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        Fibromyalgia -- A Physician's Guide   David A. Nye MD, 14Dec96


        Fibromyalgia syndrome (FMS) is an underdiagnosed disorder of
        unknown etiology affecting over 5% of the patients in a general
        medical practice (Campbell 1983) and an estimated 2-4% of the
        general population (Wolfe 1993), women more often than men.
        Patients complain that they ache all over.  A large number of
        other symptoms are often present, particularly fatigue, morning
        stiffness, sleep disturbance, paresthesias, and headaches (see
        table 2).  On examination, areas of focal tenderness called
        tender points can be demonstrated in characteristic locations
        (table 3).  Most patients can be helped substantially with
        treatment.


    Etiology

        A comprehensive review of the many theories of the etiology of
        FMS is beyond the scope of this paper.  While there is still
        not a majority of FMS researchers who support any one theory,
        significant progress is being made in identifying an etiology,
        and much useful evidence has been collected.

        FMS was first described as an inflammatory condition (Gowers
        1904).  When no evidence of inflammation could be found and an
        association was noted with depression and stress, the concept
        of "psychogenic rheumatism" was advanced (Boland 1947), but a
        number of studies have established that FMS is neither a
        psychosomatic nor somatiform disorder and that when present,
        anxiety and depression are more likely to be the result than
        the cause of FMS (Goldenberg 1989, Yunus 1991, Dunne 1995).

        It has been suggested that the pain of FMS is related to
        microtrauma in deconditioned muscles and that exercise works by
        conditioning these muscles (Bennett 1989).  However, reports of
        muscle biopsy abnormalities other than disuse atrophy have been
        difficult to replicate (Schroder 1993), and some tender points
        are not over muscles or tendons, such as the one over the
        medial fat pad of the knee (Smythe 1989).  Muscle energy
        metabolism is normal in FMS (Simms 1994, Vestergaard-Poulsen
        1995).

        FMS may be due to non-restorative deep sleep (Moldofsky 1975,
        1993).  Patients with FMS often report insomnia or light sleep
        as well as an increase in FMS symptoms after disturbed sleep
        (Campbell 1983).  Abnormal amounts of alpha activity on the
        electroencephalogram of FMS patients during deep sleep have
        been reported (Hauri 1973, Moldofsky 1975).  FMS-like symptoms
        can be induced in normal volunteers by depriving them of deep
        sleep, except in subjects who exercise regularly (Moldofsky
        1975).  Controlled trials have confirmed the value of aerobic
        exercise in the treatment of FMS (McCain 1988).  Exercise
        increases time spent in deep sleep (Hobson 1968), perhaps the
        mechanism for its therapeutic effect.

        A number of changes in immune system function have been found
        in FMS, generally in the direction of increased activity, many
        of which can also be induced in normal volunteers through sleep
        deprivation (Moldofsky 1993).  Many of the symptoms of FMS
        may be caused by elevations, induced by abnormal sleep, in
        certain cytokines such as interleukin-2, which has been found
        to be elevated in FMS patients, and which causes FMS-like
        symptoms when given intravenously (Wallace 1990, Moldofsky
        1995).

        Serotonin appears to be important in FMS.  Serum levels of
        serotonin and its dietary precursor tryptophan are low in FMS
        (Russell 1996).  Amitriptyline, one of the medications often
        used to treat FMS (see below), blocks serotonin reuptake and
        increases deep sleep (Baldessarini 1985).  Serotonin is
        important in deep sleep and in central and peripheral pain
        mechanisms (Chase 1973).

        The concentration of substance P, a peripheral pain neuro-
        transmitter, is several times higher in the cerebrospinal fluid
        of FMS patients than in pain-free controls, implying a
        peripheral origin for FMS pain (Russell 1994).  A number of
        other neuroendocrine abnormalities have been identified in FMS
        patients (Crofford 1994, Moldofsky 1995, Russell 1996) which
        form the basis for other theories of the etiology of FMS.

        Although no specific inheritance pattern has been identified,
        an increased incidence in relatives of affected patients has
        been noted (Pellegrino 1989).  Development of the syndrome may
        require a predisposing factor, possibly inherited, as well as a
        precipitating factor such as trauma, infection, stress, or
        sleep disruption.  The immunologic abnormalities suggest an
        infectious etiology, but if FMS were infectious we would expect
        to see an increased incidence in spouses of an affected patient
        and not just in their children and this is not the case.

    Diagnosis

        Since FMS is a syndromic diagnosis, any patient who fits the
        diagnostic criteria of chronic, diffuse aching with tenderness
        in at least 11 of 18 characteristic locations (Table 3) has it
        by definition.  It is not possible to accurately diagnose FMS
        without knowing how to do a tender point examination.  It
        cannot be accurately diagnosed by exclusion.  One would expect
        medical students to have been taught in physical diagnosis how
        to examine for a disorder that accounts for more than 5% of a
        primary care practice but lamentably this is not yet the case
        in most medical schools.  If a patient has typical symptoms of
        FMS (Table 2) but does not meet the tender point criterion, a
        diagnosis of "possible FMS" may be assigned and a therapeutic
        trial of standard treatment offered.  Tender points should be
        looked for again on a return visit as they may be more evident
        on some days than others.

        Although there have been many abnormalities of laboratory and
        other tests reported in FMS, none is sufficiently sensitive nor
        specific to be useful diagnostically, so routine studies are
        not recommended.  Patients who haven't recently had a general
        medical evaluation should as part of the workup, and other
        tests should be ordered when the history or exam raises a
        question of something other than FMS.  In older patients a
        sedimentation rate may be useful to exclude polymyalgia
        rheumatica.  In patients with other symptoms of hypothyroidism,
        thyroid studies may be indicated.

        The current syndrome definition may not be the best one
        possible (Wolfe 1993).  It has been argued that tender points
        have been over-emphasized, probably because historically
        rheumatologists have been more involved in the diagnosis and
        treatment of FMS than other specialists.  In many patients who
        meet the criteria for diagnosis for chronic fatigue syndrome,
        the only difference between them and a typical FMS patient is
        the degree of pain.  Some of these patients followed over time
        will subsequently develop tender points and then fit the
        criteria for diagnosis of FMS.  70% of patients with FMS meet
        the CDC criteria for CFS (Buchwald 1987) and two thirds of
        patients with CFS meet the ACR criteria for FMS (Goldenberg
        1990b).  It seems unlikely that these patients have two
        separate disease processes.  Perhaps dividing these two groups
        of patients on the basis of whether or not they have prominent
        pain is as artificial as division on the basis of prominence of
        any of the other twenty or so associated symptoms.

        On the other hand, we are to some extent stuck with the current
        syndrome definition because it is these patients on whom all
        the important studies have been performed.  If the syndrome
        definition is altered, we can't be certain that all of these
        results still apply to the new syndrome.  This problem will
        disappear once we know the true etiology and can make an
        etiologic rather than syndromic diagnosis.


    Treatment

        Controlled studies have shown that amitriptyline (Goldenberg
        1986, Jaeschke 1991), cyclobenzaprine (Quimby 1989), alprazolam
        (Russell 1991), aerobic exercise (McCain 1988), and other
        interventions to be discussed later are of benefit in treating
        FMS, but the percentage of patients responding to each alone is
        small.  When gentle daily aerobic exercise, a consistent bed
        time with adequate amounts of sleep, and one of several
        medications to improve deep sleep are combined, as expected
        more patients improve.  This approach has not yet been studied
        rigorously, but in a retrospective chart review I found that 30
        of 36 patients (83%) had improved substantially with it, many
        of those to the point of having no aching most of the time.
        Trazodone, diphenhydramine, carisoprodol, and doxepin have
        similar effects on deep sleep and are also widely prescribed
        for sleep in FMS, but have not yet been studied in controlled
        blinded trials.  Cyclobenzaprine and diphenhydramine are
        pregnancy category B and thus preferable in women who are or
        are attempting to become pregnant.  Alprazolam is pregnancy
        category D and so should be avoided in these patients.

        Medications effective in the treatment of FMS appear to work
        mainly through an effect on deep sleep (Goldenberg 1986).  They
        should be started at the lowest possible dose and increased
        every few days to a week to maximum relief of daytime FMS
        symptoms without unacceptable side effects.  I allow patients
        to fine-tune the dose themselves.  The starting doses and
        ranges of several medications useful in the treatment of FMS
        are listed in Table 1 in roughly the order I tend to try them.
        Amitriptyline is an effective medication for FMS but it has
        frequent daytime side effects attributable to its long half
        life such as weight gain, dry mouth, and cognitive impairment.
        I usually start with shorter-acting medications which help
        sleep and are gone during the day.

        It is often necessary to try several different medications in
        succession and sometimes in combination before finding a
        regimen that works well.  Some tolerance often develops to the
        sedative effect of many of these, necessitating one or two dose
        increases after an initial good response to maintain efficacy.
        When switching from one medication to another, it is important
        to taper the first slowly as the second is increased to try to
        maintain sleep quality and avoid exacerbating FMS symptoms.

        Imipramine, steroids, and non-steroidal anti-inflammatory drugs
        (NSAIDs) have all been found to be no better than placebo
        (Goldenberg 1993).  While NSAIDs might be expected to be
        helpful if only for the analgesic effect, their tendency to
        cause some insomnia may cancel out the expected benefit.
        Narcotics and benzodiazepines other than alprazolam block stage
        4 sleep and so should be avoided.  While they may help
        symptomatically, they often make the patient feel worse the
        next day and may prevent her from ever being able to get to the
        point of being pain-free most of the time.  Tramadol and
        acetaminophen do not seem to interfere with sleep and are
        therefore a better choice for analgesia.

        Fluoxetine was found in one study to be ineffective except to
        symptomatically treat associated depression (Wolfe, 1994).  A
        second study found it effective in combination with
        amitriptyline (Goldenberg 1996), but this may have been because
        fluoxetine increases amitriptyline levels which weren't
        monitored.  A second serotonin re-uptake inhibitor, citalopram,
        was ineffective for FMS symptoms (Nxrregaard 1995).

        There are many other unstudied "alternative" drug and herbal
        treatments, some of which may in the future be proven effective
        in controlled studies.  I do not recommend these since they are
        as yet unproven scientifically and may have unrecognized
        toxicities, but I have given up trying to dissuade patients
        from trying them as long as it is not in place of conventional
        therapy.

        Daily, gentle, low-impact aerobic exercise helps (McCain 1988),
        but too much or the wrong kind of exercise may exacerbate FMS
        symptoms.  Patients who are deconditioned should start out with
        just 3-5 minutes of exercise every day and increase as
        tolerated, usually up to 20-30 minutes a day.  The benefit of
        the exercise seems to be from its systemic effects rather than
        any direct effect on the exercised muscles.  It works better if
        the patient avoids exercising the most painful muscles.

        Patients should try different ways of exercising to find the
        best kind for them.  Walking or bicycling outside or various
        kinds of home exercise equipment are the most popular.  Aerobic
        water exercise may be best tolerated because it eliminates
        weight-bearing, but it is hard for patients to get to a pool
        every day.  Water exercise can be useful to get patients
        started when they can't tolerate anything else.  Once their
        stamina improves, they should add another form of exercise on
        the days they don't swim.  Exercise is most effective if done
        in the late afternoon or early evening, perhaps because of its
        known effect on deep sleep.  A small percentage of patients can
        never get up to an effective amount of exercise, but without
        it, few will improve much in my experience.  Patients who have
        been exercising daily and then skip a day will usually complain
        of feeling worse for 2-3 days afterward, an experience which
        often helps convince them of the need for daily exercise.

        Getting adequate sleep is essential.  FMS symptoms often appear
        during times of sleep disruption (Saskin 1986) such as may be
        brought on by an injury or other pain, stress, shift work, or
        having to get up to attend to young children.  At times just
        re-establishing a regular sleep schedule may be enough to
        relieve symptoms.  I have not been able to get patients who
        swing shifts to improve substantially unless they can get onto
        shifts that allow them to sleep nights and keep a consistent
        bedtime.

        Other coexisting sleep disorders such as obstructive sleep
        apnea (OSA) and periodic limb movements of sleep must be
        identified and treated.  Not infrequently a spouse's snoring
        will exacerbate the patient's symptoms, in which case treating
        the spouse's snoring or having the patient wear ear plugs will
        help.  44% of men with FMS have been found to also have OSA
        (May 1993), a potentially life-threatening disorder which is
        important to treat in its own right.  It is important to take a
        sleep history in all patients with FMS, including asking the
        spouse about snoring, apneas, and movements at night.  In
        resistant FMS cases, referral to a sleep disorders center for
        polysomnography may be helpful.

        Patients must also be careful not to overdo physical activity.
        For example, once she is feeling better a FMS patient may try
        to catch up on housework she has been unable to do, but this
        may trigger a relapse that puts her in bed for several days.
        It is better to plan to spend a smaller amount of time every
        day at such activities until they are completed.  Patients must
        learn to sense when they have reached their limit and stop
        before they get into trouble.

        Other treatment modalities which have been shown in controlled
        studies to be helpful include EMG biofeedback (Ferraccioli
        1989), regional sympathetic blockade (Bengtsson 1988), and
        cognitive behavioral therapy (Goldenberg 1991).  Many patients
        report that gentle massage as well as heat and rest help.
        Some report that, as with migraine, certain foods appear to
        precipitate their symptoms.  Several patients have told me that
        their FMS symptoms improved significantly on a low-fat weight
        reduction diet started to lose the weight gained from taking
        amitriptyline.  Most patients do better if they give up
        caffeine and other stimulants entirely.  Alcohol should be
        avoided because of its tendency to suppress deep sleep.  This
        is usually not a problem because most FMS patients tolerate
        alcohol poorly to begin with.  Certain symptoms such as
        migraine headaches or depression can also be treated directly
        if treatment of the underlying disorder does not control them
        adequately.

        FMS and myofascial pain syndrome (MPS), while probably separate
        entities, often coexist (Granges 1993).  When they do, each
        needs to be treated separately.  MPS is associated with trigger
        points which should be distinguished from the tender points of
        FMS.  Trigger points are located over a band of taut muscle and
        cause pain that radiates away from the point of pressure.  MPS
        is usually treated with avoidance of activities which worsen
        it, myofascial release and other forms of physical therapy, and
        if necessary, trigger point injections or dry needling.

        Support and education are important.  Patients need to be
        actively involved in their treatment and to have as clear an
        understanding of this complicated disorder as possible.
        Patients often elicit less sympathy and support from family,
        friends, and employers than they deserve because of the lack of
        physical stigmata of disease.  By the time they get to see
        someone skilled in the management of FMS, many patients will
        have been told by at least one other physician that there is
        nothing wrong with them or that it is "all in your head" which
        can be quite demoralizing.  An understanding approach by the
        physician and the patient's participation in a well-run support
        group may have considerable therapeutic benefit.

        Education, frequent follow-up visits, and reassurance help to
        get patients over the first few weeks of treatment.  It may be
        difficult to convince patients to exercise when they experience
        fatigue and aching.  It often takes two weeks or more before
        the beneficial effects of medication and exercise outweigh
        their side effects.  Sometimes it takes several months of
        trying different medications in different combinations and
        adjusting doses before getting it right.  The physician should
        check on the amount and type of exercise and sleep at return
        visits and reinforce their importance.  Patients should be
        warned that despite optimum treatment and good initial results,
        brief relapses are common, often caused by temporary sleep
        disturbances.  The patient will do best if she "gives in to
        it", takes hot baths, and tries to get extra rest during a
        relapse.  A temporary increase in medication dose may also be
        necessary.

        A small number of patients continue to do poorly despite
        treatment.  Severely affected patients who can't be controlled
        otherwise (treatment failures) need to be involved in a chronic
        pain program, as outpatients or if necessary inpatients.  Some
        may need to apply for disability, which is harder to get for
        patients with FMS because of the lack of supporting physical or
        laboratory evidence, but guidelines are available (White 1995).
        With treatment however, the majority who were working can
        return to work although some may need to change jobs or get off
        shift work.  Most patients referred to me as treatment failures
        had not had an adequate trial of treatment.

    Conclusion

        FMS is a common, chronic, and if untreated, often disabling
        disorder of unknown etiology associated with neuroendocrine and
        immunologic changes and disordered deep sleep.  Most patients
        can be helped with a combination of medication, exercise, and
        maintenance of a regular sleep schedule.  Think of this
        condition in any patient with a complaint of aching and
        tiredness and look for associated symptoms and tender points to
        confirm the diagnosis.  The common misconceptions that FMS is a
        psychosomatic or somatoform disorder, is untreatable, is a
        diagnosis of exclusion or a "wastebasket" diagnosis, and that
        most FMS patients are hypochondriacs or whiners are unfounded.


        Table 1:  Some drugs useful in the treatment of FMS

        Drug name            Starting     Taken __ hrs  Usual maximum
                               dose (mgs)   before bed    dose (mgs)

          trazodone              50           0            600
          cyclobenzaprine        10           1             60
          alprazolam              0.5         .5-1           6
          carisoprodol          350           0-.5        1400
          diphenhydramine        50           .5-1         300
          5-hydroxytryptophan   100           1            600
          amitriptyline           5           2            300


        Table 2: Associated signs and symptoms (Wolfe 1990).

            widespread pain                         97.6% of patients
            tenderness in > 11/18 tender points     90.1
            fatigue                                 81.4
            morning stiffness                       77.0
            sleep disturbance                       74.6
            paresthesias                            62.8
            headache                                52.8
            anxiety                                 47.8
            dysmenorrhea history                    40.6
            sicca symptoms                          35.8
            prior depression                        31.5
            irritable bowel syndrome                29.6
            urinary urgency                         26.3
            Raynaud's phenomenon                    16.7

        Other commonly reported symptoms include dizziness, trouble
        with memory and concentration, rashes, and chronic itching
        (unpublished observations).


        Table 3: Location of tender points (Wolfe 1990).

            suboccipital muscle insertions at occiput
            lower cervical paraspinals
            trapezius at midpoint of the upper border
            supraspinatus at its origin above medial scapular spine
            2nd costochondral junction
            2 cm distal to lateral epicondyle in forearm
            upper outer quadrant of buttock
            greater trochanter
            knee just proximal to the medial joint line

        To meet ACR 1990 diagnostic criteria for fibromyalgia, digital
        palpation with an approximate force of 4 kgs. must produce a
        report of pain in at least 11 of these 18 tender points.  Other
        areas can be tender as well.  The tenderness should be focal
        rather than diffuse.  Tender points must be present on both
        sides of the body, above and below the waist and in the midline.
        Widespread pain must have been present for at least 3 months.
        Some accept a diagnosis of fibromyalgia with fewer than 11
        tender points if several associated symptoms from table 2 are
        also present (Wolfe 1989).


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