Dementia and autoimmune disease

Find out about a new link between dementia and autoimmune disease.

A study published in the Journal of Epidemiology and Community Health suggests that people admitted to hospital with an autoimmune disease are 20 per cent more likely to be admitted with dementia later on.

The researchers, based at the University of Oxford, looked at the data of more than 1.8 million people admitted to hospital with autoimmune disease from 1998 to 2012.

Of the 25 autoimmune diseases investigated – including coeliac disease, multiple sclerosis, rheumatoid arthritis and ulcerative colitis – 18 were associated with dementia in this way. Although the type of dementia was not always documented, in cases where it was known, the risk was stronger for vascular dementia than for Alzheimer’s.

Dr Clare Walton at the Society said, ‘The causes of dementia are complex and we are increasingly learning about links between dementia and other health conditions.

‘This research reinforces earlier evidence that shows the immune system plays an important role in developing dementia, which opens up new avenues to find effective treatments. Alzheimer’s Society is funding a study to test whether a rheumatoid arthritis treatment can also work for people with early stage Alzheimer’s disease.’

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Care and cure magazine: Summer 17

Care and cure is the research magazine of Alzheimer's Society is for anyone interested in dementia research.
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Care and cure is the research magazine of Alzheimer's Society is for anyone interested in dementia research.
Subscribe now


My sister has recently been diagnosed with an autoimmune disease. She has received both Covid-19 shots and a booster just last week. Since then, and the last few days, she has had problems with her memory. Her husband took her the hospital today and they have admitted her. Could her autoimmune system & the Covid shot be the reason for this development?

Hi Bev,

We're very sorry to hear about your sister and hope she’s recovering well in hospital. In terms of knowing whether the COVID booster was responsible for her symptoms, it’s impossible to know for sure.

Some people have reported their autoimmune conditions flaring up after COVID vaccinations, but these would appear to be very rare. By contrast, we have much stronger evidence that COVID vaccinations are likely protect people living with autoimmune conditions from becoming severely unwell with COVID-19.

Memory problems and ‘brain fog’ can happen for many reasons, including some autoimmune diseases. In many cases they are temporary but in some diseases they can get worse. Each person’s autoimmune condition will be different and so getting advice from the specialist team who manages it is really important.

Those who feel they have had a side effect from the COVID-19 vaccine can report it via the MHRA Yellow Card reporting site:

Wishing your sister a speedy recovery.

Alzheimer's Society Knowledge team

Finally, and thank you for your article: "Dementia and Autoimmune Disease". I have been looking for brain health research articles as I have been recovering from Hashimoto's Thyroiditis for the past two years and despite my ongoing, dedicated antiinflammatory and targeted nutrition diet, my brain is still less than it was before my Hashimoto's took a turn for the worst two years ago. I am not giving up despite this significant news regarding dementia. The USA researchers seem to dance around the hard facts instead of sharing them with us fully when it is bad news, we still want to know. Again, thank you for your shared knowledge.