Family caregivers help loved ones suffering from many illnesses, from heart disease to severe arthritis. But a new study shows that one condition—dementia—places an outsized burden on those family members. They spend more hours, do more difficult work, and provide assistance for more years than family members caring for older adults without memory loss.

An article in the journal Health Affairs reports that while people with dementia account for only about 10 percent of older adults living at home or in residential care, 41 percent of family caregiving hours are spent assisting loved ones with Alzheimer’s and similar diseases.

In 2011, about 3.6 million people with dementia lived in settings other than nursing homes. Three-quarters received assistance with self-care such as eating, bathing, or dressing; or with household activities. By contrast, only one-in-five older adults without dementia received this help.

The researchers, Judith Kasper and Jennifer Wolf at the John Hopkins Bloomberg School of Public Health, Vicki Freedman at the University of Michigan and my colleague Brenda Spillman at the Urban Institute, found that among those with dementia who received care, their level of assistance was often very intense. Two-thirds had help with self-care, and 40 percent received assistance with three or more of these activities. Among those without dementia, only about 14 percent got help with three or more daily activities.

Caregivers who lived with family members with dementia provided nearly 50 percent more hours of help than those who lived with an aging parent without dementia—an average of 143 hours per month (almost 36 hours per week, or nearly the equivalent of a full-time job). When the survey was done in 2011, nearly half of those helping family members with dementia had provided care for six years or more, while 29 percent assisted family members without dementia for that long.

The researchers found about 8 percent of those with dementia received no help at all—and about 40 percent of them lived alone. These were what the researchers called “a small, but potentially vulnerable subset of older community residents.”

Not surprisingly, 44 percent of people with dementia were 85 or older and nearly 20 percent were 90 or older. Nearly half were widows. Those with dementia were less likely to live alone than older adults without these diseases, and one-quarter lived with a son or daughter.

One indication of how difficult it is to care for a loved one with dementia: Nearly one-third had three or more caregivers and the same percentage had paid assistance. By contrast, only about 20 percent of older adults without dementia received paid care.

The research is based on two big national studies—the 2011 National Health and Aging Trends Study and the companion National Study of Caregiving.

One caveat: The study was based on surveys of caregivers rather than diaries or other contemporaneous  accounts, thus respondents may have misremembered the amount of time they spent helping family members.  And keep in mind that the diagnosis of dementia is uncertain. Often, people suffer from impaired memories but have never been formally diagnosed with dementia.

Still, this study shows just how difficult it is for family members to care for loved ones with dementia. Caring for a family member is never easy, but helping someone with dementia is especially challenging.

Sadly, while government spends an estimated $150 billion annually in Medicaid and Medicare dollars to care for those with dementia and about $570 million on drug research to cure or slow the onset of Alzheimer’s disease, it does little to support those family caregivers whose loved ones suffer from this and other dementias.

This Health Affairs study shows how desperately those caregivers need support and training. Yet, there is little outcry for this help. One group that advocates for more assistance for those with dementia and their family members is the Dementia Action Alliance (full disclosure: I am an unpaid adviser). I wish more organizations would speak up.