Polymyalgia Rheumatica and Giant Cell
Arteritis
Contents
What Are Polymyalgia Rheumatica and Giant Cell Arteritis?
Polymyalgia
rheumatica is a rheumatic disorder that is associated with moderate
to severe muscle pain and stiffness in the neck, shoulder, and hip
area. Stiffness is most noticeable in the morning. This disorder may
develop rapidly--in some patients, overnight. In other people, polymyalgia rheumatica develops more gradually. The cause of
polymyalgia rheumatica is not known; however, possibilities include
immune system abnormalities and genetic factors. The fact that
polymyalgia rheumatica is rare in people under the age of 50
suggests it may be linked to the aging process.
Polymyalgia
rheumatica may go away without treatment in 1 to several years. With
treatment, the symptoms of polymyalgia rheumatica are quickly
controlled, but relapse if treatment is stopped too early.
Giant cell
arteritis, also known as temporal arteritis and cranial arteritis,
is a disorder that results in swelling of arteries in the head (most
often the temporal arteries, which are located on the temples on
each side of the head), neck, and arms. This swelling causes the
arteries to narrow, reducing blood flow. Early treatment is critical
for good prognosis.
How Are Polymyalgia Rheumatica and Giant Cell Arteritis Related?
It is unclear
how or why polymyalgia rheumatica and giant cell arteritis are
related, but an estimated 15 percent of people in the United States
with polymyalgia rheumatica also develop giant cell arteritis.
Patients can develop giant cell arteritis either at the same time as
polymyalgia rheumatica or after the polymyalgia symptoms disappear.
About half of the people affected by giant cell arteritis also have
polymyalgia rheumatica.
When a person
is diagnosed with polymyalgia rheumatica, the doctor also should
look for symptoms of giant cell arteritis because of the risk of
blindness. With proper treatment, the disease is not threatening.
Untreated, however, giant cell arteritis can lead to serious
complications including permanent vision loss and stroke. Patients
must learn to recognize the signs of giant cell arteritis, because
they can develop even after the symptoms of polymyalgia rheumatica
disappear. Patients should report any symptoms to the doctor
immediately.
Who Is at Risk?
White women
over the age of 50 are most at risk of developing polymyalgia
rheumatica and giant cell arteritis. Women are twice as likely as
men to develop the conditions. Both conditions almost exclusively
affect people over the age of 50. The average age at onset is 70
years. Polymyalgia rheumatica and giant cell arteritis are quite
common. In the United States, it is estimated that 700 per 100,000
people in the general population over 50 years of age develop
polymyalgia rheumatica. An estimated 200 per 100,000 people over the
age of 50 develop giant cell arteritis.
What Are the Symptoms?
The primary
symptoms of polymyalgia rheumatica are moderate to severe stiffness
and muscle pain near the neck, shoulders, or hips. The stiffness is
more severe upon waking or after a period of inactivity, and
typically lasts longer than 30 minutes. People with this condition
also may have flu-like symptoms, including fever, weakness, and
weight loss.
Early symptoms
of giant cell arteritis also may resemble the flu. People are likely
to experience headaches, pain in the temples, and blurred or double
vision. Pain may also affect the jaw and tongue.
How Are Polymyalgia Rheumatica and Giant Cell Arteritis Diagnosed?
No single test
is available to definitively diagnose polymyalgia rheumatica. To
diagnose the condition, a physician considers the patient’s medical
history, including symptoms that the patient reports, and results of
laboratory tests that can rule out other possible diagnoses.
The most
typical laboratory finding in people with polymyalgia rheumatica is
an elevated erythrocyte sedimentation rate, commonly referred to as
the sed rate. This test measures how quickly red blood cells fall to
the bottom of a test tube of unclotted blood. Rapidly descending
cells (an elevated sed rate) indicate inflammation in the body.
While the sed rate measurement is a helpful diagnostic tool, it
alone does not confirm polymyalgia rheumatica. An abnormal result
indicates only that tissue is inflamed, which also is a symptom of
many forms of arthritis and/ or other rheumatic diseases. Before
making a diagnosis of polymyalgia rheumatica, the doctor may perform
additional tests to rule out other conditions, including rheumatoid
arthritis, because symptoms of polymyalgia rheumatica and rheumatoid
arthritis can be similar.
The doctor may
recommend a test for rheumatoid factor (RF). RF is an antibody
sometimes found in the blood. (An antibody is a special protein made
by the immune system.) People with rheumatoid arthritis are likely
to have RF in their blood, but most people with polymyalgia
rheumatica do not. If the diagnosis still is unclear, a physician
may conduct additional tests to rule out other disorders.
Doctors and
patients both need to be aware of the risk of giant cell arteritis
in people with polymyalgia rheumatica and should be on the lookout
for symptoms of the disorder. Severe headaches, jaw pain, and vision
problems are typical symptoms of giant cell arteritis. In addition,
physical examination may reveal an abnormal temporal artery: tender
to the touch, inflamed, and with reduced pulse. Because of the
possibility of permanent blindness, a temporal artery biopsy is
recommended if there is any suspicion of giant cell arteritis.
In a person
with giant cell arteritis, the biopsy will show abnormal cells in
the artery walls. Some patients showing symptoms of giant cell
arteritis will have negative biopsy results. In such cases the
doctor may suggest a second biopsy.
What Are the Treatments?
Polymyalgia
rheumatica usually disappears without treatment in 1 to several
years. With treatment, however, symptoms disappear quickly, usually
in 24 to 48 hours. If there is no improvement, the doctor is likely
to consider other possible diagnoses.
The treatment
of choice is corticosteroid medication, usually prednisone.
Polymyalgia rheumatica responds to a low daily dose of prednisone.
The dose is increased as needed until symptoms disappear. Once
symptoms disappear, the doctor may gradually reduce the dosage to
determine the lowest amount needed to alleviate symptoms. The amount
of time that treatment is needed is different for each patient. Most
patients can discontinue medication after 6 months to 2 years. If
symptoms recur, prednisone treatment is required again.
Nonsteroidal
anti-inflammatory drugs (NSAIDs) such as aspirin and ibuprofen also
may be used to treat polymyalgia rheumatica. The medication must be
taken daily, and long-term use may cause stomach irritation. For
most patients, NSAIDs alone are not enough to relieve symptoms.
Giant cell
arteritis carries a small but definite risk of blindness. The
blindness is permanent once it happens. A high dose of prednisone is
needed to prevent blindness and should be started as soon as
possible, perhaps even before the diagnosis is confirmed with a
temporal artery biopsy. When treated, symptoms quickly disappear.
Typically, people with giant cell arteritis must continue taking a
high dose of prednisone for 1 month. Once symptoms disappear and the
sed rate is normal and there is no longer a risk of blindness, the
doctor can begin to gradually reduce the dose. When treated
properly, giant cell arteritis rarely recurs.
People taking
low doses of prednisone rarely experience side effects. Side effects
are more common among people taking higher doses. But all patients
should be aware of potential effects, which include:
-
fluid
retention and weight gain
-
rounding of
the face
-
delayed
wound healing
-
bruising
easily
-
diabetes
-
myopathy
(muscle wasting)
-
glaucoma
-
increased
blood pressure
-
decreased
calcium absorption in the bones, which can lead to osteoporosis
-
irritation
of the stomach
People taking
corticosteroids may have some side effects or none at all. A patient
should report any side effects to the doctor. When the medication is
stopped, the side effects disappear. Because prednisone and other
corticosteroid drugs change the body’s natural production of
corticosteroid hormones, the patient should not stop taking the
medication unless instructed by the doctor. The patient and doctor
must work together to gradually reduce the medication.
What Is the Outlook?
Most people
with polymyalgia rheumatica and giant cell arteritis lead
productive, active lives. The duration of drug treatment differs by
patient. Once treatment is discontinued, polymyalgia may recur; but
once again, symptoms respond rapidly to prednisone. When properly
treated, giant cell arteritis rarely recurs.
What Research Is Being Conducted To Help People Who Have Polymyalgia
Rheumatica and Giant Cell Arteritis?
Researchers
studying possible causes of polymyalgia rheumatica and giant cell
arteritis are investigating the role of genetic predisposition,
immune system abnormalities, and environmental factors. Scientists
also are looking for markers of the diseases, exploring treatments,
and studying why the two disorders often occur together.
With funding
from the National Eye Institute, a new mouse model of giant cell
arteritis is being used to examine interactions between the immune
system and blood vessels to explain tissue damage.
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