Raynaud's disease refers to a disorder in which the fingers or toes (digits)suddenly experience decreased blood circulation.
Raynaud's disease can be classified as one of two types: primary (or idiopathic) and secondary (also called Raynaud's phenomenon).
Primary and idiopathic are words used to describe a condition which occurs byitself, with no other accompanying conditions that could be considered the cause. Primary Raynaud's disease is more mild, and causes fewer complications.About half of all cases of Raynaud's disease are of this type. Women are five times more likely than men to develop primary Raynaud's disease, and the average age of diagnosis is between 20 and 40 years. About 30% of all cases ofprimary Raynaud's disease progress after diagnosis, while 15% of cases actually improve.
Secondary Raynaud's disease is more complicated, severe, and more likely to progress. A number of medical conditions predispose a person to secondary Raynaud's disease, including:
- Scleroderma. Scleroderma is a serious disease of the connective tissue, in which tissues of the skin, heart, esophagus, kidney, and lung become thickened, hard, and constricted. About 30% of patients who develop scleroderma will first develop Raynaud's disease.
- Otherconnective tissue diseases, including systemic lupus erythematosus, rheumatoid arthritis, dermatomyositis, and polymyositis.
- Diseases which result in blockages of arteries (including atherosclerosis or hardening of the arteries).
- A severe form of high blood pressure which is caused by diseased arteries in the lung (called pulmonary hypertension).
- A number ofnervous system disorders, including herniated discs in the spine, strokes, tumors within the spinal cord, polio, and carpal tunnel syndrome.
- A variety of blood disorders.
- Injuries, including those due to exposure to constant vibration (workers who use chainsaws, jackhammers, or other vibrating equipment), repetitive movements (typists and piano players), electric shock, or extreme cold (frostbite).
- The use of certain medications, including drugs used for migraine headaches, high blood pressure, and some cancer chemotherapy agents.
Both primary and secondary types of Raynaud's symptoms are believed to be dueto over-reactive arterioles (small arteries). While cold normally causes themuscle which makes up the walls of arteries to contract (squeeze down to become smaller), in Raynaud's disease the degree is extreme. Blood flow to the area is thus severely restricted. Some attacks may also be brought on or worsened by anxiety or emotional distress.
Classically, there are three distinct phases to an episode of Raynaud's symptoms. When first exposed to cold, the arteries respond by contracting intensely. The digits (fingers or toes) in question (or in rare instances, the tip ofthe nose or tongue) become pale and white as they are deprived of blood flowand, thus, oxygen. In response, the veins and capillaries dilate (expand). Because these vessels carry deoxygenated blood, the digit turns a bluish shade. The digit often feels cold, numb, and tingly. After the digit begins to warm up again, the arteries dilate. Blood flow increases significantly, and thedigits turn a bright red. During this phase, the patient often describes thedigits as feeling warm, and throbbing painfully.
Raynaud's disease may initially only affect the tips of the fingers or toes.When the disease progresses, it may eventually affect the entire finger or toe. Ultimately, all the fingers or toes may be affected. About 10% of the time, a complication called sclerodactyly may occur. In sclerodactyly, the skin over the affected digits becomes tight, white, thick, smooth, and shiny.
When the most serious complications of Raynaud's disease or phenomenon occur,the affected digits develop deep sores (ulcers) in the skin. The tissue mayeven die (gangrene), requiring amputation. This complication only occurs about 1% of the time in primary Raynaud's disease.
While the patient's symptoms will be the first clue pointing to Raynaud's disease, a number of tests may also be performed to confirm the diagnosis. Special blood tests called the antinuclear antibody test (ABA) and the erythrocytesedimentation rate (ESR) are often abnormal when an individual has a connective tissue disease.
When a person has connective tissue disease, his or her capillaries are usually abnormal. A test called a nailfold capillary study can demonstrate such abnormalities. In this test, a drop of oil is placed on the skin at the base ofthe fingernail. This allows the capillaries in that area to be viewed more easily with a microscope.
A cold stimulation test may also be performed. In this test, specialized thermometers are taped to each of the digits that have experienced episodes of Raynaud's disease. The at-rest temperature of these digits is recorded. The hand or foot is then placed completely into a container of ice water for 20 seconds. After removing the hand or foot from this water, the temperature of thedigits is recorded immediately. The temperature of the digits is recorded every five minutes until they reach the same temperature they were before beingput into the ice water. A normal result occurs when this pre-test temperatureis reached in 15 minutes or less. If it takes more than 20 minutes, the testis considered suspicious for Raynaud's disease or phenomenon.
The first type of treatment for Raynaud's symptoms is simple avoidance. Patients need to stay warm, and keep hands and feet well covered in cold weather.Patients who smoke cigarettes should stop, because nicotine will worsen the problem. Most people (especially those with primary Raynaud's) are able to deal with the disease by taking these basic measures.
People with more severe cases of Raynaud's disease may need to be treated with medications to attempt to keep the arterioles relaxed and dilated. Some medications which are more commonly used to treat high blood pressure (calcium-channel blockers, reserpine), are often effective for Raynaud's symptoms. Nitroglycerine paste can be used on the affected digits, and seems to be helpfulin healing skin ulcers.
When a patient has secondary Raynaud's phenomenon, treatment of the coexisting condition may help control the Raynaud's as well. In the case of connectivetissue disorders, this often involves treatment with corticosteroid medications.
Because episodes of Raynaud's disease have also been associated with stress and emotional upset, the disease may be improved by helping a patient learn tomanage stress. Regular exercise is known to decrease stress and lower anxiety. Hypnosis, relaxation techniques, and visualization are also useful methodsto help a patient gain control of his or her emotional responses. Biofeedback training is a technique during which a patient is given continuous information on the temperature of his or her digits, and then taught to voluntarily control this temperature.
Some alternative practitioners believe that certain dietary supplements and herbs may be helpful in decreasing the vessel spasm of Raynaud's disease. Suggested supplements include vitamin E (found in fruits, vegetables, seeds, andnuts), magnesium (found in seeds, nuts, fish, beans, and dark green vegetables), and fish oils. Several types of herbs have been suggested, including peony (Paeonia lactiflora) and dong quai (Angelica sinensis). The circulatory herbs cayenne (Capsicum frutescens), ginger (Zingiber officinale), and prickly ash (Zanthoxylum americanum) can help enhance circulation to the extremities.
The prognosis for most people with Raynaud's disease is very good. In general, primary Raynaud's disease has the best prognosis, with a relatively small chance for serious complications (1%). In fact, about 50% of all patients do well by taking simple precautions, and never even require medications. The prognosis for people with secondary Raynaud's disease (or phenomenon) is less predictable. This prognosis depends greatly on the severity of the patient's other associated condition (e.g. scleroderma or lupus).
There is no known way to prevent the development of Raynaud's disease. Once an individual realizes that he or she suffers from this disorder, however, steps can be taken to reduce the frequency and severity of episodes.