Sometimes a nerve conduction test may be needed to see whether certain nerves are affected, such as those in the arms or legs.
This is done by attaching special electrodes to the skin over the nerve being tested.
Another test is electromyography, which looks at the electrical activity of muscles.
This is done by inserting a very thin needle with an electrode attached into the muscle being tested; the way the muscle responds is recorded on an oscilloscope.
Not as common are nerve and skin biopsies, in which a small part of the suspect nerve is removed and examined under a microscope to detect damage.
Is there a connection between food and peripheral neuropathy?
Yes, some studies indicate that there may be connections between food and the occurrence of peripheral neuropathy. The following are two of these possible connections (for more about food, see the chapter “Diabetes and Food”):
• Several studies indicate that high glucose levels after a meal are strongly associated with peripheral neuropathy.
According to the Foundation for Peripheral Neuropathy, the best way to reduce after-meal glucose levels is to eat more foods that are slowly absorbed into the bloodstream.
These include fruits, vegetables, beans, and nuts, and not refined starches and sugars.
In addition, exercising after a meal will often cause blood glucose levels to decrease, and using fast-acting insulin can lower sugar.
The best way to discover how to lower levels after meals is for a person to work with his or her health care professional to make certain medical and/or eating adjustments.
• Another culprit that connects food and peripheral neuropathy is inflammation.
In fact, many foods are known to increase the amount of inflammation in the body.
The greatest problem in determining how a food affects a person is just that, different foods cause different inflammations in different people.
Some of the more well-known foods that can cause inflammation are trans fats, saturated fats, sugar, alcohol, and what are called omega-6 oils: corn, safflower, and soybean oils. (For more about omega-6, see the chapter “How Diabetes Affects the Digestive System.”) Of course, other types of food, such as those that contain dairy, nuts, caffeine, and other foodstuffs, can also cause inflammation.
To understand which foods may cause inflammation may take time.
Again, the best way to uncover foods that cause inflammation is to work with an individual’s health care professional.
Why does having diabetes often increase the risk for amputations?
For some people with diabetes, there is an increased risk for amputation.
This can be because of diabetic peripheral neuropathy but may also be from the complication of peripheral artery disease, or PAD.
Both conditions raise the risk for nerve damage.
If the damage is severe enough, it can eventually lead to amputation, especially if the tissue dies, and the extremity becomes infected.
This often happens with the feet as foot injuries and ulcers may not be readily noticed because of nerve damage.
What are some statistics concerning diabetes and amputations?
According to Harvard Medical School, diabetes is responsible for more than 60 percent of lower limb amputations that have not been caused by accidental injuries.
The school also notes that a person with diabetes is ten times more likely to have an amputation than a person who does not have diabetes.
But not everyone with diabetes will need amputation of extremities, especially if people keep their blood sugar levels under control and especially check their feet daily for possible cuts and wounds.
If there is a wound, tend to it immediately so it does not become infected.
THE BRAIN AND DIABETES
Why do human brain cells need glucose?
While most of the cells in the body can adapt, at least temporarily, to using lipids (fats) and proteins as energy sources, the human brain cells require glucose in order to work well. In fact, the brain cells can get energy only from glucose. This means that when the body’s blood glucose levels fall too low for that person, his or her brain cells shut down. This shutdown often results in fainting, which actually increases the flow of blood and glucose to the brain to compensate.
Can diabetes contribute to short- and long-term memory loss?
Short-term memory loss and reduced brain function can occur during periods of low and high blood glucose (hypoglycemia and hyperglycemia, respectively). Over the long term, high blood glucose (hyperglycemia) can affect memory in people with type 1 and type 2 diabetes. This is because high glucose levels can damage nerves, including those of the brain, thereby increasing the risk of memory loss, and sometimes eventually contribute to dementia.
What are the two forms of dementia most often mentioned in the media?
The term “dementia” describes a group of symptoms caused by changes in a person’s brain function and is usually associated with advancing age. The two most common forms of dementia in older people, and the ones most often mentioned in our daily lives, are multi-infarct dementia (sometimes called vascular dementia) and Alzheimer’s disease. These types of dementia are irreversible, which means they cannot be cured. Research on both types now center on mitigation or slowing down their progression.
In multi-infarct dementia, a series of small strokes or changes in the brain’s blood supply may result in the death of brain tissue.
The location in the brain where the small strokes occur determines the seriousness of the problem and the symptoms that arise.
Symptoms that begin suddenly may be a sign of this kind of dementia.
People with multi-infarct dementia are likely to show signs of improvement or remain stable for long periods of time, then quickly develop new symptoms if more strokes occur.
In many people with multi-infarct dementia, high blood pressure is to blame.
In Alzheimer’s disease, nerve cell changes in certain parts of the brain result in the death of a large number of cells.
The most common symptoms range from mild forgetfulness to serious impairments in thinking, judgment, and the ability to perform daily activities.
What is the possible connection between diabetes, Alzheimer’s disease, and something called “type 3 diabetes”?
In 2005, research suggested that there may be something called “type 3 diabetes,” or a term proposed for Alzheimer’s disease, which is thought to result (in part) from the brain’s resistance to insulin. Other studies followed, including several in 2012, indicating that resistance to insulin, and resulting low levels of insulin in the brain, seemed to play a key role in the progression of Alzheimer’s disease. Another study indicated that people with insulin resistance, especially those with type 2 diabetes, have an increased risk of eventually developing Alzheimer’s disease, between 50 and 60 percent higher than people without type 2 diabetes.
Most researchers emphasize that not everyone with type 2 diabetes develops Alzheimer’s disease, but type 2 could be a co-factor in the disease’s progression. (In other words, having type 2 diabetes does not cause Alzheimer’s disease but may contribute to an increase in impaired brain function and eventually Alzheimer’s.) Other researchers suggest that diabetes and Alzheimer’s disease may have the same source: An overconsumption of foods that cause problems with the many roles insulin plays in the body.
And since such consumption often leads to obesity, several studies indicate that as the obesity rates have increased in the past several decades, so has the incidence of Alzheimer’s disease.
More studies need to be done.
If there is a definite connection, some “cures” for type 2 diabetes and Alzheimer’s may be as “simple” as eating the right foods, exercising, and keeping off excess weight.
The Handy Diabetes Answer Book
HOW DIABETES AFFECTS THE CIRCULATORY SYSTEM
What are the main components of the circulatory system?
The main components of the circulatory system are the vessels, heart, and blood. The system also includes a person’s blood pressure, as blood pressure involves the blood pumping through the body, and how it affects the heart and blood vessels.
What is a pulse?
A person’s pulse is the alternate expansion and recoil (contraction) of an artery, which can be felt in an artery close to the body’s surface.
The pulse occurs because of the rhythmic ejection of blood from the heart into a main artery called the aorta, which causes an increase and decrease of pressure in the artery.
The pulse provides important information about the heart action, blood vessels, and circulation.
For example, a fast pulse rate may indicate the presence of dehydration.
And of course, in a medical emergency, a pulse will help determine whether a person’s heart is pumping.
DIABETES AND THE HEART
In general, how does the human heart work?
The human heart (a muscle), located beneath the upper-left portion of a person’s torso, is about the size of a clenched fist.
On average, the heart beats about 70 to 75 times per minute (resting) and pumps about five quarts (just over five liters) of blood per minute.
Within the heart, two atria receive blood, while two ventricles pump blood out of the heart.
The heart also has a natural “pacemaker,” called the sinoatrial node, or the part of the heart that times the contraction by generating and sending electrical signals to what is called the atrioventricular node.
The impulses are sent to certain fibers, causing the ventricles to contract.
These electrical impulses are also what are detected by an electrocardiogram (EKG) many people receive to check for irregularities in the heartbeat.
Several factors can affect the heart’s pacemaker, including two sets of nerves that speed up or slow down the heart, the release of hormones such as adrenaline, and the body’s overall temperature.
Does having diabetes increase the risk of heart disease?
Yes, for most people, diabetes increases the risk of heart disease.
In fact, according to the National Institutes of Health, at least 65 percent of people with diabetes die of some form of heart or blood vessel disease.
Other research indicates that type 2 diabetes is associated with a two- to fourfold excess risk of cardiovascular disease.
This includes such conditions as elevated triglyceride levels and a decrease in HDL (the “good” cholesterol) levels. (For more about triglycerides and cholesterol, see this chapter.)
What is atrial fibrillation?
Atrial fibrillation, often referred to as afib, is the most common abnormal heart rhythm reported.
It is estimated that about 1 in 100 people, around 5 in 100 over age 65, and around ten in 100 people over age 80 have this condition.
It occurs when the heart beats irregularly in comparison to a normal heartbeat.
The symptoms often include heart palpitations, fainting, fatigue, or congestive heart failure.
It can also make the blood “pool” within certain heart chambers, causing the heart to “quiver” in a chaotic pattern, which slows the blood flow and creates irregular beats.
If the pooled blood stagnates, it can sometimes cause clots to form, which can lead to embolic strokes.
Atrial fibrillation is thought of as a problem with the heart’s “electrical control,” mainly a group of cells called the sinus node, also often referred to as the body’s natural pacemaker.
If for some reason, and many times, the reasons are difficult to diagnose, the electric signal has a problem, it can cause the heart to pump irregularly.
In atrial fibrilations, the electrical signals sent to the heart muscles are irregular, causing the atria (heart chambers) to not work well together. The resulting, fluttering heartbeat puts people at greater risk of heart attacks.