Couples' quality of life linked even when one partner dies

"The people we care about continue to influence our quality of life even when we they are gone," says lead researcher Kyle Bourassa, a psychology doctoral student at the University of Arizona. "We found that a person's quality of life is as interwoven with and dependent on their deceased spouse's earlier quality of life as it is with a person they may see every day."

In previous work, Bourassa and colleagues had found evidence of synchrony, or interdependence, between partners' quality of life, finding that a person's cognitive functioning or health influences not only their own well-being but also the well-being of their partner. Bourassa and colleagues wondered whether this interdependence continues even when one of the partners passes away.

To find out, the researchers turned to the multinational, representative Study of Health, Ageing, and Retirement in Europe (SHARE), an ongoing research project with over 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 2566 couples in which both partners were still living.

As one might expect, the researchers found that participants' quality of life earlier in the study predicted their quality of life later. And the data also provided evidence for interdependence between partners -- a participant's quality of life earlier in the study was associated with his or her partner's quality of life later.

Intriguingly, the results revealed interdependence between partners even when one partner died during the study; the association remained even after Bourassa and colleagues accounted for other factors that might have played a role, such as participants' health, age, and years married.

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. Importantly, the results from first group of couples were replicated in a second, independent sample of couples from the SHARE study, bolstering the researchers' confidence in the findings.

"Even though we lose the people we love, they remain with us, at least in part," explains Bourassa. "At some level, this accentuates how important relationships are for our well-being, but the findings cut two ways -- if a participant's quality of life was low prior to his or her death, then this could take a negative toll on the partner's later quality of life as well."

Although the study does not address the mechanisms underlying interdependence between partners, Bourassa and colleagues hypothesize that ongoing interactions are a likely driver of synchrony in intact couples, while the thoughts and emotions generated by reminiscing may explain interdependence for those who lost spouses.

The researchers hope to examine possible mechanisms in future experimental research:

"What we want to know is this: Is just thinking about your partner enough to create the interdependence?" says Bourassa. "If so, how might we use this information to better help those who have lost their spouse?"