From the Guidelines
Treatment-induced neuropathy in Diabetes Mellitus (DM) is a condition where rapid reduction in blood glucose levels, particularly a drop in HbA1c >3% in a short period, can cause a paradoxical flare-up of microvascular complications, including neuropathy. This can occur when glycaemic control is managed too aggressively, especially in patients with advanced DM [ 1 ].
Key Factors
- Rapid reduction in HbA1c: A drop of >3% in a short period can trigger treatment-induced neuropathy [ 1 ]
- Prior poor glycemic control: Patients with a history of high glycaemia are more susceptible to this condition [ 1 ]
- Microvascular complications: Presence of conditions like retinopathy, nephropathy, or neuropathy can increase the risk of treatment-induced neuropathy [ 1 ]
Management
- Gradual lowering of blood glucose levels: Over several weeks to minimize the risk of treatment-induced neuropathy [ 1 ]
- Careful monitoring: Strict monitoring of glycaemic control is essential in patients with advanced DM [ 1 ]
- Medication selection: Consideration of newer drugs like SGLT-2 inhibitors or GLP1-receptor agonists, which may have a different effect on glycaemia compared to older medications [ 1 ]
From the Research
Definition and Prevalence of Treatment-Induced Neuropathy in Diabetes Mellitus (DM)
- Treatment-induced neuropathy in diabetes, also referred to as insulin neuritis, is a rare iatrogenic small fibre neuropathy caused by an abrupt improvement in glycaemic control in the setting of chronic hyperglycaemia 2.
- The prevalence of treatment-induced neuropathy in diabetes is not well-known, but it is estimated to occur in up to 10% of patients with diabetic neuropathy 2, 3, 4.
Risk Factors and Pathophysiology
- The risk of developing treatment-induced neuropathy in diabetes is increased with a rapid decline in blood glucose levels, particularly with a decrease in glycosylated haemoglobin A1C (HbA1c) of ≥2% points over 3 months 2, 3.
- A decrease in HbA1c of 2-3% points over 3 months is associated with a 20% absolute risk of developing treatment-induced neuropathy in diabetes, while a decrease of >4% points over 3 months is associated with an absolute risk exceeding 80% 2.
- The pathophysiology of treatment-induced neuropathy in diabetes is not fully understood, but it is thought to be related to the rapid change in glucose control, which can lead to peripheral nerve degeneration and autonomic dysfunction 5.
Clinical Manifestations and Diagnosis
- Treatment-induced neuropathy in diabetes is characterized by the acute onset of neuropathic pain and/or autonomic dysfunction within 8 weeks of a large improvement in glycaemic control 2.
- The clinical manifestations of treatment-induced neuropathy in diabetes include neuropathic pain, autonomic dysfunction, retinopathy, and nephropathy 2, 4.
- A standard workup for the diagnosis of treatment-induced neuropathy in diabetes includes detailed structured neurologic examinations, glucose control logs, pain scores, autonomic symptoms, and other microvascular complications 6.
Treatment and Prevention
- Supportive care is currently the only recommended treatment for treatment-induced neuropathy in diabetes 4.
- Slower changes to glucose control are suggested to prevent the development of treatment-induced neuropathy in diabetes, although there is no prospective data to support this recommendation 3.
- Future research is necessary to define the underlying mechanism, prevent development, and guide treatment recommendations for treatment-induced neuropathy in diabetes 6, 3, 4.