Contemporary Prevalence of Diabetic Neuropathy in Type 1 Diabetes (T1D)—Findings from the T1D Exchange

Abstract

Diabetic peripheral neuropathy (DPN) is a major cause of disability, mortality and poor quality of life in patients with T1D, with prior reported prevalence rates of up to 35%. The contemporary prevalence of DPN in T1D patients was evaluated in T1D Exchange Registry centers throughout the United States. The Michigan Neuropathy Screening Instrument (MNSI), a validated 15-item self-administered questionnaire, was used to assess DPN in adults ≥18 years with ≥ 5 years of T1D duration. A score of ≥4 was used to define DPN. Diabetes-related characteristics and laboratory data were obtained through the most recent clinic update. Chi-square and t-tests were used to compare demographic and diabetes-related characteristics between those with and without DPN. Linear regression was used to determine the effect of DPN on HbA1c, adjusted for possible confounders. In preliminary analyses of 5,058 participants across 62 sites (mean age 39±18 years, T1D duration 22±14 years, 56% female, 88% non-hispanic white, mean HbA1c 8.1±1.6%), the prevalence of DPN was 10%. Those with DPN were older (52±17 vs. 37±18 years), more likely to be female (61% vs. 55%), had longer T1D duration (32±16 vs. 21±13 years), lower annual household income (37% vs. 59% earning ≥$75K), and lower education level (55% vs. 69% with college degree) than those without DPN (all p<0.001). They also had higher systolic blood pressure (126±17 vs. 123±14 mmHg), triglycerides (117±89 vs. 95±62 mg/dL), tobacco use (9% vs. 4%) and prevalence of established CVD (26% vs. 6%), despite higher use of CVD-modifying agents such as statins (64% vs. 31%) and ACE-inhibitors/ARBs (45% vs. 23%) (all p<0.001). Participants with DPN had higher HbA1c (8.4±1.7% vs. 8.1±1.6%), even after adjusting for multiple confounders (p <0.01). The prevalence of DPN in this national T1D cohort is lower than prior published reports, reflecting current clinical care practices, and highlighting other non-glycemic risk factors for DPN including CVD risk factors and socioeconomic status. Disclosure K.R. Mizokami-Stout: None. C.T. Boyle: None. V.N. Shah: None. G. Aleppo: Research Support; Self; AstraZeneca, Novo Nordisk Inc.. Consultant; Self; Dexcom, Inc.. Advisory Panel; Self; Novo Nordisk Inc. J.B. McGill: Research Support; Self; AstraZeneca. Consultant; Self; Boehringer Ingelheim GmbH. Speaker's Bureau; Self; Aegerion Pharmaceuticals. Consultant; Self; Bayer AG, Dexcom, Inc., Intarcia Therapeutics, Inc.. Speaker's Bureau; Self; Janssen Pharmaceuticals, Inc., MannKind Corporation. Research Support; Self; Novartis Pharmaceuticals Corporation. Consultant; Self; Novo Nordisk A/S. R. Pratley: Other Relationship; Self; AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Eisai Inc., GlaxoSmithKline plc., Janssen Pharmaceuticals, Inc., Lexicon Pharmaceuticals, Inc., Ligand Pharmaceuticals, Inc., Eli Lilly and Company, Merck & Co., Inc., Novo Nordisk Inc., Pfizer Inc., Sanofi-Aventis, Takeda Development Center Americas, Inc.. E. Toschi: None. L. Ang: None. R. Pop-Busui: Research Support; Self; AstraZeneca.