Diabetic Neuropathy

Diabetic neuropathy is nerve damage caused by diabetes that can affect up to half of all people living with the condition, causing pain, numbness, and other serious complications throughout the body.

Table of contents

• What is Diabetic Neuropathy?
• Types of Diabetic Neuropathy
• Causes and Risk Factors
• Symptoms
• How is Diabetic Neuropathy Diagnosed?
• Treatment Options
• Prevention and Self-Care

What is Diabetic Neuropathy?

Diabetic neuropathy is a type of nerve damage that happens when you have diabetes. Nerves are bundles of special tissues that carry signals between your brain and other parts of your body, helping you feel things, move your body parts, and control important body functions like digestion^[2]. When blood sugar levels remain high over time because of diabetes, this can injure nerves throughout the body^[1].

This condition is a serious health concern that may affect up to half of people who have diabetes^[1]. About half of all people with diabetes have some form of nerve damage^[3]. The condition is more common in those who have had diabetes for many years and can lead to various health problems, impacting quality of life^[3].

The good news is that diabetic neuropathy can often be prevented or slowed down. The key is to tightly manage blood sugar levels and lead a healthy lifestyle^[1].

Types of Diabetic Neuropathy

Diabetic neuropathy can damage different nerves throughout your body. There are four main types of diabetic neuropathy^[1][2]:

Peripheral Neuropathy

This is the most common type of diabetic neuropathy. Peripheral neuropathy typically affects the feet and legs first, followed by the hands and arms^[1]. About one-third to one-half of people with diabetes have this type^[6]. It causes damage to nerves outside of your spinal cord^[4].

Autonomic Neuropathy

Autonomic neuropathy is damage to nerves that control your internal organs and involuntary body processes^[4]. These nerves control things like your bladder, intestinal tract, blood pressure, heart, and sex organs. This type can lead to problems with your heart rate and blood pressure, digestive system, bladder, sex organs, sweat glands, eyes, and ability to sense when blood sugar is low^[2]. More than 30% of people with diabetes have autonomic neuropathy^[4].

Focal Neuropathies

Focal neuropathies are conditions in which you typically have damage to single nerves, most often in your hand, head, torso, or leg^[2]. The most common types of focal neuropathy are entrapment syndromes, such as carpal tunnel syndrome^[6].

Proximal Neuropathy

Proximal neuropathy is a rare and disabling type of nerve damage in your hip, buttock, or thigh^[2]. This type of nerve damage typically affects one side of your body and may rarely spread to the other side^[2]. The damage usually affects one side of the body, and symptoms gradually improve over a period of months or years^[6].

Causes and Risk Factors

Over time, high blood glucose levels, also called blood sugar, and high levels of fats, such as triglycerides, in the blood from diabetes can damage your nerves^[2]. High blood sugar levels over a long time are the main factor that damages your nerves^[7].

If you have diabetes, your chance of developing nerve damage increases the older you get and the longer you have diabetes^[2]. You are also more likely to develop nerve damage if you^[2]:

• Are overweight
• Have high blood pressure
• Have high cholesterol
• Have advanced kidney disease
• Drink too many alcoholic drinks
• Smoke

Research also suggests that certain genes may make people more likely to develop diabetic neuropathy^[2].

Symptoms

The symptoms depend on the type of diabetic neuropathy you have and which nerves are affected. Usually, symptoms appear slowly over time. You may not notice anything is wrong until a lot of nerve damage has happened^[1]. Up to 1 in 2 people with diabetic neuropathy do not have symptoms^[7].

Symptoms of Peripheral Neuropathy

Diabetic peripheral neuropathy commonly affects the feet. Symptoms often are worse at night and may include^[1][4]:

• Loss of feeling, also called numbness, or less ability to feel pain or temperature changes
• A tingling or burning feeling
• Sharp pains or cramps
• Muscle weakness
• Being very sensitive to touch—for some people, even a bedsheet’s weight can be painful
• Slow-healing leg or foot sores
• Total loss of sensation in your feet, like not feeling pain from foot injuries

Nerve damage that causes peripheral neuropathy typically develops over many years. You may not notice symptoms of mild nerve damage for a long time^[4].

Symptoms of Autonomic Neuropathy

Autonomic neuropathy can have many different symptoms because it can affect several body systems. Examples include^[4][7]:

• Digestive system: Bloating, heartburn, indigestion, nausea and vomiting, gas, diarrhea, or constipation
• Urinary system: Problems with urinating, urinary incontinence, urinary retention, and frequent urinary tract infections
• Sex organs: Sexual dysfunction, erectile dysfunction, vaginal dryness, and problems with sexual function
• Cardiovascular system: Low blood pressure, irregular heart rate, dizziness, and fainting
• Sweat glands: Heat intolerance, problems with sweating, excessive sweating, or a lack of sweat
• Eyes: Difficult for your pupils to adjust to changes in light

Autonomic neuropathy can also cause hypoglycemia unawareness. This means you don’t experience the typical warning signs of low blood sugar, like shakiness, confusion, and intense hunger^[4].

Symptoms of Proximal Neuropathy

Symptoms of proximal neuropathy include^[4]:

• Sudden and severe pain in your hip, buttock, or thigh
• Weakness in your leg that makes it difficult to stand

How is Diabetic Neuropathy Diagnosed?

To figure out if you have diabetic neuropathy, your healthcare professional gives you a physical exam. You’re also asked questions about your symptoms and medical history^[9].

During the exam, your healthcare professional most often checks^[9]:

• Your overall muscle strength and tone
• The reflexes of your muscles and tendons
• How sensitive you are to touch, pain, temperature, and vibration

Along with a physical exam, your healthcare professional may do or order certain tests. The tests can help confirm whether or not you have diabetic neuropathy. They may include^[9]:

• Filament testing: A soft nylon fiber called a monofilament is brushed over areas of your skin to check how sensitive you are to touch
• Sensory testing: This test is used to tell how your nerves respond to vibration and changes in temperature
• Nerve conduction testing: This test measures how quickly the nerves in your arms and legs conduct electrical signals
• Electromyography: Called needle testing, this test is often done along with nerve conduction studies. It measures electrical activity in your muscles
• Autonomic testing: Special tests may be done to determine how your blood pressure and heartbeat change while you are in different positions. The tests also can help identify whether your sweating is within the standard range

Treatment Options

Diabetic neuropathy has no known cure^[9]. The goals of treatment are to slow the disease from getting worse, relieve pain, manage health issues linked with diabetic neuropathy, and help the parts of the body affected by neuropathy work better^[9].

Managing Blood Sugar Levels

The key way to prevent or delay nerve damage is to keep your blood sugar within your target range^[9]. Good blood sugar control may even improve some of your current symptoms. Ensuring diabetes is well controlled may help improve neuropathy, or at least stop it getting worse^[15].

Medications for Pain Relief

Neuropathic pain does not usually get better with common painkillers, such as paracetamol and ibuprofen, and other medicines are often used^[15]. Pregabalin and duloxetine are the only medications approved by the U.S. Food and Drug Administration for treating diabetic neuropathy^[11].

The main medicines recommended for neuropathic pain include^[15]:

• Amitriptyline—also used for treatment of headaches and depression
• Duloxetine—also used for treatment of bladder problems and depression
• Pregabalin and gabapentin—also used to treat epilepsy, headaches, or anxiety

These medications should usually be started at the minimum dose, with the dose gradually increased until you notice an effect^[15]. The most common side effects are tiredness, dizziness, or feeling “drunk”^[15].

Additional Treatment Options

There are some additional medicines that you can take to relieve pain in a specific area of your body^[15]:

• Capsaicin cream and patch: Capsaicin is the substance that makes chilli peppers hot and is thought to work by stopping the nerves sending pain messages to the brain. Side effects can include skin irritation and a burning or itching sensation in the treated area^[15]
• Lidocaine patches: These can provide localized pain relief^[11]

Other Therapies

If you have muscle weakness, you may need physiotherapy to learn exercises to improve your muscle strength^[15]. You may also need to wear splints to support weak ankles or use walking aids to help you get around^[15].

Prevention and Self-Care

Although it might not always be possible to prevent neuropathy, a person with diabetic neuropathy might be able to minimize their symptoms by taking some precautions and making lifestyle adjustments^[17].

Keep Your Blood Glucose Levels in Your Target Range

Meal planning, physical activity, and medications, if needed, all can help you reach your target range^[18]. There are two ways to keep track of your blood glucose levels^[18]:

• Use a blood glucose meter or continuous glucose monitor to help you make decisions about day-to-day care
• Get an A1C test (a lab test) at least twice a year to find out your average blood glucose for the past 2 to 3 months

Check Your Feet Regularly

A person with diabetes should check their feet frequently to ensure that they spot any signs or symptoms of nerve damage or other complications of diabetes^[17]. Do a self-check every evening to look for foot problems—check the tops, soles, and between each toe. If you can’t easily see the bottom of your feet, use a mirror or ask someone to help^[19].

It is also important that they care for their feet, which may involve washing and moisturizing the feet, avoiding going barefoot, and wearing comfortable, well-fitting shoes^[17].

Exercise Regularly

Regular physical activity is crucial. Exercise helps improve blood flow to your nerves, which can reduce pain and promote healing^[19]. You don’t need to do intense workouts; simple activities like walking, swimming, or stretching can be very beneficial. Aim for at least 30 minutes of moderate exercise most days of the week^[19].

Maintain a Healthy Diet

Eating a balanced diet with healthy foods like fruits, vegetables, lean proteins, and whole grains can help you maintain stable blood sugar levels^[19]. A healthy, balanced eating plan helps stabilize glucose and manage diabetes^[21].

Don’t Smoke

Smoking is a risk factor for diabetic neuropathy. It increases your risk for dangerous foot problems with diabetes because of its harmful effects on circulation^[19].

Manage Other Health Conditions

Keep your blood pressure and cholesterol levels under control. High blood pressure and high cholesterol are risk factors for developing diabetic neuropathy^[2].