I use hazard regression methods to examine how the age difference between spouses affects their survival. In many countries, the age difference between spouses at marriage has remained relatively stable for several decades. In Denmark, men are, on average, about three years older than the women they marry. Previous studies of the age gap between spouses with respect to mortality found that having a younger spouse is beneficial, while having an older spouse is detrimental for one’s own survival.
Most of the observed effects could not be explained satisfactorily until now, mainly because of methodological drawbacks and insufficiency of the data. The most common explanations refer to selection effects, caregiving in later life, and some positive psychological and sociological effects of having a younger spouse. The present study extends earlier
work by using longitudinal Danish register data that include the entire history of key demographic events of the whole population from 1990 onward. Controlling for confounding factors such as education and wealth, results suggest that having a younger spouse is beneficial for men but detrimental for women, while having an older spouse is detrimental for both sexes.
In recent years, the search for a single determinant of lifespan, such as a single gene or the decline of a key body system, has been superseded by a new view (Weinert and Timiras 2003). Lifespan is now seen as an outcome of complex processes with causes and consequences in all areas of life, in which different factors affect the individual lifespan simultaneously.
Today’s standard of knowledge is that about 25% of the variation of the human lifespan can be attributed to genetic factors and about 75% can be attributed to nongenetic factors (Herskind et al. 1996). Research focusing on nongenetic determinants of lifespan has suggested that socioeconomic status, education, and smoking and drinking behavior have a major impact on individual survival
(e.g., Christensen and Vaupel 1996). Mortality of individuals is also affected by characteristics of their partnerships. Partnership, as a basic principle of human society, represents one of the closest relationships individuals experience during their lifetimes.
Regarding predictors of their mortality, partners usually share many characteristics, such as household size, financial situation, number of children, and quality of the relationship, but several factors might affect partners differently—for example, education and social status. A factor that might influence partners in different ways is the age gap between them.
