The most rigorous study to date of how much it costs to care for Americans with dementia found that the financial burden is at least as high as that for either heart disease or cancer, and is probably higher. And both the costs and the number of people with dementia will more than double in 25 years, skyrocketing at a rate that rarely, if ever, occurs with a chronic disease.
The research, led by an economist at the Rand Corp., financed by the federal government, and published Wednesday in the New England Journal of Medicine, provides the most reliable basis yet for measuring the scale of this devastating problem. Until now, the most-cited estimates of the cost and prevalence of the condition came from an advocacy group, the Alzheimer's Association.
Although some of the figures from the new research are lower than the association's projections, they are nonetheless staggering and carry new gravity because they come from a dispassionate, academic research effort. Behind the numbers is the striking sense that the country, facing the aging of the baby boomer generation, is unprepared for the coming surge in the cost and cases of dementia.
"It's going to swamp the system," said Dr. Ronald C. Petersen, who is chairman of the advisory panel to the federal government's recently created National Alzheimer's Plan and was not involved in the Rand study.
In fact, Petersen, who as director of the Alzheimer's Disease Research Center at the Mayo Clinic is part of another team collecting data on dementia costs, said of the Rand numbers, "I think they're kind of lowballing things; they're being somewhat conservative."
The results show that dementia currently afflicts nearly 15 percent of people ages 71 or older, about 3.8 million people. By 2040, the authors said, that number will balloon to 9.1 million people.
"I don't know of any other disease predicting such a huge increase," said Dr. Richard J. Hodes, director of the National Institute on Aging, which financed the study. "And as we have the baby boomer group maturing, there are going to be more older people with fewer children to be informal caregivers for them, which is going to intensify the problem even more."
The study found that direct health care expenses for dementia, including nursing home care, were $109 billion in 2010. For heart disease, those costs totaled $102 billion; for cancer, $77 billion.
Beyond that, the study quantified the value of the sizable amount of informal care for dementia, usually provided by family members at home. That number ranged from $50 billion to $106 billion, depending on whether economists valued it by the income the family member was giving up or by what the family would have paid for a professional caregiver.
Michael D. Hurd, the lead author and a principal senior researcher at Rand, said the team could find no research quantifying such informal care for heart disease and cancer. But he and other experts agree that given the intensive nature and constant monitoring required to care for people with dementia, informal costs are probably much higher than those for most other diseases.
Each case of dementia costs $41,000 to $56,000 a year, the study said. Researchers project that the total costs of dementia care will more than double by 2040, to a range of $379 billion to $511 billion, from $159 billion to $215 billion in 2010.
Because the population will also increase, Hurd said, the burden of cost per American will not grow quite as fast, but will still be nearly 80 percent more in 2040.
The study used information collected during almost a decade on nearly 11,000 people from a large database called the Health and Retirement Study, considered a gold standard among researchers on aging issues. All of the people followed were given detailed cognitive tests, while a subset of them were even more intensely evaluated for dementia and their results used as benchmarks to rate cognitive decline for the others, Hurd said.
Hurd noted that in addition to the estimates of people with actual dementia, earlier analyses of the same data estimated that 22 percent of people ages 71 and older about 5.4 million people have mild cognitive impairment that does not reach the threshold for dementia. In the study, about 12 percent of those people developed dementia each year.
The number of dementia cases calculated in the Rand study is smaller than those from the Alzheimer's Association, which used a different database and tended to count people in earlier stages of memory loss. The association estimates that 5 million people ages 65 and older have Alzheimer's, the most common dementia.
The Rand cost estimates for current dementia care are similar to the Alzheimer's Association's, but the association's future cost projections are significantly higher: $1.2 trillion in 2050.
Robert Egge, the association's vice president for public policy, said his group's cost projections are based on the assumption that "more and more people will be in severe stages of dementia" in the future because they will be older.
Petersen, whose team at the Mayo Clinic will be analyzing costs using a third distinct data set, said he suspected that "the reality is somewhere in the middle" of the Rand numbers and the Alzheimer's Association's projections.