Neuropathy means pathology of the nerves or nerve damage. Diabetic neuropathy is nerve damage seen in patients with diabetes and prevails in about 70% of patients who have had diabetes for over 20 yrs. It is a nerve problem that causes pain, numbness, tingling, swelling, or muscle weakness in the affected part of the body.
There are four different types of diabetic neuropathies and each presents with a different set of symptoms. The exact cause is not yet ascertained though some risk factors make you prone to develop this diabetic condition.
It is believed to be caused due to reduced blood supply to the nerve or its segment, which occurs due to atherosclerosis, one of the complications of diabetes. This results in nerve damage and loss of nerve function.
What is Diabetic Neuropathy?
Blood vessels in a diabetic patient get clogged due to atherosclerosis and this results in reduced blood supply to the particular part of the body, which that blood vessel supplies.
When the blood vessel supplying blood to a particular nerve or its segment gets clogged, blood supply to that nerve gets drastically reduced or blocked. This results in reduced functioning of that nerve, giving rise to neuropathy.
Thus, depending on the site of the nerve, the symptoms present themselves. Usually, diabetic neuropathy damages the peripheral nerves of the lower extremities – the hands and feet. For a better prognosis, it is best to start treatment early, at the outset of symptoms
Diabetic neuropathy causes and risk factors
The exact etiology of diabetic neuropathy still remains unknown. However, it occurs in people with sustained uncontrolled high blood sugar levels over a long period of time.
There are various common risk factors though. Long-term exposure to high blood sugar levels destroys the delicate nerve fibers and weakens the walls of the capillaries, which supply blood and nutrients to the nerves.
Risk factors include:
- Metabolic causes such as long-standing diabetes and high levels of fats in the blood lead to diabetic neuropathy.
- Vascular causes result in damage to the blood vessels, which supply the nerve
- Damage to the nerve itself due to some external factors
- Smoking and Alcohol use causes damage to both the nerves and blood vessels
- In some persons, there is an inherent tendency for nerve weakness (genetic causes)
- Some autoimmune factors result in nerve weakness leading to neuropathy.
- Being overweight or obese increases your risk of diabetes and diabetic neuropathy
- Diabetes is known to cause kidney damage. This increases certain toxins in the blood, which can cause diabetic neuropathy.
Symptoms of diabetic neuropathy
There are four main types of diabetic neuropathy. You can develop one or more than one types.
Your symptoms will depend on the type of neuropathy you have and the nerves involved. Usually, symptoms develop gradually and are felt only after the nerve has suffered considerable damage.
Peripheral neuropathy is the most common type of diabetic neuropathy. It is also referred to as distal symmetric peripheral neuropathy. Up to about half of the people with diabetes suffer from peripheral neuropathy.
It affects the lower limbs initially and later the upper limbs. Signs and symptoms of peripheral neuropathy include:
- Pain in the limbs
- Tingling and numbness
- Inability or reduced ability to feel pain or temperature changes
- A burning sensation
- Increased sensitivity to touch — for some people, even a bedsheet’s weight can be painful
- Ulcers, infections, and bone pain in the feet
The autonomic nervous system regulates and controls involuntary functions such as the beating of the heart, maintaining blood pressure, respiration, digestion, eyesight, and sexual arousal.
Autonomic neuropathy is damage to nerves that control these internal organs caused by diabetes. This can affect nerves in any of these areas, giving rise to the following symptoms:
- Hypoglycemia unawareness – A lack of realization that blood sugar levels have dropped very low
- Bladder or bowel problems
- Nausea, vomiting, and loss of appetite due to slow stomach emptying (gastroparesis),
- Changes in the way your eyes adjust from light to dark
- Decreased sexual response
Proximal neuropathy (diabetic polyradiculopathy)
Proximal neuropathy — also called diabetic amyotrophy — often affects nerves in the thighs, hips, buttocks, or legs. It can also damage the nerves of the abdomen and chest. Symptoms usually appear on one side of the body but may spread to the other side. You may have:
- Severe pain in a hip and thigh or buttock
- Weak and wasting of thigh muscles
- Difficulty in rising up from a sitting position
- Severe abdominal pain
Mononeuropathy (focal neuropathy)
Mononeuropathy, also called focal neuropathy, is of two types — cranial and peripheral. In this type of neuropathy, a specific nerve is damaged. Symptoms may include:
- Difficulty focusing the eyes or there may be double vision
- Pain behind one eye
- Bell’s palsy – Paralysis on one side of your face
- Numbness or tingling in your hand or fingers
- Weakness in your hand that may cause you to drop things
- Symptoms of carpal tunnel syndrome