TWO DISTINCT MECHANISMS, ONE OUTCOME: ELECTROPHYSIOLOGICAL TRACES OF PERIPHERAL NERVES IN DIABETES MELLITUS AND RHEUMATOID ARTHRITIS

Year 2025, Volume: 6 Issue: 3, 297 - 303, 25.11.2025

Yağmur İnalkaç Gemici , Berfin Cansel Atıcı , Ayşegül Şeyma Sarıtaş , Hatice Mavioğlu

Abstract

Introduction: Diabetes mellitus (DM) and rheumatoid arthritis (RA) affect the peripheral nervous system through distinct mechanisms, leading to polyneuropathy (PNP). This study compared nerve conduction studies in DM and RA patients, evaluating subgroups by PNP status.

Methods: Electrophysiological examinations performed between 2015 and 2025 were retrospectively reviewed, including 208 DM and 96 RA patients. Motor and sensory conduction parameters of the median, ulnar, sural, and fibular nerves were assessed. Patients were classified as PNP+ or PNP–. Group differences were analyzed, risk factors identified with logistic regression, and significant parameters tested with ROC analysis.

Results: In DM, conduction velocities were reduced, distal latencies prolonged, and amplitudes decreased (p<0.05). In RA, parameters were relatively preserved, with higher amplitudes than DM. Among PNP+ patients, DM showed more severe involvement; sural nerve velocity <34.5 m/s was discriminatory for DM (AUC=0.771; specificity 85.1%) from RA. In RA, PNP was mainly sensory and strongly associated with female sex (OR=7.51, 95% CI: 3.36–16.80). In PNP– patients, no major differences were found, though RA showed entrapment/demyelinating features and DM subclinical small fiber involvement.

Conclusion: DM is characterized by widespread axonal degeneration, whereas RA presents heterogeneous and milder neuropathic patterns. These differences may aid differential diagnosis and prognostic evaluation. Sural nerve conduction velocity appears particularly promising as a biomarker


Conclusion: DM is characterized by widespread axonal degeneration, whereas RA presents heterogeneous and milder neuropathic patterns. These differences may aid differential diagnosis and prognostic evaluation. Sural nerve conduction velocity appears particularly promising as a biomarker.

Keywords

Diabetes Mellitus , Rheumatoid Arthritis , Nerve Conduction Study , Polyneuropathy , Ulnar Sensory Conduction

Ethical Statement

Prior to the initiation of the study, approval was obtained from the local ethics committee (No. 20.478.486/3420, dated September 24, 2025).

Supporting Institution

None

Thanks

None

İKİ FARKLI MEKANIZMA, TEK SONUÇ: DİYABETES MELLİTUS VE ROMATOİD ARTRİTTE PERİFERİK SİNİRLERİN ELEKTROFIZYOLOJİK İZLERİ

Abstract

Amaç: Diyabetes mellitus (DM) ve romatoid artrit (RA), periferik sinir sistemini farklı patofizyolojik mekanizmalarla etkileyerek polinöropatiye (PNP) yol açabilmektedir. Bu çalışmada, DM ve RA hastalarında sinir iletim çalışmalarının karşılaştırılması ve PNP varlığına göre alt grupların değerlendirilmesi amaçlanmıştır.

Yöntem: 2015–2025 yılları arasında yapılan retrospektif elektrofizyolojik incelemeler taranarak, 208 DM ve 96 RA hastası dahil edilmiştir. Median, ulnar, sural ve fibular sinirlerde motor ve duysal iletim parametreleri değerlendirilmiştir. Hastalar PNP saptananlar (PNP+) ve saptanmayanlar (PNP–) olarak ikiye ayrılarak analiz edilmiştir. Gruplar arası farklılıklar karşılaştırılmış, risk faktörleri lojistik regresyonla belirlenmiş ve anlamlı parametreler için ROC analizi uygulanmıştır.

Bulgular: DM grubunda iletim hızları belirgin şekilde düşük, distal latanslar uzun, amplitüdler azalmıştı (p<0,05). RA grubunda parametreler görece korunmuştu, özellikle amplitüd değerleri DM’ye kıyasla daha yüksekti. PNP+ alt grupta DM hastaları daha ağır etkilenmiş, sural sinir iletim hızının <34,5 m/sn olması DM için RA’dan ayırt edici bulunmuştur (AUC=0,771; spesifite %85,1). RA’da ise PNP daha çok duyusal tipte olup kadın cinsiyetle ilişkiliydi (OR=7,51, %95 GA: 3,36–16,80). PNP– alt grupta gruplar arasında belirgin fark izlenmezken, RA’da entrapment/demyelinizan özellikli değişiklikler, DM’de ise subklinik küçük lif tutulumuna işaret eden bulgular dikkat çekmiştir.

Sonuç: DM’de yaygın aksonal dejenerasyon, RA’da ise heterojen ve görece hafif nöropati paternleri ön plandadır. Bu farklılıkların ayırıcı tanı ve prognoz öngörüsünde klinik olarak yol gösterici olabileceği, özellikle sural sinir iletim hızının biyobelirteç potansiyeli taşıdığı düşünülmektedir

Keywords

Diyabetes Mellitus , Romatoid Artrit , Sinir iletim çalışması , Polinöropati , Ulnar duysal iletim

Ethical Statement

Çalışma başlamadan önce yerel etik kuruldan onay (24.09.2025 tarihli 20.478.486/3420 numaralı) alınmıştır.

Supporting Institution

Yoktur

Thanks

Yoktur

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