Study links autoimmune diseases including MS to increased risk of dementia

PEOPLE who suffer autoimmune diseases such as multiple sclerosis (MS) may have an elevated risk of developing dementia, a new study suggests.

Researchers have linked autoimmune disease to an increased risk of going on to suffer dementia.

There are more than 80 different types of autoimmune disease, from multiple sclerosis and type 1 diabetes and rheumatoid arthritis.

These conditions are illnesses or disorders that occur when healthy cells get attacked by the body’s immune system.

It has been suggested autoimmune and inflammatory activity may have a role in the development of dementia.

In a bid to investigate, the researchers from the University of Oxford, examined 25 different autoimmune diseases.

Of these, 18 showed significant positive associations with dementia, according to the study published in the Journal Of Epidemiology And Community Health.

The authors drew information on hospital admissions data between 1998 to 2012 for England.

During the monitoring period, more than 1.8 million people were admitted with an autoimmune disease, ranging from just over 1,019 people with the rare condition, Goodpasture’s syndrome, in which antibodies attack the lungs and kidneys, to more than 316,043 with rheumatoid arthritis.

Overall people admitted to hospital with an autoimmune disease were 20% more likely to have a subsequent admission for dementia than those without an admission for an autoimmune disease.

They found the risk varied between different conditions: People with MS had an almost double risk, those with psoriasis showed a 29% heightened risk and people with Addison’s disease showed a 48% increased risk.

The type of dementia was not always documented but, for those recorded, the risk was 6% higher for Alzheimer’s disease, and 28% higher for vascular dementia.

People with rheumatoid arthritis showed an elevated risk of vascular dementia but it appeared having the condition seemed to be protective for Alzheimer’s disease.

The researchers emphasise the size of the associations they found was small, so further research would be needed to confirm or refute the findings.

“Our findings should be considered as indicative rather than definitive,” the authors caution.

But they added: “People admitted to hospital with an autoimmune disease, likely to be those at the severe end of the disease spectrum, do appear to have an elevated risk of dementia.

“This finding is consistent with autoimmune disease predisposing to vascular risk and vascular dementia.

“It is also, separately, consistent with the theory that Alzheimer’s disease may have an autoimmune component.”