Diabetic Neuropathy: Symptoms, Treatment & More
Diabetic Neuropathy Overview Diabetic neuropathy, a common complication of diabetes of diabetes,, is damage to the nerves that allow you to feel sensations such as pain. There are a number of ways that diabetes damages the nerves, but they all seem related to blood sugar being b eing too high for a long period of time. Diabetes-related nerve damage can be b e painful, but it isn't severe pain in most cases. There are four types of diabetic neuropathy: peripheral, au tonomic, proximal, and focal.
Diabetic Peripheral Neuropathy The areas of the body most commonly affected by diabetic peripheral neuropathy are the feet and legs. Nerve legs. Nerve damage in the feet can result in a loss of foot sensation, increasing your risk of foot problems. Injuries and sores on the feet may go unrecognized due to lack of sensation. Therefore, you should practice proper skin and foot care. Rarely, other areas of the body b ody such as the arms, abdomen, and back may be affected. Symptoms of diabetic peripheral neuropathy may include: •
•
Tingling Numbness (severe or long-term numbness can become permanent)
•
Burning (especially in the evening)
•
Pain
In most cases, early symptoms of diabetic peripheral neuropathy will become less when blood sugar is under control. Medications can be taken to help control the discomfort if neede d. To prevent peripheral neuropathy: •
Work with your doctor to keep your blood glucose under tight control
To help prevent the complications of peripheral neuropathy: •
Examine your feet and legs daily.
•
Apply lotion if your feet are dry.
•
Care for your nails regularly. (Go to a podiatrist a podiatrist,, if necessary).
•
Wear properly fitting footwear and wear them all the time to prevent foot injury.
Diabetic Autonomic Neuropathy Diabetic autonomic neuropathy most often affects the digestive system, system, especially the stomach, blood vessels, urinary system, and sex organs. To prevent autonomic neuropathy, continuously keep your blood sugar levels well controlled. Symptoms of neuropathy of the digestive system may include: •
Bloating
•
Diarrhea
•
Constipation
•
Heartburn
•
Nausea
•
Vomiting
•
Feeling full after small meals
Treatments of autonomic neuropathy of the digestive system may include: •
Eat smaller meals
•
Medication
Symptoms of autonomic neuropathy of the blood vessels may include: •
Blacking out when you stand up quickly
•
Increased heart rate
•
Dizziness
•
Low blood pressure
•
Nausea
•
Vomiting
•
Early fullness
Treatments of autonomic neuropathy of the blood vessels may include: •
Avoid standing up too quickly
•
Medications
•
Wearing special stockings
Symptoms of autonomic neuropathy of the male sex organs may include: •
Unable to have or maintain an erection (erectile dysfunction)*
•
"Dry" or reduced ejaculations
*Note: Impotence needs to be evaluated by your doctor. It may be caused by your medicines or factors other than diabetes. Treatments of autonomic neuropathy of the male sex organs include: •
Counseling
•
Penile implant
•
Vacuum erection device
•
Penile injections
•
Medication
Symptoms of autonomic neuropathy of the female sex organs may include: •
Decrease in vaginal lubrication
•
Decrease in number of orgasms or lack of orgasm
Treatments of autonomic neuropathy of the female sex organs include: •
Counseling
•
Vaginal estrogen creams, suppositories and rings
•
Lubricants
Symptoms of autonomic neuropathy of the urinary system may include: •
Unable to completely empty bladder
•
Bloating
•
Incontinence (leaking urine)
•
Increased urination at night
Treatments of autonomic neuropathy of the urinary system include: •
Medication
•
Self-catheterization (inserting a catheter into the bladder to release urine)
•
Surgery
Diabetic Proximal Neuropathy Diabetic proximal neuropathy causes pain (usually on one side) in the thighs, hips, or buttocks. It can also lead to weakness in the legs. Treatment for weakness or pain is usually needed and may include medication and physical therapy. The recovery varies, depending on the type of nerve damage. Prevention consists of keeping blood sugar under tight control.
Diabetic Focal Neuropathy Diabetic focal neuropathy can also appear suddenly and affect specific nerves, most often in the head, torso, or leg, causing muscle weakness or pain. Symptoms of diabetic focal neuropathy may include: •
double vision
•
eye pain
•
•
•
paralysis on one side of the face (Bell's palsy) severe pain in a certain area, such as the lower back or leg(s) chest or abdominal pain that is sometimes mistaken for another condition such as heart attack or appendicitis
Diabetic focal neuropathy is painful and unpredictable, however, it tends to improve by itself over weeks or months and does not tend to cause long-term damage.
Other Nerve Conditions Seen With Diabetes People with diabetes can also develop other nerve-related conditions, such as nerve compressions (entrapment syndromes). Carpal tunnel syndrome is a very common type of entrapment syndrome and causes numbness and tingling of the hand and sometimes muscle weakness or pain.
Prevention of Diabetic Neuropathy Keeping tight control of your blood sugar levels will help prevent many of these diabetes-related nerve conditions. Talk to your doctor about optimizing your individual diabetes treatment plan. WebMD Medical Reference
Reviewed by John A. Seibel, MD on March 08, 2009 © 2009 WebMD, LLC. All rights reserved. REFERENCES: American Diabetes Association (ADA): "Diabetic Neuropathy (Nerve Damage) and Diabetes." ADA: "Additional Specific Types of Diabetic Neuropathy." National Diabetes Education Program: "Prevention and Early Intervention for Diabetes Foot Problems."
Last Editorial Review: 11/4/2009
Diabetic neuropathy Diabetic neuropathy is damage to nerves in the body that occurs due to high blood sugar levels from diabetes.
Causes Nerve injuries are caused by decreased blood flow and high blood sugar levels. They are more likely to develop if blood sugar levels are not well controlled. About half of people with diabetes will develop nerve damage. Most of the time symptoms do not begin until 10 to 20 years after diabetes has been diagnosed. Nerve injuries may affect: • • •
Nerves in the skull (cranial nerves) Nerves from the spinal column and their branches Nerves that help your body manage vital organs, such as the heart, bladder, stomach, and intestines (called autonomic neuropathy)
Symptoms Symptoms often develop slowly over several years. They can vary dep ending on the nerves that are affected. People with diabetes may have trouble digesting food. These problems can make your diabetes harder to control. Symptoms of this problem are: • • • • •
Feeling full after eating only a small amount of food Heartburn and bloating Nausea, constipation, or diarrhea Swallowing problems Throwing up food you have eaten a few hours after a meal
Tingling or burning in the arms and legs may be an early sign of nerve damage. These feelings often start in your toes and feet. You may have deep pain, often in the feet and legs. Nerve damage may cause you to lose feeling in your arms and legs. Bec ause of this you may: • • •
Not notice when you step on something sharp Not know that you have a blister or small cut Not notice when you touch something that is too hot or cold
Damage to nervves in your heart and blood vessels may cause you to: • • •
Feel light-headed when you stand up (orthostatic hypotension) Have a fast heart rate Not notice angina, the chest pain that warns of heart disease and heart attack
Other symptoms of nerve damage are: •
• •
•
Sexual problems. Men may have problems with erections. Women may have trouble with vaginal dryness or orgasm. Not being able to tell when your blood sugar gets too low Bladder problems. You may leak urine and may not be able to tell when your bladder is full. Some people are not able to empty their bladder. Sweating too much -- when the temperature is cool, when you are at rest, or at other unusual times
Exams and Tests A physical exam may show: • •
A lack of reflexes in the ankle A loss of feeling in the feet (your health care provider will check this with a brush-like instrument called a monofilament)
• •
Changes in the skin Drop in blood pressure when you stand up after sitting or lying down
Tests that may be done include: • •
Electromyogram (EMG) -- a recording of electrical activity in muscles Nerve conduction velocity tests (NCV) -- a recording of the speed at which signals travel along nerves
Treatment It is very important to keep your blood sugar in a healthy range. You should learn the basic steps for managing your diabetes, avoiding its complications, and staying as healthy as possible. These steps will include diet, exercise, and sometimes medicines. You may need to check your blood sugar daily, or more often. Your doctor will help you by taking blood tests and other tests. See also: • •
Type 1 diabetes Type 2 diabetes
The following medications may be used to reduce symptoms in the feet, legs, and arms: •
•
•
Certain drugs that are also used to treat depression, such as amitriptyline (Elavil), doxepin (Sinequan), or duloxetine (Cymbalta) Certain drugs that are also used to treat seizures, such as gabapentin (Neurontin), pregabalin (Lyrica), carbamazepine (Tegretol), and valproate (Depakote) Pain medicines
Treatments for nausea and vomiting may include: •
• •
Taking medicines that help food move more quickly through your stomach and intestines Sleeping with your head raised Eating smaller, more frequent meals
Diarrhea, constipation, bladder problems, and other symptoms are treated as needed. See also: • •
Bowel retraining Neurogenic bladder
Drugs such as sildenafil (Viagra), vardenafil (Levitra), and tadalafil (Cialis) may be used for treating impotence. Discuss these medicines with your doctor before taking them. To keep your feet healthy, you should: • •
•
Check and care for your feet EVERY DAY Get a foot exam by your doctor at least once every 6 to 12 months, and learn whether you have nerve damage. Make sure you wear the right kind of shoes.
See also: Diabetes foot care
Outlook (Prognosis) Treatment relieves pain and can control some symptoms, but the disease generally continues to get worse.
Possible Complications • • • • •
Bladder and kidney infections Injury to the feet due to loss of feeling Muscle damage Poor blood sugar control due to nausea and vomiting Skin and soft tissue damage and risk of amputation
Neuropathy may also hide angina, the warning chest pain for heart disease and heart attack.
When to Contact a Medical Professional Call your health care provider if you develop symptoms of diabetic neuropathy.
Prevention Tight control of blood sugar levels may prevent neuropathy in many people with type 1 diabetes, and may reduce the severity of symptoms. In addition, regular foot care can prevent a small infection from getting worse. This is why no appointment for diabetes care is complete without a thorough foot examination.
Alternative Names Nerve damage - diabetic
References Eisenbarth GS, Polonsky KS, Buse JB. Type 1 diabetes mellitus. In: Kronenberg H M, Melmed S, Polonsky KS, Larsen PR. Williams Textbook of Endocrinology. 11th ed. Philadelphia, Pa: Saunders Elsevier; 2008:chap 31. Wong MC, Chung JW, Wong TK. Effects of treatments for symptoms of painful diabetic neuropathy: systematic review. BMJ . 2007;335:87. American Diabetes Association. Standards of medical care in diabetes--2011. Diabetes Care. 2011 Jan;34 Suppl 1:S11-61.
Update Date: 6/28/2011 Updated by: Ari S. Eckman, MD, Chief, Division of Endocrinology, Diabetes and Metabolism, Trinitas Regional Medical Center, Elizabeth, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
Diabetic Neuropathy •
Author: Helen C Lin, MD; Chief Editor: Nicholas Lorenzo, MD
Background Neuropathies are characterized by a progressive loss of nerve fiber function. A widely accepted definition of diabetic peripheral neuropathy is "the presence of symptoms and/or signs of peripheral nerve dysfunction in people with diabetes a fter exclusion of other causes."[1] Neuropathies are the most common complication of diabetes mellitus (DM), affecting up to 50% of patients with type 1 and type 2 DM. In type 1 diabetes mellitus, distal polyneuropathy typically becomes symptomatic after many years of chronic prolonged hyperglycemia. Conversely, patients with type 2 diabetes mellitus may present with distal polyneuropathy after only a few years of known poor glycemic control; sometimes, these patients already have neuropathy at the time of diagnosis. (See Clinical Presentation.) Neuropathies severely decrease patients' quality of life (QOL). Furthermore, while the primary symptoms of neuropathy can be highly unpleasant, the secondary complications (eg, falls, foot ulcers, cardiac arrhythmias, and ileus) are even more serious and can lead to fractures, amputations, and even death in patients with DM. Since diabetic neuropathy can manifest with a wide variety of sensory, motor, and autonomic symptoms, a structured list of symptoms can be used to help screen all diabetic patients for possible neuropathy (see History). Physical examination of patients with suspected distal sensory
motor or focal (ie, entrapment or noncompressive) neuropathies should include assessments for both peripheral and autonomic neuropathy (see Physical Examination). Multiple consensus panels recommend the inclusion of electrophysiologic testing in the evaluation of diabetic neuropathy. An appropriate array of electrodiagnostic tests includes both nerve conduction testing and needle EMG of the most distal muscles usually affected. (See Workup.) Management of diabetic neuropathy should begin at the initial diagnosis of diabetes. The primary care physician needs to be alert for the development of neuropathy—or even its presence at the time of initial diabetes diagnosis—because failure to diagnose diabetic polyneuropathy can lead to serious consequences, including disability and amputation. In addition, the primary care physician is responsible for educating patients about the acute and chronic complications of diabetes (see Patient Education). Patients with diabetic peripheral neuropathy require more frequent follow-up, with particular attention to foot inspection to reinforce the need for regular self-care. (See Treatment Strategies and Management.) Management of diabetic neuropathy includes 2 approaches: therapies for symptomatic relief and those that may slow the progression of neuropathy. Of all treatments, tight and stable glycemic control is probably the most important for slowing the progression of neuropathy. Many medications are available for the treatment of diabetic neuropathic pain, although most of them are not specifically approved by the United States Food and Drug Administration for this use. Nonpharmacologic treatment includes rehabilitation, which may comprise physical, occupational, speech, and recreational therapy. (See Medication.)
Anatomy A review of the anatomy of the peripheral nervous system can facilitate understanding of the classification of diabetic peripheral neuropathy. Peripheral neurons can be categorized broadly as motor, sensory, or autonomic. Motor neurons originate in the central nervous system (CNS) and extend to the anterior horn of the spinal cord. From the anterior horn, they exit the spinal cord (via ventral roots) and combine with other fibers in the brachial or lumbar plexuses and innervate their target organs through peripheral nerves. Sensory neurons originate at the dorsal root ganglia (which lie outside the spinal cord) and follow a similar course with motor neurons. Sensory neurons are subdivided into categories according to the sensory modality they convey (see the Table below). Autonomic neurons consist of sympathetic and parasympathetic types. In the periphery, preganglionic fibers leave the CNS and synapse on postganglionic neurons in the sympathetic chain or in sympathetic ganglia.
The smaller fibers are affected first in DM. With continued exposure to hyperglycemia, the larger fibers become affected. Fibers of different size mediate different types of sensation, as shown in the table below. Table. Subdivisions of Sensory Neurons (Open Table in a new window) Fiber Type
Size
Modality
Myelinati on
A-alpha (I)
13-20 micrometers
Limb proprioception
Yes
A-beta (II)
6-12 micrometers
Limb proprioception, vibration, pressure
Yes
A-delta (III)
1-5 micrometers Mechanical sharp pain
Yes
C (IV)
0.2-1.5 micrometers
No
Thermal pain, mechanical burning pain
Pathophysiology The factors leading to the development of diabetic neuropathy are not understood completely, and multiple hypotheses have been advanced.[2, 3, 4, 5, 6, 7, 8, 9, 10, 11] It is generally accepted to be a multifactorial process. Development of symptoms depends on many factors, such as total hyperglycemic exposure and other risk factors such as elevated lipids, blood pressure, smoking, increased height, and high exposure to other potentially neurotoxic agents such as ethanol. Genetic factors may also play a role.[12] Important contributing biochemical mechanisms in the development of the more common symmetrical forms of diabetic polyneuropathy likely include the polyol pathway, advanced glycation end products, and oxidative stress. For more information, see Type 2 Diabetes and TCF7L2.
Polyol pathway Hyperglycemia causes increased levels of intracellular glucose in nerves, leading to saturation of the normal glycolytic pathway. Extra glucose is shunted into the polyol pathway and converted to sorbitol and fructose by the enzymes aldose reductase and sorbitol dehydrogenase.[13] Accumulation of sorbitol and fructose lead to reduc ed nerve myoinositol, decreased membrane Na+/K + -ATPase activity, impaired axonal transport, and structural breakdown of nerves, causing abnormal action potential propagation. This is the rationale for the use of aldose reductase inhibitors to improve nerve conduction.[14]
Advanced glycation end products
The nonenzymatic reaction of excess glucose with proteins, nucleotides, and lipids results in advanced glycation end products (ACE) that may have a role in disrupting ne uronal integrity and repair mechanisms through interference with nerve cell metabolism and axonal transport.[15]
Oxidative stress The increased production of free radicals in diabetes may be detrimental via several mechanisms that are not fully understood. These include direct damage to blood vessels leading to nerve ischemia and facilitation of AGE reactions. Despite the incomplete understanding of these processes, use of the antioxidant alpha-lipoic acid may hold promise for improving neuropathic symptoms.[16, 17, 18]
Related contributing factors Problems that are a consequence of or co-contributors to these disturbed biochemical processes include altered gene expression with altered ce llular phenotypes, changes in cell physiology relating to endoskeletal structure or cellular transport, reduction in neurotrophins, and nerve ischemia.[19] Clinical trials of the best-studied neurotrophin, human recombinant nerve g rowth factor, were disappointing. With future refinements, however, pharmacologic intervention targeting one or more of these mechanisms may prove successful. In the case of focal or asymmetrical diabetic neuropathy syndromes, vascular injury or autoimmunity may play more important roles.[20]
Etiology Risk factors that are associated with more severe symptoms include the following[21] : • • • • • • • • •
Poor glycemic control Advanced age Hypertension Long duration of DM Dyslipidemia Smoking Heavy alcohol intake HLA-DR3/4 phenotype Tall height
Development of symptoms depends on many factors, such as total hyperglycemic exposure and other risk factors such as elevated lipids, blood pressure, smoking, increased height, and high exposure to other potentially neurotoxic agents such as ethanol. Genetic factors may also play a role.[12] Peripheral neuropathies have been described in patients with primary DM (types 1 and 2) and in those with secondary diabetes of diverse causes, suggesting a common etiologic mechanism
based on chronic hyperglycemia. The contribution of hyperglycemia has received strong support from the Diabetes Control and Complications Trial (DCCT).[22] An association between impaired glucose tolerance and peripheral neuropathy has been construed as further evidence of a dose-dependent effect of hyperglycemia on nerves, although this relationship remains an area of some controversy for type 2 d iabetes and prediabetes.[23, 24, 25, 26]
Epidemiology United States statistics A large American study estimated that 47% of p atients with diabetes have some peripheral neuropathy.[27] Neuropathy is estimated to be present in 7.5% of patients at the time of diabetes diagnosis. More than half of cases are distal symmetric polyneuropathy. Focal syndromes such as carpal tunnel syndrome (14-30%),[28, 29, 30] radiculopathies/plexopathies, and cranial neuropathies account for the rest. Solid prevalence data for the latter 2 less-common syndromes is lacking. The wide variability in symmetric diabetic polyneuropathy prevalence data is due to lack of consistent criteria for diagnosis, variable methods of selecting patients for study, and differing assessment techniques. In addition, because many patients with diabetic polyneuropathy are initially asymptomatic, detection is extremely dependent on careful neurologic examination by the primary care clinician. The use of additional diagnostic techniques, such as autonomic or quantitative sensory testing, might result in a higher recorded prevalence.[31, 32]
International statistics In a cohort of 4400 Belgian patients, Pirart et al found that 7.5% of patients already had neuropathy when diagnosed with diabetes.[33] After 25 years, the number with neuropathy rose to 45%. In the United Kingdom, the prevalence of diabetic neuropathy among the hospital clinic population was noted to be around 29%.[34]
Diabetic neuropathy in racial minorities No definite racial predilection has been demonstrated for diabetic neuropathy. However, members of minority groups (eg, Hispanics, African Americans) have more secondary complications from diabetic neuropathy, such as lower-extremity amputations, than whites.[21] They also have more hospitalizations for neuropathic complications.
Sex differences in diabetic neuropathy DM affects men and women with equal frequency. However, male patients with type 2 diabetes may develop diabetic polyneuropathy earlier than female patients,[35] and neuropathic pain causes more morbidity in females than in males.
Diabetic neuropathy and advancing age Diabetic neuropathy can occur at any age but is more common with increasing age and severity and duration of diabetes.
Prognosis Patients with untreated or inadequately treated diabetes have higher morbidity and complication rates related to neuropathy than patients with tightly controlled diabetes. Repetitive trauma to affected areas may cause skin breakdown, progressive ulceration, and infection. Amputations and death may result. Treating diabetic neuropathy is a difficult task for the physician and patient. Most of the medicines mentioned in the Medication section do not lead to complete symptom relief. Clinical trials are under way to help find new ways to treat symptoms and delay disease progression. Mortality is higher in people with cardiovascular autonomic neuropathy (CAN). The overall mortality rate over periods up to 10 years was 27 % in patients with DM and CAN detected, compared with a 5% mortality rate in those without e vidence of CAN. Morbidity results from foot ulceration and lower-extremity amputation. These 2 complications are the most common causes of hospitalization among people with DM in Western countries. Severe pain, dizziness, diarrhea, and impotence are common symptoms that decrease the QOL of a patient with DM. In patients with diabetic peripheral neuropathy, the prognosis is good, but the patient's QOL is reduced. For more information, go to Diabetic Foot. for more information, go to Diabetic Foot Infections.
Patient Education Controlling diet and nutrition are paramount to improving the secondary complications of diabetes, including neuropathy. Patients with diabetic neuropathy should wo rk with nutritionists or their primary care physicians to develop a realistic diet for lowering blood glucose and minimizing large fluctuations in blood glucose. Patients with diabetic neuropathy should be encouraged to remain as active as possible. However, those with significant sensory loss or autonomic dysfunction should be cau tioned about exercising in extreme weather conditions, wh ich may result in injury. For example, patients with extremity numbness may not be aware of frostbite injuries during prolonged cold exposure, or those with abnormal sweating may become easily overheated in hot conditions. In most cases, consultation with the patient's regular physician is reasonable be fore the initiation of a regular exercise program. Patients with diabetic neuropathy need to be educated on all aspects of their condition, and they need to know that it is very much affected by poor glycemic control. Prevention of diabetic
neuropathy is potentially best achieved by having near-euglycemic control from the onset of DM. Even in patients with symptoms of diabetic neuropathy, controlling blood glucose to euglycemic levels reduces pain significantly. When a person has poor control and becomes euglycemic quickly, pain may be exacerbated (possibly due to an insulin effect), but this pain disappears in a few days. The bottom line for patients is that medications are imperfect. Many result in no pain relief for certain patients. However, g lucose control is something that the patient can achieve that may reduce pain. The importance of protection and care of insensitive feet cannot be overemphasized. Patients should be instructed to trim their toenails with great care and to be fastidious about foot hygiene. Any fungal or bacterial infection mandates prompt medical attention. The need for well-fitting shoes should be stressed. Diabetic polyneuropathy is often associated with diabetic retinopathy and nephropathy. Patients with neuropathy should be counseled to seek appropriate eye care and discuss renal care and follow-up with their primary care physicians or endocrinologists. Patient education should begin in the primary care office. The following outline reviews some common questions and answers that can serve as a springboard for discussion.
What is diabetic neuropathy? Diabetic neuropathy is nerve damage caused by diabetes. In the United States, diabetes is one of the most common causes of nerve damage, also known as peripheral neuropathy. Diabetic neuropathy can affect nerves that supply feeling and movement in the arms and legs. It can also affect the nerves that regulate unconscious vital functions such as heart rate and digestion.
How does diabetic neuropathy occur? Doctors have been studying this problem for many years, but they do not yet understand exactly how diabetes damages nerves. However, they have observed that good control of blood sugar levels helps prevent diabetic neuropathy and slows its progression, especially in patients with type 1 diabetes.
What are the symptoms? Symptoms of diabetic neuropathy may include the following: • • • •
• • • •
Numbness or loss of feeling (usually in the feet and legs first, then the hands) Pain Muscle weakness Low blood pressure and dizziness when rising quickly from sitting or lying down Rapid or irregular heartbeats Trouble having an erection Nausea or vomiting Difficulty swallowing
•
Constipation or diarrhea
Pain from diabetic neuropathy may range from minor discomfort or tingling in toes to severe pain. Pain may be sharp or lightning-like, deep and aching, or burning. Extreme sensitivity to the slightest touch can also occur (allodynia).
How can I help prevent diabetic neuropathy? The following steps may help to prevent or slow the worsening of diabetic neuropathy[36] : • • • • •
• • •
Control diabetes; try to keep blood sugar at a normal level Maintain normal blood pressure Exercise regularly, according to the healthcare provider's recommendation Stop smoking Limit the amount of alcohol intake because excessive alcohol also can cause neuropathy or make it worse Eat a healthy diet and avoid elevated levels of triglycerides in the blood Maintain a healthy weight Keep follow-up appointments with the healthcare provider
How is diabetic neuropathy treated? No treatment is currently available to reverse neuropathy. The best approach is to control the diabetes and other risk factors. Muscle weakness is treated with support, such as b races. Physical therapy and regular exercise may help patients maintain the muscle strength they have. Pain medications may help make pain more tolerable. Medications can be used to treat nausea, vomiting, and diarrhea. Men who have trouble having erections because of neuropathy should talk to their healthcare providers. Medications can help a man achieve and maintain an erection, or prosthetic devices can be put in the penis. Preventing injuries such as burns, cuts, or broken b ones is especially important, because patients with neuropathy have more complications from simple injuries and may not heal as quickly as healthy individuals.
How can I take care of myself? Diabetes patients can take the following self-care measures: •
•
Work with primary care physicians and endocrinologists to control glucose levels Examine the skin of feet and lower legs regularly to look for injuries
•
•
See a healthcare provider promptly for calluses, sores on the skin, or other potential problems so they can be treated properly. Wear good-fitting, comfortable shoes that protect the feet
How long will the problem last? Once a person has neuropathy, the symptoms will persist indefinitely, but most people with diabetic neuropathy are able to lead active, fulfilling lives. Keeping blood sugar under good control may stop neuropathy from worsening. For excellent patient education resources, visit eMedicine's Diabetes Center and Erectile Dysfunction Center . Also, see eMedicine's patient education articles, Diabetes and Diabetic Foot Care. Updated: Nov 1, 2011 Helen C Lin, MD Assistant Professor of Neurology, Medical College of Wisconsin, Milwaukee Helen C Lin, MD is a member of the following medical societies: American Academy of Neurology and American Association of Neuromuscular and Electrodiagnostic Medicine
Definition By Mayo Clinic staff
Diabetic neuropathy is a type of nerve damage that can occur if you have diabetes. High blood sugar can injure nerve fibers throughout your bo dy, but diabetic neuropathy most often damages nerves in your legs and feet. Depending on the affected nerves, symptoms of diabetic neuropathy can range from pain and numbness in your extremities to problems with your digestive system, urinary tract, blood vessels and heart. For some people, these symptoms are mild; for others, diabetic neuropathy can be painful, disabling and even fatal. Diabetic neuropathy is a common serious complication of diabetes. Yet you can often prevent diabetic neuropathy or slow its progress with tight blood sugar control and a healthy lifestyle.
Symptoms By Mayo Clinic staff
There are four main types of diabetic neuropathy. You may have just one type or symptoms of several types. Most develop gradually, and you may not notice problems until considerable damage has occurred. For some people with type 2 diabetes, symptoms of neuropathy develop before diabetes is ever diagnosed.
The signs and symptoms of diabetic neuropathy vary, dep ending on the type of neuropathy and which nerves are affected. Peripheral neuropathy Peripheral neuropathy is the most common form of diabetic neuropathy. It affects the very ends of nerves first, starting with the longest nerves. That means your feet and legs are often affected first, followed by your hands and arms. Possible signs and symptoms of peripheral neuropathy include: •
• • • •
• •
Numbness or reduced ability to feel pain or changes in temperature, especially in your feet and toes A tingling or burning feeling Sharp, jabbing pain that may be worse at night Pain when walking Extreme sensitivity to the lightest touch — for some people, even the weight of a sheet can be agonizing Muscle weakness and difficulty walking Serious foot problems, such as ulcers, infections, deformities, and bone and joint pain
Autonomic neuropathy The autonomic nervous system controls your heart, bladder, lungs, stomach, intestines, sex organs and eyes. Diabetes can affect the nerves in any of these areas, possibly causing: •
•
• •
• • • •
• • • •
A lack of awareness that blood sugar levels are low (hypoglycemia unawareness) Bladder problems, including frequent urinary tract infections or urinary incontinence Constipation, uncontrolled diarrhea or a combination of the two Slow stomach emptying (gastroparesis), leading to nausea, vomiting and loss of appetite Erectile dysfunction in men Vaginal dryness and other sexual difficulties in women Increased or decreased sweating Inability of your body to adjust blood pressure and heart rate, leading to sharp drops in blood pressure when you rise from sitting or lying down (orthostatic hypotension) that may cause you to feel lightheaded or even faint Problems regulating your body temperature Changes in the way your eyes adjust from light to dark Difficulty exercising Increased heart rate when you're at rest
Autonomic neuropathy is most likely to occur in peo ple who have had poorly controlled diabetes for many years. Radiculoplexus neuropathy (diabetic amyotrophy) Instead of affecting the ends of nerves, like peripheral neuropathy, radiculoplexus neuropathy
affects nerves closer to your hips or shoulders. Also called diabetic amyotrophy, femoral neuropathy, or proximal neuropathy, this condition is more common in people with type 2 diabetes and older adults. Though the legs are affected more often, this type of neuropathy may affect nerves in the arms or even the abdomen. Symptoms are usually on one side of the body, though in some cases symptoms may spread to the other side too. Most people improve at least partially over time, though symptoms may worsen before they get better. This co ndition is often marked by: • • • • •
Sudden, severe pain in your hip and thigh or buttock Eventual weak and atrophied thigh muscles Difficulty rising from a sitting position Unintentional weight loss Abdominal swelling, if the abdomen is affected
Mononeuropathy The term mononeuropathy means damage to just one nerve. The nerve may be in the arm, leg or face. Mononeuropathy, which may also be called focal neuropathy, often comes on suddenly. It's most common in older adults. Although mononeuropathy can cause severe pain, it usually doesn't cause any long-term problems. Symptoms usually diminish and disappear on their own over a few weeks or months. Signs and symptoms depend on which nerve is involved and may include: • • • • •
Difficulty focusing your eyes, double vision or aching behind one eye Paralysis on one side of your face (Bell's palsy) Pain in your shin or foot Pain in the front of your thigh Chest or abdominal pain
Sometimes mononeuropathy occurs when a nerve is compressed. Carpal tunnel syndrome is a common type of compression neuropathy in people with diabetes. Signs and symptoms of carpal tunnel syndrome include: •
• •
Numbness or tingling in your fingers or hand, especially in your thumb, index finger, middle finger and ring finger A sense of weakness in your hand and a tendency to drop things Worsening of symptoms upon awakening or while gripping something
When to see a doctor Seek medical care if you notice: •
•
• •
A cut or sore on your foot that doesn't seem to be healing, is infected or is getting worse Unusual burning, tingling, weakness or pain in your hands or feet that interferes with your daily routine or your sleep Dizziness Changes in your digestion, urination or sexual function
These symptoms don't always indicate nerve damage, but they may signal other problems that require medical care. In either case, early diagnosis and treatment offer the best chance for controlling symptoms and preventing more-severe problems. Even minor sores on the feet that don't heal can turn into ulcers. In the most severe cases, untreated foot ulcers may become gangrenous — a condition in which the tissue dies — and require surgery or even amputation of your foot. Early treatment can help prevent this from happening.
Causes By Mayo Clinic staff
Damage to nerves and blood vessels Prolonged exposure to high blood sugar (glucose) can damage delicate nerve fibers, causing diabetic neuropathy. Exactly why this happens isn't completely clear, but a combination of factors likely plays a role, including the complex interaction between nerves and blood vessels. High blood glucose interferes with the ability of the nerves to transmit signals. It also weakens the walls of the small blood vessels (capillaries) that supply the nerves with o xygen and nutrients. Other factors Other factors that may contribute to diabetic neuropathy include: •
•
•
Inflammation in the nerves caused by an autoimmune response. This occurs when your immune system mistakenly attacks part of your body as if it were a foreign organism. Genetic factors unrelated to diabetes that make some people more susceptible to nerve damage. Smoking and alcohol abuse, which damage both nerves and blood vessels and significantly increase the risk of infections.
Risk factors By Mayo Clinic staff
Anyone who has diabetes can develop neuropathy, but these factors make you more susceptible to nerve damage: •
•
Poor blood sugar control. This is the greatest risk factor for every complication of diabetes, including nerve damage. Keeping blood sugar consistently within your target range is the best way to protect the health of your nerves and blood vessels. Length of time you have diabetes. Your risk of diabetic neuropathy increases the longer you have diabetes, especially if your blood sugar isn't well controlled. Peripheral neuropathy is most common in people who have had diabetes for at least 25 years.
•
•
Kidney disease. Diabetes can cause damage to the kidneys, which may increase the toxins in the blood and contribute to nerve damage. Smoking. Smoking narrows and hardens your arteries, reducing blood flow to your legs and feet. This makes it more difficult for wounds to heal and damages the integrity of the peripheral nerves.
Complications By Mayo Clinic staff
Diabetic neuropathy can cause a number of serious complications, including •
Loss of a limb. Because nerve damage can cause a lack of feeling in your feet, cuts and sores may go unnoticed and eventually become severely infected or ulcerated — a condition in which the skin and soft tissues break down. The risk of infection is high because diabetes reduces blood flow to your feet.
Infections that spread to the bone and cause tissue death (gangrene) may be impossible to treat and require amputation of a toe, foot or even the lower leg. More than half the nontraumatic lower limb amputations performed every year in the U nited States are due to diabetes. •
•
•
•
•
Charcot joint. This occurs when a joint, usually in the foot, deteriorates because of nerve damage. Charcot joint is marked by pain, as well as swelling, instability and sometimes deformity in the joint itself. Urinary tract infections and urinary incontinence. Damage to the nerves that control your bladder can prevent it from emptying completely. This allows bacteria to multiply in your bladder and kidneys, leading to urinary tract infections. Nerve damage can also affect your ability to feel when you need to urinate or to control the muscles that release urine. Hypoglycemia unawareness. Normally, when your blood sugar drops too low — below 70 milligrams per deciliter (mg/dL), or below 3.9 millimoles per liter (mmol/L) — you develop symptoms such as shakiness, sweating and a fast heartbeat. These symptoms alert you to the problem so that you can take steps to raise your blood sugar quickly. Autonomic neuropathy can interfere with your ability to notice these symptoms. This is extremely serious — untreated hypoglycemia can be fatal. Low blood pressure. Damage to the nerves that control circulation can affect your body's ability to adjust blood pressure. This can cause a sharp drop in pressure when you stand after sitting (orthostatic hypotension), which may lead to dizziness and fainting. Digestive problems. Damage to the nerves in the digestive system can cause a range of problems, including severe constipation or diarrhea — or alternating bouts of constipation and diarrhea — as well as nausea, vomiting, bloating and loss of appetite. One particularly serious digestive problem is gastroparesis, a condition in which the stomach empties too slowly or not at all. This can interfere with digestion, cause nausea and vomiting, and severely affect blood sugar levels and nutrition.
•
•
•
Sexual dysfunction. Autonomic neuropathy often damages the nerves that affect the sex organs, leading to erectile dysfunction in men and problems with lubrication and arousal in women. Increased or decreased sweating. When the sweat glands don't function normally, your body isn't able to regulate its temperature properly. A reduced or complete lack of perspiration (anhidrosis) can be life-threatening. Autonomic neuropathy also causes excessive sweating, particularly at night. Social isolation. The pain, disability and embarrassment caused by nerve damage can rob people — particularly older adults — of their independence, leaving them increasingly isolated and depressed.
Tests and diagnosis By Mayo Clinic staff
Diabetic neuropathy is usually diagnosed based on your symptoms, your medical history and a physical exam. During the exam, your doc tor is likely to check your muscle strength and tone, tendon reflexes, and sensitivity to touch, temperature and vibration. Other tests that may be conducted include: •
•
•
•
•
Filament test. Sensitivity to touch may be tested using a soft nylon fiber called a monofilament. If you're unable to feel the filament on your feet, it's a sign that you've lost sensation in those nerves. Nerve conduction studies. This test measures how quickly the nerves in your arms and legs conduct electrical signals. It's often used to diagnose carpal tunnel syndrome. Electromyography (EMG). Often performed along with nerve conduction studies, electromyography measures the electrical discharges produced in your muscles. Quantitative sensory testing. This noninvasive test is used to assess how your nerves respond to vibration and changes in temperature. Autonomic testing. If you have symptoms of autonomic neuropathy, your doctor may request special tests to look at your blood pressure in different positions and assess your ability to sweat.
The American Diabetes Association recommends that all people with diabetes have a comprehensive foot exam — either by a doctor or by a foot specialist (podiatrist) — at least once a year. In addition, your feet should be checked for sores, cracked skin, calluses, blisters, and bone and joint abnormalities at every office v isit. If you already have diabetic neuropathy, you'll likely be referred to a podiatrist or other specialist for monitoring and treatment.
Prevention By Mayo Clinic staff
You can help prevent or delay diabetic neuropathy and its complications by keeping your blood sugar consistently well controlled, taking good care of your feet and following a healthy lifestyle. Blood sugar control Keeping your blood sugar tightly controlled every day is a big commitment. It requires constant monitoring and, if you take insulin, frequent d oses of medication. But keeping your blood sugar as close to normal as possible is the best way to help prevent neuropathy and other complications of diabetes. Consistency is important because shifts in blood sugar levels can accelerate nerve damage.
For the best control, aim for a blood glucose level from 70 to 130 mg/dL (3.9 to 7.2 mmol/L) before meals and an A1C reading that is less than 7 percent. An A1C test measures your average blood sugar level over a period of two to three months. The American Diabetes Association recommends that people with diabetes have an A1C test at least twice a year if blood sugar levels are consistently in a healthy range. If your blood sugar isn't well controlled or you change medications, you should be tested more often. Foot care Foot problems, including sores that don't heal, ulcers an d even amputation, are a common complication of diabetic neuropathy. But many of these problems can be prevented by having a comprehensive foot exam at least once a year, having your doctor check your feet at each office visit and taking good care of your feet at home.
To protect the health of your feet: •
•
•
•
•
Check your feet every day. If you can't see some parts of your feet, use a mirror or ask a family member or friend to examine those areas. Look for blisters, cuts, bruises, cracked and peeling skin, and redness and swelling. Keep your feet clean and dry. Wash your feet every day with lukewarm water. If your feet can't sense temperature, test the water by touching a dampened washcloth to a sensitive part of your body, such as your neck or wrist. Dry your feet gently by blotting or patting. Rubbing may damage your skin. Dry carefully between your toes. Then moisturize your skin thoroughly to prevent cracking. Try to avoid getting lotion between your toes, however, as this can encourage fungal growth. Trim your toenails carefully. Cut your toenails straight across, and file the edges carefully so there are no sharp edges. If you're not able to reach your feet, ask a family member, your doctor or a podiatrist to help you. Wear clean, dry socks. You don't need to buy special socks for people with diabetes, but do look for socks made of cotton or moisture-wicking fibers that don't have tight bands or thick seams. Wear cushioned shoes that fit well. Always wear shoes to protect your feet from injury. Make sure that your shoes fit properly. It's best to try on shoes later in the day when your feet are more swollen to ensure that the shoes aren't too tight. A podiatrist can teach you how to buy properly fitted shoes and to prevent problems such as corns and calluses.
If problems do occur, a podiatrist can help treat them to prevent more-serious conditions from developing. Even small sores can quickly turn into severe infections if left untreated. Shoes that fit well can be costly. If you qualify for Medicare, your plan may cover the cost of at least one pair of shoes a year. For more information, talk to your doctor or diabetes educator. March 17, 2010
Medifocus Guidebook on Peripheral Neuropathy Updated: June 22, 2011 169 Pages Medifocus, Inc. 11529 Daffodil Lane, Suite 200, Silver Spring, MD 20902 Phone: 800.965.3002/301.649.9300 FAX: 301.649.7809 Email:
[email protected]
What is Peripheral Neuropathy? The nervous system controls the smooth functioning of all systems in the body as well as all interactions between the human being and the environment. The nervous system is comprised of millions of neurons that are interconnected and form a communications network within the body that governs many vital functions including: •
The five senses (sight, hearing, touch, smell, and taste)
•
Voluntary functions (e.g. walking, holding an object)
•
Involuntary functions (e.g. breathing, blood pressure)
•
Cognitive reasoning
The human nervous system has two major components: •
Central nervous system - includes the brain and spinal cord
•
Peripheral nervous system - includes the nerves that lead from the brain and spinal cord to all parts of the body. An extensive system of specialized nerves makes up the peripheral nervous system which is responsible for a variety of important functions. These specialized nerves include: o
motor nerves which carry messages from the brain to the body and are
responsible for the ability to move any part of the body (e.g., hands, feet) o
sensory nerves which carry information from organs to the central
nervous system where it is processed into sensation (e.g., touch, temperature changes, and vibrations) o
nerves that control autonomic (involuntary) functions including heart rate, blood pressure, breathing, digestion, and bladder function
Peripheral neuropathy is a term used to describe damage to nerves of the peripheral
nervous system which leads to symptoms such as pain, numbness, tingling, burning, and weakness most commonly affecting the hands and feet. Peripheral neuropathy can be caused by a variety of precipitating factors including trauma, infection, diabetes, alcohol abuse, and cancer chemotherapy. The incidence of peripheral neuropathy is not known with any degree of certainty. It has been estimated that approximately 2 to 3 million Americans have some form of peripheral neuropathy. The prevalence of peripheral neuropathy worldwide has been estimated to range from 2% to 8% of the population. Peripheral neuropathy affects both genders at all ages but symptoms are unique to each individual in terms of
frequency, quality, and severity of pain. Idiopathic peripheral neuropathy typically affects adults over the age of 50. Peripheral neuropathy can significantly impact an individual's quality of life and daily activities by causing major disruptions including: •
Sleep disturbances
•
Mood changes
•
Impairment of social, occupational, and recreational functioning
Knowledge is Critical when Dealing with a Life-Altering Condition such as Peripheral Neuropathy If you or a loved one has been diagnosed with peripheral neuropathy, it's critical to learn everything you possibly can about this condition so that you can make
