You've heard about diabetic neuropathy before. You've probably been told (over and over) by your doctor that it's a leading complication in unmanaged diabetes.
But what is it, exactly, and what does it mean for you?
Neuropathy From Diabetes
Hyperglycemia (high blood sugar levels) damages nerves through a variety of mechanisms (high AGE products, sorbitol, oxidative stress, decreased blood flow, etc). 😱
Diabetic polyneuropathy -- what many know as diabetic neuropathy -- (numbness, tingling, and pain) is the most common presentation of nerve damage caused by hyperglycemia. It’s also the most common complication of diabetes. Not only that, it’s the most common form of neuropathy in general.
Other types related specifically to diabetes include mononeuropathy (only one nerve is damaged) or radiculopathy (several spinal cord nerve roots are damaged).
Diabetic neuropathy is symmetrical and bilateral nerve damage that starts in the feet and works its way up.
This nerve damage can lead to calluses, pressure ulcers, and wounds, which can lead to gangrene, and amputations. Neuropathy of other sensory or motor nerves is less common, but possible.
A side note on those calluses.
Lots of things can cause calluses! But nerve damage in your feet means that your brain can’t constantly keep subconsciously adjusting where you put pressure on your feet, first leading to calluses and then to pressure ulcers.
Your doctor should be -- and probably is -- checking for calluses as part of your regular foot exams, even if they aren’t telling you about it. If you’re worried they’re not, just ask them to take a look!
Neuropathy can also affect autonomic nerves, the ones that do the stuff we don’t think about.
Damage to these nerves can cause gastroparesis (nausea, vomiting, and early satiety), chronic diarrhea, poor glucagon response to low blood sugar, low blood pressure after standing or meals, high blood pressure when lying down, problems with sweating, itching, swelling, joint fractures, dry skin, sleep apnea, and so much more.
Also, damage to cardiac nerves can make it harder to detect symptoms of heart attacks, and is associated with high mortality.
Of course, lots of other problems can cause all of these symptoms. So if you feel like you’re experiencing any of them, be sure to talk to your doctor to figure out the root cause.
Diabetic Neuropathy: Type 1 Diabetes & Type 2 Diabetes
Neuropathy is actually much less common in type 1 diabetes than in type 2 diabetes. And the incidence of neuropathy in people with type 1 diabetes is decreasing, mostly due to advancements in treatment so that “intensive insulin therapy” is now the norm.
Intensive therapy decreases the incidence of neuropathy by up to 70% in people with type 1 diabetes and has been shown to delay, reduce, and improve symptoms!
What exactly does intensive therapy look like? Having an average A1c of 7.2% versus 9.2% from using intensive therapy. Then, continuing to intensify the treatment so that the A1c decreases from 7.2% to 6.3%, and so on.
Interestingly, a decrease in A1c doesn’t often help neuropathic symptoms for people with type 2 diabetes. Features of metabolic syndrome (elevated triglycerides, BMI, HTN) and other vascular risks like smoking are associated with progression of neuropathy and failure to improve despite good blood sugar management.
While these factors are commonly associated with type 2 diabetes, studies show the risks mentioned above progress neuropathy regardless of diabetes type. It’s likely that treating these factors will also help neuropathy (though there aren’t studies)!
This is why it’s so important - crucial - for those of us with diabetes to take care of our whole selves, not just the blood sugar levels.
How can you figure out if you have diabetic neuropathy? Doctors will usually run a sensory test at every visit. It can be something as simple as scratching a pen on the arch of your foot or pressing a tuning fork against your toe.
These noninvasive tests are used to measure your sense of touch and are a good indicator of the presence of (or lack thereof) neuropathy.
Prevention is always the best medicine. But if you have neuropathy, talk to your doctor. There are things we can do to help!