Tending to older loved ones who have bold personalities may be harmful to their caregivers' physical health, report Cornell researchers.

People who cared for individuals characterized as "easygoing" and "well-intentioned" reported better physical health than those who cared for headstrong and less agreeable people. No effects, however, were found regarding the caregivers' mental health.

The study of 312 pairs of caregivers and care receivers, which is one of the first to look at the influence of care-receiver personality on caregiver health, was published online Dec. 11 in the Journals of Gerontology, Series B: and Social Sciences.

Caregiver health was particularly low when those receiving care were both low in and highly extraverted—a combination called a "leader type," said senior author Corinna Loeckenhoff, assistant professor of human development in the College of . "That kind of personality may be very successful in a business setting, but it's not if you're receiving care," Loeckenhoff said.

The findings have implications for the millions of Americans who provide informal eldercare. In 2011, 16 percent of the U.S. population over age 15—and nearly 25 percent of those between 45 and 64 years of age—provided some eldercare, according to the .

"The care recipient's personality is just as important a factor for caregiver health as chronic pain and ," said lead author Catherine Riffin, a graduate student in the field of human development. "Clinical evaluations of caregiving settings should take this into account."

Provided by Cornell University