It is not known exactly what causes Sjögren’s syndrome, but it is thought to be linked to a problem with the immune system.

The immune system

The immune system is designed to recognise any foreign object that presents a threat to the body, such as a virus or bacterium, and to attack it with special chemicals known as antibodies (produced by white blood cells).

In Sjögren’s syndrome, the immune system mistakes healthy tissue for a foreign body and attacks it with antibodies. The parts of the body usually affected are the tear, saliva and vaginal glands, which are collectively known as the exocrine glands.

The antibodies damage the exocrine glands so that they can no longer function normally. There is also some evidence that the immune system damages the nerves that control these glands, further reducing their effectiveness.

The immune system can go on to damage other parts of the body, such as muscles, joints, blood vessels, nerves and (less commonly) organs.

Possible triggers for Sjögren’s syndrome

Primary Sjögren’s syndrome

Most researchers believe that primary Sjögren’s syndrome is triggered by a combination of genetic and environmental factors.

The general thinking is that certain people are born with specific genes that make them more vulnerable to a faulty immune system. Then many years later, an environmental factor, possibly a common virus, triggers the immune system to stop working properly.

The female hormone oestrogen seems to play an important role as well. Sjögren’s syndrome mostly occurs in women, and symptoms usually start around the time of the menopause, when levels of oestrogen begin to fall. Falling oestrogen levels can contribute to dryness and it may be that this worsening of dryness makes the condition more noticeable.

Secondary Sjögren’s syndrome

Sjögren’s syndrome can occur later in the course of other autoimmune conditions, such as rheumatoid arthritis or lupus. This is known as secondary Sjögren’s syndrome.

If you have one of these other conditions, you will already be under the care of a specialist who will diagnose Sjögren’s syndrome if you start experiencing eye and mouth dryness.

The exocrine glands

The reason that Sjögren’s syndrome can cause such a wide range of troublesome symptoms is that your saliva and tear glands play a vital role in protecting your mouth and eyes.

The importance of tears

We usually only notice our tears when we cry, but our eyes are always covered by a thin layer of tears, known as a tear film.

Tears are made up of a mix of water, proteins, fats, mucus and infection-fighting cells. Tears serve several important functions:

• lubricating the eye
• keeping it clean and free of dust
• protecting the eye against infection
• helping to stabilise your vision

The importance of saliva

Saliva also serves several important functions, including:

• keeping the mouth and throat naturally lubricated
• aiding digestion by moistening food and containing enzymes that can break down certain starches
• acting as a natural disinfectant (saliva contains antibodies, enzymes and proteins that protect against some common bacterial and fungal infections)

Sjögren’s syndrome is not often life-threatening, but it is linked to more serious problems.

Non-Hodgkin’s lymphoma

It is estimated that people with Sjögren’s syndrome are 44 times more likely to develop non-Hodgkin’s lymphoma than people without Sjögren’s syndrome.

Non-Hodgkin’s lymphoma is a cancer of the lymphatic system. The lymphatic system is a series of vessels and glands (lymph nodes) that are spread throughout your body, much like your blood vessels.

While this increased risk may sound alarming, the chance of a person with Sjögren’s syndrome developing non-Hodgkin’s lymphoma is still small, as it only affects about 5% of patients.

If you have Sjögren’s syndrome, be alert for the main early symptom of non-Hodgkin’s lymphoma – a painless swelling in a lymph node (gland), usually in the neck, armpit or groin. Report any swollen lymph nodes to your GP.

Read more about non-Hodgkin’s lymphoma.

Eye damage

If dry eyes are not treated, they can become infected and develop ulcers on the surface of the eyes, called corneal ulcers.

If left untreated, corneal ulcers can lead to loss of vision and permanent damage to your sight.

Pregnancy

If you are planning to become pregnant and have Sjögren’s syndrome, ask your GP to test for certain antibodies that may be present in Sjögren’s syndrome and are known to cause lupus in newborn babies. In very rare cases, the antibodies can also cause heart defects in babies.

If these antibodies are found, there should be no reason why you cannot proceed with the pregnancy, but your child may need additional specialist care during pregnancy and after the birth.

Read more about antenatal appointments.

Other conditions

There are a number of other conditions that have been linked to Sjögren’s syndrome, including: 

• peripheral neuropathy – a condition that commonly involves the loss of sensation in the hands and feet
• Raynaud’s phenomenon – restricted blood flow to the hands, which can cause the hands to feel cold, numb and painful
• kidney problems, such as inflammation or kidney stones
• an underactive thyroid gland, which can lead to tiredness and weight gain
• irritable bowel syndrome, which can cause abdominal pain and irregular bowel movements
• teeth cavities

Sjögren’s syndrome can be difficult to diagnose, as the symptoms are similar to those of other health conditions.

Also, you may see different health professionals for your different symptoms, such as a dentist for a dry mouth, an optician for dry eyes and a gynaecologist for a dry vagina, which can make it harder to reach a firm diagnosis.

See your GP if you experience any symptoms of dryness, especially of your eyes and mouth.

Screening questions

Experts in the field have come up with a series of screening questions, which may be useful if you are worried you may have Sjögren’s syndrome.

If you answer yes to most of the questions below, you may have Sjögren’s syndrome and will probably be advised to go for further testing by your GP.

• Have you had daily, persistent, troublesome dry eyes for more than three months?
• Do you keep having a sensation of sand or gravel in your eye?
• Do you need to use eye drops containing tear substitutes more than three times a day?
• Have you had a daily feeling of dry mouth for more than three months?
• Do you keep getting swollen salivary glands (located between your jaw and your ears)?
• Do you frequently drink liquids to help you swallow food?

Further testing

Sjögren’s syndrome can usually be diagnosed by looking at the results of the screening questions and carrying out a number of clinical tests. These may include:

• tear break-up time and Schirmer tests
• a lip biopsy
• blood tests
• salivary flow rate

These are explained below.

Tear break-up time and Schirmer tests

These two tests are usually carried out by an ophthalmologist (a doctor who specialises in the treatment of eye conditions).

The tear break-up time test is a measure of how effective your tear glands are. During the test, a non-toxic dye is dropped onto the surface of your eye. The distinctive colour of the dye allows the ophthalmologist to see how well your tear film is functioning and how long it takes for your tears to evaporate. This test is also called a slit lamp examination.

In the Schirmer test, small strips of blotting paper are placed under your eyelid. After five minutes, the strips are removed and then studied to see how much of the paper was soaked with tears.

Lip biopsy

During a lip biopsy, a small sample of tissue is removed from your inner lip and examined under a microscope. You will be given an injection of local anaesthetic into the inner surface of your lower lip (which numbs the area), then a small cut is made to remove a few of your minor salivary glands.

Clusters of lymphocytes (a type of white blood cell) in the tissue can indicate the presence of Sjögren’s syndrome.

Blood tests

Blood tests are carried out to look for special antibodies known as anti-Ro and anti-La (or SS-A and SS-B), which are known to be produced when the immune system has been affected by Sjögren’s syndrome.

However, the antibodies are only present in about 60% of patients with Sjögren’s syndrome, so it is possible to have a negative blood test result and still have the condition.

Salivary flow rate

During this test, you are usually asked to spit as much saliva as you can into a cup over a five-minute period. The amount of saliva is then weighed or measured. The test is a good way of measuring how much saliva your glands are producing each minute. An unusually low flow rate can indicate Sjögren’s syndrome.

Sjögren’s (pronounced Show-grin’s) syndrome is an autoimmune condition where the body’s immune system attacks glands that secrete fluid, such as the tear and saliva glands.

The condition can cause widespread effects. Inflammation within the glands reduces the production of tears and saliva which causes the main symptoms of Sjögren’s syndrome, dry mouth and dry eyes.

In women (who are most commonly affected), the glands responsible for keeping the vagina moist can also be affected, leading to vaginal dryness.

Read more about the symptoms of Sjögren’s syndrome.

Health professionals classify Sjögren’s syndrome as either:

• primary Sjögren’s syndrome, when the condition develops by itself and not as the result of another condition
• secondary Sjögren’s syndrome, when the condition develops in combination with another autoimmune condition, such as lupus or rheumatoid arthritis

What causes Sjögren’s syndrome?

The cause of Sjögren’s syndrome remains unknown, but research suggests that it is triggered by a combination of genetic, environmental and possibly hormonal factors.

It is believed that some people are more vulnerable to the condition when they are born and that certain events, such as a viral or bacterial infection, can trigger the problems with the immune system.

Read more about the causes of Sjögren’s syndrome.

Who is affected?

Sjögren’s syndrome is a relatively common condition, affecting 3-4% of adults in the UK. It’s the second most common autoimmune condition after rheumatoid arthritis. However, the condition remains under recognised and often under treated.

Sjögren’s syndrome can develop at any age, but most cases begin in people aged 40-60 years old. Women account for about 90% of cases.

Diagnosis

Sjögren’s syndrome can be difficult to diagnose because it has similar symptoms to other conditions and there is no single test for it.

If a doctor suspects Sjögren’s syndrome, they may ask you questions about your symptoms. You may also have tests to study your tear and saliva production.

Read more about diagnosing Sjögren’s syndrome.

Treating Sjögren’s syndrome

There is no cure for Sjögren’s syndrome, but a number of treatments can help control symptoms.

Eye and mouth dryness can usually be controlled with artificial tears and saliva.

Good eye and mouth hygiene are also important, as the chances of infection are increased if you have Sjögren’s syndrome. Taking care of your eyes and mouth can help to prevent problems such as corneal ulcers and tooth decay.

For more serious cases, medication or surgery may be used.

Read more about treating Sjögren’s syndrome.

Complications

Sjögren’s syndrome is rarely life-threatening, but it can sometimes lead to complications.

For example, your eyesight could be permanently damaged if the reduced tear production is not treated.

Sjögren’s syndrome also increases your risk of developing non-Hodgkin’s lymphoma, which is a cancer of the lymph glands. However, the chances are still low, at around 5%.

Women with Sjögren’s syndrome are at a higher risk of having children with lupus or heart abnormalities. This doesn’t mean you can’t have children, but any pregnancy will be closely monitored for potential problems.

Read more about the complications of Sjögren’s syndrome.

The most commonly reported symptoms of Sjögren’s syndrome are a dry mouth and dry eyes, both of which can lead to other associated symptoms.

However, these symptoms can be common in old age and most people with dry eyes or mouth do not have Sjögren’s syndrome.

Many women also experience dryness of the vagina, which can make sexual intercourse painful.

Associated symptoms of dry mouth

Associated symptoms of dry mouth include:

• tooth decay, leading to an increased risk of tooth loss
• dry cough
• difficulty swallowing and chewing
• hoarse voice
• difficulty speaking
• swollen salivary glands (located between your jaw and your ears)
• repeated fungal infections of your mouth (oral thrush), symptoms of which can include coated or white tongue

Associated symptoms of dry eyes

Associated symptoms of dry eyes include:

• a burning or stinging sensation in your eyes
• itchy eyes
• a feeling that there is a piece of sand or gravel in your eyes
• irritated and swollen eyelids
• sensitivity to light (photophobia)
• tired eyes
• a discharge of mucus from your eyes

Symptoms can become worse when you are in a windy or smoky environment. Air-conditioned buildings and travelling on aeroplanes can also make symptoms worse.

Other symptoms of Sjögren’s syndrome

In more serious cases of Sjögren’s syndrome, the immune system can attack other parts of the body as well as the tear, saliva and vaginal glands, causing a wide range of symptoms and conditions such as:

• dry skin
• tiredness and fatigue, which are common features and can amount to total exhaustion in some cases 
• muscle pain
• joint pain, stiffness and swelling
• vasculitis (inflammation of blood vessels)
• difficulty concentrating, remembering and reasoning

There is no cure for Sjögren’s syndrome, but treatment can help to relieve the symptoms, such as eye and mouth dryness.

Sjögren’s syndrome affects everyone in different ways, so your treatment plan will be tailored to suit you.

Eye care

Artificial tears

Mild to moderate cases of dry eye can usually be successfully treated with eye drops that contain ‘artificial tears’, a liquid that mimics tears. These eye drops are available from a pharmacist without a prescription.

There are many different types of eye drops, so you can try different brands to find the one that works best for you.

A short-term dose of eye drops containing corticosteroids may be recommended if your eyes become severely irritated. However, long-term use of corticosteroids is not recommended as they can cause serious side effects.

To minimise the chance of any side effects from corticosteroids, you will be prescribed the lowest effective dose for the shortest possible time.

Moisture chamber spectacles

Some cases of dry eye can be treated with specially made glasses known as moisture chamber spectacles. These wrap around the eyes much like goggles and help retain moisture and protect the eyes from irritants.

Moisture chamber spectacles used to be unpopular as they had a strange design and people were embarrassed to wear them. Now they are becoming a more popular treatment option as the modern designs look like sports sunglasses.

Surgery

If your dry eyes fail to respond to other forms of treatment, surgery may be an option.

One widely used technique is punctual occlusion, which involves using small plugs to seal the tear ducts into which the tears drain. This should help keep the eye better protected by tears.

Temporary plugs made of silicone are normally used first to see if the surgery has a positive effect. If it does, more permanent plugs can be used to replace the silicone plugs.

Mouth care

Looking after your mouth

You can use a number of techniques to keep your mouth lubricated and to deal with any associated symptoms, including:

• maintaining good oral hygiene to prevent tooth decay and gum disease. Read more about preventing tooth decay
• increasing your fluid intake
• using sugar-free chewing gum to stimulate the production of saliva
• sucking ice cubes to help lubricate your mouth and reduce dryness
• regularly using mouth rinses to soothe the mouth and protect it against infection

If you are a smoker, you should try to quit. Smoke both irritates the mouth and increases the rate at which saliva evaporates.

Read more about quitting smoking.

Saliva substitutes

There are a number of saliva substitute products that can help lubricate your mouth. However, they do not replicate the role of saliva in preventing infection, so you will still need to maintain excellent oral hygiene.

Saliva substitutes are available as a spray, lozenge (medicated sweet), gel, or gum. Your GP or pharmacist can tell you which product is most suitable for you.

Medication for Sjögren’s syndrome

Pilocarpine

The medicine pilocarpine is often used to treat the symptoms of dry eyes and mouth. Pilocarpine stimulates the tear and saliva glands to produce more saliva and tears.

Side effects of pilocarpine include:

• excessive sweating
• nausea
• diarrhoea
• heartburn
• abdominal (tummy) pain
• an increased need to go to the toilet

Less common side effects include:

• vomiting
• heart palpitations
• high blood pressure
• blurred vision

For some people, the side effects of pilocarpine are mild. Others find that the side effects outweigh the benefits.

Do not take pilocarpine if you have asthma or chronic obstructive pulmonary disease (COPD), or if you are pregnant or breastfeeding.

Hydroxychloroquine

You may also be recommended a medicine called hydroxychloroquine. Hydroxychloroquine has been shown to slow the immune system’s attack on the tear and saliva glands. It can also help reduce any associated symptoms of muscle pain, joint pain, and stiffness.

You will need to take hydroxychloroquine for several weeks before you notice any improvements and it could be six months before you experience the full benefit of the treatment.

Side effects are uncommon and usually mild, including:

• nausea
• skin rash
• loss of appetite
• stomach cramps
• vomiting

In very rare cases, hydroxychloroquine can damage the retina, affecting vision. You will probably be asked to attend an eye examination so the state of your retina can be checked before you start treatment. Regular eye examinations (usually at least once a year) are also recommended after you begin treatment.

Hydroxychloroquine should not be used by pregnant and breastfeeding women.

Treating other symptoms of Sjögren’s syndrome

Dry skin

Several soaps and creams are specifically designed for people with dry skin. Your pharmacist or GP can advise you.

Vaginal dryness

The symptoms of vaginal dryness can be treated using a lubricant. Some women also consider using oestrogen creams or hormone replacement therapy (HRT).

Muscle and joint pains

Muscle and joint pains can be treated with an over-the-counter non-steroidal anti-inflammatory drug (NSAID), such as ibuprofen. If this does not work, see your GP, as stronger NSAIDs are available on prescription.

NSAIDs can increase your risk of developing stomach ulcers and internal bleeding, particularly if they are taken on a long-term basis. Ideally, take NSAIDs with food or shortly after eating. This will help minimise the risk of the medicine upsetting your stomach.

If you find swallowing NSAIDs difficult because of your dry mouth, you can try an NSAID cream that is rubbed into affected joints.

NSAIDs are not recommended for women who are pregnant or breastfeeding, or for people with pre-existing risk factors for cardiovascular or kidney conditions.

General advice

Some simple tips can help prevent many of the problems that are associated with Sjögren’s syndrome, these include:

• have a dental check-up every six months
• practise good dental hygiene, brushing, flossing and using mouthwash regularly
• avoid eating too many sweet foods
• avoid strong and perfumed soaps, use special creams and soaps from your pharmacist
• avoid dry environments (such as air-conditioned offices) where possible
• do not drink too much alcohol
• get information about self-help groups through the British Sjögren’s Syndrome Association