Sex differences in neuropathic pain in longstanding diabetes: Results from the Canadian Study of Longevity in Type 1 Diabetes

Aim: Neuropathy and neuropathic pain are common complications of type 1 diabetes (T1D). We aimed to determine if sex-specific differences in neuropathic pain are present in adults with longstanding T1D. Methods: Canadians with >= 50 years of T1D (n = 361) completed health history questionnaires that included assessment of neuropathy (defined by Michigan Neuropathy Screening Instrument questionnaire components >= 3; NEUROPATHY(MNSI-Q)) and neuropathic pain. Multivariable logistic regression was used to determine sex-differences in neuropathic pain controlling for neuropathy. Results: Participants had mean age 66 +/- 9 years, median diabetes duration 53[51,58] years, mean HbA1c 7.5 +/- 1.0%, and 207(57%) were female. Neuropathic pain was present in 128(36%) of all participants, more prevalent among those with NEUROPATHY(MNSI-Q) compared to those without [96(63%) vs. 31(15%), p < 0.001], and more prevalent in females compared to males [87(42%) vs. 41(27%), p = 0.003]. Independent of the presence of NEUROPATHY(MNSI-Q) and other factors, female sex was associated with the presence of neuropathic pain [OR 2.68 (95% CI 1.4-5.0), p = 0.002]. Conclusions: We demonstrated a novel sex-specific difference in neuropathic pain in females compared to males with longstanding T1D, independent of the presence of neuropathy. Further research using more objective measures of neuropathy than the MNSI is justified to further understand this sex-specific difference. (c) 2018 Elsevier Inc. All rights reserved.