Some persons with diabetes have trouble feeling their feet or experience strange burning or tingling sensations due to damage to the long nerves that extend from the brain and spinal cord to various parts of the body. Damage to these long nerves, known as “peripheral neuropathy,” is the most commonly reported type of nerve damage among patients with diabetes.
- Numbness, burning, or a “pins and needles” feeling, usually in both feet
- Left untreated, nerve damage can progress to other parts of the body, often the hands
- Feet are affected before the hands
About one quarter of all persons with diabetes have symptoms, but more sensitive nerve testing would probably reveal peripheral neuropathy in more than half of all persons with diabetes.
Patients are more likely to develop nerve damage if they’ve had diabetes for many years, smoke, or have poorly controlled blood glucose, high blood pressure, or high cholesterol. It is important to manage these other medical conditions to reduce the chances of developing neuropathy in people with diabetes.
Though not very common, some patients complain of numbness in their feet—a symptom of peripheral neuropathy—before diabetes has developed when glucose levels are high but not yet in the diabetic range, a condition called prediabetes.
Patients who have trouble feeling their feet are less likely to notice injuries, callouses, or ulcers until a serious infection develops. This can lead in severe cases to amputations. These patients should check their feet for signs of injury every day.
Simple office tests with tuning forks and monofilaments assess whether the patient can feel vibrations or sharp sensations in the feet. A more sophisticated test, called a nerve conduction study, measures how well the nerves convey information from the brain to the feet.