“This won’t go on for very long,” Sharon Hall said to herself when she invited her elderly mother, who’d suffered several small strokes, to live with her.

That was five years ago, just before Hall turned 65 and found herself crossing into older age.

In the intervening years, Hall’s husband was diagnosed with frontotemporal dementia and forced to retire. Neither he nor Hall’s mother, whose memory had deteriorated, could be left alone in the house. Hall had her hands full taking care of both of them, seven days a week.

As life spans lengthen, adult children like Hall in their 60s and 70s are increasingly caring for frail, older parents — something few people plan for.

“When we think of an adult child caring for a parent, what comes to mind is a woman in her late 40s or early 50s,” said Lynn Friss Feinberg, senior strategic policy adviser for AARP’s Public Policy Institute. “But it’s now common for people 20 years older than that to be caring for a parent in their 90s or older.”

A new analysis from the Center for Retirement Research at Boston College is the first to document how often this happens. It found that 10 percent of adults ages 60 to 69 whose parents are alive serve as caregivers, as do 12 percent of adults age 70 and older.

The analysis is based on data from 80,000 interviews (some people were interviewed multiple times) conducted from 1995 to 2010 for the Health and Retirement Study. About 17 percent of adult children care for their parents at some point in their lives, and the likelihood of doing so rises with age, it reports.

That’s because parents who’ve reached their 80s, 90s or higher are more likely to have chronic illnesses and related disabilities and to require assistance, said Alice Zulkarnain, co-author of the study.

The implications of later-life caregiving are considerable. Turning an elderly parent in bed, helping someone get into a car or waking up at night to provide assistance can be demanding on older bodies, which are more vulnerable and less able to recover from physical strain.

Emotional distress can aggravate this vulnerability. “If older caregivers have health problems themselves and become mentally or emotionally stressed, they’re at a higher risk of dying,” said Richard Schulz, a professor of psychiatry at the University of Pittsburgh, citing a study he published in the Journal of the American Medical Association.

Socially, older caregivers can be even more isolated than younger caregivers. “In your 60s and 70s, you may have recently retired and friends and family members are beginning to get sick or pass away,” said Donna Benton, research associate professor of gerontology and director of the Family Caregiver Support Center at the University of Southern California.

Caregiving at an older age can put hard-earned savings at risk with no possibility of replacing them by re-entering the workforce. Yvonne Kuo, a family care navigator at USC’s caregiver support center, has been helping an 81-year-old woman caring for her 100-year-old mom with vascular dementia in this situation.

“There’s no support from family, and she’s used up her savings getting some paid help. It’s very hard,” Kuo said.

Judy Last, 70, a mother of three adult children and grandmother of six youngsters, lives with her mother, Lillian, 93, in a mobile home park in Boise, Idaho. Last moved in three years ago, after her mother had a bout of double pneumonia, complicated by a difficult-to-treat bacterial infection that put her in the hospital for eight weeks.

“You don’t know if it’s going to be permanent at the time,” said Last, whose father died of dementia in January 2016 after moving to a memory care facility. “Mom had asked me several years before if I would be there when she needed help and I told her yes. But I didn’t really understand what I was getting into.”

Feinberg said this isn’t uncommon. “People in their 90s with a disability can live for years with adequate support.”

Last doesn’t find caregiving physically difficult even though she’s had two hip replacements and struggles with arthritis and angina.   Her mother has memory problems and chronic obstructive pulmonary disease, relies on oxygen, uses a walker, has lost most of her hearing, and has poor eyesight.

But things are hard, nonetheless. “I had plans for my retirement: I imagined volunteering and being able to travel as much as my bank account would allow,” Last said. “Instead, I don’t take time off and leave my mother. A big thing I deal with is the loss of my freedom.”

Hall, who’s turning 70 in September and who lives in Cumming, Ga., managed her mother’s and husband’s complex needs for years by establishing a strict routine. Monday and Friday they went to a dementia respite program from 10 a.m. to 3 p.m. On other days, Hall cooked, shopped, did laundry, helped them with personal tasks, made sure they were well occupied, provided companionship and drove them to medical appointments, as necessary.

“I did not expect this kind of life,” said Hall, who has had two knee replacements and a broken femur. “If someone had told me it would be years caring for my mother and your husband is going to get dementia, I would have said ‘No, just no.’ But you do what you have to do.”

A few weeks after our conversation, Hall’s mother entered hospice following a diagnosis of aspiration pneumonia and life-threatening swallowing difficulties. Hall said she has welcomed the help of hospice nurses and aides, who ask her at each visit, “Is there anything else you need from us that would make it easier for you?”

Though older caregivers get scant attention, resources are available. Over the years, Hall has shared caregiving ups and downs at CareGiving.com — a significant source of information and comfort. Across the country, local chapters of Area Agencies on Aging run caregiver support programs, as do organizations such as the Caregiver Action Network, the Family Caregiver Alliance, the National Alliance for Caregiving and Parenting Our Parents, an outfit focused on adult children who become caregivers. A helpful list of resources is available here.

Sometimes, caring for a parent can be a decades-long endeavor. In Morehead City, N.C., Elizabeth “Lark” Fiore, 67, became the primary caregiver for her parents when they moved around the corner from her, in a mobile home park, in 1999. “My dad took me for a walk one day and asked if I could look after them as they got older and I said yes. I’m the oldest child and the oldest assumes responsibility,” she said.

For years her father — a difficult man, by Fiore’s account — had heart problems; her mother had a nervous breakdown and a slow, extended recovery. “They wanted me to be in their lives and I wanted to do for them — I’m a Christian — but it was killing me. My heart was in the right place but emotionally, I was a wreck,” Fiore said.

After her father’s death from kidney cancer in 2010, her mother became even more needy and Fiore found herself spending more time responding to calls for assistance — often about suspected medical emergencies. “My mom had a way of acting as if something was horribly wrong and then it turned out it wasn’t,” she explained.

Fiore’s health isn’t good: She says she has chronic fatigue syndrome and thyroid problems, among other issues. But she didn’t know how to ask for help and no one volunteered it, even when her husband, Robert, was diagnosed six years ago with dementia. “I always expected myself to handle everything,” she said.

Finally, the stress became unbearable last year and Fiore’s mother moved to a senior living community close to Fiore’s 62-year-old sister, 400 miles away. Now, Fiore spends more time attending to her husband’s needs and tries to support her sister as best she can.

“At 90, my mom is healthy as a horse, and I’m glad of that but it’s been a long time caring for her,” she said. “I’ve changed a lot as a result of caregiving: I’m more loving, more aware of people who are suffering. I’ve found out that I am willing to go the extra mile. But I have to admit what I feel is tired — just tired.”

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