Treatment-induced neuropathy of diabetes (TIND), also called insulin neuritis, may be more common than previously thought, according to a review published in the October issue of Current Diabetes Reports.1 Past research has suggested that TIND has an incidence of about 1%, but the review cites more recent research that indicates that up to 10.9% of study participants may meet the criteria for the condition. In the largest retrospective review to date, researchers found that 104 of 954 individuals evaluated from 2008 to 2012 at a tertiary care diabetic neuropathy clinic met criteria for TIND.2
TIND is a painful acute neuropathy that affects autonomic and small somatosensory nerve fibers, causing autonomic symptoms such as orthostatic hypotension or syncope along with burning or shooting pain that typically affects the extremities but may be more generalized. Patients may also experience worsening of microvascular disease, including retinopathy and nephropathy. The condition can affect people with type 1 diabetes mellitus (T1D) or type 2 diabetes mellitus (T2D) who have had a prolonged period of hyperglycemia. It usually begins 4 to 6 weeks after rapid normalization of glucose levels when initiating intensive glycemic control with insulin, oral agents, or (rarely) extreme diet control. In fact, the Gibbons and Freeman2 study found that development of TIND was tied to how rapidly HbA1c dropped: a decrease of 2% to 3% over 3 months was linked to 20% absolute risk for TIND, while a decrease of more than 4% was linked to over 80% increased absolute risk.
Pain in TIND is usually more severe and more refractory to therapy than that of polyneuropathy of diabetes. Moreover, the autonomic symptoms of TIND are more prevalent and more severe. TIND also develops more rapidly, while symptoms of diabetic polyneuropathy are more insidious and may develop over years.
While TIND is usually self-limiting—symptoms gradually improve within weeks to months—the condition is usually extremely painful and often treatment-resistant. One case series found that participants rated the pain as 10 on a scale of 1 to 10, despite combined treatment with 2 to 3 analgesics.3 However, some patients may experience longer-term symptoms, especially those with poorly controlled diabetes. A recent study of 26 individuals with T1D found that about 27% with unstable glycemic control continued to have worsened neuropathy and microvascular complications 7 to 8 years after experiencing TIND.4
1. Gibbons CH. Treatment-induced neuropathy of diabetes. Curr Diab Rep. 2017;17:127.
2. Gibbons CH, Freeman R. Treatment-induced neuropathy of diabetes: an acute, iatrogenic complication of diabetes. Brain. 2015;138:43-52.
3. Gibbons CH, Freeman R. Treatment-induced diabetic neuropathy: a reversible painful autonomic neuropathy. Ann Neurol. 2010;67:534-541.
4. Gibbons CH. Treatment induced neuropathy of diabetes-Long term implications in type 1 diabetes. J Diabetes Complications. 2017;31:715-720.