Neuropathy is a common condition impacting 60 to 70 percent of adults with diabetes. However, it mainly concerns those with uncontrolled blood sugar levels or those who have had diabetes for more than 25 years.
The nerve damage caused by diabetic neuropathy is irreversible but there are ways to lessen symptoms and prevent further harm.
What is diabetic neuropathy?
Neuropathy most commonly affects the feet and legs, causing pain and numbness.
Diabetic neuropathy is a family of progressive nerve disorders related to type 1 and 2 diabetes.
Although research is still taking place on this type of nerve damage, doctors think that blood sugars may damage nerve cells by impairing nerve fibers and reducing or confusing signaling.
However, nerve damage is likely to be caused by a combination of factors, such as how the immune system functions, genetics, smoking, or alcohol use.
Neuropathy can cause a range of symptoms, including pain, loss of sensation, numbness, tingling, and muscle weakness.
Although neuropathy can occur wherever there are nerves, it tends to affect the legs and feet.
Those with diabetic neuropathy tend to:
- have poor blood sugar control
- be over the age of 40
- be overweight or obese
- have high cholesterol
- have high blood pressure
- have had diabetes for at least 10 to 25 years, depending on the severity
Diabetic neuropathy is typically divided into four categories depending on which nerves are affected.
Nerve damage that impacts the ability of the peripheral nerves to sense things, such as temperature and touch.
Peripheral neuropathy most commonly affects the arms, hands, legs, feet, and toes, often causing pain or loss of feeling. It is the most common form of diabetic neuropathy.
Nerve damage resulting in pain in the hips, thighs, pelvis, and buttocks. Muscle weakness and pain in the legs are also a common symptom of proximal neuropathy.
Damage to a specific nerve or group of nerves anywhere in the body. Focal neuropathy often causes intense, sudden muscle weakness, pain, and loss of feeling.
Damage to the nerves that control involuntary organ control. Autonomic neuropathy can impact a range of crucial bodily functions, such as heart and breathing rate, gastrointestinal activity, sexual response, and blood pressure.
Many people with autonomic neuropathy lose the ability to detect when their blood sugars have dropped to dangerously low levels.
The best way to manage neuropathy is to lower or stabilize blood sugar levels.
Once neuropathy has occurred, there is no way to reverse it. However, there are lifestyle changes, therapies, and medications that can help lessen symptoms and prevent further nerve damage.
Lowering or stabilizing blood sugars is the first line of treatment recommended for diabetic neuropathy, and it is also the easiest and most efficient.
Maintaining steady blood sugar levels helps to ease neuropathy symptoms, such as pain and reduces the chances of further nerve damage by 50 percent.
Quitting smoking can also help. Smoking damages the walls of the arteries causing fat to build up, narrowing blood vessels, and making circulation harder. Poor circulation is a major contributing factor of neuropathy.
Other commonly recommended lifestyle tips to help treat diabetic neuropathy include:
- Taking diabetic medications correctly: Consistency and monitoring are essential to ensuring medications work as they are intended whether using insulin or metformin.
- Reducing alcohol consumption: Alcohol can cause spikes and dips in blood sugars contributing to uneven blood sugars and often counteracting medications. Alcohol also contains empty calories that can contribute to being overweight.
- Losing weight if necessary: Excess weight can lead to decreased insulin sensitivity and high blood sugars. Being overweight also increases the likelihood of developing diabetic neuropathy.
- Choosing healthful fats: Nuts, legumes, vegetable oils, low-fat dairy products, lean meats, and poultry products contain fats that the body knows how to process, use, and remove. Manufactured or added fats, often known as trans fats, are stored instead of used, often leading to high cholesterol and weight gain.
- Avoiding excess sugars: Highly refined or processed sugars, such as high glucose or fructose sweeteners, can cause sharp, sudden spikes in blood sugars followed by dips. Avoiding these highs and lows is key to proper blood sugar management and preventing further nerve damage.
- Treating other health complications: Health conditions that impact blood sugars, blood pressure and flow, or nerve control can increase the likelihood of developing neuropathy. Typical examples include heart, liver, and kidney disorders.
- Exercising: Regular exercise helps keep blood sugars steady, lower cholesterol, improve muscle efficiency and stamina, and improve blood flow. Getting 150 minutes of exercise weekly, ideally divided into five 30-minute sessions, is recommended.
- Professionally performed therapies: A wide range of therapies may help lessen neuropathy pain, improve blood flow, and reduce the chances of muscle wasting. These include massage, physical therapy, acupuncture, and chiropractor adjustments.
Peripheral neuropathy makes the feet and hands more vulnerable to damage and also causes a loss of sensation, making wounds easier to miss. People with diabetes should check their feet nightly for wounds or skin changes and keep feet as clean as possible. Toenails should be kept trim to avoid irritating or cutting foot skin.
People should avoid habits that expose their feet to damage, irritants, or germs, such as walking barefoot or sharing hygiene tools.
Those who experience any unusual, persistent, or worrying symptoms should visit a doctor. Regular, consistent foot care can help reduce the likelihood of amputation by 45 to 85 percent.
Over-the-counter pain medications often help ease nerve pain. For more severe cases, doctors may prescribe more concentrated, specified medications.
Everyone who takes pain medications should exercise caution, but people with blood pressure or bleeding conditions should be particularly careful. If people experience any worrisome symptoms, they should see their doctor.
Commonly used drug options used to treat diabetic neuropathy include:
- opioids, such as morphine sulfate, tramadol, oxycodone, and dextromethorphan
- antidepressants, such as venlafaxine, amitriptyline, and duloxetine hydrochloride
- anticonvulsants, such as pregabalin and sodium valproate
- topical treatments, such as capsaicin creams, isosorbide dinitrate sprays, and lidocaine patches
Some forms of electrical nerve stimulation, such as transcutaneous electrical nerve stimulation (TENS), are approved by the American Academy of Neurology (AAN) for the treatment of painful diabetic neuropathy.
Though there is some evidence for the use of magnetic, laser, and light therapy to reduce or control nerve pain, the AAN do not currently recommend these therapies.
Without treatment, the health complications caused and made worse by diabetic neuropathy can be severe.
Diabetic neuropathy can prevent wounds from healing and even cause gangrene in severe cases.
Some complications include:
- pain, stiffness, or soreness
- unawareness of low blood sugar
- nausea and vomiting
- impaired sense of hunger
- diarrhea and constipation
- impaired sexual function
- hand, leg, and feet infections or wounds that will not heal
- joint damage, especially to the feet and legs
- bladder control or urinary problems
- excessive or lack of sweat
- muscle atrophy
- gangrene or amputation, most commonly of the feet or legs
- low blood pressure
Advances in treatment
Researchers continue to investigate why and how diabetic neuropathy occurs, hoping to develop more precise treatment options.
Nearly all of the drug options used to treat the condition were not actually designed to target neuropathic pain. Most current medications also come with unpleasant side effects and carry a risk of dependency.
Most of the recent research into diabetic neuropathy treatment revolves around blocking or altering pain signals.
A 2015 study found that blocking hyperpolarization-activated cyclic nucleotide-gated (HCN) channels in rats drastically reduced the perception of pain in the region of the brain most often involved in processing pain signals.
Spinal cord simulation (SCS) therapies are also being explored. A 2016 study using rodents found that early, repetitive SCS might help reduce and reverse neuropathy pain by stimulating the endocannabinoid system and activating CB1 receptors.
Medications targeting molecules attached to the surface of nerve cells called gangliosides have long been studied as a potential cure for neurodegenerative disorders. Gangliosides have been shown to influence the brain's ability to form new nerve connections.
A research article from 2016 concluded that the depletion of one specific ganglioside called GM3 improved wound healing and fully reversed neuropathic pain in mice.