Essential Points:

• Diabetes complications significantly impact balance and fall risk: Long-term effects such as nerve damage, vision loss, and hearing/vestibular dysfunction can increase the likelihood of falling due to impaired sensory input and motor control.

• Nerve damage from diabetes affects balance: Conditions like peripheral neuropathy and autonomic neuropathy lead to numbness, pain, and weakness, making it difficult to maintain balance and increasing fall risk.

• Vision and hearing loss further exacerbate fall risk: Diabetic eye diseases, including diabetic retinopathy and cataracts, disrupt vision, while hearing loss and vestibular dysfunction compromise spatial awareness, both contributing to instability and falls.

This article is the second in a series of three discussing all things diabetes. If you haven’t had a chance to read the first article make sure to check it out here: What is Diabetes?

In this article we will be discussing what happens after someone is considered diabetic, and the long term complications that can arise with this disease. Although complications are many and varied when it comes to diabetes, we will hone in on the ones that are more likely to affect both your balance and your risk of falling.

Common Complications from Diabetes

Diabetes is a disease of excessive blood sugar (hyperglycemia) and an inability to use it appropriately in the body. Although this may seem like a small problem, excessive blood sugar can wreak havoc on your body. Some of the most common secondary complications from diabetes include (1):

• Heart Disease

• Nerve Damage

• Vision Loss

• Oral Damage

• Kidney Damage

• Hearing Loss and Vestibular Dysfunction

When it comes to deteriorating balance and increased fall risk in those with diabetes, the true villians are nerve damage, vision loss, and hearing loss/vestibular dysfunction.

Nerve Damage

When nerves are damaged secondary to diabetes it is termed diabetic neuropathy. Diabetic neuropathy occurs when blood vessels surrounding a nerve are damaged leading to malnourishing of the nerves. It can lead to numbness, pain, odd sensations around your body, or an inability to use your muscles efficiently.

Nerve damage can severely limit the ability to live life independently and on your own terms. Both a dulling of sensation and reduced muscular control significantly increase the risk of falling and should be mitigated as much as possible.

There are 4 types of nerve damage that can occur with diabetes that can affect balance (2). These include:

• Peripheral Neuropathy (Peripheral Diabetic Neuropathy)

• Proximal Neuropathy (Diabetic Amyotrophy)

• Focal Neuropathy (Diabetic Mononeuropathy)

• Autonomic Neuropathy

Peripheral Neuropathy (Peripheral Diabetic Neuropathy)

Peripheral nerve damage is the most common form of diabetic neuropathy a person with diabetes will experience. It’s estimated that 50% of those with diabetes will develop this type of nerve damage over the course of their life. (3) Peripheral diabetic neuropathy (PDN) often manifests with symptoms in both feet but can also affect the arms, hands, and legs. (2) “Peripheral” is an anatomic term meaning away from the center and thus means nerve symptoms manifest away from the trunk of the body.

Symptoms include numbness, tingling, burning, and generalized pain. These symptoms can negatively affect a person’s ability to walk safely due to the altered sensations they are receiving from the ground (click here to learn more about how sensation affects our balance). Additionally, due to this altered sensation, those with PDN may not feel when they have a foot injury. Cuts, scrapes, and blisters are common but often go unnoticed with PDN if daily foot checks are not performed. A foot injury which is not taken care of can spiral out of control and result in infected wounds, foot ulcers, and potentially amputation. (4)

Proximal Neuropathy (Diabetic Amyotrophy)

Proximal nerve damage is similar to PDN but occurs near or on the trunk of the body. It usually affects the upper legs, gluteal region (buttocks), hips, thighs, and stomach. (2) This form of of neuropathy is very rare in those with diabetes and accounts for roughly 1% of cases for those with type 2 diabetes. (5) Those at risk are usually older men and it is not uncommon for those with well-controlled diabetes, or recently diagnosed, individuals to have this type of neuropathy. (5)

Nerve pain will often start in the upper thigh of only one leg then spread to surrounding regions usually only affecting one side of the body. (5) Symptoms include pain, generalized leg weakness, loss of reflex integrity, muscle wasting (atrophy), and weight loss. (6) Symptoms may progressively worsen over a span of several months or years before leveling off and easing. After this easing of symptoms recurrence is possible. (5-6)

Focal Neuropathy (Diabetic Mononeuropathy)

Focal nerve damage, or diabetic mononeuropathy, is nerve damage that only affects one singular nerve. (7) This form of neuropathy often comes on suddenly in older patients with diabetes. Symptoms are dictated by which nerve is affected and to what extent damage has been done. Almost any nerve in the body is susceptible to focal neuropathy leading to a variety of presentations from altered sensation, weakness, vision loss, or general imbalances. Symptoms often disappear or lessen weeks to months after the initial onset.

A common cause of focal neuropathy is entrapment. (8) Entrapment of a nerve occurs when a nerve is compressed between bodily tissues such as bone and muscle. A well known example of entrapment is carpal tunnel syndrome wherein nerves of the wrist become compressed and lead to numbing and weakness of the hand. Those with diabetes are more susceptible to nerve entrapment type injury due to physiological and structural changes of the nerves as well as the surrounding tissues. (9)

Autonomic Neuropathy

Autonomic neuropathy refers to damage of the nerves that supply your internal organs. (10) Due to the intricate and extensive functions of our internal organs this type of nerve damage can have a variety of effects. Included in these possible effects are a disruption in vision as well as dulled sense of hypoglycemia (low blood glucose) also known as hypoglycemia unawareness.

Hypoglycemia unawareness essentially means that a person is unable to notice the signs of low blood glucose and thus do not treat it appropriately. It may result in extreme low blood glucose events such as passing out.

Vision Loss (Diabetic Eye Disease)

Visual loss in those with diabetes is common in later stages of the disease, but initial damage can start as early as prediabetes. (11) In all cases, damage to the visual system starts with sustained hyperglycemia damaging blood vessels in the area of the eyes. Such damage may lead to malnourishment of surrounding tissues or excessive fluid leakage. (12)

Initially, in the prediabetes stage, visual disruption may come in the form of blurred vision. (11) Blurry vision may be caused by a change in fluid levels or swelling in eye tissues. Although blurred vision is concerning, at these earlier stages it is reversible if glucose levels are decreased. If chronic hyperglycemia is not corrected, and the diabetes progresses, vision loss will progress as well. Complete blindness is a possibility later on in the disease process.

Vision, as discussed in the article The Three Bodily Balance Systems, is a large part of balance. When vision is disrupted we no longer have a visual reference for our body’s position in space. Such a loss in spatial orientation may result in losses of balance leading to falls.

Advanced forms of diabetic eye disease include:

• Diabetic Retinopathy

• Diabetic Macular Edema (DME)

• Neovascular Glaucoma

• Cataracts

Diabetic Retinopathy

Diabetic retinopathy occurs when the retina (the light-sensitive portion near the back of the eye) is damaged. (13) One-third of diabetics over the age of 40 years old have signs of diabetic retinopathy. (14) This form of eye damage may occur in those with type 1 and type 2 diabetes. The early stages consist of blood vessels weakening, bulging, and leaking fluid into the retina. This period of damage is termed non-proliferative diabetic retinopathy (NPDR), or in other words damage is occurring and new blood vessels are not proliferating (not growing). (15)

The advanced stage of diabetic retinopathy is termed proliferative diabetic retinopathy. (15) In this stage the body attempts to correct for damaged blood vessels by proliferating (growing) new ones. Unfortunately, these vessels can be extremely fragile. These new vessels are prone to breaking and leaking into the gelly-like fluid (vitreous) of the eye. Eventually, retinal detachment and nerve damage may occur due to swelling and scar tissue formation.

General symptoms include:

• Blurred vision

• “Empty” vision

• Strings or dark spots known as “floaters”

• Fluctuating vision (changing in focus)

• Complete vision loss.

Diabetic Macular Edema (DME)

Diabetic Macular Edema (DME) is a secondary complication that arises in diabetic retinopathy. (16) The macula is a small ~5mm area that lies in the back of the retina. It is responsible for central vision, color vision, and fine detail. (17) As fluid leaks into the vicinity of the retina, the macula may swell and result in warped vision. Along with warping, vision may deteriorate significantly. Approximately 1 in every 15 individuals with diabetes will develop DME. (18)

General symptoms include:

• Blurred vision

• Double vision

• Increase in number of eye floaters

• Wavy vision

• Dull /faded color vision

Neovascular Glaucoma

Neovascular glaucoma is an abnormal increasing of pressure in the eye which leads to damage to the optic nerve. (19) The optic nerve exits the back of the eye and is responsible for relaying visual information to the brain for interpretation. In diabetes, the abnormal blood vessel growth associated with diabetic retinopathy may lead to a malfunctioning of the eye drainage system. (16) This malfunctioning leads to fluid being unable to escape and thus a building of pressure occurs. The pressure leads to pinching of the optic nerve leading to eventual permanent damage and loss of eyesight.

The majority of people with glaucoma are unaware of the disease until their eyesight starts to diminish. (20) Due to there being no noticeable symptoms initially, glaucoma is the leading cause of irreversible blindness.

General symptoms include:

• Blind spots in vision

• Diminished peripheral vision (narrowing vision)

• Blurry vision

• Halo effect around lights

• Complete blindness

Cataracts

Cataracts are a clouding of the eye lense due to clumping of proteins over time. (21-22) Cataracts are quite common in the elderly with more than half of those 80 years and older having a history of them. Cataracts may occur earlier in younger populations with diabetes due to the disruption in blood supply and thus disruption of the normal protein turnover in the lenses. 32.2% of diabetic adults over the age of 45 have been diagnosed with cataracts to some degree. (23) Those who have had a diagnosis of diabetes for over 10 years are roughly 8% more likely to have cataracts than those diagnosed for less than 10 years. (23)

General symptoms include:

• Fading color vision

• Cloudy or blurry vision

• Double vision

• Seeing halos around lights

• Sensitivity to light and glares

• Diminished vision at nighttime

Hearing Loss and Vestibular Dysfunction

Hearing loss itself is not directly linked to an increase in balance deficits. But, due to the anatomy of the ear (discussed more here), when hearing losses occur the chance of vestibular dysfunction is also present. Hearing loss is two times as prevalent and vestibular dysfunction is 70% more likely in those with diabetes. (24, 25) The structure which houses both the hearing and vestibular organs is termed the bony labyrinth. Inside of this bony structure is housed the cochlea (hearing structure), the semi-circular canals (balance/vestibular structures), and the vestibule (connects the two sections and houses two more balance related structures called the saccule and utricle). (26)

As in prior sections, the proposed cause of hearing and vestibular damage is a disruption in the blood vessels around ear structures leading to a cascade of negative changes and damage in the surrounding tissues. (27) These structures may include the vestibulocochlear nerve, cochlea, as well as vestibular related organs. It is this damage that may affect both the hearing and vestibular systems in a person with diabetes and create potential balance deficits.

General symptoms of diabetic hearing loss:

• Ringing in ears

• Difficulty understanding others in conversation

• Needing to increase volume excessively on phone or TV to hear

• Difficulty understanding others, especially when not looking at them directly

General symptoms of diabetic vestibular dysfunction:

• Increased feeling of unsteadiness on feet

• Feeling of dizziness or that the room is spinning

• Blurred vision, especially when turning head

• Feeling of nausea when changing positions

• Bouncing vision (oscillopsia)

Wrap-Up

As noted in the Three Bodily Balance Systems article, the body uses the visual system, somatosensory system, and the vestibular system to maintain balance. When all three systems are intact the risk of falls is drastically reduced. Unfortunately, all three of these systems can be affected when diabetes is present. Although the body can compensate fairly well when one system is not functioning properly, problems start to emerge when two or more systems are disrupted. Researchers found that when neuropathy or retinopathy were present, vestibular dysfunction prevalence increased to 76% and 71% respectively. (25) Consequently the chances of at least two balance systems being disrupted in those with diabetes is significant.

Due to the significant risk of balance disorders in those with diabetes, secondary disease complications should be prevented when possible or dealt with immediately. In the third and final article of this series, 4 Ways to Manage Diabetes Complications for Reduced Fall Risk, we will dive into the preventative, restorative, and adaptive aspects of diabetes treatment.

References

1) Prevent diabetes complications. Centers for Disease Control and Prevention. https://www.cdc.gov/diabetes/managing/problems.html. Published November 3, 2022. Accessed December 4, 2022.

2) Diabetes and nerve damage. Centers for Disease Control and Prevention. https://www.cdc.gov/diabetes/library/features/diabetes-nerve-damage.html. Published June 20, 2022. Accessed December 4, 2022.

3) Hicks CW, Selvin E. Epidemiology of peripheral neuropathy and lower extremity disease in diabetes. Current diabetes reports. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6755905/. Published August 27, 2019. Accessed December 4, 2022.

4) Nerve damage & amputation. DiabetesCanadaWebsite. https://www.diabetes.ca/managing-my-diabetes/preventing-complications/nerve-damage---amputation#:~:text=Diabetic%20peripheral%20neuropathy%20increases%20the,or%20blisters%20in%20these%20areas. Accessed December 4, 2022.

5) Diabetic neuropathy. Diabetic Neuropathy | Johns Hopkins Medicine. https://www.hopkinsmedicine.org/health/conditions-and-diseases/diabetes/diabetic-neuropathy-nerve-problems. Published August 18, 2020. Accessed December 4, 2022.

6) Proximal neuropathy. National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/diabetes/overview/preventing-problems/nerve-damage-diabetic-neuropathies/proximal-neuropathy. Accessed December 4, 2022.

7) Early treatment can prevent further complications. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/diabetic-neuropathy/in-depth/diabetic-neuropathy-types/art-20094456. Published May 13, 2022. Accessed December 4, 2022.

8) Focal neuropathies. National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/diabetes/overview/preventing-problems/nerve-damage-diabetic-neuropathies/focal-neuropathies. Accessed December 4, 2022.

9) N; REM. Entrapment neuropathies in diabetes mellitus. World journal of diabetes. https://pubmed.ncbi.nlm.nih.gov/27660694/. Accessed December 4, 2022.

10) Autonomic neuropathy. National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/diabetes/overview/preventing-problems/nerve-damage-diabetic-neuropathies/autonomic-neuropathy. Accessed December 4, 2022.

11) Diabetic eye disease. National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/diabetes/overview/preventing-problems/diabetic-eye-disease. Accessed December 4, 2022.

12) Diabetes and Vision Loss. Centers for Disease Control and Prevention. https://www.cdc.gov/diabetes/managing/diabetes-vision-loss.html#:~:text=Diabetic%20retinopathy%20is%20caused%20when,vision%20or%20stopping%20blood%20flow. Published May 7, 2021. Accessed December 4, 2022.

13) Diabetic retinopathy. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/diabetic-retinopathy/symptoms-causes/syc-20371611. Published June 24, 2021. Accessed December 4, 2022.

14) National Diabetes Statistics Report, 2014 - centers for disease control ... https://stacks.cdc.gov/view/cdc/23442/cdc_23442_DS1.pdf. Accessed December 4, 2022.

15) Diabetic retinopathy. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/diabetic-retinopathy/symptoms-causes/syc-20371611#:~:text=In%20this%20more%20common%20form,and%20blood%20into%20the%20retina. Published June 24, 2021. Accessed December 4, 2022.

16) Diabetic retinopathy. National Eye Institute. https://www.nei.nih.gov/learn-about-eye-health/eye-conditions-and-diseases/diabetic-retinopathy#:~:text=Diabetic%20retinopathy%20can%20cause%20abnormal,cause%20vision%20loss%20and%20blindness). Accessed December 4, 2022.

17) What is the macula? Macular Society. https://www.macularsociety.org/macular-disease/macula/. Accessed December 4, 2022.

18) Diabetes and Vision Loss. Centers for Disease Control and Prevention. https://www.cdc.gov/diabetes/managing/diabetes-vision-loss.html. Published May 7, 2021. Accessed December 4, 2022.

19) What is glaucoma? glaucoma.org. https://glaucoma.org/learn-about-glaucoma/what-is-glaucoma/. Published August 4, 2022. Accessed December 4, 2022.

20) Glaucoma. Glaucoma | Johns Hopkins Medicine. https://www.hopkinsmedicine.org/health/conditions-and-diseases/glaucoma. Accessed December 4, 2022.

21) Curious about cataracts? Curious About Cataracts? | ADA. https://diabetes.org/diabetes/eye-health/take-charge/curious-about-cataracts#:~:text=What%20Causes%20Cataracts,accelerate%20the%20development%20of%20cataracts. Accessed December 4, 2022.

22) Cataracts. National Eye Institute. https://www.nei.nih.gov/learn-about-eye-health/eye-conditions-and-diseases/cataracts#:~:text=Most%20cataracts%20are%20caused%20by,your%20lens%20%E2%80%94%20or%20a%20cataract. Accessed December 4, 2022.

23) Products - data briefs - number 344 - July 2019. Centers for Disease Control and Prevention. https://www.cdc.gov/nchs/products/databriefs/db344.htm. Published July 18, 2019. Accessed December 4, 2022.

24) Hearing loss is common in people with diabetes. National Institutes of Health. https://www.nih.gov/news-events/news-releases/hearing-loss-common-people-diabetes. Published September 20, 2015. Accessed December 4, 2022.

25) Agrawal Y;Carey JP;Della Santina CC;Schubert MC;Minor LB; Diabetes, vestibular dysfunction, and falls: Analyses from the National Health and Nutrition Examination Survey. Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology. https://pubmed.ncbi.nlm.nih.gov/20856157/. Accessed December 4, 2022.

26) Benjamin Wedro MD. The antatomy of hearing and balance. MedicineNet. https://www.medicinenet.com/ear_anatomy_of_hearing_and_balance/views.htm. Published June 13, 2018. Accessed December 4, 2022.

27) Diabetes and hearing loss. Diabetes and Hearing Loss | ADA. https://diabetes.org/diabetes/diabetes-and-hearing-loss. Accessed December 4, 2022.

Thank you for reading the article! I hope you learned a few new things about diabetic complications and how they can be a detriment to balance and safety. Be sure to leave a comment below if you have any questions or insight on the article.

Happy falling!