Investigating dermal hypervascularity in painful diabetic neuropathy

Diabetic Peripheral Neuropathy (DPN) affects up to half of people with diabetes and can be either painless or painful. Painful-DPN causes distressing sensations like burning, electric shocks, cold pain, and tingling, particularly in the feet and legs. These sensations can be severe and hard to treat. Current treatments only reduce the pain slightly and often come with side effects. This is partly because we don’t fully understand why some people with DPN experience pain while others don’t. One way to study Painful-DPN is by taking small skin biopsy samples from the leg to examine the pain-sensing nerves and surrounding blood vessels. We think these blood vessels release substances that make the nerves more sensitive, increasing pain signals. However, more research is needed to understand why people with Painful-DPN have more blood vessels in their skin and how this relates to their pain. This study aims to explore why people with Painful-DPN have more blood vessels in their skin and whether this contributes to their pain. We will recruit 80 participants, divided into four groups of 20: Painful-DPN, Painless-DPN, people with diabetes but no DPN, and people without diabetes or nerve damage. All participants will undergo detailed nerve function tests and have two small skin biopsies (3mm) taken from the thigh under local anaesthetic. No stitches are needed for the biopsy, and only a simple dressing will be applied afterward.