Aug 20, 2014 07:16 AM EDT By Staff Reporter, UniversityHerald Reporter

Daughters spend twice as much time providing care to elderly parents than sons do, according to a Princeton University study. The researchers said that daughters provide an average of 12.3 hours of elderly parent care per month as compared to sons' 5.6 hours.

For the study, the researchers analysed data from the 2004 University of Michigan Health and Retirement Study that surveys over 26,000 Americans, aged 50 years and above, every two years.

"Whereas the amount of elderly parent care daughters provide is associated with constraints they face, such as employment or childcare, sons' caregiving is associated only with the presence or absence of other helpers, such as sisters or a parent's spouse," said study author Angelina Grigoryeva, a doctoral candidate in sociology, in a press release.  

"Sons reduce their relative caregiving efforts when they have a sister, while daughters increase theirs when they have a brother," Grigoryeva said. "This suggests that sons pass on parent caregiving responsibilities to their sisters."

The researchers said that there are significant negative mental and physical health consequences of elder care for caregivers. The consequences include higher mortality rate, career sacrifices, lower earnings and financial crunch. Often, caregivers have to balance elder care with employment.

Previous studies showed that women suffer from higher negative consequences associated with caregiving than men.

Grigoryeva said that although the U.S. has transformed into a gender egalitarian society since the 1970s, gender inequality exists, especially in elderly parent care.

A recent study by RAND Corp., a non-profit research organization, found that currently more than one million Americans are providing care for injured and disabled veterans since the terrorist attacks in 2001. In doing so, they are putting their own well-being at risk.

The researchers said that there are few public or private programs that support the needs of these aid military caregivers.

"Caring for a loved one is a demanding and difficult task, often doubly so for caregivers who juggle these activities with caring for a family and the demands of a job," study co-leader Rajeev Ramchand, a senior behavioral scientist, said in a press release. "These caregivers pay a price for their devotion."

Terri Tanielian, the study's co-leader and a senior social research analyst, said that until now the needs of this group have been poorly understood.

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