Evaluation of Nerve Conduction and Cognitive Function in Hypothyroidism and their Correlation with Serum Neurofilament Light Chain

Arwa Raid Hammodat; Hanan Luay Al-Omary; Omar Farooq Nafea Al-Azzawi

doi:10.54133/ajms.v9i1.2081

Authors

Arwa Raid Hammodat Department of Physiology, College of Medicine, University of Baghdad, Baghdad, Iraq https://orcid.org/0009-0001-8579-1264
Hanan Luay Al-Omary Department of Physiology, College of Medicine, University of Baghdad, Baghdad, Iraq https://orcid.org/0000-0001-5686-6178
Omar Farooq Nafea Al-Azzawi Department of Medicine, College of Medicine, University of Baghdad, Baghdad, Iraq https://orcid.org/0000-0002-8457-0064

DOI:

https://doi.org/10.54133/ajms.v9i1.2081

Keywords:

Enzyme-linked immunosorbent assay, Hypothyroidism, Montreal cognitive assessment, Nerve conduction study, Serum neurofilament light chain

Abstract

Background: Hypothyroidism is an endocrine disorder defined by insufficient amounts of thyroid hormone. It can affect the peripheral nervous system, evaluated using electrodiagnostic studies and serum neurofilament light chain (NfL), a biomarker of neuronal injury. Cognitive function, including memory and attention, may also be impaired and assessed using the Montreal Cognitive Assessment (MoCA) tool. Objectives: To assess peripheral neuropathy and cognitive dysfunction in hypothyroid patients and to evaluate their association with serum NfL levels. Methods: A case-control study was conducted at Ghazi Al-Hariri Hospital in Baghdad from August 1, 2024, to April 1, 2025, involving 40 hypothyroid patients and 40 controls. All participants underwent sensory and motor nerve conduction studies and MoCA assessment. Serum NfL levels were measured in 20 patients and 20 controls using the ELISA technique. Results: Hypothyroid patients showed significantly higher serum NfL levels (26.49±8.18pg/mL) compared to controls (9.6±1.64pg/mL; p<0.001). Nerve conduction studies revealed slower conduction velocities and prolonged latencies, particularly in the median and sural nerves (p<0.001). Cognitive dysfunction (MoCA < 26) was found in 47.5% of hypothyroid patients and was associated with higher NfL levels (30.23±7.49pg/mL vs. 20.87± 5.77pg/mL; p=0.008). Conclusions: Hypothyroidism is associated with peripheral neuropathy and cognitive impairment, both linked to elevated serum NfL levels. NfL may serve as a non-invasive biomarker for neurological complications in hypothyroid patients

Downloads

Download data is not yet available.

References

Chaker L, Razvi S, Bensenor IM, Azizi F, Pearce EN, Peeters RP. Hypothyroidism. Nat Rev Dis Primers. 2022;8(1):1–19. doi: 10.1038/s41572-022-00357-7. DOI: https://doi.org/10.1038/s41572-022-00357-7

Sweeney T, O’Sullivan J, O’Doherty JV. Thyroid hormone regulation and its effects on human health. Endocr Rev. 2020;41(6):890–907. doi: 10.1210/endrev/bnaa024. DOI: https://doi.org/10.1210/endrev/bnaa024

Bouillon R, Marcocci C, Rizzoli R, Giustina A. The thyroid hormone pathway: Regulation and implications for thyroid disease. Nat Rev Endocrinol. 2021;17(8):474–486. doi: 10.1038/s41574-021-00503-3. DOI: https://doi.org/10.1038/s41574-021-00503-3

Sudek HL. The effect of thyroxine treatment in infertile subclinical hypothyroid patients. J Fac Med Baghdad. 2011;53(3):343–347. doi: 10.32007/jfacmedbagdad.533845. DOI: https://doi.org/10.32007/jfacmedbagdad.533845

Zamwar UM, Muneshwar KN. Epidemiology, types, causes, clinical presentation, diagnosis, and treatment of hypothyroidism. Cureus. 2023;15(9):e46241. doi: 10.7759/cureus.46241. DOI: https://doi.org/10.7759/cureus.46241

Ali EA, Hussein HKA, Tahssen YH. Estimation of serum copper, manganese, selenium, and zinc in hypothyroid patients. J Fac Med Baghdad. 2008;50(2):255–260. doi: 10.32007/jfacmedbagdad.5021291. DOI: https://doi.org/10.32007/jfacmedbagdad.5021291

Rasheed NH, Al-Metwali BZ, Al Shamaa MSM. Evaluation of anxiety and depression among a sample of hypothyroidism-treated Iraqi patients. Iraqi J Pharm Sci. 2023;32(2):162–168. doi: 10.31351/vol32iss2pp162-168. DOI: https://doi.org/10.31351/vol32iss2pp162-168

Parvatha Rani N, Sudha S, Balasubramaniam K. Nerve conduction study in newly diagnosed female hypothyroid patients – A cross-sectional study. Int J Acad Med Pharm. 2024;6(1):935–938. doi: 10.47009/jamp.2024.6.1.184.

Sawicka-Gutaj N, Zawalna N, Gut P, Fischli S, Czarnywojtek A. Relationship between thyroid hormones and central nervous system metabolism in physiological and pathological conditions. Pharmacol Rep. 2022;74(4):847–858. doi: 10.1007/s43440-022-00377-w. DOI: https://doi.org/10.1007/s43440-022-00377-w

Shaji B, Joel JJ. Impact of hypothyroidism on metabolic and cognitive dysfunction: A comprehensive review. J Young Pharm. 2022;14(4):349–354. doi: 10.5530/jyp.2022.14.71. DOI: https://doi.org/10.5530/jyp.2022.14.71

Montaño-Lozada J, López N, Espejo-Zapata L, Soto-Añari M, Ramos-Henderson M, Caldichoury-Obando N, et al. Cognitive changes in patients with epilepsy identified through the MoCA test. Epilepsy Behav. 2021;122:108158. doi: 10.1016/j.yebeh.2021.108158. DOI: https://doi.org/10.1016/j.yebeh.2021.108158

Gupta N, Arora M, Sharma R, Arora KS. Peripheral and central nervous system involvement in recently diagnosed cases of hypothyroidism: An electrophysiological study. Ann Med Health Sci Res. 2016;6(5):261–266. doi: 10.4103/amhsr.amhsr_39_16. DOI: https://doi.org/10.4103/amhsr.amhsr_39_16

Meshram K, Rawekar A, Meshram A, Meshram H, Vaggha A, Ingle S. Nerve conduction study in early diagnosed cases of hypothyroidism in Central India. Indian J Forensic Med Toxicol. 2020;14(4):12760. doi: 10.37506/ijfmt.v14i4.12760. DOI: https://doi.org/10.37506/ijfmt.v14i4.12760

Jones LK. Nerve conduction studies: basic concepts and patterns of abnormalities. Neurol Clin. 2012;30(2):405–427. doi: 10.1016/j.ncl.2011.12.002. DOI: https://doi.org/10.1016/j.ncl.2011.12.002

Widyadharma IPE, Tedyanto EH. Serum neurofilament light chain: A potential biomarker for peripheral neuropathy. Singapore Med J. 2022;74(10):714–720. doi: 10.33192/smj.2022.84. DOI: https://doi.org/10.33192/Smj.2022.84

Maalmi H, Strom A, Petrera A, Hauck SM, Strassburger K, Kuss O, et al. Serum neurofilament light chain: A novel biomarker for early diabetic sensorimotor polyneuropathy. Diabetologia. 2022;66(3):579–589. doi: 10.1007/s00125-022-05846-8. DOI: https://doi.org/10.1007/s00125-022-05846-8

Fundaun J, Kolski M, Molina-Álvarez M, Baskozos G, Schmid AB. Types and concentrations of blood-based biomarkers in adults with peripheral neuropathies: A systematic review and meta-analysis. JAMA Netw Open. 2022;5(12):e2248593. doi: 10.1001/jamanetworkopen.2022.48593. DOI: https://doi.org/10.1001/jamanetworkopen.2022.48593

Jing X, Wang L, Song M, Geng H, Li W, Huo Y, et al. Serum neurofilament light chain and inflammatory cytokines as biomarkers for early detection of mild cognitive impairment. Sci Rep. 2024;14(1):45930. doi: 10.1038/s41598-024-59530-5. DOI: https://doi.org/10.1038/s41598-024-59530-5

Nasreddine ZS. The montreal cognitive assessment (MoCA): A brief screening tool for mild cognitive impairment. MoCA Cognition. Available at: https://mocacognition.com/paper/

Alkzaz R, Al-Omary HL. Correlation between cognition and quantitative EEG changes in patients with migraine. J Fac Med Baghdad. 2024;65(4). doi: 10.32007/jfacmedbagdad.2151. DOI: https://doi.org/10.32007/jfacmedbagdad.2151

Ibraheem RM, Hamdi RA, Kadam SM. Measurement of serum stromelysin-2 level in Iraqi patients with subclinical and clinical hypothyroidism. J Fac Med Baghdad. 2024;66(1):67–72. doi: 10.32007/jfacmedbagdad.6612177. DOI: https://doi.org/10.32007/jfacmedbagdad.6612177

Sulaiman TI, Al-Sarraf SA, Al-Rrawak K. Changing patterns of thyroid pathology and trends of surgical treatment. J Fac Med Baghdad. 2009;51(1). doi: 10.32007/jfacmedbagdad.5111159. DOI: https://doi.org/10.32007/jfacmedbagdad.5111159

Møllehave LT, Jacobsen RK, Linneberg A, Skaaby T, Knudsen N, Jørgensen T, et al. Influence of educational level on test and treatment for incident hypothyroidism. Clin Endocrinol (Oxf). 2021;94(6):1025–34. https://doi.org/10.1111/cen.14429 DOI: https://doi.org/10.1111/cen.14429

Sinha RA, Singh BK, Yen PM. Thyroid hormone regulation of adult brain function. Endocr Rev. 2022;43(1):1–30. doi: 10.1210/endrev/bnaa034. DOI: https://doi.org/10.1210/endrev/bnaa034

Bhat AN, Hegde A, Shetty VT, Kamath A. Neuromuscular complications of hypothyroidism: An electrophysiological and biochemical correlation. Ann Indian Acad Neurol. 2021;24(2):193–199. doi: 10.4103/aian.AIAN_791_20. DOI: https://doi.org/10.4103/aian.AIAN_791_20

Mishra J, Vishwakarma J, Malik R, Upadhyay A. Hypothyroidism induces interleukin-1-dependent autophagy mechanism as a key mediator of hippocampal neuronal apoptosis and cognitive decline. Mol Neurobiol. 2021;58(3):1103–1116. doi: 10.1007/s12035-020-02178-9. DOI: https://doi.org/10.1007/s12035-020-02178-9

Khalil M, Teunissen CE, Otto M, Piehl F, Sormani MP, Gattringer T, et al. Neurofilaments as biomarkers in neurological disorders: Towards clinical application. Nat Rev Neurol. 2024;20(5):269–287. doi: 10.1038/s41582-024-00955-x. DOI: https://doi.org/10.1038/s41582-024-00955-x

Romano A, Plantone D, Capone F, Di Lazzaro V. Serum neurofilament light chain: A promising early diagnostic biomarker for hereditary transthyretin amyloidosis? Eur J Neurol. 2024;31(1):e16070. doi: 10.1111/ene.16070. DOI: https://doi.org/10.1111/ene.16070