Diabetic neuropathy is a type of nerve damage caused by diabetes. While high blood sugar levels can injure nerve fibers throughout the body, diabetic neuropathy most often affects nerves in your legs and feet. Overtime, patients with diabetes can develop nerve problems. Risk rises with age, duration of diabetes, overweight, high blood pressure, high levels of blood fat and if blood sugar level is controlled.
Signs and Symptoms
Symptoms depend on which nerves are affected and the type of neuropathy. Symptoms can involve motor, sensory, autonomic or involuntary nervous system. Most patients experienced symptoms such as pain, numbness, tingling of the toes, feet, legs, hands, arms, and fingers. Symptoms are often minor and mild cases often go unnoticed until after several years where symptoms go worse. In some patients with focal neuropathy, onset of pain may be severe and sudden. Other symptoms include wasting of the muscles of the feet or hands; problems with urination; weakness; dizziness or faintness due to a drop in blood pressure after standing or sitting up; indigestion; nausea or vomiting; erectile dysfunction in men or vaginal dryness in women
Types of diabetic neuropathy
There are four main types of diabetic neuropathy, namely peripheral, proximal, autonomic and focal.
This is the most common type of diabetic neuropathy which causes pain, cramps, tingling or burning sensation, numbness or loss of feeling first in the feet, legs, and toes then later in the arms and hands. Some experienced increased sensitivity to touch and serious foot problems like infections, ulcers, bone deformity. These symptoms are often worse at night.
This type of neuropathy affects the eyes, lungs, heart, blood vessels, digestive system, urinary tract, sex organs and sweat glands. It affects blood pressure and cause hypoglycemia unawareness wherein people no longer experience the warning signs of low blood sugar levels. Other symptoms include difficulty in swallowing, gastroparesis, increased or decrease sweating, increased hard rate even at rest, inability to adjust blood pressure and heart rate which may cause you to faint or feel lightheaded due to sharp drops in blood pressure after sitting or standing, urinary retention, erectile dysfunction in men, vaginal dryness in women and other sexual difficulties.
Also called as radiculoplexus neuropathy, diabetic amyotrophy or femoral neuropathy. This type of neuropathy affects the buttocks, thigh, hips causing weakness of the legs. Patients with this type of neuropathy often have difficulty in rising from sitting position and weight loss. This is more common in patients with type 2 diabetes and older adults. Symptoms sometimes improve partially overtime, however, symptoms may worsen before they get better.
Focal Neuropathy/ Mononeuropathy
The onset of symptoms for this type of neuropathy is most common in older adults and is experienced as sudden and severe weakness of one or a group of nerves causing muscle pain or weakness. Any nerve in the body can be affected such as the eyes, ears, facial muscles, chest, lower back, thighs, buttocks, legs and feet. Although mononeuropathy causes severe pain, it usually diminishes and disappears on its own over a few weeks or months.
The exact cause on why prolonged exposure of delicate nerve fibers to high blood sugar is unknown, but nerve damage is likely due to a combination of multiple factors, including complex interaction between nerves and blood vessels. Other factors include inflammation in the nerves caused by autoimmune response, lifestyle factors such as alcohol abuse and smoking, mechanical injury to nerves such as carpal tunnel syndrome or other genetic factors unrelated to diabetes that make people more susceptible to nerve damage.
Diabetic neuropathy may cause several complications. Because nerve damage can cause a lack of feeling in your feet, small cuts and sores may go unnoticed and eventually become seriously infected and ulcerated. This condition may even go worse when infections spread to the bone and cause tissue death – gangrene. Gangrenous feet are very difficult to treat and may require amputation of a toe, foot or even the lower leg. Charcot joint occurs when a joint deteriorates because of nerve damage. This condition is marked by swelling, instability, loss of sensation and sometimes deformity of the joint. Other complications involving gastrointestinal, urinary and sexual dysfunction also occur.
Diagnosis and Tests
Physicians usually diagnose diabetic neuropathy based on the symptoms presented. Upon clinic visit, your doctor will check your blood pressure and heart rate, examine your tendon reflexes, muscle strength and tone and your sensitivity to touch, position changes, vibration and temperature.
Your doctor may conduct other tests as well as part of diagnosis. These tests include filament test to test your sensitivity to touch using monofilament; electromyography (EMG) which measures electrical discharges produced in your muscles; nerve conduction studies which measure the transmission of electrical current through the nerve or how quickly the nerves in your arms and legs conduct electrical signals; quantitative sensory testing which is used to assess how your nerves respond to temperature changes and vibration.
Treatment and Management
Goals of treatment include slowing the progression of the disease, relieving pain and managing complications and restoring function.
By keeping blood sugar level within target range can help delay the progression of diabetic neuropathy and may even improve some of the symptoms you are already experiencing. Your medical doctor will determine the best target range for you depending on your age, duration of diabetes, presence of other medical conditions and your overall health. Avoiding alcoholic beverages, smoking cessation, keeping your blood pressure under control, good foot care, maintaining a healthy weight and being active are some measures to help slow down nerve damage.
Most pain relievers have side effects and must be weighed against the benefits they offer. Not all pain relievers work for everyone. Alternative therapies that may help relieve pain include acupuncture, physical therapy or capsaicin cream. These therapies can be used alone or in conjunction with medications.
Some of the pain relieving medications include antidepressants and anti- seizure drugs. Antidepressants such as tricyclic antidepressant medications (TCA) may provide temporary relief for mild to moderate symptoms. Examples of TCA include desipramine, imipramine, amitriptyline.
Depending on the organ or system involved, specific treatment exists for many complications of neuropathy. For example, antispasmodic drugs and behavioural technique and devices such as timed urination and pessaries can help in treating loss of bladder control. For digestive problems like gastroparesis, reducing fat and fiber in the diet and smaller meals may help prevent symptoms of indigestion, nausea, vomiting and belching. While several medications may be used to treat orthostatic hypotension, this condition is often helped with simple lifestyle measures (i.e. drink plenty of water, avoid alcohol, sitting or standing slowly). Some doctors recommend compression stockings or an abdominal binder.
Below are some recommendations on how to prevent diabetic neuropathy:
Consistently well controlled blood sugar levels.
Eat a well balanced diet.
Well controlled blood pressure.
Stop tobacco and avoid alcoholic beverages.
Daily foot care.