Painful diabetic peripheral neuropathy (DPN) arises from damage to sensory neurons, manifesting in persistent pain. Progressive nerve degeneration can result in sensory loss and, in severe cases, amputation, exacerbating emotional distress and diminishing quality of life. Continuing investigation into DPN mechanisms is essential for advancing effective pain management. Our previous narrative review identified oxidative stress and central sensitization as key pathways linking hyperglycemia to nerve injury and pain. The present review provides an updated synthesis of evidence in this area. The original PubMed search term was expanded to include metabolic syndrome and pain modulation, and studies published between September 2021 and February 2026 were examined. The current findings reinforce earlier conclusions that alterations within the central nervous system and central sensitization are prominent features of painful DPN. Emerging evidence suggests that metabolic syndrome such as overweight may impair pain modulation in individuals with or without risk of diabetes. Future research should determine whether impaired pain modulation can serve as an early indicator of DPN, enabling earlier intervention. Clarifying these mechanisms may also help explain why medications that restore pain modulation show therapeutic promise for this complex chronic pain condition.
Ye et al. (Wed,) studied this question.