Autoimmune diseases, which happen when the immune
system attacks the body’s own cells, overwhelmingly afect women, but there’s
new hope on the horizon.
A strong immune system is the body’s first line of defence
against foreign invaders such as viruses and bacteria but if something derails
it, it’s not just the body’s enemies that come under fire but also healthy
cells and tissues this is what happens in the 80 or so autoimmune diseases
(ADs) that – taken together – are the third most common cause of serious
illness, after heart disease and cancer. Four million people in the UK are
affected, and almost three times as many women as men.
“Something – we don’t know exactly what – causes the immune
system to go into overdrive, triggering the production of antibodies against
the body’s own tissues,” explains Professor David D’Cruz, former editor of the
Journal Of Autoimmune Diseases, who leads London’s St Thomas’ Hospital’s Louise
Coote Lupus Unit.
Autoimmune
diseases are the third most common cause of serious illness, after heart
disease and cancer
ADs can strike at any organ: the pancreas (Type 1 – and some
now think Type 2 – diabetes), the nervous system (multiple sclerosis), the
joints (rheumatoid arthritis), the thyroid (Graves’ and Hashimoto’s diseases),
and the bowel (ulcerative colitis and Crohn’s disease). They can also affect
the whole body, as in lupus.
Why women?
The origins may lie in the changes the immune system has to
make to cope with pregnancy and childbirth. “There’s no clear answer but
oestrogen and other female hormones may increase the activity of the immune
system. Genetic differences between men and women may also play a part,”
observes Professor Alan Silman, medical director of Arthritis Research UK.
There’s still no
clear answer why women are afftected more than man
The Family connection
ADs tend to cluster in families.“There’s also a lot of overlap,” says Professor
D’Cruz. So if you have rheumatoid arthritis, for example, you have a higher
risk of Type 1 diabetes. Meanwhile, if you have MS or lupus, there’s also a
greater risk of developing thyroid problems.
Genetic Markers have been detected but, as yet, there’s no
test that can predict or prevent you developing an AD. Scientists have,
however, pinpointed several “pathways” shared by common ADs, and the hope is
that these may provide new targets for treatment. For example, people with
coeliac disease who stick closely to a strict gluten-free diet are far less
likely to develop other ADs.
Allergies are a separate process
They happen when the immune system has an exaggerated
reaction to foreign bodies rather than to self”. However, people with lupus are
more likely to have allergies and are often allergic to sulphur-containing
drugs.
