Unexplained Tingling and Numbing on Your Feet Might Be Due to Small Fiber Neuropathy; What Is This?

According to a recent study the number of people that have been experiencing unexplained tingling, numbing, and sometimes burning in their feet has steadily been increasing over the last 20 years. The authors of the study suggest that these mysterious sensations are due to small fiber neuropathy.

What is Small Fiber Neuropathy?

(Photo: ROMAN ODINTSOV from Pexels)

Small fiber sensory neuropathy, according to Johns Hopkins Medicine, is a disorder where the only affected areas are small sensory cutaneous nerves. A majority of those who are diagnosed with small fiber neuropathy first experience sensory disturbances in their feet that slowly but surely move their way upwards.

Often this is due to impaired glucose metabolism or diabetes and may soon progress to typical diabetic polyneuropathy. Symptoms are primarily sensory in nature which includes unusual sensations like pins-and-needles, tingling, numbness, pricks, and even burning.

Since small fiber neuropathy does not involve large sensory fibers which convey balance information to the brain, nor does it involve motor nerve fibers tasked with controlling muscles, patients don't have balance issues or muscle weakness.

ALSO READ: Non-Invasive Novel Light Technique Accurately Measures Cranial Blood Flow for Better Diagnosis

Understanding the Source of Unexplained Tingling and Numbness in the Feet

In a study published in the journal Neurology, titled "Small Fiber Neuropathy Incidence, Prevalence, Longitudinal Impairments, and Disability" researchers analyzed records of patients diagnosed with small fiber neuropathy in Minnesota and adjacent counties in a 20-year period. Data collected from 94 people were then compared with 282 people of the same age and sex that weren't diagnosed with neuropathy. Participants were followed and monitored over a six-year period.

According to the study, small fiber neuropathy appears to occur in 13.3 per 100,000 people with the rate of occurrence increasing steadily during the duration of the study.

Author of the study Christopher Klein from Mayo Clinic, Rochester, and a Fellow of the American Academy of Neurology explains that the increase could be because, in part, of greater awareness of the condition. He adds that another possible reason behind the increasing levels of small fiber neuropathy could be the rate of overweight and obesity in the area that is in a much higher risk factor for the condition. A higher body mass index is a risk factor not only for diabetes but also for high triglycerides that may lead to neuropathy reports NeuroScienceNews.

Participants of the study that were diagnosed with small fiber neuropathy had an average BMI of 30.4 while those that did not have neuropathy had an average BMI of 28.5. Additionally. A BMI of 18.5 to 24.9 is classified as healthy while 25-29.9 is overweight and 30.0 BMI and higher are considered obese.

The study finds that 50% of participants with neuropathy were also diagnosed with diabetes, compared to 22% that were not. Those with small fiber neuropathy were also seen to more likely experience insomnia and were more likely to suffer from heart attacks.

Klein explains that although it's good news that most of the patients diagnosed with idiopathic neuropathy had no major impairments or disabilities however it does increase risks of other adverse health conditions.