About the Author: Rohit Jayakar MD is a physician in the field of Physical Medicine & Rehabilitation at Jayakar Medical Group. He specializes in treating musculoskeletal injuries, neurological injuries, and chronic pain.
I recently saw a gentleman in his mid-sixties who had a 20 year history of poorly controlled diabetes. He came in because he noticed burning pain, numbness, and tingling in both his feet. Although this problem had started a year earlier, it was getting worse with time. His toes were beginning to claw, and he had a difficult time walking because he could not sense where his feet were in space. After performing a variety of blood and nerve tests, it was concluded that he had severe diabetic neuropathy.
Diabetic neuropathy can be an extremely disabling diagnosis with limited treatments and no cure. Still, there are steps anyone can take to prevent this condition. In this article, we’ll cover what neuropathy is, how it is related to diabetes, and what can be done to prevent it.
How Does Diabetes Lead to Nerve Damage?
Type II diabetes is a long-term disorder caused by inability to produce or respond to insulin appropriately, leading to large fluctuations in blood sugar. High blood sugar levels negatively affect many organ systems, including the nervous system.
Meanwhile, nerves stem from the spinal cord and project to the limbs to facilitate movement and provide feedback on limb position, temperature, touch, vibration, and pain sensations. Neuropathy signifies a problem with a nerve, which can affect motor function and sensation.
Diabetes is the leading cause of neuropathy in North America; approximately 50% of adults with diabetes will be affected by peripheral neuropathy, a neuropathy affecting nerves outside the brain and the spinal cord, in their lifetime.3 In these cases, high blood sugar levels begin to directly damage the nerves and weaken their surrounding small blood vessels, cutting off adequate blood supply and depriving the nerves of oxygen.
What are the Symptoms of Diabetic Neuropathy?
Diabetic peripheral neuropathy usually starts in the feet and can begin to affect the hands as the disease progresses. Common symptoms include numbness and tingling, burning pain, sensitivity to touch, and weakness.
Later on, there can also be damaging effects to autonomic nerves, which control organs like the heart, blood vessels, gastrointestinal tract, and urinary tract. Once these are affected, one can experience dizziness from orthostatic hypotension (a drop in blood pressure upon standing), bladder or bowel problems, and sexual dysfunction such as erectile dysfunction or vaginal dryness.
In the worst cases, diabetic neuropathy may call for an amputation. Due to the numbness resulting from nerve damage, people often do not realize when they have cuts on their feet, which can lead to ulcers and serious infections. Furthermore, people with diabetes also have weakened blood vessels, making wound healing more difficult. If the infection spreads to the bone, it often requires amputation.
Sometimes, the infections recur and can lead to subsequent surgeries and the loss of the entire lower leg––in fact, about 50% of patients who undergo surgery for a lower-limb amputation have diabetes.4 Unfortunately, 40%-80% of patients who undergo an amputation due to diabetes die within 5 years. These patients usually have advanced diabetes, so the cause of death ranges from infections and surgical complications to kidney and heart failure.4
How Can I Get Tested for Diabetic Neuropathy?
There is no definitive test for diabetic neuropathy, so it is first important to rule out other conditions that may be contributing to nerve damage. A complete neurological exam is required to assess motor function and sensation.
Additionally, blood tests are usually ordered to check blood sugar levels (hemoglobin A1c), thyroid hormone (TSH), vitamin levels (B12 and folate), and tests for certain infections or autoimmune conditions (such as HIV). A nerve test, called electromyography and nerve conduction studies (EMG/NCS for short), can also be done to further evaluate the location and extent of the nerve damage.
How Can I Reduce My Risk of Developing Diabetic Neuropathy?
Since elevated blood sugar leads to the nerve damage involved in diabetic neuropathy, the best way to help prevent this condition is by controlling the underlying diabetes.
Lifestyle Modifications
The ideal diet for those with type II diabetes includes foods rich in whole grains, fruits, vegetables, nuts, and legumes. Processed foods, red meat, and excessive carbohydrates should be avoided.5 The Mediterranean diet and the DASH diet (Dietary Approaches to Stop Hypertension) are both great options and have good evidence that they improve blood sugar control in diabetics.
Weight loss and exercise also can make a big difference in blood sugar levels. A minimum of 150 minutes of moderate physical activity (brisk walking) or 75 minutes of vigorous physical activity (running) should be done per week, in addition to 2 days a week of muscle strengthening. In diabetics, aerobic exercise should be prioritized (running, swimming, biking) in order to bring blood sugar levels down. For additional tips from the American Diabetes Association on how to safely start an exercise routine, click here.
Medication Management
Medications are frequently needed to better control blood sugar levels. While going into the doctor’s office for regular checkups and labs is certainly important, real change begins at home with proper medication adherence.
The most common medication used for type II diabetes is metformin, which is usually taken twice a day. There are several other classes of oral medications that are also taken at different times of day, including sulfonylureas, meglitinides, and thiazolidinediones.6 Click here for a more comprehensive list from the American Diabetes Association. For more advanced diabetes, insulin injections may also be needed one to four times a day.
Hygiene
Maintaining good foot hygiene is critical to reduce the likelihood of foot ulcers associated with diabetic neuropathy. A foot exam should be done by a healthcare provider at least once a year, and patients should check their feet daily for cuts or wounds. Feet should be kept moisturized to avoid cracks in the skin, and extra care should be taken while cutting toenails to avoid sharp edges. Moreover, closed toe shoes should be worn to protect the feet. While all this may sound like overkill, it can make a big difference in preventing foot ulcers and amputations!
Take the Proper Steps Today
Although there are medication options to help treat the pain resulting from nerve damage, there is currently no cure for diabetic neuropathy. Therefore, controlling the underlying diabetes is vital in reducing the likelihood of subsequent neuropathy. While diabetes can be notoriously difficult to control for some, changes made today can help prevent nerve damage and other complications from diabetes tomorrow.
When it comes to lifestyle modifications, emphasis should be placed on reducing processed carbohydrates and increasing exercise to reduce blood sugar levels. Several application based tools can be used to track daily carbohydrate and calorie intake, as well as workout routines. Wearable devices, such as continuous glucose monitors, can be used to track blood sugar and track workout intensity and calories burned. When medications are needed, a consistent regimen must be maintained to avoid spikes in blood sugar.
Lastly, the recent advent of virtual care makes it easier than ever to ensure close communication with your healthcare provider. If you have diabetes, try to regularly follow up with your healthcare provider for labs, skin checks, and to discuss any new symptoms. If you are experiencing numbness, tingling, or burning pain, make sure to mention this to your doctor so you can be evaluated appropriately.
All in all, a comprehensive approach to diabetes management can dramatically alter your life and help to prevent diabetic neuropathy altogether.
Rohit Jayakar, MD
References
- American Diabetes Association. Economic Costs of Diabetes in the U.S. in 2017. Diabetes Care. 2018 May;41(5):917-928. doi: 10.2337/dci18-0007. Epub 2018 Mar 22. PMID: 29567642; PMCID: PMC5911784.
- Khan MAB, Hashim MJ, King JK, Govender RD, Mustafa H, Al Kaabi J. Epidemiology of Type 2 Diabetes – Global Burden of Disease and Forecasted Trends. J Epidemiol Glob Health. 2020 Mar;10(1):107-111. doi: 10.2991/jegh.k.191028.001. PMID: 32175717; PMCID: PMC7310804.
- Hicks CW, Selvin E. Epidemiology of Peripheral Neuropathy and Lower Extremity Disease in Diabetes. Curr Diab Rep. 2019;19(10):86. Published 2019 Aug 27. doi:10.1007/s11892-019-1212-8
- Moulik PK, Mtonga R, Gill GV. Amputation and mortality in new-onset diabetic foot ulcers stratified by etiology. Diabetes Care. 2003 Feb;26(2):491-4. doi: 10.2337/diacare.26.2.491. PMID: 12547887.
- Ley SH, Hamdy O, Mohan V, Hu FB. Prevention and management of type 2 diabetes: dietary components and nutritional strategies. Lancet. 2014;383(9933):1999-2007. doi:10.1016/S0140-6736(14)60613-9.
- Feingold KR. Oral and Injectable (Non-Insulin) Pharmacological Agents for Type 2 Diabetes. 2020 Jul 12. In: Feingold KR, Anawalt B, Boyce A, Chrousos G, de Herder WW, Dhatariya K, Dungan K, Grossman A, Hershman JM, Hofland J, Kalra S, Kaltsas G, Koch C, Kopp P, Korbonits M, Kovacs CS, Kuohung W, Laferrère B, McGee EA, McLachlan R, Morley JE, New M, Purnell J, Sahay R, Singer F, Stratakis CA, Trence DL, Wilson DP, editors. Endotext [Internet]. South Dartmouth (MA): MDText.com, Inc.; 2000–. PMID: 25905364.
- Egede LE, Gebregziabher M, Dismuke CE, Lynch CP, Axon RN, Zhao Y, Mauldin PD. Medication nonadherence in diabetes: longitudinal effects on costs and potential cost savings from improvement. Diabetes Care. 2012 Dec;35(12):2533-9. doi: 10.2337/dc12-0572. Epub 2012 Aug 21. PMID: 22912429; PMCID: PMC3507586.
- Lau DT, Nau DP. Oral antihyperglycemic medication nonadherence and subsequent hospitalization among individuals with type 2 diabetes. Diabetes Care. 2004 Sep;27(9):2149-53. doi: 10.2337/diacare.27.9.2149. PMID: 15333476.