Researchers here make an attempt to extract some insight into causation from longitudinal data on retirement age and subsequent mortality rates. If continuing to work on balance involves undertaking more physical activity than would otherwise be the case, it isn't unreasonable to think that this might be a possible mechanism of causation, given the existing evidence for even low levels of activity such as that involved in cleaning and gardening to make a measurable difference to health and life expectancy in later life. Still, the data in this study isn't particularly compelling in and of itself; it has to be considered in the context of other research.
Researchers examined data collected from 1992 through 2010 through the Health and Retirement Study, a long-term study of U.S. adults. Of the more than 12,000 initial participants in the study, the focus narrowed to 2,956 people who began the study in 1992 and had retired by the end of the study period in 2010. "Most research in this area has focused on the economic impacts of delaying retirement. I thought it might be good to look at the health impacts. People in the U.S. have more flexibility about when they retire compared to other countries, so it made sense to look at data from the U.S."
Poor health is one reason people retire early and also can lead to earlier death, so researchers wanted to find a way to mitigate a potential bias in that regard. To do so, they divided the group into unhealthy retirees, or those who indicated that health was a factor in their decision to retire - and healthy retirees, who indicated health was not a factor. About two-thirds of the group fell into the healthy category, while a third were in the unhealthy category. During the study period, about 12 percent of the healthy and 25.6 percent of the unhealthy retirees died. Healthy retirees who worked a year longer had an 11 percent lower risk of mortality, while unhealthy retirees who worked a year longer had a 9 percent lower mortality risk. Working a year longer had a positive impact on the study participants' mortality rate regardless of their health status.
"The healthy group is generally more advantaged in terms of education, wealth, health behaviors and lifestyle, but taking all of those issues into account, the pattern still remained. The findings seem to indicate that people who remain active and engaged gain a benefit from that. Additional research is needed to better understand the links between work and health, the researchers said. As people get older their physical health and cognitive function are likely to decline, which could affect both their ability to work and their longevity. "This is just the tip of the iceberg. We see the relationship between work and longevity, but we don't know everything about people's lives, health and well-being after retirement that could be influencing their longevity."