A COHORT ANALYSIS OF THE SEX DIFFERENTIAL IN MORTALITY AMONG OLDER ADULTS: ENGLAND AND WALES

The transition from high to low levels of mortality in industrialized countries has been characterized by a persistent widening in the sex differential. Possible influences on the sex differential include both inherent biological differences between males and females, and environmental differences, for example, cigarette smoking. The effects of many of these factors are cumulative and persistent, and represent long term consequences of the behavior and experience of individuals at earlier points in their lives. This suggests that a cohort approach to the transition from high to low levels of mortality might provide new insight into the underlying causes of the longevity advantage enjoyed by females.

The analysis focusses on the experience of England and Wales. The data are based on mortality rates from the Registrar General's office, and on a variety of social, economic and demographic factors. The analysis is limited to mortality trends for the age groups 50-54 through 80-84.

The application of dummy variable regression examines the relative influence of ages, periods and cohorts on the sex differential for mortality for all causes and for specific cause of death categories. Multiple regression is employed to examine the explanatory power of a selected group of biological environmental and behavioral variables for which the sets of period and cohort dummy variables serve as proxies. Separate models are estimated for changes in mortality rates by sex and in the sex differential for all causes and for cardiovascular diseases, neoplasms and influenza, pneumonia and bronchitis. In each case, the dependent variables are regressed on a set of cohort-specific factors and on a combined set of cohort and period specific variables.

The results of the dummy variable regression provide some support that cohort-specific factors are of more importance than period-specific factors for the widening sex differential. In general, the multivariate cohort model suggest that tobacco consumption had a major positive impact on the sex differential, while changes in the real wage index were associated with reductions in all cases except for mortality for cardiovascular diseases.