More than 16% of people with diabetes are known to have diabetic foot problems. A greater percentage of people are suffering from diabetic neuropathy. Diabetic neuropathy is a major reason for many diabetic foot diseases, cardiovascular diseases, and gastric conditions.
Most people are aware of diabetes, but not many are aware that diabetes can lead to lifelong nerve conditions. These nerve conditions can lead to a host of diabetes complications when diabetes is not managed properly.
In this section, we shall see what diabetic neuropathy is, its symptoms, treatment, and prevention.
What is diabetic neuropathy?
Diabetic neuropathy is a common condition among people with both diabetes type 1 and diabetes type 2. For many people, diabetic neuropathy surfaces even before the diagnosis of diabetes. It is said that 90% of people with diabetes suffer from diabetic neuropathy.
Diabetes is characterized by high blood glucose levels. Constant high blood glucose levels causes changes in the small blood vessels and nerves. High blood glucose levels tend to damage nerves from the cellular level and cause nerve fiber loss.
Added to that, cells of the small blood vessels are also damaged due to high blood sugar levels. These two factors lead to gradual destruction of the nerve cells leading to diabetic neuropathy of the peripheral nerves and the autonomic nerves.
Types of diabetic neuropathy
Diabetic neuropathy differs based on the type of nerves it affects. When diabetes affects the peripheral nerves (nerves outside the brain and spinal cord controlling sensory organs, muscles, and blood vessels), it leads to diabetic peripheral neuropathy.
When diabetes affects the autonomic nerves (nerves that regulate heart rate, respiration, digestion, kidney function, liver function, and sexual arousal), it leads to diabetic autonomic neuropathy.
In some cases, when there is damage to the sensory, motor, and autonomic nerves, it leads to a condition called diabetic polyneuropathy.
Diabetic peripheral neuropathy
High blood glucose can damage different types of nerves. When diabetes damages peripheral nerves, it leads to diabetic peripheral neuropathy. It affects one-third of all people with diabetes. This type of nerve damage is common in both type 1 and type 2 patients. Diabetic peripheral neuropathy can be painful.
Diabetic peripheral neuropathy is a progressive condition and the intensity of the disease increases with the duration of diabetes. In the initial stages, there might be no presence of diabetic peripheral neuropathy. Later, there might be signs of this condition, but with no symptoms (signs as perceived by the doctor).
As the duration of diabetes increases and when blood glucose control is not optimal, mild symptoms appear. Symptoms often appear in the form of diabetic foot pain, diabetic leg pain, and diabetic foot problems. Slowly, the severity of the symptoms increase and the patient reaches a condition of disability.
Diabetic autonomic neuropathy
Diabetic autonomic neuropathy is a serious condition that is present in many people with diabetes. This condition occurs when the autonomic nerves that regulate the function of heart, respiratory system, gastrointestinal system, kidneys, and other vital organs are affected by high blood glucose levels. People with poor blood sugar control and a higher duration of diabetes are prone to diabetic autonomic neuropathy.
Diabetic autonomic neuropathy can affect the heart leading to conditions like:
- Tachycardia (faster heartbeat)
- Heart valve diseases
- Diabetic cardiomyopathy
- Diabetic cardiovascular autonomic neuropathy
- Sudden cardiac death
When it comes to the gastrointestinal system, diabetic autonomic neuropathy leads to:
- Esophageal enteropathy
- Fecal incontinence
Diabetic autonomic neuropathy is also known to lead to erectile dysfunction, diabetic nephropathy and other conditions.
Risk factors for Diabetic neuropathy
Diabetic neuropathy is a condition in which there is nerve fiber loss due to high blood sugar levels and its action on the cells of nerves. The risk of diabetic neuropathy, both peripheral and autonomic, increases with:
- Poor control of diabetes
- High blood glucose levels
- Increasing age
- Duration of diabetes
- High blood pressure
- High cholesterol levels
- Improper foot care in diabetes
- Excess friction and pressure on feet
- Peripheral artery disease
Symptoms of autonomic neuropathy
- Feeling full despite eating less
- Nausea, vomiting
- Fast heartbeat
- Loss of control over urination
- Frequent urinary tract infections
- Sexual dysfunction
- Sweating too little or too much
If you have diabetes and experience any of these symptoms, consult an endocrinologist immediately.
Peripheral diabetic neuropathy symptoms
- Numbness of feet
- Sharp pain
- Tingling sensation
- Deformities as a result of loss of nerves in muscles
- Heat/burning sensation
- Formation of sores and blisters
Loss of blood flow and damage to the nerves lead to diabetic neuropathy affecting the farthest parts of the body, namely feet and hands. In most cases, feet are affected. Damage to the nerves of the feet leads to:
- Tingling sensation in the feet
- Loss of sensation
- Ulceration and infection
Diabetic foot problems lead to a range of conditions like diabetic foot pain, diabetic leg pain, and diabetic foot ulcers. These conditions can even lead to foot amputation if not managed properly.
Stages of Diabetic neuropathy of the feet
- Neuropathy without wounds, ulcers, or infections
- Diabetic foot infections
- Ischemia (inadequate blood supply to tissues of the feet)
- Ischemia and foot infection
How is diabetic neuropathy diagnosed?
Diabetic neuropathy is diagnosed either as part of a regular diabetes complication screening or when a person exhibits symptoms of diabetic neuropathy. Tests include:
Nerve tests like:
- Light touch and pinprick sensation
- Deep tendon reflex
- Tinel testing
- Cranial nerve testing
- Cardiovagal, adrenergic, and sudomotor function
Other tests including:
- HbA1c test
- Fasting blood glucose test
- Upright & supine blood pressure
- Heart rate test
- Nerve, skin biopsy
- Thyroid function test
- Complete blood count
- C-reactive protein
Depending upon the patient’s condition and past medical history, doctors may suggest tests like complete metabolic panel test, rheumatoid factor, and others.
Diagnosis of diabetic neuropathy of the feet
Diagnosis of diabetic neuropathy is done by testing plantar pressure distribution with tests like Podia Scan and Biothesiometry. These tests measure:
- Vibration perception
- Sensation in the feet with pin prick
- Presence of diabetic neuropathy
- Presence of peripheral vascular disease
- Risk of foot ulceration with pressure distribution on feet while walking
Diabetic neuropathy treatment
Treatment of diabetic neuropathy depends upon the intensity of nerve damage, the type of nerves damaged, and the presence of pain. One of the major aspects of treating diabetic neuropathy is gaining blood sugar control and control over diabetes. Treatment includes:
- Medical management including pain medication, and reduction of symptoms in autonomic neuropathy
- Prescription of anticonvulsants and antidepressants for pain relief
- Tight control over blood glucose levels
- Surgeries like pancreatic transplantation, penile prosthesis, or amputation depending upon the effect of the neuropathy
- Foot care with diabetic footwear and frequent follow up
How to Prevent Diabetic Neuropathy
Nerve damage starts much before the diagnosis of diabetes during the phase of impaired glucose tolerance. However, it is possible to control diabetic neuropathy.
- Reach target blood sugar levels & HbA1c
- Quit smoking
- Avoid alcohol
- Consider vitamin supplementation - B1, B6, & folate
- Get biofeedback or physical therapy
- Consider acupuncture
- Always wear diabetic footwear
- Examine feet regularly
- Avoid excess pressure and friction
If you are experiencing any kind of diabetic foot problems like diabetic foot pain, diabetic leg pain or foot ulcers, consult an endocrinologist immediately.