Latest advice on diagnosing and managing fibromyalgia
ired all the time and 'pain all over' are common complaints in primary care. Fibromyalgia is a common explanation for both when their impact is great.
Fibromyalgia is chronic widespread musculoskeletal pain associated with pain on thumb pressure examination at multiple tender points. It leads to high disability rates from pain and fatigue. There are no good UK studies of how common fibromyalgia is, but studies from Germany and North America find a prevalence of 2 per cent and commoner in women than men1,2.
Is fibromyalgia a 'real' condition?
Its existence is not universally recognised by rheumatologists or the law courts. Diagnosis is self-fulfilling: everyone with widespread pain and tenderness has it and despite over 20 years' intensive research there is no commonly agreed cause.
But there is an increasing weight of evidence to show consistent abnormalities in the central nervous system related to pain processing such as increased levels of substance P3 in the cerebrospinal fluid and areas of reduced cerebral perfusion on functional MRI scans.
What are the diagnostic criteria?
Diagnosis is made using the 1990 American College of Rheumatology classification criteria4. An individual must complain of widespread pain for more than three months and pain on thumb pressure examination (pressure required to make the thumb nail blanch) at at least 11 out of 18 tender points (see figures and tables).
Assessment of chronic widespread pain
Patients need to be listened to and feel health professionals believe them. Striving for recognition of their illness as genuine is the main initial aim of sufferers. Once this is achieved patients can be engaged in an agreed treatment plan.
Besides complaints of pain in various parts of the body, other commonly associated features help to positively identify the condition.
These include waking unrefreshed in the morning; poor memory; poor concentration; pain worse the day after increased physical activity; irritable bowel symptoms; sensitivity to bright light, loud noise, alcohol and medication side-effects.
Thorough physical examination helps engagement and to rule out serious pathology. Investigations can usually be limited to a full blood count (to rule out anaemia or leukaemia), acute phase response (ESR or CRP to exclude significant inflammation or major infection), renal, liver, bone and thyroid profiles and glucose measurement.
Repeat or further investigation or referral for any specific symptoms such as headache, chest pain or gastrointestinal symptoms is unlikely to be productive.
Areas of controversy
There are many non-evidence-based ideas about the cause of fibromyalgia. These are freely available uncensored through the internet and many patients will find them.
Patients may feel they are the expert and become frustrated the information they believe is not widely known. This may undermine the doctor-patient relationship. It can be difficult in a consultation to explain how non-evidence based the plausible explanations are and reassure patients. These proposed causes include:
lmultiple endocrine deficiencies including 'undiagnosable' thyroid deficiency
lstiff red cells
la build-up of phosphate in the muscles (treated with an antitussive guaifenesin).
How to treat fibromyalgia
Sufferers of pain often have their own ideas about the cause. These are worth understanding to enable engagement in treatment. There are good patient information leaflets summarising what fibromyalgia is and how it can be treated. Expert patient programmes can teach generic patient self-management skills such as pacing activities and taking rest, pain management, and how exercise has beneficial effects.
· Graded exercise
There are now several randomised controlled trials that show the benefit of graded exercise. These can be maximised by a supportive environment, keeping the exercise low impact and starting at a very low level and increasing it as the patient tolerates it.
Unfortunately some of the gained benefits are soon lost when the interventions are finished. Such programmes are readily available through most exercise referral schemes.
Randomised controlled trials show benefit from monotherapy with amitriptyline or flexible dosing of fluoxetine and for the combination of amitriptyline with fluoxetine5, 6, 7.
Amitriptyline and fluoxetine should be started separately and at the lowest possible dose as intolerance due to side-effects are common.
Start amitriptyline at 2.5-5mg in the evening two to four hours before bedtime to avoid a 'hangover' the next day. It can be increased as tolerated at weekly intervals with the commonest doses being 10-50mg an evening.
Fluoxetine should be started at 10-20mg in the morning. The dose can be increased at weekly intervals to 40mg then 60mg and if tolerated 80mg.
The commonest maintenance dose is 60mg. One study shows the
combination of amitriptyline 25mg and fluoxetine 20mg. is better than either separately6.
· Cognitive behaviour therapy
Small studies show significant benefit in pain, fatigue and sleeplessness; and improved function, mood state, and general health8. It may be these benefits could be obtained through expert patient programmes. Lack of access and availability of CBT limits its use in chronic pain.
Fibromyalgia can exist on its own, but almost all patients will simultaneously fulfil the diagnostic criteria for chronic fatigue syndrome. Concomitant mental health problems are frequent
present in a third to a half of patients (most commonly anxiety and depression).
Fibromyalgia is also more common in many medical conditions including lupus, inflammatory bowel disease and rheumatoid arthritis.
In such conditions it is called 'concomitant fibromyalgia'. It can develop from localised musculoskeletal pain: this is best recognised as a sequel to whiplash injuries: 'post-traumatic fibromyalgia'.
Explaining the illness to patients
One approach is to point out the absence of serious pathology and explain the illness in terms of central sensitisation that is to say, the brain is sensitised to normal sensations as unpleasant or painful.
There are several ways this might manifest: normal bodily sensations are perceived as unpleasant such as moderate pressure on the tender points, and intestinal contractions may be painful (irritable bowel).
External sensations can also be unpleasant. Patients are often sensitive to bright lights so they may wear tinted glasses. Loud noises, gregarious company and alcohol can be unpleasant. Any internal disease process such as organic muscle disease, hormone or immunological disturbance would be
hard pressed to cause these symptoms directly.
Therefore their prescence does not mean harm is being done. Worries about the cause of the symptoms can be allayed and individuals learn to move away from activity guided by symptoms to activity despite them.
Flare-ups are usually caused by over-activity when having a good day. Learning to pace activities and rest leads to consistent activity without relapse and allows slow increases in activity.