Multiple Sclerosis Flashcards
What is Multiple Sclerosis?
- Chronic inflammatory condition of the central nervous system, affecting both the brain and spinal cord, immunemediated
- Progressive demyelination of neurones in the brain, spinal cord and cranial nerves (Hubert, 2023)
- Common - 1.2/1000 in UK (Jarman & Vivekananda, 2021). Commonest disabling disease affecting young people (Dobson & Giovannini, 2019)
- Exact cause unknown but autoimmune – hypothesised to be a combination of genetic predisposition, environmental triggers and immune-mediated acute then chronic inflammation, followed by progressive degeneration (GP notebook, 2022)
Epidemiology
* Prevalence of MS is increasing worldwide since 2013, particularly in Europe (143/100,000)
* Much lower in Africa, Asia and SE Pacific – between 5 and 9/100,000 (but may be differences in diagnosis (Dx) rate, reporting etc) but UV link may explain
* Only rarely may occur in children (Walton et al, 2020)
* Women are twice as likely to have MS as men
* Typically presents aged 20-40, rare to diagnose in later life
* More common in white populations (Jarman & Vivekananda, 2021)
What is the pathophysiology of Multiple Sclerosis?
- Activated T lymphocytes cross the blood-brain barrier and attack neurones in CNS
- This causes a really strong inflammatory reaction with proinflammatory cytokines which attack and cause acute loss of myelin sheath in discrete areas known as plaques (2-10mm)
- Loss of myelin interferes with impulse conduction
- THEN Recovery and remyelination OR - eventually there will be secondary, permanent axonal damage when severe
- Larger areas of inflammation and demyelination (irreversible as body cannot recover)
- Progressive decline and disability, more diffuse areas affected
There are different types:
* Relapsing remitting (85%) RRMS
* Progressive (10-15%)
* Secondary progressive (67% of RRMS)
* Also clinically isolated syndrome - shows some inflammatory demyelination but not ‘attacks’ - a pre-MS state
What is a relapse:
* Start of new symptoms/worsening of preexisting symptoms
* Attributable to demyelinating disease
* Lasting >24 hours
* Preceded by improving or stable neurological status for >30 days from the previous relapse
* No infection, fever or other significant metabolic disturbance
* 75% of RR MS -> secondary progressive within 35 years
What causes or triggers MS?
Risk factors
* Infections, particularly symptomatic Epstein-Barr virus (twice the risk)
* Low vitamin D levels (UVB exposure and latitude gradient strongly associated with risk) and lack of sunlight exposure
* Environment (migrants from low risk areas remain at low risk but their children born in a high risk country are at high risk)
* Childhood obesity
* Smoking (~50%)
* Genetics (~1/8 have family history, ~60 genes)
What are the signs and symptoms of MS?
- Loss of bladder and bowel control
- Limb weakness or spasticity
- Gait and balance problems
- Paraesthesia or neuropathic pain
- Fatigue - most common sign
- Mood symptoms like depression
- Visual and sensory disturbances (blurred vision)
Prognosis
* People can live with the condition for a long time, mostly independently
* Later stages causes severe disability - 15 years to using walking aids, 25 years to wheelchair use
* Wide variation and unpredictable course
* Reduces life expectancy by 7 years on average
* Pregnancy can be a concern – not affected by MS itself but may require changes to drugs/management
What are the conventional diagnosis and treatments for MS?
**Diagnosis **
* No definitive test, mainly clinical (neurology Dx) and excluding other diseases. **Few other neurological diseases have relapsing-remitting symptoms **
* Requires 2+ attacks affecting different parts of the CNS – investigations are used to support evidence of this and exclude other causes
* MRI of brain and spinal cord is key -> typically shows multiple scattered plaques (oval lesions up to 2cm in diameter). Should not be diagnosed on this alone. Presence in spinal cord useful to differentiate from other diseases.
* May have long delay and based mainly on clinical symptoms and lack of other neurologic diagnostic criteria. MRI used for diagnosis and monitoring CNS lesions.
* Cerebrospinal fluid analysis can be used -> shows elevated protein, gamma globulin and lymphocyte levels
Treatment
* Immunomodulatory disease modifying drugs (e.g. beta-interferon) by injection which reduce relapse rates, development of CNS lesions and short term disability – typically after 2 significant relapses
* Oral disease modifying drugs also effective (but more side effects), mainly used in UK where other drugs not effective/tolerated
* Aggressive MS - immunomodulatory drugs and monoclonal antibodies
How can herbs/ holistic treatment help?
Other support (NICE, 2022)
* Pharmacological and non-pharmacological treatment of symptoms such as fatigue, memory problems, mobility problems, spasticity
* Exercise encouraged by NICE guidelines – not harmful and may be beneficial to MS and symptoms such as fatigue
* Smoking may increase progression of disability
* Vitamin D controversial – not recommended but other sources say may be helpful
* Do not recommend omega 3 or 6 fatty acids to treat MS
