People with happy spouses may live longer

"The data show that spousal life satisfaction was associated with mortality, regardless of individuals' socioeconomic and demographic characteristics, or their physical health status," says study author Olga Stavrova, a researcher at Tilburg University in the Netherlands.

Notably, spouses' life satisfaction was an even better predictor of participants' mortality than participants' own life satisfaction. Participants who had a happy partner at the beginning of the study were less likely to pass away over the next 8 years compared with participants who had less happy partners.

"The findings underscore the role of individuals' immediate social environment in their health outcomes. Most importantly, it has the potential to extend our understanding of what makes up individuals' 'social environment' by including the personality and well-being of individuals' close ones," says Stavrova.

Life satisfaction is known to be associated with behaviors that can affect health, including diet and exercise, and people who have a happy, active spouse, for example, are likely to have an active lifestyle themselves. The opposite is also likely to be true, says Stavrova:

"If your partner is depressed and wants to spend the evening eating chips in front of the TV -- that's how your evening will probably end up looking, as well."

Stavrova examined data from a nationally representative survey of about 4,400 couples in the United States who were over the age of 50. The survey, funded by the National Institute on Aging, collected data on participants who had spouses or live-in partners; 99% of the sampled couples were heterosexual.

For up to 8 years, participants and their spouses reported on life satisfaction and various factors hypothesized to be related to mortality, including perceived partner support and frequency of physical activity. They also completed a self-rated health measure and provided information related to their morbidity (as measured by number of doctor-diagnosed chronic conditions), gender, age at the beginning of the study, ethnicity, education, household income, and partner mortality. Participant deaths over the course of the study were tracked using the National Death Index from the Centers for Disease Control and Prevention or spouses' reports.

At the end of 8 years, about 16% of participants had died. Those who died tended to be older, male, less educated, less wealthy, less physically active, and in poorer health than those who were still alive; those who died also tended to report lower relationship satisfaction, lower life satisfaction, and having a partner who also reported lower life satisfaction. The spouses of participants who died were also more likely to pass away within the 8-year observation period than were spouses of participants who were still living.

The findings suggest that greater partner life satisfaction at the beginning of the study was associated with lower participant mortality risk. Specifically, the risk of mortality for participants with a happy spouse increased more slowly than mortality risk for participants with an unhappy spouse. The association between partner life satisfaction and mortality risk held even after accounting for major sociodemographic variables, self-rated health and morbidity, and partner mortality.

Exploring plausible explanations for these findings, Stavrova found that perceived partner support was not related to lower participant mortality. However, higher partner life satisfaction was related to more partner physical activity, which corresponded to higher participant physical activity, and lower participant mortality.

This research demonstrates that partner life satisfaction may have important consequences for health and longevity. Although the participants in this study were American, Stavrova believes the results are likely to apply to couples outside of the United States, as well.

"This research might have implications for questions such as what attributes we should pay attention to when selecting our spouse or partner and whether healthy lifestyle recommendations should target couples (or households) rather than individuals," says Stavrova.

Future research could also investigate larger social networks to see if the same pattern of results emerges in the context of other relationships.