William F. Forbes

The importance of social relationships, socioeconomic status and health practices with respect to mortality among healthy Ontario males

The associations of social relationships, socioeconomic status and health practices with 20-year mortality were examined in a cohort of 2000 Ontario males. A social relationships index comprised of marital status, number of children, family contact and participation in voluntary associations had a strong association with mortality (adjusted relative risk of 0.30, 95% CI 0.11-0.83, comparing the highest 10% with the lowest 10% scores of the index). Among indicators of socioeconomic status, only income was significantly related to mortality with an adjusted relative risk of 0.41 (95% CI 0.23-0.72) for the highest 20% compared with the lowest 20% income group. The adjusted relative risk for smokers compared with non-smokers was 2.26 (95% CI 1.51-3.37). The joint effects of a relatively high score in the social relationships index, high income and being a non-smoker is estimated to represent an approximately 18-fold reduction in the risk of mortality during the follow-up period.

The role of carbon monoxide in cigarette smoking. I. Carbon monoxide yield from cigarettes.

The carbon monoxide deliveries of 20 major Canadian brands of cigarettes, determined by gas chromatography and using standard smoking conditions, were estimated and found to vary by a factor of about two. The CO yields were found to increase with puff volume and tobacco moisture, decrease with increased paper porosity, but remain essentially constant with puff duration. The data suggest that reduced CO deliveries can be achieved by increasing the cigarette paper porosity. Combustion temperature presumably also influences CO deliveries, but the relative role ascribed to dilution and combustion is not clear. It may be concluded that smokers can lower their CO exposure by reducing their puff volume, smoking cigarettes manufactured from high porosity paper, by taking fewer puffs, and decreasing their tendency to inhale. Since CO and tar deliveries are correlated, these measures would also tend to decrease a smokers exposure to tar.

Institutionalization of the elderly in Canada

The organization of institutional long-term care a demographic profile of the institutionalized elderly the community-institution interface health status and therapeutic programs institutionalizations - sources of concern future directions for policy and research.

Risk factors, causality, and policy initiatives: the case of aluminum and mental impairment.

The question addressed is when can the evidence concerning a health issue be regarded as adequate to implement policy initiatives. The approach is illustrated by comparing evidence about the effects of cigarette smoking with evidence for the aluminum (Al) hypothesis (that Al contributes to mental impairment and especially to Alzheimers Disease). The criteria for evaluating the evidence are based on the consistency and strength of the association between a putative risk factor and the relevant outcome variable, the likelihood that the relative risk represents a causal relationship, whether possible mechanisms are available, the number of persons affected, and the costs of modifying the risk factor.

Estimates of the Relative Risk of Mortality Based on the Ontario Longitudinal Study of Aging

Data from the Ontario Longitudinal Study of Aging were analyzed to examine the associations of the independent variables income, income change, education, smoking and perceived health with the dependent variable mortality during a ten year follow-up beginning in 1969. The analyses investigate the associations of the independent variables with deaths, with other causes of attrition and with all causes of attrition. The results indicate that smoking is the strongest predictor of mortality, and income is the strongest socioeconomic predictor. The analyses also show that perceived health measured prior to the mortality follow-up masks the association between the independent variables and mortality. Since the exclusion of the perceived health variable did not appreciably reduce the fit of the models, it was omitted from further analyses. The distributions of mortality for the various independent variables differed appreciably between models using deaths and all causes, but the bivariate and multivariate associations between variables were relatively unaffected by the alternative methods of operationalizing the dependent variable.

The Relationship Between Aging and Disease: Geriatric Ideology and Myths of Senility

An ongoing debate in gerontology concerns the relationship between aging and disease. Goodwin, as part of a discussion on the importance of geriatric ideology, argues that age‐related disorders like senile dementia of the Alzheimers type (SDAT) should be regarded as an aging process, while others suggest it is more appropriate to consider it as a disease. This paper comments on the arguments presented by Goodwin and develops these by providing a review of the underlying assumptions concerning aging and disease. The policy relevance and implications for future research are also outlined.

Changes in collagen with age. II. Modification of collagen structure by exposure to the gaseous phase of tobacco smoke.

Abstract The changes, which occur when soluble collagen is exposed to gaseous phase of tobacco smoke, are investigated by amino acid analyses, chromatography and electrophoresis. It is shown that a dose-dependent loss of lysine occurs, together with loss of solubility, and the formation of a new compound with co-chromatographs with α, ϵ-diaminopimelic acid. Similar exposure of trypsin indicates that the action of tobacco smoke on this compound also causes similar changes, together with a loss of enzymatic activity. These results are compared with the changes that occur in collagen as a function of age.

The Free Radical Theory of Aging: A Critique and Unresolved Questions

The free radical theory of aging is critically discussed. This review deals with the biological effects of free radicals during the aging process, the relationship between aging and diseases and how they both may be affected by free radicals, and the effects of free radicals on the human lifespan. The paper emphasizes aspects which require additional investigation.

The effect of prednisolone phosphate on the life-span of DBA/2J mice

Abstract Ninety-eight female DBA/2J mice were separated into two groups, and to one group prednisolone sodium phosphate was administered orally via the drinking water at a concentration between 3·0 and 3·2 μg/ml. The treatment was started when the animals were 232-days-old. No significant differences could be observed in the mortality curves for the control and experimental animals. The mean life-span of the mice was about 785 days, somewhat greater than the previously reported life-span for DBA/2J mice of 714 days.

Effects of screening errors and differential mortality on the estimation of the incidence of dementia in the Canadian Study of Health and Aging.

The Canadian Study of Health and Aging produced an estimate of the incidence of dementia among elderly Canadians by following up, after 5 years, the undemented found in an initial prevalence survey. Initial and follow-up estimates could be biased by false-negative error in the screening tool used for subjects living in the community, and by erroneous classification of subjects who died in the interim. Here, we use a deterministic model to quantify those possible biases. We conclude that, using the estimates of the errors from control samples, the incidence among community subjects would be overestimated by 15%, and the incidence among the institutional subjects would be underestimated by 37%. The overall incidence would be underestimated by 14%. Most of the bias can be attributed to inaccuracies in the classification of deaths.