faible revenu, pauvreté, tabagisme, arrêt du tabac
Footnotes
Conflict of Interest: None to declare.
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