Sjogren's syndrome is a disorder of the immune system (the body’s defence system against infection). White blood cells attack the body’s tear and saliva glands, which reduces the amount of saliva and tears produced. This causes a dry mouth and dry eyes, along with other related symptoms.
In women (who are most commonly affected), the glands responsible for keeping the vagina moist can also be affected, leading to vaginal dryness. For more information, see Sjogren’s syndrome – symptoms.
Sjogren’s syndrome is an autoimmune disease. This term refers to any disease caused by a faulty immune system attacking the body’s healthy cells and tissues (see box, left).
Primary and secondary disease
Health professionals classify Sjogren's syndrome as either:
- primary Sjogren's syndrome, when the condition develops by itself and not as the result of another condition
- secondary Sjogren's syndrome, when the condition develops in combination with another autoimmune condition, such as lupus or rheumatoid arthritis (see box, left)
The cause of Sjogren's syndrome remains unknown, but research suggests that the condition is triggered by a combination of genetic, environmental and possibly hormonal factors (see Sjogren’s syndrome – causes for more information).
How common is Sjogren's syndrome?
Sjogren's syndrome is a relatively common condition. In the UK, 3-4% of adults are thought to be affected. This makes it the second most common autoimmune condition after rheumatoid arthritis. However, the condition remains under recognised and often under treated.
Sjogren's syndrome can develop at any age, but most cases begin in people aged 40-60 years old. It is most common in women, who account for 9 out of 10 cases.
There is no cure for Sjogren's syndrome, but a number of treatments can help control symptoms. These include eye drops and medicines to stimulate saliva production.
Complications of Sjogren’s syndrome include tooth decay, non-Hodgkin’s lymphoma and eye damage from corneal ulcers (see Sjogren’s syndrome – complications for more information).
Early diagnosis and treatment can reduce the risk of complications and improve the quality of life for people with Sjogren’s syndrome. However, the disorder is often under diagnosed because the symptoms are common of many other conditions.