28 Scientific American, March 2020
THE SCIENCE
OF HEALTH
Claudia Wallis is an award-winning science journalist whose
work has appeared in the New York Times, Time, Fortune and the
New Republic. She was science editor at Time and managing editor
of Scientific American Mind.Illustration by Fatinha RamosAs a young attending physician at a Connecticut medical center
35 years ago, Sharon Inouye was shocked by the disturbing
changes she saw in many older patients. They would arrive at the
hospital clear-headed and focused but soon became confused
and disoriented—for no obvious or consistent reason. Some de -
veloped delusions and thrashing agitation; others seemed sedat-
ed and out of it. “I asked other physicians about it, and they were
dismissive,” she recalls. This muddled state known as delirium
“was taken as an expected thing” for older patients, but Inouye
found it to be both unacceptable and deeply interesting. Now a
geriatrician and professor at Harvard Medical School, she is one
of the world’s leading investigators of delirium, the toll it can
take and how to prevent it.
Delirium is astonishingly common. It affects between 10 and
50 percent of hospitalized patients aged 65 and older, whether
they have had surgery or not, and up to 85 percent of those in
intensive care units. It is the number-one complication of surgery
in this demographic. And yet until recently, delirium was rarely
mentioned to patients or their families. One reason that is chang-
ing is the dramatic rise in elderly surgical patients. “It’s only in
recent years that we started to see a large number of patients in
their 80s and 90s coming to surgery,” says Frederick Sieber, chair
of the department of anesthesiology and critical care medicine at
Johns Hopkins University School of Medicine.
Another reason delirium is finally getting attention is that
research by Inouye and others has shown that for many patients
the condition is associated with longer-term risks, including
loss of mental acuity. This is the phenomenon, sadly familiar to
many families, of Grandpa never being quite the same after an
operation. Whether delirium causes enduring harm to the brain
or merely exposes and perhaps accelerates preexisting cognitive
issues is not clear. Nor is it clear how anesthesia or surgery
might trigger the condition. Sieber, for example, has extensive-
ly studied whether using local rather than general anesthesia
and using mild versus heavy sedation make a difference. They
do not. What seems to be driving the risk, he says, are un -
derlying vulnerabilities that include chronic diseases and incip-
ient dementia.
The consequences of delirium, if it lasts more than a few days
and especially if it is followed by cognitive decline, are enor-
mous. “It’s a house of cards,” Inouye says. “Patients start getting
treated with medications for agitation or disruptive behavior,
and those medications lead to complications. Or they are very
sedated, and that leads to complications.” Delirious patients may
choke on their food or pills and die of aspiration pneumonia.
They may wind up in bed for long periods and suffer fatal blood
clots. Once up, they are prone to falling. It’s a downward spiral
and a costly one. Delirium adds more than $183 billion a year to
U.S. health care costs, outstripping congestive heart failure.
Fortunately, basic steps can be taken to prevent delirium or
shorten its course, such as making sure the patient is well
hydrated, has access to eyeglasses and hearing aids if he or she
uses them, gets out of bed and walks as soon as possible, has ade-
quate sleep, and is socially engaged by hospital staff and loved
ones. These are some of the measures included in the Hospital
Elder Life Program (HELP), first developed by Inouye and her
colleagues in 1993 and now in use in hundreds of hospitals
around the world. Studies show it reduces the risk of delirium by
30 to 50 percent, shortens its course when it does occur and cuts
the rate of falls by 42 percent. Notably it saves between $1,600
and $3,800 per patient in hospital costs and more than $16,000
in long-term care costs in the year following delirium.
This month AARP, via its affiliated Global Council on Brain
Health, is releasing a report on delirium aimed at helping people
reduce their risk and improve their outcome, particularly the 50
percent or so who will face surgery at some point after age 65,
says Sarah Lenz Lock, senior vice president of policy and brain
health at AARP. She wishes she had known more about it when
her own mother “wigged out” after an aortic repair. Lock says she
would have set up bedside shifts with family so that her mom was
never alone: “I would have made sure she went in hydrated and
been prepared that recovery might take a little longer.”Delirium: Taken
Seriously at Last
The most common complication
of surgery or hospitalization for
older patients can often be prevented
By Claudia Wallis
© 2020 Scientific American