Introduction: RA is not a
generic term for just any type of arthritis. It
also is not a term applied to any form of severe arthritis.
It is a specific type of arthritis that begins in the soft
tissue around the joint known as the synovium (sin-O-vee-um).
RA affects 1% of the U.S. population, with women
outnumbering men 2:1 to 4:1. While the peak age of
onset is in the 30’s to 50’s, RA can begin at any age.
It is a disease that progresses most rapidly within the
first two years of onset, and those afflicted with RA have
twice the mortality rate of individuals of the same age in
the general population.
Features of RA:
The basic problem in RA is inflammation of the
synovium, causing swelling, pain, and morning stiffness, and
which can lead to irreversible joint damage and loss of
function. The joints most often affected are the
wrists and the small joints of the hands, usually the first
and second row of knuckles past the wrists. Other
commonly affected joints include those in the balls of the
feet, the ankles, the knees, the elbows, and the shoulders.
While neck involvement is common, the lower back is
typically spared. The pattern of arthritis has a
strong tendency to be symmetrical, affecting the same joints
on both sides of the body.
When joints become affected in RA, they don’t
simply hurt; they become progressively damaged. The
inflamed synovium, when not properly treated, can invade the
bone and cartilage surrounding the joint and result in
irreversible damage and loss of function. This may
result in not only pain, but also limited mobility,
deformity, and difficulty using the impaired joint.
This process does not discriminate according to age, race or
gender; all affected with RA are at risk for complications.
While the joint disease is the most striking
manifestation of RA, the inflammation will often affect
other organs. Up to 40% of RA patients will have
abnormalities in lung function, which are often subtle and
may go unnoticed. Many patients, however, can
experience serious lung damage requiring more aggressive
therapy. Roughly 25% of patients will have dry eyes
and dry mouth known as secondary Sjögren’s syndrome (see
section on Sjögren’s), and about 20% will have inflammation
that may cause irritation of the eyes, or less commonly,
vision loss. A condition known as Felty’s syndrome
causes low blood counts and frequent enlargement of the
spleen, and rheumatoid vasculitis (inflammation of the blood
vessels) may result in rash, skin ulcers, or less commonly
damage to the nerves or other organs. Both of these
conditions are infrequently encountered in RA (about 1% of
patients).
In recent years, the risk of cardiovascular
disease in RA has been a focus of several studies. It is
likely that the aforementioned increase in mortality seen in
RA vs. the general population is in large part due to the
increased rate of heart disease in RA patients, which is
nearly twice that of age-matched individuals without RA.
This risk appears to be due in large part to the effect
inflammation has on the lining of blood vessels, resulting
in plaque buildup, narrowing of blood vessels, and an
increased tendency for these vessels to clot. The good news
is that many studies would suggest treating the inflammation
of RA aggressively and at an earlier stage will reduce these
risks.
Diagnosis: RA is
predominantly diagnosed by a thorough review of a patient’s
symptoms and physical examination. While laboratory
studies help in the evaluation, no laboratory test can
either establish or rule out a diagnosis of RA. The
rheumatoid factor (RF), markers of inflammation, and a newer
antibody know as anti-CCP are useful studies and are often
used to predict the severity of RA in individual patients.
X-rays are also useful diagnostic tools, particularly films
of the hands and feet, and can be used to monitor disease
progression by assessing the degree of joint damage.
Because RA may be difficult to identify at its
earliest stages, and because prompt intervention has
resulted in improved outcomes in several studies, the
American College of Rheumatology (ACR) is in the process of
revising criteria for diagnosis of this disease. Patient
within the first year of the onset of symptoms may
demonstrate findings on physical examination or laboratory
testing that are less specific than those with well
established disease, leading to delays in diagnosis and
therapy. The new criteria are designed to help physicians
recognize RA in patients who would have previously been
labeled "undifferentiated." More advanced imaging techniques
such as ultrasound or magnetic resonance imaging (MRI) have
also been advanced as methods for demonstrating joint
inflammation not detectable on physical examination or
damage not apparent on plain x-rays.
Treatment (see
Medications section): Therapy in RA has two
goals: reducing symptoms and preventing joint damage and
disability. We have more tools available to treat RA
today than ever before, and studies have documented that
early treatment with specific medications has a long-term
impact on the course of the disease. While all
therapies have potential side effects, the consequences of
not treating RA are generally much greater.
Your doctor will work carefully with you to select the right
medications for you as an individual.
Non-steroidal anti-inflammatory drugs (NSAIDs)
such as ibuprofen (Motrin) and simple analgesics such
as acetaminophen (Tylenol) or even narcotic-strength pain
relievers have a role in treating RA. These therapies,
however, are limited to their effects on reducing day-to-day
symptoms and have no effect on the long-term course of the
disease. Many of these medications may be given in
combination with other RA therapies to reduce pain in
inflamed joints.
Corticosteroids such as prednisone may be
very effective in rapidly reducing pain and swelling in
inflamed joints, both when given orally and injected
directly into a joint. Some evidence suggests that
these medications may even slow down joint damage.
Long-term side effects, however, limit the use of
corticosteroids in RA. Generally speaking, steroids
should be used for disease flares, for brief periods of
time, or in low doses to avoid these complications (see
Medications section).
Disease-modifying anti-rheumatic drugs
(DMARDs) should be the mainstay of therapy for most
patients with RA. Generally speaking, the sooner they
are started after the onset of symptoms, the more effective
they are at treating the disease. Ideally, DMARDs
should be initiated within three months of disease onset to
achieve an optimal response. Because patients are
individuals, your doctor will work with you to determine
which DMARD is appropriate for the severity and stage of
your disease.
All of the agents listed below fall under this
category and can be further subdivided into traditional
DMARDs and biologic DMARDs. These latter agents
are specifically designed to attack key targets in the
inflammatory processes involved in RA. Because of the cost
and potential side effects of these agents, biologic DMARDs
are typically reserved for patients who fail to respond
adequately to traditional DMARDs or in patients with highly
active disease who are at high risk for progressive damage
and/or disability. Careful monitoring of disease activity
under the supervision of an experienced physician is
necessary to assist in making the decision to advance or to
withdraw therapy. An effort has been made by many
specialists in rheumatology in recent years to more
carefully monitor disease activity and adjust medications
accordingly.
Traditional DMARDs
Anti-malarial drugs are generally among
the safest of the DMARDs but are generally utilized to treat
milder RA. Hydroxychloroquine (HCQ), marketed under
the trade name Plaquenil, takes 3 to 6 months to begin
working and can be used either by itself or in combination
with other DMARDs. The only potential complication
requiring monitoring is that of damage to the retina, the
layer in the back of the eye, which can potentially impair
color vision. While this is of concern, it occurs in
only one of 1,000 people taking the drug and is detectable
before serious damage occurs if monitored by your eye doctor
every 6-12 months. HCQ doses of less than 6.5
mg/kg/day generally have a very low incidence of retinal
damage.
Sulfasalazine (SSZ) was developed many
decades ago to treat RA and is also commonly used to treat
Crohn’s disease, an inflammatory intestinal disorder.
SSZ takes effect in 1 to 3 months and seems to have a modest
effect on slowing down joint damage in RA. This drug
also seems to be more effective in patients who are "seronegative"
(with a negative RF). The most common side effect of
SSZ is stomach upset, which may be eliminated by using a
coated preparation of the drug. Allergic reactions are
also no unusual. Serious problems, such as a drop in
the white blood cells or acute damage to the liver, are
unusual and typically occur early in the course of therapy,
if at all. Blood tests to monitor for these
complications will generally pick up any problems before
they become severe.
Methotrexate (MTX) is perhaps the most
popular and most commonly prescribed DMARD among
rheumatologists, and for good reason. MTX slows joint
damage, improves symptoms and physical functioning in RA
patients, and has an onset of action of 1 to 3 months after
starting the medication. It is taken once weekly in
the form of pills or injections, with injections being
associated with better availability of the medication and
often less side effects. Nausea, mouth sores, thinning
of the hair, lowering of blood counts, susceptibility to
infection, and liver damage are among the more common side
effects and can be reduced by taking folic acid or folinic
acid (Leucovorin) supplementation. Rarely, acute lung
injury may occur that can resemble pneumonia. Despite
these potential side effects, problems with MTX can
generally be detected with regular lab monitoring every 1 to
2 months. Most importantly, patients with RA taking
MTX have a mortality rate that is only 40% of the mortality
rate of RA patients not taking the drug. This finding
seems to indicate that for most patients, the trade-off
between benefit and side effects is very good.
Leflunomide (LEF), marketed under the
trade name Arava, is a relatively new drug used to treat RA.
It is taken orally once daily and begins to take effect in 1
to 3 months. The efficacy of LEF is similar to that of MTX,
and it does seem to slow down the development of joint
damage. LEF can result in nausea, diarrhea, hair loss, and
liver damage, but the incidence of lowered blood counts and
infection are lower than with MTX.
Miscellaneous drugs that are less commonly
used to treat RA but which may be useful in certain
individuals include minocycline, azathioprine (Imuran),
injectable gold, and D-penicillamine.
Minocycline is an antibiotic that is also used
to treat acne and other skin diseases. Like HCQ, minocycline
is usually used to treat milder RA, but one study showed
that if started within one year of disease onset and
continued for one year, up to 40% of patients went into
remission. Other than nausea, dizziness, and sun sensitivity
in some individuals, minocycline is usually very well
tolerated.
Imuran is a medication that suppresses the
immune system and may be effective at reducing the
inflammation in the joints of RA patients as well as in
other organ systems, such as the lungs. Increased infection
rates, lowered blood counts, and liver damage are potential
side effects.
Injectable gold is given once weekly in the
doctor’s office and must be monitored closely, including
blood and urine tests with each visit to screen for low
blood counts and protein in the urine. Rashes, damage to the
liver, and lung damage are also potential side effects.
While effective in treating RA, the inconvenience, toxicity,
and delayed onset of action (4 to 6 months) have made gold a
less popular choice among rheumatologists and patients.
D-penicillamine, a drug also used to bind
toxic levels of heavy metals in the body, has a therapeutic
effect in RA. The toxicity of this agent, however (blood
cells, kidneys, liver, secondary autoimmune diseases), has
led to less frequent use in treating RA patients.
Biologic DMARDs
TNF antagonists are perhaps the most
exciting class of medications to be recently introduced for
the treatment of RA. Currently, there are now 5 available
medications in this class: etanercept (Enbrel), infliximab (Remicade),
adalimumab (Humira), Certolizumab pegol (Cimzia), and
Golimumab (Simponi). Enbrel is given as a once weekly
injection, Remicade is given as an intravenous infusion
every 4-8 weeks, Humira is administered as an injection
every 2 weeks, Cimzia as an injection given every 2-4 weeks,
and Simponi as an every 4 week injection. Each of these
medications inhibits a substance known as tumor necrosis
factor (TNF) in one way or another. TNF is known to play a
key role in inflammation in inflammation and joint damage in
RA, and for this reason these medications are highly
effective in controlling both the symptoms of the disease
and the joint damage. In fact, some studies suggest that
these medications actually halt joint damage in RA
patients.
Each of the TNF antagonists may begin working
within a few weeks of starting therapy. While individual
patients may respond more favorably to one agent over
another, all of these drugs seem to have similar efficacy.
Disadvantages of these therapies include cost, inconvenience
of injections or infusions, injection site or infusion
reactions, and suppression of the immune system. Respiratory
infections occur in increased frequency in patients treated
with TNF antagonists, and those exposed to tuberculosis may
experience reactivation of their disease. For this reason, a
TB skin test is recommended prior to starting therapy.
Patients with multiple sclerosis or severe congestive heart
failure may experience worsening of their disease and
therefore should not take these medications. Thus far,
cancer rates have not been clearly shown to be increased in
RA patients taking TNF antagonists versus other RA patients,
but the data is somewhat confusing. Recently, the press has
publicized an increased rate of a cancer known as lymphoma
in patients taking these medications, but this was compared
to the normal population. Because RA patients as a
whole have an increased risk of lymphoma, it is not clear if
the medications themselves or the disease accounts
for this increased rate.
On the whole, we have found these medications
to be well worth the cost and the potential side effects and
have seen them virtually eliminate signs of active disease
in patients resistant to many of our standard therapies.
Currently, we are using TNF antagonists mostly in patients
who have inadequately responded to MTX or other therapies.
Most often, these drugs are added to MTX and may be more
effective when used in this manner but may also be used
alone. Use of TNF antagonists earlier in the course of the
disease is being investigated and may be recommended for
certain patients in the future. Despite the efficacy of
these medications, there remains a subset of patients (about
30% in most studies) who respond inadequately to each of the
TNF antagonist drugs. Switching to a different TNF
antagonist is often effective in such patients, although
some physicians prefer to use another biologic drug with a
different mechanism of action, and these medications will be
discussed further.
Abatacept (Orencia) is a biologic DMARD
that works to block the activation of a subset of white
blood cells known at T-lymphocytes, cells that are involved
in causing joint inflammation in RA. Orencia is given
intravenously every 4 weeks, but while this drug requires
more frequent administration than Remicade, the infusion
time is typically no longer than one hour, about half the
time it would take to administer Remicade. This drug is
typically given in combination with MTX. Not only has
Orencia been shown to be effective in patients responding
inadequately to traditional DMARDs, it also may be effective
in patients with a less than ideal response to TNF
antagonists. Like TNF antagonists, this drug appears to
significantly slow joint damage by x-rays as well. The onset
of action for Orencia is often more delayed than what is
noted for TNF antagonist medications and may not be observed
for several months after starting the drug.
Like TNF antagonists, Orencia is associated
with an increased risk for infections, and careful
observation is again warranted in patients receiving this
drug. Infusion reactions, while less commonly seen than with
other biologic drugs, can also occur with Orencia. Finally,
a few studies have raised the concern that patients with
chronic obstructive pulmonary disease (COPD, or emphysema)
may experience worsening of symptoms, and caution should be
exercised when using this drug in patients with this
illness.
Rituximab (Rituxan) is an antibody against
another type of white blood cell known as B-lymphocytes,
which also have a role in generating inflammation in the
joints of patients with RA. This drug was originally
developed for the treatment of lymphoma, or a tumor of the
lymph nodes, but has been adapted to the treatment of RA and
is being investigated for use in other autoimmune diseases.
While also given intravenously, Rituxan only needs to be
administered in two sets of infusions every 6 months, with
each set of infusions being two weeks apart. Each infusion,
however, requires 4-6 hours to complete. The onset of action
for Rituxan, as with Orencia, is typically not seen for
several months after the initial infusion but may actually
increase with subsequent rounds of infusions. The majority
of patients taking Rituxan, as with other biologic drugs,
continue to use concurrent MTX therapy. Like other biologic
drugs, Rituxan both reduces signs and symptoms of the
disease and appears to significantly slow joint damage. With
continued use of Rituxan some patients can be maintained
with longer intervals between sets of infusions than the
typical 6 months. Under current Food and Drug Administration
(FDA) guidelines, Rituxan can only be prescribed when
another biologic drug has failed to produce an adequate
response or if side effects have developed to that drug.
Infusion reactions may also occur with Rituxan
but are typically less frequent and less severe when the
drug is used for the treatment of RA than when it is used to
treat patients with lymphoma. Infections occur more
frequently in Rituxan treated patients, and vaccinations
given after the administration of this drug may have less
protective effect due to the suppression of the normal
immune response. A rare and fatal infection of the brain
known as progressive multifocal leukoencephalopathy (PML)
has been described in isolated patients treated with Rituxan,
predominantly in patients treated with this drug for
illnesses other than RA and when used in combination with
other immunosuppressive drugs. It is noteworthy that this
complication had also been reported in the setting of
autoimmune diseases prior to the introduction of Rituxan as
well.
Tocilizumab (Actemra), is the most
recently approved biologic drug for the treatment of RA and
is targeted against interleukin-6 (IL-6), another chemical
playing a central role in the inflammation of RA. Like
Orencia, Actemra is given as an intravenous infusion every 4
weeks, and the response may be fairly rapid in many patients
initiating therapy. Actemra has been well studied in early
RA, in MTX inadequate responders, and in patients
experiencing and inadequate response to TNF antagonists and
it is effective in all of these settings. This agent may be
used alone but is more often given in combination with MTX,
as with other biologic drugs, and it too appears not only to
improve disease activity but also to slow the progression of
joint damage.
Like other biologic drugs, Actemra is
associated with an increased risk for infection and some
potential for infusion reactions. In addition, suppression
of white blood cell counts, elevation of liver enzymes, and
an increase in cholesterol levels have all been observed in
some patients treated with Actemra. With proper monitoring,
problems with white blood cells and liver enzymes can be
minimized, and the significance of the elevated cholesterol
levels is not yet known, since there is also an elevation of
the HDL (so-called "good cholesterol"), which may balance
out any possible negative effects of cholesterol elevation.
Monitoring of cholesterol levels while on therapy with
Actemra is prudent.
Anakinra (Kineret) is an injectable drug
given once daily and inhibits a substance know as
interleukin-1 (IL-1). While effective in a subset of RA
patients, responses to therapy are generally less dramatic
that those seen with TNF antagonists. A somewhat increased
infection rate and injection site reactions are the most
commonly observed side effects.