Connect Immune Research, a coalition of medical research charities, said many autoimmune conditions are becoming more common, with some increasing in incidence by as much as nine per cent a year.
It has published a report, which shows direct and indirect costs to the UK for just three autoimmune conditions – type one diabetes, rheumatoid arthritis and multiple sclerosis – add up to more than £13 billion a year.
Altogether, there are more than 80 autoimmune conditions known to science, but the reason for the rise is not known and the charities are campaigning for change in the way that research is approached.
The report suggests the rising incidence and costs mean autoimmunity in the UK needs greater recognition and investment as a distinct research area, alongside the likes of cancer, infectious disease and dementia.
Four million people in the UK are known to be living with at least one autoimmune condition, but the report highlights that people often live with more than one.
Chloe Gillum, 25, a paediatric nurse from Somerset, lives with three autoimmune conditions.
At the age of nine she was diagnosed with type one diabetes and went on to develop vitiligo and an underactive thyroid, which caused secondary Raynaud’s disease. All need daily medication.
She said: “One of the hardest things about living with autoimmune conditions is people not understanding the impact this has on my life.”
In people with autoimmune conditions, their immune system mistakenly attacks healthy cells in the body.
Other examples of autoimmune conditions are coeliac disease and psoriasis.
Connect Immune Research is made up of type one diabetes charity JDRF, the MS Society and Versus Arthritis, and is supported by the British Society for Immunology.
Genevieve Edwards, director of external affairs at the MS Society, said: “Around four million people in the UK have an autoimmune condition and we must find a way to prevent that figure from escalating.”
Karen Addington, UK chief executive of JDRF, said: “This alarming and unexplained rise in autoimmune conditions among the UK population must be confronted.
“These conditions are causing pain, difficulty and lost opportunities in work and life.”