The stress of caring for a child with a disability may truly take a toll, with a new study suggesting that mothers of those with special needs see greater declines in memory as they age.

Mothers of those with disabilities are at increased risk of cognitive aging compared to those with only typically-developing children, according to the study published in the The Journals of Gerontology: Series B.

Fathers, however, did not see the same impact.

“These mothers often face more chronically stressful situations due to their children’s disabilities and need for care and support,” said Jieun Song, an associate researcher at the Waisman Center at the University of Wisconsin-Madison who led the study. “Chronic stress has been found in past research to lead to memory decline, especially among older women, as a result of both mental health problems and physical health problems.”

Researchers looked at data on 128 parents of those with childhood-onset disabilities and 512 parents of typically-developing kids who participated in a large, national survey. The moms and dads completed an interview, a mail-in survey and a battery of cognitive tests.

Effects on memory were most severe in moms who reported the greatest difficulty handling their children, the study found. However, having support from friends and feeling in control appeared to offer “protective effects” from cognitive decline.

Both mothers and fathers of children with disabilities had more negative parenting experiences than parents of typically-developing kids, but otherwise fathers in both groups fared similarly, the study found.

In contrast, moms of those with disabilities including autism, cerebral palsy, Down syndrome and intellectual disability were more than twice as likely to report experiencing depression within the past year as compared to other mothers. They also reported “significantly poorer” physical health even though women in both groups had similar levels of physical activity.

Fathers were likely spared from the cognitive impact because they tend to spend less time than mothers exposed to the stresses of childcare and housework, Song said. In addition, she added that research suggests that men are less vulnerable than women to the effects of stress on cognition.

“The findings indicate that keeping quality friendship, sense of control for life and (a) physically active lifestyle would help to protect these parents from accelerated cognitive aging,” Song said.