Neuropathic Pain With and Without Diabetic Peripheral Neuropathy in Type 1 Diabetes

Diabetic peripheral neuropathy (DPN) is common; however, the features and burden of neuropathic pain (NP) in type 1 diabetes (T1D) are poorly understood. We evaluated the incidence of first occurrence, annual prevalence, remission, and risk factors for NP during long-term follow-up of participants with T1D.

The Michigan Neuropathy Screening Instrument (MNSI) was administered annually (1994-2020) for 1,324 participants in the Epidemiology of Diabetes Interventions and Complications (EDIC) study. NP with clinical signs of DPN (NP DPN+) was defined according to self-reported NP plus an examination score >2, while NP without clinical signs of DPN (NP DPN-) was defined according to self-reported NP and an examination score ≤2.

At EDIC year 1, median age for participants was 36 years (interquartile range 30, 41), diabetes duration 13 years (10, 18), and HbA1c 7.9% (7.2, 8.9). At year 26 (median diabetes duration 39 years), cumulative incidence of NP was 57%, regardless of concomitant clinical signs of DPN (36% NP DPN+ vs. 46% NP DPN-). NP prevalence was 20% at 26 years (11% NP DPN+ and 9% NP DPN-), suggesting frequent remission. Annualized remission rates were similar regardless of pain medication use. In addition to HbA1c, female sex was associated with NP DPN-.

NP incidence in T1D was high and frequently occurred in the absence of clinical signs of neuropathy, as assessed with the MNSI. Pain remission was not explained by pain medication use. Effective clinical strategies for identification and management are needed.