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

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

Research Design and Methods: The Michigan Neuropathy Screening Instrument was administered annually (1994-2020) in 1,324 participants in the Epidemiology of Diabetes Interventions and Complications (EDIC) study. Neuropathic pain (NP) with clinical signs of DPN (NP DPN+) was defined by self-reported neuropathic pain plus an examination score >2, while neuropathic pain without clinical signs of DPN (NP DPN-) was defined by self-reported neuropathic pain and an examination score ≤2.

Results: At EDIC year 1, participants had median [IQR] age 36 [30, 41] years, diabetes duration 13 [10, 18] years, and HbA1c 7.9 [7.2, 8.9]%. At year 26 (median diabetes duration 39 years), cumulative incidence of neuropathic pain was 57%, regardless of concomitant clinical signs of DPN (36% NP DPN+ vs. 46% NP DPN-). Neuropathic pain prevalence was 20% at 26 years (11% NP DPN+; 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-.

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