Distal Symmetric Polyneuropathy

Abstract

Importance Peripheral neuropathy is a highly prevalent and morbid condition affecting 2–7% of the population. Patients frequently suffer from pain and are at risk of falls, ulcerations, and amputations. We aimed to review recent diagnostic and therapeutic advances in peripheral neuropathy in distal symmetric polyneuropathy, the most common subtype of peripheral neuropathy. Observations and Advances Current evidence supports limited routine laboratory testing in patients with distal symmetric polyneuropathy. Patients without a known cause should have a complete blood count, comprehensive metabolic panel, B12, serum protein electrophoresis with immunofixation, fasting glucose, and a glucose tolerance test. The presence of atypical features such as asymmetry, non-length-dependence, motor predominance, acute or subacute onset, and/or prominent autonomic involvement should prompt a consultation with a neurologist or neuromuscular specialist. Electrodiagnostic tests and magnetic resonance imaging of the neuroaxis are the main drivers of the cost of the diagnostic evaluation, but evidence supporting their use is lacking. Strong evidence supports the use of tricyclic antidepressants, serotonin and norepinephrine reuptake inhibitors, and voltage-gated calcium channel ligands in the treatment of neuropathic pain. More intensive glucose control substantially reduces the incidence of distal symmetric polyneuropathy in patients with type 1 diabetes, but does not in type 2 diabetes. Conclusions and Relevance The opportunity exists to improve guideline concordant testing in distal symmetric polyneuropathy patients. Moreover, the role of electrodiagnostic tests needs to be further defined, and interventions to reduce magnetic resonance imaging use in this population are needed. Even though several efficacious medications exist for neuropathic pain treatment, pain is still under-recognized and undertreated. New disease modifying medications are needed to prevent and treat peripheral neuropathy, particularly in type 2 diabetes.

Diabetes and obesity are the main metabolic drivers of peripheral neuropathy

“…This disease affects patients by causing pain, decreased quality of life, falls, ulcerations, and amputations 3, 4, 5. Unfortunately, outside of medications for neuropathic pain, few therapies exist to help patients with peripheral neuropathy 4.…”

Management of peripheral neuropathy symptoms with a fixed dose combination of high-dose vitamin B1, B6 and B12: A 12-week prospective non-interventional study in Indonesia

“…[17][18][19] Vitamin B (B 1 , B 6 , B 12 ) deficiencies, may lead to an impaired nervous system. 20 The three vitamins are complementary as they act via different modes of action. 19 Thiamine diphosphate is the active form of vitamin B 1 and serves as a cofactor for several enzymes involved primarily in carbohydrate catabolism 21 and may prevent microvascular complications in diabetes.…”

Dynamic Properties of Skeletal Muscle Contraction in Rats with Diabetes

“…Diabetic neuropathy correlates with a high risk of cardiovascular complications [3,4]. Patients with diabetic polyneuropathy are also at risk for the formation of trophic ulcers that do not heal for a long time and often lead to amputating a limb [5][6][7]. In the USA, 15% of all patients with diabetes will develop foot ulcers [8].…”