The increasing mortality advantage of the married
Marital status is increasingly important for life expectancy. Our research investigates the reasons for this change.
It has been known for many years that there are large differences in health and life expectancy between marital status groups. In two new studies published in Demographic Research and Population and Development Review, the authors show that these differences have increased sharply over the last decades in Norway, as they have also done in some other countries. Most importantly, life expectancy among never-married in Norway did not increase during the 1980s, and then increased only rather modestly, while the married experienced a strong increase throughout these decades.
- In 2008, at the end of the study period, mortality among never-married women and men was as high as that of the married three decades earlier - in other words they are lagging 30 years behind, explains Øystein Kravdal, one of the Principal Investigators at the Centre for Fertility and Health
- However, very little is known about the reasons for this increasing excess mortality of the non-married, which has occurred in spite of a growing number of cohabitants in these groups, says Kravdal.
The role played by education
Education is a key determinant of mortality, and other studies have suggested that the association between marriage and education has become less negative or more positive. The authors therefore investigate whether changes in educational composition of marital status groups can account for the increasing mortality disadvantage of the non-married. Using register data for the entire population, they demonstrate that educational patterns indeed have changed markedly, but this explains only up to 5% of the widening mortality gap between the never-married and the married.
Among the subgroup of the never-married who have low education, life expectancy has actually decreased over several years. In 2008, the remaining life expectancy at age 50 among never-married men with only primary education was 10 years shorter than among married men who had some university education and whose spouses also were at this educational level.
So, if changes in educational patterns are not the reason for the growing morality advantage of the married, what could the causes be?
- We can only speculate until we have more evidence, says Kravdal. We have several questions that we want to explore in our future research. Is it more difficult nowadays to manage life alone because people generally care less about others? Or have increasingly complex health care systems made it more difficult to navigate through them without support from a spouse? Or has a general underuse of health care among the non-married become more of a disadvantage because the treatment that is offered is better? Or are there increasing economic benefits from marriage or larger health advantages from these benefits?
The observed relationships between marital status and mortality are not only a result of causal effects of marital status on mortality; they also reflect that certain factors of importance for mortality affect the chance of marrying and remaining married? Have there been changes in this so-called selection? Is it, for example, possible that good health is seen as a more important requirement for marriage these days? We expect that our future research will give us some answers to these questions.
Kravdal, Ø. (2017). Large and growing social inequality in mortality in Norway: The combined importance of marital status and own and spouse's education. Population and Development Review. 2017, 43, 645-665.
Kravdal, Ø., E. Grundy and K. Keenan (2018). The increasing mortality advantage of the married: The role played by education. Demographic Research. 2018, vol 38, p471-512.
The Centre for Fertility and Health is a Centre of Excellence (SFF) at the Norwegian Institute of Public Health.