The cost of Alzheimer’s disease is immeasurable for those who suffer its depredations, but a recent study showing it to be the most expensive malady in the United States should be a call to action.

The nonprofit RAND Corp. found this cruel disease costs American families and society $157 billion to $215 billion a year. The research was financed by the federal government.

These are enormous numbers that are only growing larger as the cost of care increases. Funding spent on stemming the disease would not be wasted and should be among the top priorities, along with bigger killers – cancer research and heart disease.

Given the aging demographics of baby boomers and the lack of young people to care for them as they age, this new study is startling. The study offers what experts say is the most reliable estimate for the number of Americans who have dementia at around 4.1 million. That is less than the widely cited 5.2 million estimate from the Alzheimer’s Association but, as one official there observed, the bottom line is the same. Dementia is among the most costly diseases to society.

By 2040, the number of Americans with dementia is expected to balloon to 9.1 million, according to the study. The financial impact that this disease already has on Medicare and Medicaid is massive, and it will only grow.

The direct costs of dementia are equally startling: $109 billion a year in 2010 dollars, according to the study, compared to $102 billion for heart disease and $77 billion for cancer.

Informal care is another matter and cannot be quantified. Hardships placed on the person suffering and on family members are endless. The study recognizes that the cost of informal care by family members and others pushes the cost of dementia even higher, depending on how the care and lost wages are valued.

Sponsored by the government’s National Institute on Aging and published in the New England Journal of Medicine, this is America’s wake-up call. Just as with cancer, the number of individual lives affected and collective impact cannot be ignored.

Sufferers of Alzheimer’s, the most common form of dementia and the sixth-leading cause of death in the United States, have been speaking out. Their efforts, along with the types of intensive study done by the RAND Corp., should move the agenda. Discussion on the cost of care and its impact on society ought to result in more funding dedicated to eradicating or, at least lessening, the effects of the disease. This is taxpayer money well spent.