raynaud’s disease

23 Jul

Raynaud’s phenomenon is a condition that causes reduced blood supply to the fingers and toes in response to certain conditions such as, coldness, and cases of emotional stress. It causes pain, numbness and tingling in the areas affected and can be reversed through lifestyle and medical treatment.

- In most populations, Raynaud’s phenomenon is found to affect 3-5% of the general population
- A 7-year study found that in white patients within the US, prevalence rates were 11% in women and 8% in men [1]
- The prevalence ranges from 2-20% of women and 1-12% in men depending on factors such as geographic location and population studied [2]
- In most cases, Raynaud’s phenomenon is in its primary stage (80-90%)
- More common in women than men
- Typically develops at a younger age (between the 20-30th years of life) [3]
- Primary- without being associated with another condition
  - Some evidence of inheritance (run in families)
- Secondary- association with another condition
  - Autoimmune conditions (eg. rheumatoid arthritis, lupus) 1 in 10 patients are found to develop an autoimmune condition after being diagnosed with primary Raynaud’s syndrome
  - Infections such as Hepatitis B and C as well as blood born viral infections
  - Cancer (eg. ALL, myeloma)- can cause secondary Raynaud’s
  - Medicines including;
  - Anti-migraine medications
  - Beta-blockers
  - Chemotherapy
  - Contraceptive pills
  - And other drugs used to treat high blood pressure, hormone replacement, decongestants and illegal drugs like cocaine.
- Injury and overuse
- History of frostbite damaging skin and tissues
- Vibration white finger (caused by vibrations from certain tools eg. hammer drills and chainsaws) [5]
Medical Students
Pathophysiological Mechanisms
- Three key mechanisms:
  - Decreased blood flow
  - Vasoconstriction of small blood vessels
  - Neurogenic and inflammatory immune involvement
Somatosensory Involvement
- Cold triggers A-delta and unmyelinated C-fibers
- Activates TRPM8 cold receptors
  - Promotes vasoconstriction, thermogenesis, and cold avoidance
Sympathetic Nervous System Response
- Cold exposure → norepinephrine and neuropeptide release
- Causes arteriole smooth muscle contraction → reduced cutaneous blood flow
- Endothelin-1 plays a role in secondary Raynaud by enhancing vasoconstriction
Primary Raynaud Phenomenon
- Increased sensitivity of alpha-2 adrenergic receptors in digital/cutaneous vessels
- Triggered by cold and emotional stress
- Managed with alpha-2 adrenergic blockers
Secondary Raynaud Phenomenon
- Due to underlying diseases (e.g. connective tissue disorders)
- Impaired endothelial function → persistent vasoconstriction and tissue ischemia
Patients
- Blood vessels narrow too much, leading to poor blood flow
- Can be triggered by cold or emotional stress
- Caused by:
  - Reduced blood flow
  - Overactive nerve and immune responses
How the Body Senses Cold
- Special nerves sense temperature changes
- These nerves tell the body to:
  - Narrow blood vessels
  - Keep in heat
  - Avoid cold environments
Why Do Fingers and Toes Change Colour?
- The nervous system reacts by tightening blood vessels
- Less blood gets to the skin → fingers/toes may turn white, blue, or red
- This can feel painful, tingly, or numb
Primary Raynaud’s
- Happens on its own (not linked to other diseases)
- Small blood vessels in the fingers or toes overreact
- Episodes happen with cold or stress
- Usually not dangerous but uncomfortable
Secondary Raynaud’s
- Caused by another condition (like lupus or scleroderma)
- Blood vessels are more damaged
- Poor circulation can lead to sores or ulcers [4]
- Autoimmune diseases (eg. diabetes, arthritis, MS)
- Chemical exposure
- Smoking
- Injury/ trauma to the skin
- Overuse of actions such as using vibrating tools or typing
- Certain medications (see above) [6]
- Coldness
- Burning pain
- Tingling (paraesthesia)
- Discolouration of the fingers
- Cyanosis (blueness)
- Pallor (paleness)
- Ulcer formation and tissue damage in sever cases of Raynaud’s syndrome [7]
- Clinical examination where hands are placed in cold water/air to check for the presentation of Raynaud’s syndrome in the clinic
- Blood tests including;
  - A full blood count to check for infection
  - Antinuclear antibodies test (presence of proteins that protect your immune system) to check for an abnormally reactive immune system
  - Erythrocyte sedimentation rate (tests how quickly red blood cells can settle to the bottom of a test tube) to check for an immune system disorder (overreaction of the immune system) [5]
- Chilblains
- Acrocyanosis- blueness triggered by the cold
- Erythromelalgia- redness of the hands/feet
- Obstructive vessel conditions (eg. embolism)
- Livedo reticularis- blue discolouration of the skin and mottled skin (marked spots with patches of colour)
- Peripheral (hands/feet) nerve injury
- Shoulder-hand syndrome- causes continuous pain in the hands/feet associated with vessel reflex changes [3]
Medical students
- Lifestyle changes:
  - Avoidance of cold and smoking cessation
  - Use of relaxation techniques (e.g., biofeedback) or counselling if stress is a trigger
- Medications:
  - Vasodilating calcium channel blockers (e.g., nifedipine, amlodipine, felodipine, isradipine)
  - Treatment of Secondary Raynaud Syndrome:
    Focus on treating the underlying disorder
    Similar medications to Primary Raynaud Syndrome:
    Calcium channel blockers (e.g., nifedipine, amlodipine, felodipine, isradipine)
    Additional treatments for ischemic ulcers may include antibiotics, analgesics, and surgical debridement
- Low-dose aspirin may prevent thrombosis but could worsen vasospas
Patients
- Lifestyle changes:
  - Avoidance of cold and smoking cessation
  - Use of relaxation techniques (e.g., biofeedback) or counselling if stress is a trigger
- Medications:
  - Vasodilating (blood vessel widening) drugs called calcium channel blockers (blocks the calcium intake to the heart) (e.g., nifedipine, amlodipine, felodipine, isradipine)
  - Treatment of Secondary Raynaud Syndrome:
    Focus on treating the underlying disorder
    Similar medications to Primary Raynaud Syndrome:
    Calcium channel blockers (e.g., nifedipine, amlodipine, felodipine, isradipine)
    Additional treatments for ischemic ulcers (sores caused by a lack of oxygen supply) may include antibiotics, analgesics, and surgical debridement (treating a wound in the skin)
    Low-dose aspirin may prevent thrombosis (blood clot formation) but could worsen vasospasm (narrowing of the arteries caused by the constant narrowing movement of the arteries) [7]
- Sore areas of the fingers may progress into tissue damage and death (gangrene) [6]
- Raynaud’s is a rare disease
- It only affects fingers and toes
- Raynaud’s phenomenon is caused by poor circulation
- The only treatment is to stay warm
- Symptoms only include red, white and blue discolouration [8]
- How can I avoid the reoccurrence of symptoms?
- How is it diagnosed?
- Is it a hereditary condition?
- Will Raynaud’s get worse over time?
- Raynaud’s Association
- NICE Guidelines
- NHS Inform
[1] https://emedicine.medscape.com/articl/331197-overview#a4
[2] https://link.springer.com/chapter/10.1007/978-1-4939-1526-2_3
[3] https://cks.nice.org.uk/topics/raynauds-phenomenon/background-information/prevalence-incidence/
[4]https://www.ncbi.nlm.nih.gov/books/NBK499833/#:~:text=Three%20mechanisms%20contribute%20to%20Raynaud,perception%20based%20on%20environmental%20stimuli.
[5] https://www.nhsinform.scot/illnesses-and-conditions/heart-and-blood-vessels/conditions/raynauds-phenomenon#causes-of-raynaud-s-phenomenon
[6] https://www.hopkinsmedicine.org/health/conditions-and-diseases/raynauds-phenomenon
[7] https://www.msdmanuals.com/en-gb/professional/cardiovascular-disorders/peripheral-arterial-disorders/raynaud-syndrome
[8] https://www.raynauds.org/2017/10/16/infographic-ten-myths-about-raynauds-phenomenon/