As married couples spend day in and day out together, they begin to experience a level of interdependence in which one spouse's quality of life is very closely tied to that of the other.
This interdependence persists even after the death of one spouse, according to new research from the University of Arizona.
A person's quality of life at the time of their death continues to influence his or her spouse's quality of life in the years following the person's passing, according to new research published in Psychological Science, a journal of the Association for Psychological Science.
What's more, the association between a deceased and surviving spouse is just as strong as the association between partners who are both living, the researchers found.
"If your partner has higher quality of life before they pass away, you're more likely to have higher quality of life even after they're gone," said Kyle Bourassa, a UA psychology doctoral student and lead author of the paper. "If he or she has lower quality of life before they pass away, you're then more likely to have lower quality of life."
In previous work, Bourassa and his colleagues found evidence that a person’s cognitive functioning and health influence not only his or her own well-being but also the well-being of his or her partner. They wondered whether this interdependence continues when one of the partners passes away.
To find out, they turned to the multinational, representative Study of Health, Aging and Retirement in Europe, or SHARE, an ongoing research project with more than 80,000 aging adult participants across 18 European countries and Israel.
Specifically, they examined data from 546 couples in which one partner had died during the study period and data from 2,566 couples in which both partners were still living.
The researchers were surprised to find no observable difference in the strength of the interdependence in couples' quality of life when comparing widowed spouses with spouses whose partners remained alive. They replicated these findings in two independent samples from the SHARE study, while controlling for other factors that might have played a role, such as participants' health, age and number of years married.
"Even though your marriage ends in a literal sense when you lose your spouse, the effects of who the person was still seems to matter even after they're gone," Bourassa said. "I think that really says something about how important those relationships are."
While it's not entirely clear why the interdependence persists, it's likely that the thoughts and emotions a person experiences when reminiscing about a lost spouse may contribute to the ongoing connection, the researchers say.
"Relationships are something we develop over time and they are retained in our mind and memory and understanding of the world, and that continues even after physical separation," said Mary-Frances O'Connor, UA assistant professor of psychology and a co-author of the paper who specializes in grief and the grieving process.
Bourassa said the findings could have implications for end-of-life care and for helping those who have lost their spouses. "If you can boost someone's quality of life before they pass, that might affect not just their life, but the quality of life of their partner and their family."
Other authors on the paper were David Sbarra, UA associate professor of psychology, and Lindsey M. Knowles, UA psychology doctoral student.