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Introduction:
A controversial, elusive condition,
FM affects about 2% of the United States population and is
about 7 times more common in women than in men. While many
question the existence of this disorder, FM clearly describes
a group of individuals with chronic muscle tenderness and
disturbed sleep patterns commonly seen in the general
population.
While a subset of these patients may also have inflammatory
diseases such as lupus or rheumatoid arthritis, FM itself is
not associated with joint or muscle damage, inflammation,
laboratory abnormalities, or x-ray changes. So what exactly
is FM? Most investigators now feel that the basic
problem is a problem with the way pain is processed in the
brain. Imaging studies such as positron emission tomography
(PET) scans show changes in blood flow in certain parts of the
brain in FM. Moreover, patterns of hormones produced in the
brain are abnormal in FM, and levels of a chemical called
substance P known to be involved in pain are elevated in
spinal fluid samples of FM patients. In other words, people
with FM are �wired� differently.
No one knows what causes FM. While there are theories about
infections, injuries, stressful events, and genetic influences
being involved, none of these possibilities have been proven.
Because about 2/3 of FM patients are depressed, many have
attempted to suggest that this condition is simply a
manifestation of depression. The problem with this
explanation is that is does not take into account the 1/3 of
patients who are not depressed or the fact that of those with
FM and depression, about 1/2 were depressed before they
developed FM symptoms, and 1/2 developed depression after the
onset of FM.
Features of
FM:
The major symptoms of FM are difficult to measure and rely
solely on the patient�s self-report. Widespread muscular
pain, disturbed sleep, and fatigue are the major
manifestations present in FM patients.
The muscles
are often tender to light or moderate pressure that would
ordinarily not produce discomfort. While many of these
muscles may feel tense, there are no other observable
abnormalities on physical examination. Many individuals with
FM will report a sensation of swelling in the hands, but
unless another condition is present along with FM, the joints
themselves should not be swollen when examined by an
experienced physician.
Sleep patterns
in FM patients are typically abnormal. The pattern of brain
waves, when measured in sleep labs, is impaired during the
deep stages of sleep. As a result, most people with FM
describe their sleep as not being refreshing. Frequent
awakenings throughout the night are common. It has been
reported that normal subjects who are studied in sleep labs
will also experience muscle tenderness when their sleep is
interrupted, suggesting that this problem is key to the
development of FM.
Fatigue is a
complicated issue and has many potential causes. Sleep
deprivation, depression, lifestyle, and other unrelated
problems such as anemia, thyroid disease, or inflammatory
conditions can all contribute to fatigue. As such, this is a
very difficult symptom to address but one that is experienced
by the vast majority of patients with FM.
Other
associated conditions include chronic tension headaches,
irritable bowel syndrome, and chronic fatigue syndrome. Up to
25% of patients with systemic lupus erythematosus (SLE) and
15% of patients with Sj�gren�s syndrome (SS) (see sections
on these conditions) also exhibit features of FM, but the
vast majority of patients simply have FM without an associated
inflammatory illness.
Diagnosis:
As mentioned above, there are no
laboratory or x-ray tests that aid physicians in making the
diagnosis of FM. In some patients, however, it may be
necessary to perform some of these studies to rule out another
potential diagnosis that could mimic FM, such as SLE, SS,
rheumatoid arthritis, polymyalgia rheumatica, thyroid disease,
or a number of other conditions. For the most part, however,
these illnesses can be excluded by a careful interview and
physical examination.
Criteria for
diagnosing FM are based on the finding of > 11 of 18
tender muscle groups known as �tender points.� Most of these
tender points are located in the shoulder, neck, and
hip/buttock region. The presence or absence of these tender
muscles may vary from day to day but are often quite
reproducible. If a patient demonstrates a sufficient number
of tender points above and below the waist without tenderness
over �control points� (muscles that aren�t supposed to be
tender) and with the typical sleep disturbance, a diagnosis of
FM can be confirmed.
Treatment:
Despite the best efforts of
physicians caring for individuals with this disorder both in
office and research settings, definitive therapy for FM is
unfortunately lacking. Many well-intentioned health care
providers, desperately attempting to provide relief for FM
patients, find themselves tempted to either add a new
medication or increase the dose of an existing medication when
patients continue to experience symptoms. This may result in
increasing medication costs and side effects in exchange for
minimum benefit. Most patients seem to achieve the best
results with a combination of medical therapy, exercise, and
attention to �sleep hygiene.�
Medications useful in
treating many of the symptoms of FM include tricyclic
antidepressants such as amitriptyline (Elavil) and muscle
relaxants such as cyclobenzaprine (Flexeril), either of which
can be given at bedtime in attempt to restore restful sleep.
Other medications that may prove effective in different
patients include trazodone (Desyrel), fluoxetine (Prozac),
venlafaxine (Effexor), and a new medication that has shown
promise in recent trials known as duloxetine (Cymbalta).
While many of these medications are classified as
antidepressants, they appear to offer some benefit to patients
to FM patients who are not depressed as well by restoring
restful sleep and reducing muscle tenderness.
Analgesics such as tramodol (Ultram), sedatives such as
diazepam (Valium), and seizure medications such as gabapentin
(Neurontin) are also variably utilized to reduce FM symptoms,
but the evidence for benefit is not as well documented.
Non-steroidal anti-inflammatory drugs (NSAIDs) and
corticosteroids do not seem to have a role in the management
of FM. The issue of using narcotic analgesics, or opioids, to
treat FM is controversial. While such therapies are commonly
utilized, there has never been a well-designed study that
demonstrates that these medications improve function or
quality of life in FM. Our experience observing FM patients
who pursue such therapies has been highly disappointing.
Trigger point injections into isolated tender muscles are
another treatment option widely employed to treat FM, but once
again well-designed studies providing evidence for benefit are
lacking. Nonetheless, a trial injection into an isolated
tender point is worth attempting but should not be repeated if
no benefit is observed.
Exercise has proven
benefits in the treatment of FM. While it may seem difficult
to exercise muscles that hurt or to exert effort when already
fatigued, aerobic exercise often reduces these symptoms if
carefully performed. The key principle is �start low, go
slow.� The activity should be reduced if symptoms worsen
after completion of the exercise. Low-impact exercises such
as water aerobics are preferable to simple flexibility
training or high-impact activities (basketball, e.g.) and have
been documented in studies to reduce sensitivity of tender
points. We have personally observed the best outcomes in FM
patients who pursue and continue a consistent regimen of
exercise.
Sleep must be a
priority for FM patients. Activities such as smoking and
consuming alcoholic or caffeinated beverages prior to bedtime
often further the sleep disturbance of FM and should be
avoided. A warm bath or reading a book before bedtime are
conducive to restful sleep, while television is often
counterproductive in assisting with restful sleep. If
possible, schedules should be arranged to allow for a solid 7
to 8 hours of sleep per night.
The role of the rheumatologist in FM is variable. Patient
outcomes are similar whether coordinated by a specialist or
primary care physician. A rheumatologist is often most useful
to confirm the diagnosis, rule out other disorders and make
treatment recommendations that the referring physician can
institute. Only a small proportion of FM patients benefit
from regular visits to a specialists� office. Because of the
limited medical treatments that have benefit in FM, the most
valuable player in the management of this condition is
ultimately the patient him/herself. |
