Autoimmune diseases attack millions of people around the world, but no one is
quite sure how many people suffer or what these diseases take out of the world
For three years after Yvonne Norton gave birth to her second son, she had a
host of mysterious symptoms that left her family doctor baffled. Time and time
again, she sought his advice, to no avail. In desperation, she even visited a
psychiatrist who also had no answers, other than to say, "Whatever is wrong with
you, it isn't in your head."
Then, one day in 1975, she landed in a hospital with complete heart failure.
For three days she lay unconscious, coming around to learn that seven pints of
fluid had been drained from her lungs and that she was being treated with high
doses of cortisone. Six months later, the steroids were wreaking havoc on her
body, without improving her symptoms. "At one point, my son got into a fight at
school with a kid who called me a swollen monkey," she recalls. "I thought,
'this is serious'."
Norton, who lives near Wolverhampton in central England, then traveled down
to London for an appointment with a specialist at the Hammersmith Hospital.
After a month of inpatient care, she was discharged with her diagnosis written
on a piece of paper: systemic lupus erythematosus. "I carried it around for
weeks, until I finally managed to get my tongue around it," Norton recalls. She
quickly learned that her condition was an autoimmune disease in which the immune
system attacks the very body that made it. Over the years, she grew increasingly
familiar with these diseases, particularly since she developed three more:
Sjögren syndrome, Raynaud syndrome, and irritable-bowel syndrome.
Norton is far from alone. "Progress in Autoimmune Diseases Research," a 2004
report from the National Institutes of Health's Autoimmune Diseases Coordinating
Committee (ADCC), details more than 80 chronic and often disabling diseases
recognized at least in part as autoimmune. These conditions can affect any part
of the body, often causing a spectrum of symptoms that make straightforward
diagnosis a challenge. They include a handful of relatively common illnesses,
including diabetes, rheumatoid arthritis, and multiple sclerosis (MS), plus
dozens of rare conditions.
"We know that these diseases occur predominantly in women in their childbearing
years, just when they have the biggest family responsibilities." -Noel Rose
Despite diverse manifestations, many autoimmune diseases share common genetic
and molecular origins, explains Virginia Ladd, founder of the American
Autoimmune Related Diseases Association. The result is that many patients, such
as Yvonne Norton, have more than one autoimmune disorder. In some cases,
multiple autoimmune diseases cluster within the same family.
Yvonne Norton addresses a reception at the UK House of Commons at the launch of
Lupus - A GP Guide to Diagnosis, which she compiled. Holding the microphone
is Graham Hughes, a consultant physician at St. Thomas Hospital in London.
Courtesy of Yvonne Norton
The Overall Burden
Because autoimmune diseases can be hard to diagnose, and because many of them
are rare, collecting data on their prevalence is a real challenge, says
epidemiologist Glinda Cooper of the US Environmental Protection Agency. "When
you talk about autoimmune diseases as a general category, it is hard to find
good data to get a grasp of it," she says. The best estimates from the ADCC
suggest that autoimmune diseases affect 14.7-23.5 million Americans, which
represents as much as eight percent of the population. Plus, for reasons that
aren't clear, the incidence of some autoimmune diseases seems to be increasing.
According to Noel Rose, director of the Center for Autoimmune Disease
Research at Johns Hopkins School of Public Health and lead author of the ADCC
report, the wide margin of uncertainty in that report's figures reflects a lack
of solid data on autoimmune disease epidemiology in the United States. The
challenge becomes even bigger globally. "The usual 'wisdom' is that autoimmune
diseases are a problem mostly of developed countries," he says. "That may or may
not be true; I've never been completely comfortable with the idea."
Still, scientists do know one thing about the epidemiology of autoimmune
diseases: Women are affected more than men, at least in most cases. "We know
that these diseases occur predominantly in women in their childbearing years,
just when they have the biggest family responsibilities," says Rose.
This imbalance varies from disease to disease, says Cooper. In 2003, she
coauthored a report1
on the epidemiology of autoimmune diseases, perhaps the most detailed
publication on the topic so far. That report shows that in the more common
conditions, such as MS, the imbalance tilts so that affected patients are
roughly two-thirds female. "In some diseases, however, the degree of
disproportion is very extreme," Cooper says. For example, at least 85% of
patients with thyroiditis, systemic sclerosis, systemic lupus erythematosus, and
Sjögren disease are female. In data from the Centers for Disease Control and
Prevention for 1995, well-defined autoimmune diseases were one of the top-10
causes of death for women under the age of 65 years.2
The struggle to track these diseases matches the pharmaceutical industry's
failure to treat them. For example, drugs for rheumatoid arthritis evolved from
injectable gold in the 1930s to biologics today, but treatment results remain
mediocre. According to Anthony Manning, vice president and global head of
inflammation, autoimmunity, and transplant research at Roche, only about
one-third of patients with rheumatoid-arthritis get "significant benefit," even
with today's best therapies.
Such lacklustre results probably arise from rheumatoid arthritis'
heterogeneity, varying in mechanism between individuals and within the same
individual over time. Many other autoimmune diseases include similar
variability, which thwarts effective treatment. Still, some members of the
pharmaceutical community feel optimistic about improving results in the very
near future. "Five years ago, we didn't have the plethora of tools that we have
today," says Andrew C. Chan, vice president of research immunology and antibody
engineering at Genentech. "If you only have one or two tools, it's hard to go
and attack any disease and say, 'I have the answer.' It's like having a hammer,
and you're walking around looking for the nail."
The sheer numbers of patients with autoimmune diseases places an enormous
cost on health systems. In USA, for example, "there's no doubt that about 60% of
our healthcare budget is on the treatment of autoimmune diseases and their
complications," says Imran Khan, director of the Cidpusa, most of it spent on
diabetes, multiple sclerosis, and arthritis. "There's no question we're talking
about a major burden, and these costs are increasing every year."
I "In the past, most autoimmune diseases were treated with relatively cheap
drugs like prednisone, which costs about $30 a month," says Ladd. "That's now
changing." For example, the antitumor necrosis factor (TNF)-alpha drug Remicade
(infliximab) costs about $1,250 per month, and it is prescribed for ankylosing
spondylitis, Crohn disease, psoriatic arthritis, rheumatoid arthritis, and
ulcerative colitis. "The drug is a very good breakthrough, but the costs in the
future will be enormous," Ladd says.
"There are very, very strong correlations between MS and [people] being out of
work and unable to earn a decent living." -Sharon Haffenden
For the patients with autoimmune diseases, drug costs are only one part of
the equation. Yvonne Norton, for example, built an extension on her home to
provide a downstairs bathroom and office area, because stairs are difficult for
her. Also, financial difficulties challenge many autoimmune patients, says
Sharon Haffenden, director of research and services at the UK's MS Society.
"We're working here with diseases that are diagnosed when people are in their
20s or 30s, so it's going to have an impact for people in the prime of their
lives." Research conducted by the UK charity, Leonard Cheshire, shows that
people disabled with diseases such as MS are seven times more likely to be out
of work and claiming disability. "There are very, very strong correlations
between MS and [people] being out of work and unable to earn a decent living,"
As Yvonne Norton found, the economic costs of autoimmune diseases are only
one part of a complex story. These conditions, chronic and debilitating as they
are for the patients, also have an impact on loved ones, such as Norton's
husband Peter. "I always say that I'm the one with lupus, but Peter's the one
who suffers from lupus," Norton says with a rueful laugh. "It's changed his
life, too. He can't take certain jobs now because there are times when I just
need him to be able to get home quickly, and that sort of thing."
This is a common experience, adds Haffenden. "In many cases, the spouse very
much becomes a [caretaker]," she says. "They often have to reduce their own
working hours or give up working altogether.
More than 70% of the costs to society from disability are borne by informal
caregivers, such as husbands or wives, according to the research of Paul McCrone
and Martin Knapp from Kings College London. (The UK's MS Society funded the
research.) "In MS, we've found that despite all the brouhaha over drug costs,
the main cost to society is through informal care," Haffenden says. Overall,
multiple sclerosis costs the United Kingdom roughly £1 billion a year, she adds.
Also, because autoimmune diseases more commonly affect young and middle-aged
women, children also feel the impact. "My two sons were eight and five when I
was diagnosed," says Norton. "They've grown up with a mum in a wheelchair. It
was a big deal for them."
Yvonne Norton puts it this way: "It's a complete lifestyle change for those
who have got it badly. We just know it's going to be there forever."
Most autoimmune diseases affect women more than men. In most of the disease
shown here, women get them four or more times more often than men. Only two of
the diseases show roughly equal gender percentages, and just one - ankylosing
spondylitis - occurs more often in men.