Girls, Early Adversity, and the Autoimmune Connection
To find out more about the correlation between childhood Chronic
Unpredictable Toxic Stress and autoimmune disease in women, I turned to
DeLisa Fairweather, PhD, associate professor of toxicology at the Johns Hopkins
Bloomberg School of Public Health and Mayo Clinic, one of today’s reigning
experts on women, sex differences, and autoimmune disorders. Fairweather is
coauthor, with Vincent Felitti and Robert Anda, of a landmark study that
examined 15,357 adults who had enrolled in the original Kaiser/CDC study on
Adverse Childhood Experiences in 1995. Fairweather looked at each ACE Study
participant’s medical records to see if there was a relationship between having
had Adverse Childhood Experiences and later being diagnosed and hospitalized
with an autoimmune disease.
Fairweather and I meet at a downtown Baltimore restaurant to talk about her
findings. She is short, brunette, and so affable a lunch date, you’d hesitate to peg
her as a lab director who spends eleven-hour days managing a toxicology lab
and writing grants. She has an infectious enthusiasm for science.
In her study of Adverse Childhood Experiences, Fairweather looked at just
twenty-one of the most common autoimmune conditions, including rheumatoid
arthritis, lupus, and thyroiditis. The initial results were shocking. “The
relationship between ACEs and autoimmune disease, particularly in women, was
so striking that we feared no one would believe our numbers.” She says, even
after the data were checked and double-checked, “We found that a remarkable,
disproportionate number of individuals who had experienced childhood
adversity were later hospitalized for an autoimmune condition—and a
disproportionate number of these individuals were women. The more childhood
adversity a woman had, the higher her risk became, and the more likely she was
to end up in the hospital at some point in her adult life in order to be treated for
an autoimmune condition.”
For every ACE Score a woman had, her likelihood of being hospitalized with
any one of these twenty-one autoimmune diseases increased by 20 percent. For
instance, a woman with three Adverse Childhood Experiences had a 60 percent
greater chance of being hospitalized with an autoimmune disease than a woman
with none.
For every ACE Score a man had, his chances of being hospitalized for an
autoimmune disease increased 10 percent—also a very significant and disturbing
correlation. Still, the risk that childhood adversity would lead to an autoimmune
disease that was so serious it required hospitalization in adulthood was twice as
high for women as it was for men.
“Stress causes autoimmune symptoms to become worse,” says Fairweather.
“So if any chronic inflammatory disease could be linked to early childhood
stress, we figured it would be autoimmune diseases. But we were completely
unprepared for how powerful the relationship would turn out to be.”
In many other studies, Fairweather continues, “in order to see the relationship
between ACEs and chronic disease, you might have to look at patients who had
four or five ACEs to see such a significant correlation. But with autoimmune
diseases, we saw a very notable increase even among women who had had only
two ACEs.”
Fairweather confesses that the link she found was so stark that she and her
colleagues decided not to report the relationship between women who had more
than two Adverse Childhood Experiences and their likelihood of developing
autoimmune disease. “The correlation was so significant for those with higher
ACE Scores that we didn’t think anyone would
believe
us—you just don’t see
such extreme relationships reported in the scientific literature.”
Take Kendall, with her ACE Score of 6. According to Fairweather, Felitti, and
Anda’s research, Kendall’s chance of having an autoimmune disease once she
reached adulthood was 140 percent greater than that of a woman who had
experienced no Adverse Childhood Experiences at all. And, in fact, Kendall at
fifty-two was diagnosed with three autoimmune diseases.
Indeed, if you are diagnosed with one autoimmune disease, you are at a three-
times-greater risk of developing other autoimmune diseases.
This link between being female, facing adversity in childhood, and later
developing a serious autoimmune disease is so consequential that it resembles
the link between smoking and lung cancer, drunk driving and car accidents, and
unprotected sex and pregnancy.
Fairweather and her colleagues also found that one in three adults who had
faced adversity prior to the age of eighteen was admitted into the hospital for an
autoimmune condition some thirty years later—and this was especially true for
rheumatic autoimmune diseases such as lupus, rheumatoid arthritis, and
Sjögren’s syndrome. And, says Fairweather, “80 percent of these patients were
women.”
Other studies from around the world also bear out this striking relationship
between childhood adversity and autoimmune disease in adulthood. While
autoimmune diseases strike women three times more than men, for certain
illnesses, that ratio is even higher. Women suffer from Hashimoto’s thyroiditis at
a rate of 10:1 compared with men. In lupus, that rate is 9:1. In Sjögren’s
syndrome, 9:1. In antiphospholipid syndrome, 9:1. In primary biliary cirrhosis,
9:1. Autoimmune disease is one of the top ten leading causes of death in women
under the age of sixty-five.
Although Fairweather, Felitti, and Anda did not include multiple sclerosis in
their study sample, researchers recently found that patients with MS score
significantly higher on the Childhood Trauma Questionnaire. The association
between experiencing early life stress and later developing MS—another
autoimmune disease that primarily strikes women—is compelling.
To best understand Fairweather’s findings, we need to remember the basic
physiological differences between women and men. Women are, generally,
physically smaller than men and our hearts and lungs are much smaller in size.
Yet our anatomy makes added room to carry a fetus in order to create new
human life.
“Our smaller heart, lungs, and other organs still have to be able to do
everything a human male does—pump oxygen, circulate blood, run fast, think
fast, be awake sixteen or seventeen hours a day—and have the necessary fuel to
carry a child to term so that it can survive outside the womb,” says Fairweather.
Do double duty, on half the machinery.
Women can do so much more on so much less partly because we have much
higher baseline levels of the hormone estrogen than men do. Estrogen, which is
really a catchall phrase for several hormones, acts as a kind of chemical
messenger, carrying information and instructions from one group of our cells to
another. It’s produced not only in female ovaries but also in our adrenal glands.
Women also have higher baseline levels of glucocorticoids, or GCs—which
include the steroid-hormone cortisol. GCs, including cortisol, help to protect
women by increasing our ability to regulate inflammation—at least when our
fight-or-flight stress response is functioning properly.
For instance, if we have a sudden injury, or have to fight off an infection,
glucocorticoids help to reduce that inflammation by suppressing proteins that
would promote more inflammation. Extra help from GCs in regulating
inflammation ensures that pregnant women who have to deal with sudden
inflammation won’t miscarry; it’s nature’s way of making sure that we keep our
embryo safe and carry it until term, even if we are hurt or ill. Our immune
system is poised, all the time, to protect our ability to carry another life.
This is the upside to having a more pronounced and robust cortisol response
than men, at least when our stress reactivity is working well. Estrogen also helps
the immune system produce fighter antibodies. Antibodies go after any foreign
invader, such as a virus or bacteria.
This is why, says Fairweather, “when women have the flu, or get a vaccine,
we have a different, more robust immune response to infection and
immunization than men do; we develop a greater antibody response.”
On the downside, estrogen can also increase the number of autoantibodies
women have. And autoantibodies—antibodies that turn against you and attack
the body itself—attack and tear down organs and tissue in every known
autoimmune disease.
Multiple, chronic stressful events lead to changes in the developing brain that
dysregulate our inflammatory response, allowing inflammation to flourish and
build, slowly and silently. The fact that women have a higher baseline level of
glucocorticoids complicates things, says Fairweather. “Men start with lower
baseline levels of cortisol, so when stressful events happen, cortisol levels have
to rise faster in order to help men to successfully regulate inflammation.”
In contrast, women already have higher baseline levels of glucocorticoids,
because of estrogen. “Normally, when women are healthy and unstressed, we
have a more protective cortisol response,” says Fairweather. But when women—
and especially girls—face stressful events and the inflammatory response
becomes dysregulated, something happens in us that doesn’t happen in men: Our
high levels of GCs go down. Our bodies become a lot
less
able to regulate
inflammation.
As girls begin to come into puberty, at around age ten, they also start to have
higher levels of estrogen, so they start to produce higher levels of antibodies and
autoantibodies. This equation means that when women face chronic ongoing
stress, our glucocorticoids stop properly regulating inflammation. At the same
juncture, our estrogen is still high, which means autoantibodies can run amok.
High autoantibodies, low system controls. This combination, says
Fairweather, “vastly increases the likelihood that girls will grow up to later
develop an autoimmune disease, especially a rheumatic autoimmune disease like
lupus or Sjögren’s syndrome.”
You might think of it this way: GCs are like the castle gate that’s lowered
over a moat to keep those in the castle safe, to allow in just the right number of
soldiers, or antibodies, and to keep out rogue mercenaries—or autoantibodies.
Girls make more of these rogue autoantibodies, which are elevated by estrogen.
But when girls face chronic ongoing early stress, normally protective GCs aren’t
able to do the job. The castle gate starts to give way, allowing, in this case,
damaging rogue autoantibodies to begin an all-out attack.
Fairweather adds, “It takes time for inflammation and autoantibodies to cause
damage to organs in the weeks, months, and years after a stressful event. A child
can undergo chronic stress at twelve, and it can take thirty years or longer for the
immune damage caused by that chronic adversity to progress to a clinically
recognizable disease.”
At that late date, the correlation between that stressed little girl and the ill
woman is obvious to neither the patient nor her physician.
The fact that women have more estrogen as they enter the teen years may not be
the only explanation. According to Margaret McCarthy, PhD, professor of
neuroscience at the University of Maryland School of Medicine, male resilience
may stem from the male immune response, which “is programmed by high
testosterone.” Testosterone suppresses the immune system, which is another
reason why men are so much less likely to get many autoimmune diseases,
including MS.
Despite these scientific findings, most doctors miss autoimmune disease in
women. Recent studies show that the average woman sees five doctors over four
and a half years before receiving a proper diagnosis—and nearly half of patients
are labeled as “chronic complainers” in the early stages of their illness.
McCarthy, who researches sex differences in the brain, offers an additional
hypothesis as to why women face higher rates of adult chronic conditions
including autoimmune disease. “We have good evidence that women are more
stressed than men in the modern world,” says McCarthy. Girls not only face
more adverse experiences when they enter adolescence but also, studies show,
are exposed to more interpersonal and other stressors in their day-to-day lives
than boys.
Girls are more likely to be criticized for not being attractive or sexy, or for
being too sexual, or too fat, or too “flat.” Throughout their lives, women are also
physically vulnerable, paid less for the same work that men do, and have less
career security while carrying more responsibility for child care and caregiving
for parents. When women become successful, they are more likely to be seen as
aggressive rather than assertive, strident rather than strong.
Girls come of age witnessing these pervasive inequities, and this serves as a
chronic stressor that creates wear and tear on the immune system, setting up girls
for epigenetic changes and disease. “This idea that girls come of age in a more
stressful context doesn’t negate any of the other causes we’ve discussed, but
complements them,” says McCarthy. “And yet physicians do not take seriously
the cost that this societal stress has on the female body.”
When women are overtly victimized, this correlation becomes startlingly
clear. Bessel van der Kolk, MD, a trauma and recovery psychiatrist and author of
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