The role of Orexin-A levels in epileptic seizure

doi:10.1016/j.neulet.2020.135097

Neuroscience Letters

Volume 734, 24 August 2020, 135097

https://doi.org/10.1016/j.neulet.2020.135097 Get rights and content

Highlights

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Epileptic seizures are often confused with psychogenic non-epileptic seizures.
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True diagnoses often come late in psychogenic non-epileptic seizures patients.
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Delay in diagnostic procedures can cause patients to unnecessarily use many antiepileptic drugs Therefore, it is important to establish the differential diagnosis of epilepsy and non-epileptic seizures patients in the early period.
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Blood orexin levels may be an effective biomarker in the differential diagnosis of epileptic seizures and non-epileptic seizures patients.

Abstract

Background

The aim of this study is to determine the usefulness of Orexin-A levels in differentiating between epileptic seizures and psychogenic non-epileptic seizures in patients presenting to the emergency service with epileptic seizure-type symptoms.

Methods

A total of 80 individuals were included in this study, including 59 who presented to the emergency service within the first four hours of having been diagnosed with generalized tonic-clonic seizures (39 with epileptic seizures (ES) and 20 with pseudoseizures (PNES) and 21 controls. Orexin-A levels were measured in venous blood samples.

Results

The mean Orexin-A levels were 5.16 ng/mL in the control group, 7.17 ng/mL in the PNES group, and 11.08 ng/mL in the ES group (Table 1). The mean Orexin-A level of the ES group was significantly different from both the control group and the PNES group (Table 1, p < 0.001); the difference between the control group and the PNES group was not significant (p > 0.05).

Conclusions

Results of this study suggest that blood Orexin-A may be an effective biomarker in the differential diagnosis of epileptic seizures/psychogenic non-epileptic seizures in patients presenting to the emergency service with an epileptic seizure-type clinical picture.

Section snippets

Background

Epilepsy is a disease characterized by seizures that are caused by abnormal and excessive electrical discharges in the cortical neurons [1,2]. Epileptic seizures (ES) are often confused with psychogenic non-epileptic seizures (PNES) because of their clinical similarities [3].

PNES are commonly observed in epilepsy centers [4]. PNES are similar to ES with regards to paroxysmal changes in reaction, movement, and behavior; however, PNES differ from ES in that they are not accompanied by

Study design and patient population

This study was conducted between March 1, 2015 and September 30, 2015 in the Emergency Service of Sakarya University Training and Research Hospital. The serum samples of patients who presented due to seizure and who were at least 15 years old were evaluated. A total of 65 patients who had been diagnosed with epilepsy which was present for more than one year. A total of 26 patients were excluded from the study due to the following: secondary generalized seizure; complex partial seizure; status

Results

A total of 80 individuals (39 ES, 20 PNES, and 21 controls) were included in this study. Mean age of subjects with ES was 3207 ± 1373 years, mean age of subjects with PNES was 3171 ± 1201 years and mean age of subjects with control group was 3266 ± 11,65.

The distribution of patients and the mean age of each group are presented in Table 1. Mean time delay between seizure and blood draw was 2,4 ± 1.2 h (range 0−4 hours). There was no correlation between duration and Orexin-A levels (p > 0.05).

The

Discussion

Epilepsy is one of the biggest neurological problems worldwide [9]. ES is often confused with PNES because they share many clinical similarities [3]. PNES is commonly observed in epilepsy centers [4]. PNES consist of paroxysmal changes similar to epileptic seizures in reaction, movement, or behavior; however, they have no neurobiological origin and are not accompanied by the electrophysiological changes seen in ES [[5], [6], [7]]. EEG is an easy and inexpensive method for the diagnosis and

Conclusion

Blood orexin levels in ES patients were significantly higher than those in the control and PNES groups. This result suggests that blood orexin levels may be an effective biomarker in the differential diagnosis of ES and PNES. Further studies are necessary for clinical use.

Authors’ contributions

HIC, conceived of the study, participated in its design and coordination of the study and wrote the paper. DK, participated in the design of the study and wrote the paper. MY, participated in the design of the study and wrote the paper. MC, collected the data’s. OFB, collected the data’s. GGC, carried out the immunoassays. IHC, performed the statistical analysis. All authors read and approved the final manuscript.

CRediT authorship contribution statement

Halil Ibrahim Çikriklar: Investigation, Project administration, Supervision, Writing - original draft. Dilcan Kotan: Resources, Writing - original draft, Methodology. Murat Yücel: Visualization, Writing - original draft, Methodology. Mustafa Ceylan: Resources, Writing - review & editing. Gönül G. Çiftçi: Visualization, Writing - review & editing. Ömer F. Bayraktutan: Resources. Ihsan H. Çiftçi: Formal analysis.

Declaration of Competing Interest

There are no conflicts of interest.

Acknowledgement

We would like to express our deepest gratitude to the staff of the Emergency Service of Sakarya University Training and Research Hospital who took care of patients.

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Research articleThe role of Orexin-A levels in epileptic seizure

Highlights

Abstract

Background

Methods

Results

Conclusions

Section snippets

Background

Study design and patient population

Results

Discussion

Conclusion

Authors’ contributions

CRediT authorship contribution statement

Declaration of Competing Interest

Acknowledgement

Neuroimaging Clin. N. Am.

Seizure

Epilepsy Behav.

Seizure

Seizure

Epilepsy Behav.

Neuropharmacology.

Brain Res.

Sleep Med. Rev.

Sleep Med.

Trends Neurosci.

Neurobiol. Dis.

Peptides

Peptides

Brain Res.

Peptides

Research article
The role of Orexin-A levels in epileptic seizure