By Dennis Thompson

WEDNESDAY, March 1, 2017 (HealthDay News) -- People with -- conditions that cause a person's immune system to turn against the body -- appear to have an increased risk of developing , a new British study suggests.

Researchers found that 18 out of 25 different autoimmune diseases, such as , or , "showed a statistically significant association with dementia," said study co-author Dr. Michael Goldacre. He's a professor of public health at the University of Oxford.

But Goldacre and other experts stressed that the study didn't prove that autoimmune diseases cause dementia. The research only showed that these conditions are associated with a higher risk of dementia.

Specifically, the study found that people with appeared to have nearly double the risk of dementia. was associated with a 29 percent increased risk of dementia. was linked to a 46 percent increased risk, and with a 13 percent increased risk.