Diabetic Autonomic Neuropathy

Diabetic autonomic neuropathy is a serious complication of diabetes that affects the nerves controlling automatic body functions. It can impact your heart rate, blood pressure, digestion, bladder, sexual function, and more. Understanding this condition is essential for managing symptoms and maintaining quality of life.

Table of contents

• What Is Diabetic Autonomic Neuropathy
• Causes and Risk Factors
• How Common Is This Condition
• Signs and Symptoms
• How Doctors Diagnose the Condition
• Treatment and Management
• Prevention Strategies

What Is Diabetic Autonomic Neuropathy

Diabetic autonomic neuropathy is damage to the autonomic nerves caused by diabetes. These nerves control functions in your body that happen automatically, without you having to think about them^[1][2]. They manage things like your heartbeat, blood pressure, sweating, digestion, urination, and sexual function^[5].

When diabetes damages these nerves, the messages sent between your brain and other organs become disrupted. This can affect many different systems in your body, including your heart, blood vessels, digestive system, bladder, sex organs, sweat glands, and eyes^[2][4].

This type of nerve damage is a form of diabetic neuropathy, which is nerve damage that happens in people with diabetes. While diabetic neuropathy can affect different nerves throughout the body, autonomic neuropathy specifically damages the nerves that control involuntary body processes^[7][13].

Causes and Risk Factors

The main cause of diabetic autonomic neuropathy is having high blood sugar levels over a long period of time. When blood glucose stays elevated, it can damage your nerves and the small blood vessels that supply nutrients to your nerves^[4][7]. High levels of fats in the blood, such as triglycerides, can also contribute to nerve damage^[4].

Several factors can increase your risk of developing diabetic autonomic neuropathy. High blood pressure is one important risk factor^[21]. Being overweight and smoking also raise your risk^[5]. The longer you have had diabetes, the more likely you are to develop this type of nerve damage^[5].

Both people with type 1 diabetes and type 2 diabetes can develop autonomic neuropathy. Diabetes is the most common cause of autonomic neuropathy, though other health conditions, infections, and some medications can also cause it^[2].

How Common Is This Condition

Diabetic autonomic neuropathy is a common and serious complication of diabetes, though it often does not receive the attention it deserves despite its relationship to increased risk of death and its association with many symptoms and impairments^[1].

Studies show that more than 30% of people with diabetes have autonomic neuropathy^[7][13]. In randomly selected groups of people with diabetes who had no symptoms, approximately 20% had unusual cardiovascular autonomic function^[1].

The condition frequently occurs alongside other types of diabetic nerve damage and other diabetes complications. However, diabetic autonomic neuropathy may also occur by itself, often appearing before other complications can be detected^[1].

Signs and Symptoms

The symptoms of diabetic autonomic neuropathy vary depending on which nerves and body systems are affected. Many people with this condition experience problems in several different areas of the body^[2][9].

Heart and Blood Pressure Problems: Damage to the nerves controlling your heart and blood vessels can cause several issues. You may feel dizzy or faint when you stand up from lying down or sitting, a condition called orthostatic hypotension^[2][4]. Your heart rate may be rapid when you are resting, or it may suddenly speed up or slow down^[4][5]. Nerve damage can also prevent you from feeling chest pain during a heart attack, which doctors call a silent heart attack^[5].

Digestive System Problems: When autonomic neuropathy affects the nerves of your digestive system, you may experience bloating, fullness, and nausea^[4]. Other common symptoms include constipation, diarrhea (especially at night), problems swallowing, vomiting, and heartburn^[2][4]. The condition can also cause gastroparesis, a disorder that slows or stops the movement of food from your stomach to your small intestine^[4]. This can make it difficult for your body to absorb glucose and use insulin properly, making blood sugar control more challenging^[4].

Bladder Problems: Nerve damage affecting the bladder can make it difficult to know when you need to urinate and when your bladder is empty^[4][6]. This damage may cause you to hold urine for too long, which can lead to bladder infections. You may also experience urinary incontinence, urgency, or frequent urinary tract infections^[2][7].

Sexual Function Problems: Autonomic neuropathy can cause sexual difficulties in both men and women. Men may have problems achieving or maintaining an erection, known as erectile dysfunction, or problems with ejaculation^[2][6]. Women may experience vaginal dryness, low libido, and difficulty reaching orgasm^[2].

Sweating Problems: The nerves that control sweating can be damaged by autonomic neuropathy. Reduced sweating is common, especially in the hands and feet^[5]. Some people experience excessive sweating in the upper body, face, or neck, particularly at night or while eating hot or spicy food^[2][5]. Changes in your body’s ability to regulate temperature may make you more vulnerable to overheating or becoming too cold^[5].

Other Symptoms: Some people lose the ability to recognize when their blood sugar is dropping too low, a condition called hypoglycemia unawareness^[4][7]. This happens because the warning signals of low blood sugar, such as shakiness and sweating, are no longer present. Your pupils may also have difficulty adjusting to changes in light^[7].

How Doctors Diagnose the Condition

When you have risk factors for autonomic neuropathy and experience symptoms, your healthcare provider will perform a physical exam and ask about your symptoms^[8]. The specific tests needed depend on your symptoms and which body systems may be affected.

Cardiovascular Tests: Cardiovascular autonomic reflex tests are the gold standard for diagnosing heart and blood pressure problems related to autonomic neuropathy^[14]. These tests record how your heart rate changes in response to specific actions designed to trigger a sympathetic or parasympathetic response, such as paced breathing or the Valsalva maneuver (forcefully breathing out)^[8][14]. Doctors also measure changes in heart rate and blood pressure when you change position, such as from lying down to standing^[8].

Digestive System Tests: If gastroparesis is suspected, doctors may use special imaging studies that show how quickly your stomach empties^[8][14]. Gastric emptying tests can confirm this diagnosis.

Bladder Tests: To evaluate bladder problems, doctors may measure how much urine remains in your bladder after urination, called postvoid residual volume. They may also perform urodynamic testing to determine whether the bladder is underactive or overactive^[14].

Sexual Function Tests: The initial evaluation for erectile dysfunction involves determining whether the cause is psychological or physical in nature^[14].

Treatment and Management

There is no cure for diabetic autonomic neuropathy, but you can manage the condition and reduce symptoms through various approaches^[7]. Treatment focuses on optimizing blood sugar control and addressing specific symptoms^[14].

Blood Sugar Control: The key to preventing nerve damage from getting worse is keeping your blood sugar within your target range^[15][19]. Good blood sugar control may even improve some of your current symptoms. Your doctor will work with you to develop a plan for managing diabetes, which may include regular blood sugar monitoring, medication, a healthy diet, and exercise^[19].

Managing Blood Pressure and Heart Problems: If you experience dizziness when standing, several approaches can help. Simple physical actions can minimize symptoms, such as moving slowly between different body positions and sitting or lying down when symptoms begin^[10]. Drinking plenty of fluids and eating enough salt can also help, as can sleeping with your head elevated 15 to 20 degrees^[10]. Compression stockings that reach the thighs can provide benefit, though they may be difficult to put on^[10]. If these conservative measures do not work well enough, medications such as fludrocortisone, midodrine, and droxidopa may be prescribed^[14].

Treating Digestive Problems: For gastroparesis, medications such as metoclopramide or erythromycin may help, though they may become less effective over time^[14]. Eating smaller, more frequent meals can also ease symptoms^[10]. In some cases, electrical stimulation may be an option^[14].

Managing Bladder Issues: If you have a hypotonic (underactive) bladder, scheduled urination, assisted urination, or intermittent catheterization may be necessary^[14]. For an overactive bladder causing urgency and incontinence, bladder training exercises and Kegel exercises may help. If symptoms persist, medications called antimuscarinic agents or mirabegron may be effective^[14].

Treating Sexual Dysfunction: For erectile dysfunction caused by nerve damage, medications called phosphodiesterase-5 inhibitors or prostaglandin E₁ may help^[14]. These should only be prescribed after your cardiovascular health has been evaluated and the risk is considered low.

Managing Sweating Problems: If you have reduced sweating, you should avoid hot environments to prevent overheating^[10]. For excessive sweating, antiperspirants may provide relief^[2].

Lifestyle Measures: Regular physical activity can help reduce nerve pain, strengthen muscles, and improve overall health^[19][23]. Low-impact activities such as walking, swimming, or cycling are good choices. Getting sufficient sleep is also important for managing symptoms^[19]. If you are overweight, weight loss may help^[14].

Prevention Strategies

While it may not always be possible to prevent diabetic autonomic neuropathy entirely, you can take important steps to reduce your risk and minimize symptoms^[19].

Optimize Blood Sugar Control: The most important way to prevent or delay diabetic autonomic neuropathy is to keep your blood sugar levels within target ranges^[1][19]. Tight blood sugar control significantly reduces the risk of nerve damage. People with type 2 diabetes also benefit from addressing other cardiovascular risk factors^[1].

Regular Check-ups: If you have diabetes, you should have regular check-ups with your doctor to monitor your blood glucose control and look for any complications of diabetes^[5]. Early detection of nerve damage allows for prompt intervention.

Foot Care: Check your feet regularly to spot any signs of nerve damage or other complications^[19]. Wash and moisturize your feet, avoid going barefoot, and wear comfortable, well-fitting shoes.

Healthy Lifestyle: Maintain a healthy weight, exercise regularly, and avoid smoking^[5][19]. These measures help protect your nerves and overall health. Eating a healthy diet that supports blood sugar control is also essential.

Manage Other Health Conditions: Keep your blood pressure and cholesterol levels under control, as these factors also contribute to nerve damage^[21].