Looking at married couples who were together less than 20 years and couples together for more than 50, Mejia and her colleagues have found striking similarities between partners who have spent decades together, especially in kidney function, total cholesterol levels and the strength of their grips, which is a key predictor of mortality. They presented their findings at the annual meeting of the Gerontological Society of America.
The data came from 1,568 older married couples across the United States. The couples were part of a larger dataset that included information on their income and wealth, employment, family connections and health, including information based on blood tests.
One obvious reason for partner similarity is that people often choose partners who are like them ”” people from the same stock, with similar backgrounds. But that didn’t explain why there were more similarities between the long-time partners, compared to the others.