Health Effects of Cigarette Smoking: Data from the Ontario Longitudinal Study on Aging

The association between cigarette smoking and mortality is well established, but a similar association between cigarette smoking and morbidity is less well documented. We describe an analysis of data obtained from the Ontario Longitudinal Study of Aging which represents a cohort of about 2,000 males of similar age, which have been followed over a 20 year period since 1959. These data were analysed to investigate the effect of cigarette smoking on morbidity. Smokers were more likely to report poorer health; the estimated relative risks of being in poor health ranged from 1.29 to 1.61. In a longitudinal analysis, the relative risk of a transfer to the poor health group was estimated to be 1.30 for smokers compared with non-smokers, when the data were controlled for income and education. Income and education, when controlled for the other variable and for smoking status, were also found to be significant. When reported permanent disability is considered, smokers more frequently reported permanent disability, but the results were not significant at the 0.05 level. This smaller difference in reported permanent disability between the two groups may be caused by the greater drop-out rate for smokers compared with non-smokers, which would be expected to make the remaining smokers and non-smokers more similar with respect to their health status. In fact, drop-outs for all reasons, because of death and because of a lack of interest were significantly greater for smokers than for non-smokers. As a result of this consideration, the above-mentioned relative risks, related to smoking, should be regarded as minimal values. L'association entre la consommation de cigarettes et la mortalité est bien établie, mais celle avec la morbidité n'est pas aussi bien documentée. Cet article décrit une analyse des données provenant de l'Étude Longitudinale Ontarienne sur la Vieillissement, qui représente une cohorte d'environ 2.000 hommes d'âge analogue suivis pendant une période de 20 ans, depuis 1959. Ces données furent analysées pour examiner en détail l'effet des cigarettes sur la morbidité. Les résultats montrent que les fumeurs sont plus souvent en mauvaise santé; l'estimation des risques relatifs de mauvaise santé étaient classés de 1.29 à 1.61. Dans une analyse longitudinale, le risque relatif d'être transféré à un groupe de personnes en mauvaise santé, était estimé de 1.30 pour les fumeurs en comparaison avec les non-fumeurs, quand les données étaient contrôlés du point de vu