PDF herunterladen
Open Access
CC BY 4.0 · Arq Neuropsiquiatr 2025; 83(12): s00451813243
DOI: 10.1055/s-0045-1813243
Original Article

Electrophysiological and biochemical evaluations of neuropathy risk in oral levodopa versus levodopa/carbidopa intestinal gel treatment

Autor*innen

  • Miray Erdem 

    1   Health Sciences University, Adana City Training and Research Hospital, Department of Neurology, Adana, Türkiye.

  • Bugra Selluncak 

    1   Health Sciences University, Adana City Training and Research Hospital, Department of Neurology, Adana, Türkiye.

  • Mehmet Balal 

    2   Cukurova University, Faculty of Medicine, Department of Neurology, Adana, Türkiye.

  • Halit Fidanci 

    3   Health Sciences University, Adana City Training and Research Hospital, Department of Neurology, Division of Neurophysiology, Adana, Türkiye.

  • Meltem Demirkiran 

    2   Cukurova University, Faculty of Medicine, Department of Neurology, Adana, Türkiye.
Weitere Informationen
Auch verfügbar auf
  Lizenzen und Reprints

Abstract

Background

The association between levodopa treatment and neuropathy in Parkinson's disease (PD) remains controversial, particularly when comparing the oral and intestinal administration routes.

Objective

To compare the electrophysiological and biochemical changes in patients receiving oral levodopa or levodopa/carbidopa intestinal gel (LCIG) and to determine their association with neuropathy development.

Methods

The current prospective cross-sectional study included 32 PD patients (18 oral and 14 LCIG). Demographic features, disease duration, Hoehn and Yahr (H&Y) stage, Unified Parkinson's Disease Rating Scale (UPDRS) scores, biochemical parameters (vitamin B12, folate, homocysteine), and electrophysiological values were recorded. Nerve conduction studies (NCSs) of the median, ulnar, peroneal, tibial, and sural nerves were performed unilaterally, using reference values from our neurophysiology laboratory.

Results

The LCIG group presented significantly higher doses of levodopa (p < 0.001), levodopa equivalent daily dose (LEDD; p < 0.001), and homocysteine levels (p = 0.002) compared with the oral group. Electrophysiological tests revealed significantly reduced motor amplitudes and sensory conduction velocities in the median, ulnar, tibial, and sural nerves in the LCIG group. The median and tibial F-wave latencies were prolonged in the LCIG group. Correlation analyses indicated significant associations involving homocysteine elevation and conduction abnormalities.

Conclusion

Patients receiving LCIG presented higher homocysteine levels and more frequent electrophysiological abnormalities than those on oral treatment, suggesting a higher risk of polyneuropathy. These findings highlight the importance of biochemical monitoring and individualized treatment strategies in advanced PD.

Keywords

Levodopa - Carbidopa - Parkinson Disease - Polyneuropathies

Authors' Contributions

Conceptualization: ME, BS, MB, HF, MD; Formal analysis: ME, BS, MB, HF, MD; Investigation: ME, BS, MB, HF, MD; Methodology: ME, BS, MB, HF, MD; Resources: ME, BS, MB, HF, MD; Writing – original draft: ME, BS, MB, HF, MD; Writing – review & editing: ME, BS, MB, HF, MD.


Data Availability Statement

Data will be available upon request to the corresponding author.


Editor-in-Chief: Hélio A. G. Teive (https://orcid.org/0000-0003-2305-1073).


Associate Editor: Renato Puppi Munhoz (https://orcid.org/0000-0002-4783-4067).




Publikationsverlauf

Eingereicht: 14. Juli 2025

Angenommen: 18. September 2025

Artikel online veröffentlicht:
08. Dezember 2025

© 2025. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution 4.0 International License, permitting copying and reproduction so long as the original work is given appropriate credit (https://creativecommons.org/licenses/by/4.0/)

Thieme Revinter Publicações Ltda.
Rua Rego Freitas, 175, loja 1, República, São Paulo, SP, CEP 01220-010, Brazil

Bibliographical Record
Miray Erdem, Bugra Selluncak, Mehmet Balal, Halit Fidanci, Meltem Demirkiran. Electrophysiological and biochemical evaluations of neuropathy risk in oral levodopa versus levodopa/carbidopa intestinal gel treatment. Arq Neuropsiquiatr 2025; 83: s00451813243.
DOI: 10.1055/s-0045-1813243