Fibromyalgia
References
Epidemiology
Common chronic widespread musculoskeletal pain
Women between 20 and 55 years
Prevalence 2 to 3 percent - increases with age
F>M = 6:1
Under diagnosed
Chronic widespread pain = 10 to 15% of population
Pathogenesis
Genetics
First degree relates = 8.5 more likely to have FM than relatives of patients with Rheumatoid Arthritis
Significant differences in alleles between FM and control
Serotonin and opioid pathways - SSRI SNRI improve symptoms
CNS altered pain processing
FM = greater than normal increases in perceived intensity of pain
Decreased endogenous analgesics
Changes in opioid receptors
Central hypersensitivity
Pathophysiologic Studies
FMRI = Greater neuronal uptake in pain processing pathways
Increased catastrophising
Brain morphology
Reduced total gray matter suggesting premature brain aging
Altered neurotransmitter function
Higher glutamine in posterior insula = lower pain thresholds
Deficits in GABAergic and Glutamergic mechanisms
Higher inositol in right amygdala and right thalamus
Low GABA in right insula
Sleep
Phasic alpha sleep
Suggestions that sleep disturbance precedes FM development
Study Norway Women = Sleep disturbance = RR 3.3 of developing FM
Stress HPAA
Correlation with cortisol and pain on waking in FM vs control
Peripheral Pain Mechanisms
Small fibre neuropathy
Immune Abnormalities
Different cytokines
Not pro or anti-inflammatory
Clinical
Fatigue
Cognitive Disturbance
Psychiatric symptoms
Somatic symptoms
Symptoms
Widespread MSK pain
At least 6 sites from this figure - AAPT Diagnostic criteria
Fatigue and sleep disturbance
Moderate to severe
Minor activities aggravate pain and fatigue
Prolonged inactivity heightens symptoms
Stiff in the morning
Sleep
Unrefreshed despite 8 to 10 hours
Sleep light
Wake frequently
Difficulty getting back to sleep
Cognition
Brain fog
Difficulty with attention and tasks requiring rapid thought change
Psychiatric
Anxiety / Depression in 30 to 50% of patients
30% had a lifetime history of Bipolar, Panic Disorder or PTSD
Headache
50% including migraine and TTH
Paraesthesia
Numbness, tingling, burning, creeping, crawling in both arms and legs
NCS usually normal
Sensation of leg oedema without objective findings = small fibre neuropathy
Other
Variety of poorly understood pain
Chest wall
Abdominal
IBS symptoms
Pelvic pain
Bladder pain and frequency
Reflux
Autonomic dysfunction
Dry eyes (1.4x more common in FM)
Raynaud’s Phenomenon
Orthostatic hypotension
Hearing loss (4-5x more reported in FM)
Weather changes may aggravate symptoms
Environmental hypersensitivity
Lights and sounds
Examination
Universal findings is tenderness
Often marked
Modest palpation
Multiple soft tissue sites
Particularly sites listed in ACT Classification Crtieria
Neuro exam can reveal minor sensory or motor abnormalities
Tests
No changes
FBC, ESR, CRP = normal
Some changes noted on functional MRI scans
Skin biopsy can show small-fibre neuropathy
Diagnosis
ACR - Preliminary Diagnostic Crtieria for FM - 2010
History
Widespread pain
> 3 months
Fatigue, sleep disturbances
Other symptoms such as cognitive disturbance, headaches, bowel irritability
Physical
Widesprad tenderness
Absence of joint swelling and inflammation
Investigations
Normal FBC, ESR, CRP
Normal CK + TFT if indicated
Differential
Inflammatory Arthritis
ANA, RF
Non-inflammatory arthritis
Localised pain syndromes
Thyroid disease
TFT
Inflammatory and metabolic myopathies
CK
Statin myopathy
Myalgias
Infections
HIV, Hep, Chik, Long COVID
Endocrine
Cushings’s
Addisons
Neuro
MS and MG
Myofascial pain syndrome
CRPS
Work up
FBC, ESR,CRP
Additional evaluation
Sleep study if history of OSA or RLS or PLMD
Work up psychiatric diagnoses
Co-existing Disorders
Functional Somatic Syndromes and Related Disorders
30 to 70%
IBS
CFS
20 to 50%
Migraines / TTH
Chronic bladder and pelvic pain syndromes
TMJ disorders
Psychiatric
Anxiety, Depression (50%)
PTSD
Personality disorder (13%)
Sexual dysfunction (50%)
Bipolar (15%)
Sleep Disorders
Sleep disturbances common
Non-specific stage 4 sleep disturbance
Lower sleep quality and sleep efficiency
OSA, RLS and PLMD
Inflammatory Arthritis
RA
SLE
Sjogren’s
OA
Psoriatic arthritis
Management
Individualised approach
Prominent symptoms including pain, fatigue, sleep, depression
Past experiencing with or contrindiciations to medications
Comorbid conditions
Levels of physical fitness and barriers to exercise
Social determinants
Finances
Explanation
No persistent tissue damage or infection
Central pain
Nociception (peripheral pain) can be caused by inflammation or tissue damage
Nociplastic (central pain) results from issue with processing pain signals in the brain and spine
Fibromyalgia is a central pain syndrome
Widespread hypersensitivity
Lower threshold to pain
Like a guitar amplifier exaggerating the sound of a normal guitar
Pain is bidirectional
Local pain can aggravate FM and vice versa
Realistic expectations
Discuss concrete, achievable, short and long-term goals
Goals related to meaningful tasks in patient’s lives
Goals that are measurable and important
e.g. Number of times per week they can do a particular activity
No drug cure or highly effective treatment
Multimodal approach to make incremental improves in life
Symptoms wax and wane
Goals of FM treatment
Reduce major symptoms
Increase self-efficacy
Tailored medication and non-medication strategies
Treat comorbid disorders
Initial treatment algo
Core non-drug treatments
Education
Psychological therapy
Increased activity and exercise
Education
Explanation
Central pain
Not inflammatory
Not damage
Limited role drugs
Treat co-morbid = Important
Bi-directional relationship
Pain > depression > pain
Sleep disturbance
Common
Sleep in a dark, quiet, cool room
Avoid stimulants
Blue light
Caffeine
Social media
Alcohol
Avoid adverse factors
Disruptive pets
Co-Sleepers
Medical conditions
Physical activity
Benefit from various forms of exercise
Cardiovascular training
Resistance training
Movement therapies such as Tai Chi
Exercise may increase physical function and restorative sleep
May improve pain and fatigue
Always include low-impact aerobic exercise
Individualise therapy
Current level of activity and tolerance
Co-morbid
Optimal cardiovascular fitness
30 minutes of aerobic exercise three times a week
Patients may not achieve but encouraged to exercise regularly at what level they can
Most evidence
Low-impact aerobic exercise and strength training
Cognitive Therapy
CBT
Mindfulness-based stress reduction
Meditation and / or relaxation
Medication
Start when moderate to severe symptoms
TCA - Endep
SNRI - Cymbalta
Alpha-2-ligants - Pregabalin
Endep / Amitryptiline
Diffuse, widespread pain without major mood disturbance or sleep issues
Start at 5 to 10 taken 1 to 3 hours before bedtime
Increase by no more than 5mg every 2 weeks
Use the lowest dose possible, generally between 20 and 30mg
Continue lowest dose that achieves a response for at least 12 months
Can stay on indefinitely or wean
Side effects: anticholinergic effects (eg, dry mouth, constipation, urinary retention), central nervous system (CNS) depression (eg, drowsiness, confusion, fatigue), serotonin syndrome, cardiac conduction abnormalities, increased bleeding, hyponatremia, fluid retention, and weight gain.
Improvement in 25 to 45 % of patients
Cymbalta / Duloxetine
Severe fatigue and/or depression
Start at 20 to 30mg in the morning with food
Increase by 20mg every few weeks to 60mg daily as toelrated
Doses as low as 20 to 30mg can be effective
Side effects - Potential adverse effects of SNRIs include hepatotoxicity, bleeding, fragility fractures, hyponatremia, orthostatic hypotension, and serotonin syndrome. Patients may also experience withdrawal symptoms, such as fatigue, anxiety, and insomnia, either with gradual or abrupt discontinuation, usually within 1 to 10 days of stopping.
Improvement by reducing pain by 50%
Side effects lead to stopping medication in 12%
Pregabalin / Lyrica
Prominent sleep disturbance
Start at 25 to 50mg at bedtdime
Increase by 25mg to 50mg every 2 to 4 weeks
Up to 300 to 450mg daily in 1 or 2 divided doses as tolerated
Side effects - Potential adverse effects of pregabalin include CNS and respiratory depression, dizziness, blurred vision, peripheral oedema, weight gain, and suicidal ideation.
Effect - 10% reduction in pain
Medication efficacy
At best, modestly effective in less than 50 percent of patients
One study showed 50% of patient continued medication for more than 20% of the year
All were effective for pain
Similar effects for sleep, depression and fatigue
Endep most improvement QoL
Combination
Low dose Cymbalta AM = 30mg + Low dose Endep nocte = 10 to 20mg OR Lyrica at night
Other Medications
SSRI
Analgesia
NSAID
Low Dose Naltrexone
Thought to enhance endogenous opioid system
Options for 2nd or 3rd line option
Nutrition and Diet
BMI correlates with developing FM and severity of symptoms
Caloric restriction and weight loss may improve FM symptoms
Study of 123 obest FM patients, 12 weeks on 3500kJ diet,
Improvement in symptoms severity, pain and depression
Effect more noticable in those that lost 10% BW
Follow up study showed improvement by 3 weeks despite no weight loss
Some diets including plant based seem to improve symptoms
Other treatments
Acupuncture has been show to improve FM
Massage and manual therapy can help
TENS = mixed results
rTMS = possible reduction in depression and fatigue
Prognosis
Study of 500 patients in hospital setting
Pain, fatigue, sleep disturbance and depression were unchangedo ver 8 years
2/3 reported working full time and FM only interfered modestly with their lives
PsA vs Fibro
Podcast - Link
Management
Address sleep patterns
Avoid screen time
Bedroom cool and dark and quiet
Medication
Amitryptiline
Aerobic exercise
Walking 15 to 30 minutes absolutely every day
Changes abnormal neural pathways that cause fibromyalgia
Stretching programs
Medication
Endep
SNRI / Cymbalta
Allows more NA / Serotonin
Suppresses pain pathways
No narcotics - make things worse
Physiotherapy
Stretching
Relaxation exercise
Psychologist
CBT
Stress reduction
Meditation