{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T10:29:20Z","timestamp":1789468160207,"version":"build-2803163510"},"reference-count":19,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T00:00:00Z","timestamp":1789430400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Clin. Med.","JCM"],"abstract":"<jats:p>Objective: To compare serum neurofilament light chain (NfL) concentrations between individuals with type 2 diabetes mellitus (T2DM) with and without diabetic polyneuropathy (DPN), and to examine associations with neuropathy burden, balance impairment, fear of falling, and fall history. Methods: This analytical cross-sectional study included 88 participants with T2DM (44 with DPN and 44 without DPN). Serum NfL was measured by enzyme-linked immunosorbent assay (ELISA); neuropathy burden was assessed with the Michigan Neuropathy Screening Instrument (MNSI), balance with the Berg Balance Scale (BBS), and fear of falling with the Falls Efficacy Scale\u2013International (FES-I). Results: Serum NfL was higher in DPN than non-DPN participants [3.47 (2.68\u20134.77) vs. 2.47 (1.48\u20133.07) pg\/mL; p &lt; 0.001]. NfL correlated with MNSI-A (\u03c1 = 0.562), MNSI-B (\u03c1 = 0.550), FES-I (\u03c1 = 0.431), falls (\u03c1 = 0.344), and BBS (\u03c1 = \u22120.450) (all p \u2264 0.001). In the comprehensively adjusted model, the NfL association was attenuated (adjusted odds ratio [aOR] = 1.352; 95% confidence interval [CI], 0.991\u20131.844; p = 0.057). NfL showed moderate discrimination (area under the receiver operating characteristic curve [AUC] = 0.716; 95% CI, 0.607\u20130.825); the internally derived Youden threshold was \u22652.823 pg\/mL (sensitivity 72.7%, specificity 65.9%). Conclusions: NfL may be a complementary marker of DPN-related neuropathy and functional burden, but the adjusted association was attenuated and the study-specific threshold requires external validation. Study Registration: ClinicalTrials.gov identifier NCT07480330. The study was prospectively registered; the initial registry release occurred on 14 March 2026, before study initiation on 25 March 2026.<\/jats:p>","DOI":"10.3390\/jcm15187142","type":"journal-article","created":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T08:16:48Z","timestamp":1789460208000},"page":"7142","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Serum Neurofilament Light Chain in Diabetic Polyneuropathy: Associations with Neuropathy Burden, Balance Impairment, and Fear of Falling"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9010-334X","authenticated-orcid":false,"given":"Zeynep","family":"Karakuzu G\u00fcng\u00f6r","sequence":"first","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, Kanuni Sultan S\u00fcleyman Training and Research Hospital, Istanbul 34303, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5117-528X","authenticated-orcid":false,"given":"M\u00fcrvet","family":"Algemi","sequence":"additional","affiliation":[{"name":"Department of Clinical Biochemistry, Kanuni Sultan S\u00fcleyman Training and Research Hospital, Istanbul 34303, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6416-0183","authenticated-orcid":false,"given":"Hani\u015fe","family":"Ozkan Sonay","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Kanuni Sultan S\u00fcleyman Training and Research Hospital, Istanbul 34303, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"data-curation","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2675-4252","authenticated-orcid":false,"given":"Murat","family":"Akarsu","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Kanuni Sultan S\u00fcleyman Training and Research Hospital, Istanbul 34303, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1296","DOI":"10.1016\/j.neuron.2017.02.005","article-title":"New horizons in diabetic neuropathy: Mechanisms, bioenergetics, and pain","volume":"93","author":"Feldman","year":"2017","journal-title":"Neuron"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1226","DOI":"10.2337\/dc17-0179","article-title":"Prevalence of and risk factors for diabetic peripheral neuropathy in youth with type 1 and type 2 diabetes: SEARCH for Diabetes in Youth Study","volume":"40","author":"Jaiswal","year":"2017","journal-title":"Diabetes Care"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Timar, B., Timar, R., Gai\u021b\u0103, L., Oancea, C., Levai, C., and Lungeanu, D. 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