Patients with autoimmune diseases were 20% more likely to be admitted to a hospital with dementia in the future.
Individuals with autoimmune diseases may have an increased risk of developing dementia, a new study found.
In a study published in theJournal of Epidemiology & Community Health, investigators found that autoimmune diseases such as multiple sclerosis (MS), lupus, or psoriasis showed a statistically significant association with dementia.
However, the authors stressed that the study did not prove that autoimmune disease caused dementia but merely showed the conditions are associated with a higher risk.
“How do [autoimmune diseases] affect the brain? We don’t know, although others have suggested that chronic inflammation, possibly autoimmune effects, or possibly both, may have a role in Alzheimer’s,” said study co-author Dr Michael Goldacre.
For the study, investigators examined data from more than 1.8 million individuals in England who had been admitted to a hospital with an autoimmune disease between 1998 and 2012.
Patients admitted for treatment of an autoimmune disorder were 20% more likely to be admitted to the hospital in the future with dementia compared with individuals admitted for other causes.
When the findings were broken down by type of dementia, the results showed that autoimmune disease only increased the risk of Alzheimer’s disease by approximately 6%. Instead, they appeared to have a much stronger impact on the risk of vascular dementia.
The risk of vascular dementia was 28% higher in individuals with autoimmune diseases, according to the study.
When the diseases were broken out, the investigators found that individuals with MS had nearly double the risk of dementia. Psoriasis was associated with a 29% increased risk; lupus a 46% increased risk; and rheumatoid arthritis a 13% increase; and Crohn’s disease was associated with a 10% increased risk.
The increased risk for vascular dementia may be caused by the effects autoimmune diseases have on the circulatory system, according to the authors.
The authors noted that the study is observational and does not prove a direct cause-and-effect link. Furthermore, the associations found were small.