Autoimmune disease and stress: what the research really shows

“My doctor asked whether I had been under stress lately. I said yes. And ever since, I have been wondering whether I brought this illness on myself.”

I hear this sentence, in various forms, more often than I would have expected. A woman says it, diagnosed with rheumatoid arthritis a few months after a relationship ended. A man whose Crohn’s disease first flared up in the year he was caring for his dying father. A young mother whose endocrinologist confirmed Hashimoto’s thyroiditis after the birth. The question about stress was well meant — the doctor was simply trying to see the whole picture. But it planted a different, heavier question in the person: is it my fault?

This piece is an attempt to separate what we really know about the link between stress and autoimmune disease, what is probable, and what is simply a story we like to hear because it gives us a sense that the illness is under our control. And right at the start, something that applies to everything that follows: an autoimmune disease is diagnosed and treated by a doctor — a rheumatologist, endocrinologist, gastroenterologist, neurologist or dermatologist. Nothing below replaces treatment, and none of it means the illness is “all in your head”.

What an autoimmune disease actually is

The immune system’s job is to tell apart what belongs to us from what is foreign — bacteria, viruses, damaged cells. In autoimmune diseases this distinction goes wrong: the immune system starts attacking the body’s own tissues. In rheumatoid arthritis the joints, in multiple sclerosis the sheaths around the nerves, in Hashimoto’s thyroiditis the thyroid, in psoriasis the skin, in coeliac disease the lining of the gut.

These illnesses are very different from one another, but they share a few things. They arise from an interplay of several factors: genetic predisposition, hormones (they are more common in women), infections, smoking, the make-up of the gut flora and the environment. They often run in waves — periods of calm followed by flares. And it is precisely these waves that make people search so often for a pattern: why now, of all times?

This is where stress enters the story. Not as the only culprit, but as one of the factors that can tip the balance for someone who is already close to the edge.

What the largest study so far shows

For a long time, research on stress and autoimmunity was small and mostly relied on asking patients what had been happening to them before they fell ill. In 2018, however, Huan Song and colleagues published an analysis of Swedish national registers in JAMA that included more than a hundred thousand people diagnosed with a stress-related disorder — post-traumatic stress disorder, acute stress reaction or adjustment disorder. They compared them with people without such a diagnosis and with their own brothers and sisters.

The finding: people with a stress-related diagnosis had a risk of developing an autoimmune disease in the following years that was roughly 36 per cent higher. The link held even in the comparison with siblings, which means it cannot be put down entirely to shared genes or a shared home environment. It was stronger in younger people.

This is an important finding, but it needs to be read carefully. These were people whose distress was severe enough to receive a psychiatric diagnosis — not everyday stress at work. And a 36 per cent higher risk means the illness was somewhat more common among them, not that most of them fell ill. The great majority of people diagnosed with PTSD did not develop an autoimmune disease.

Research on early adversity paints a similar picture. As part of the well-known study of adverse childhood experiences (ACE), Shanta Dube and colleagues showed in 2009 that adults who had lived through more severe adversity as children were more often hospitalised for autoimmune diseases decades later. The body, it seems, remembers for a long time.

The path from stress to inflammation

How could stress affect the immune system at all? We have better answers to this question today than we did thirty years ago, although they are still far from complete.

When we are under pressure, the body triggers the stress response: the sympathetic nervous system and the axis between the hypothalamus, the pituitary and the adrenal glands. The adrenal glands release cortisol, one of whose jobs is to restrain inflammation. In the short term, this is useful. In 2004, Suzanne Segerstrom and Gregory Miller summarised three decades of research and showed that brief, acute stress actually mobilises the immune system, while long-lasting stress begins to throw it out of tune.

In 2012, Sheldon Cohen and colleagues described one of the likely mechanisms. In people who are under stress for a long time, immune cells respond less well to cortisol — they become less sensitive to it. The brake that is meant to stop inflammation loosens. There may be enough cortisol, but the cells no longer “hear” it well. The result is inflammation that lasts longer and is more pronounced than it would otherwise be. You can read more about what happens in the body under prolonged strain in the knowledge base entry chronic stress.

It matters what this picture says and what it does not. It says there is a biologically plausible route by which prolonged strain affects inflammation. It does not say that this route decides, in every individual, whether they will fall ill.

Stress and flares: where the evidence is strongest

If the question of whether stress causes autoimmune disease is still open, the question of whether it affects the course of an existing disease has been studied somewhat better. Most of the data concern multiple sclerosis. In 2004, David Mohr and colleagues published a meta-analysis in the BMJ of studies that followed people with multiple sclerosis over time, and found that stressful life events were associated with a higher risk of relapse.

A similar link appears in inflammatory bowel disease, psoriasis and rheumatoid arthritis, although the studies there are smaller and less consistent. The piece Skin and stress: eczema, psoriasis and rashes under pressure looks at psoriasis in more detail.

For someone already living with the illness, this is actually useful information. It does not mean a flare is their fault. It does mean that looking after your load — sleep, boundaries at work, support at home — is a legitimate part of caring for the illness, not mere self-indulgence.

What research does not show

Online, you will have no trouble finding claims that “autoimmune diseases come from suppressed emotions” or that “the body attacks itself because you don’t like yourself”. There is no evidence for this. These are metaphors that may help someone, but they load many people with guilt they should never have to carry.

Even the often-quoted observation that a large share of patients went through severe stress before their illness began should be read with care. This figure comes mostly from studies that asked people in retrospect, when they already knew their diagnosis. Whoever falls ill looks for a reason — and in every life, something hard can be found in the past year. Memory is not a neutral archive; once we know how the story ended, we pick out the events from the past that fit the ending.

That is why studies like the Swedish one matter: they measure stress before the illness, independently of what will happen later. They confirm the link, but it is more modest than the patients’ accounts would suggest.

Illness as stress: a circle running both ways

In conversations about stress and illness, people often forget that the arrow points the other way too. An autoimmune disease is in itself a severe and long-lasting stress. Pain, fatigue, unpredictable flares, check-ups, medication with side effects, worry about work, money and the future. Many people also experience low mood — which is no surprise, since inflammation itself is linked to mood. I have written about how mood shows up in the body, and the other way round, in Depression and the body: pain, fatigue and digestion.

And so a circle forms: the illness causes stress, stress may contribute to flares, flares cause more stress. This circle cannot be broken by willpower. But you can loosen it a little in several places at once — with treatment led by your doctor, and by having a place where you are allowed to say how hard it is.

A particular trap is constantly watching your body. Anyone who has been through a severe flare starts reading every small sign as a forecast of the next one. This vigilance is understandable, but it can grow into exhausting scanning that keeps the tension going all by itself. If you recognise yourself in this, you may find Health anxiety: when every symptom means the worst helpful.

An invisible illness in the family and the relationship

As a therapist in training in relational family therapy, I also look at illness through relationships. Autoimmune diseases are often invisible. A person looks healthy, yet in the morning cannot open a jar. Those around them don’t see it and don’t understand it, so the person who is ill often ends up carrying a double load: fighting the illness while also proving they are not making it up.

Illness reshuffles the roles in a family. A partner becomes a carer, children take on more than they should, and the person who is ill feels like a burden. Some hide the illness so as not to worry others. Others withdraw because they are tired of explaining. In the long run both increase loneliness — and loneliness is in itself one of the stronger long-term stressors.

(composite, not a real person)
“When he asks how I am, I say I’m fine. Because I know he’s tired too.”
“What happens when you say you’re fine?”
“He relaxes. And I’m left alone with it.”
“And if you told him, just once, how it really is?”
A long silence. “I’m afraid he’d get tired of it. That I’d be too much.”

In a conversation like this, it often turns out that the partner is not waiting for the illness to disappear, but for permission to be there. When the illness starts being talked about as something that is happening to both of them, the load does not get lighter, but it gets shared.

Small things can help here too: an agreed word or sign that says “today is a bad day”, with no explanation needed. Or one task a week that the partner takes over without being asked. It is not about the person who is ill becoming passive, but about them not having to prove, every single time, that things are hard.

Exercise: a map of your flares

This exercise is not meant for finding someone to blame, but for gathering information you can take to your doctor and that shows you where you do have some influence. As a starting point you can use the template from the knowledge base, the diary of bodily signs.

1. Every evening for four weeks, write down two numbers from 0 to 10: how strong your symptoms were today and how much strain you felt under. Don’t think about it for too long; the first number is good enough. The distress scale can help you.
2. Add three short notes: how you slept, whether you might have had a cold or another illness, and whether anything changed with your medication. For women it also makes sense to note the phase of the menstrual cycle.
3. After four weeks, look through your notes and see whether days of strain are followed by worse symptom days — the same day, or a day or two later. You may find a pattern, or you may not. Both are valuable information.
4. Take your notes to the doctor who is treating you. Not so that you draw conclusions yourself, but so that your doctor has a clearer picture.
5. Choose one thing you can influence — for example going to bed half an hour earlier, or one “no” a week — and try it for the next month. Not everything at once. One thing.

If, while you are keeping these notes, you notice that the exercise unsettles you further — that you start checking every day whether the strain is “too much” and whether it will hit you again — stop. The aim is an overview, not a new source of control.

Where this story does not apply

I want to be very clear here, because with this topic the risk of misuse is high.

Stress is not the explanation for every flare. Flares also come during calm periods, with an infection, with a change in medication, or for no known reason. If you look for stress behind every setback, you will find it — and with it, guilt that does not help.

Managing stress does not replace treatment. Perhaps the most telling evidence for this comes from a study in multiple sclerosis: in 2012, Mohr and colleagues tested a stress management programme and found that during the programme participants had fewer new lesions in the brain as seen on MRI. But the effect did not last after the programme ended. For a serious illness, this is an interesting addition, not an alternative. Never stop or change your medication without agreeing it with your doctor.

You don’t have to be calm to be a good patient. The pressure to stay positive is itself a stress. You are allowed to be angry, sad and frightened about your illness. Feelings you are not allowed to express weigh more than the ones you can say out loud.

When symptoms change, go to your doctor first. A new or different symptom is not the moment for a psychological explanation. Once physical causes have been checked and treatment is under way, then it is time to ask how you can live with the illness with less suffering.

What psychotherapy can offer — and what it can’t

Psychotherapy does not treat autoimmune disease. But it can help with the things that come with the illness and that medication does not reach: grieving for the life the illness has changed (more on how loss affects the body in Grief and the body: why we fall ill more often after a loss), anxiety about flares, conversations with your partner and children, and finding your own rhythm between what you can manage and rest.

When bodily symptoms persist despite good test results, that is a different story, which I described in “The tests are normal, but it still hurts”; a short explanation of the term is in the knowledge base under psychosomatics. With autoimmune diseases, the test results are often not normal — and that is exactly why it matters that psychological help stands beside treatment, not in place of it. I have gathered practical ways to help the body out of a state of readiness in How the body calms down: methods with evidence, not just advice.

And back to the sentence from the beginning. No, you did not bring this illness on yourself. Stress may be one of many small stones in a mosaic that nobody sees in full. What you can do today is not repair the past, but take care that living with the illness becomes at least a little easier.

What to remember

• Severe, long-lasting stress is linked to a somewhat higher risk of autoimmune disease and to more flares — but it is not their only cause.
• One likely mechanism is that, under prolonged stress, immune cells respond less well to cortisol, so inflammation lasts longer.
• Accounts of “I was under stress before I fell ill” are less reliable, because of hindsight, than studies that measure stress in advance.
• The illness is itself a stress — the circle runs both ways, so caring for yourself is part of treatment, not a luxury.
• Doctor first: psychological help stands beside treatment, never in place of it. And the illness is not your fault.