EC Pulmonology and Respiratory Medicine

Review Article Volume 14 Issue 5 - 2025

Cognitive Function Assessment Using the Stroop Test: Exploring the Broader Therapeutic Potential of L-Ornithine L-Aspartate (LOLA, Hepa-Merz), a Hepatic Encephalopathy Medication

Petar Avramovski1*, Emilija Parisko2, Maja Avramovska3, Pece Stefanovski4, Zorica Nikleski5, Liljana Todorovska6, Biljana Taleva7, Svetlana Stefanovska8, Vesna Siklovska9, Ilija Kelepurovski10, Kosta Sotiroski11 and Dejan Zdraveski11

1Department of Internal Medicine, University St. Clement of Ohrid - Bitola, Clinical Hospital - Bitola, North Macedonia

2Department of Cardiology, Clinical Hospital - Bitola, North Macedonia

3Affiliated Researcher (Under Mentorship for License Renewal), North Macedonia

4Medico - Legal Department, MedAssess, Sydney, New South Wales, Australia

5Department of Nuclear Medicine, Clinical Hospital “D-r Trifun Panovski” - Bitola, Bitola, North Macedonia

6Department of Children Surgery, "Mother Teresa University Clinic-Skopje", Skopje, North Macedonia

7Department of Gastroenterology, Clinical Hospital - Bitola, North Macedonia

8Department of Children Surgery, "Mother Teresa University Clinic-Skopje", Skopje, North Macedonia

9Department of Radiology, Clinical Hospital - Bitola, North Macedonia

10Department of Urology, Clinical Hospital - Bitola, North Macedonia

11Department of Business Informatics, Faculty of Economics - Prilep, “St. Kliment Ohridski” - University, Bitola, North Macedonia

*Corresponding Author: Petar Avramovski, Department of Internal Medicine, University St. Clement of Ohrid - Bitola, Clinical Hospital - Bitola, North Macedonia.
Received: April 02, 2025; Published:April 11, 2025



Background: L-Ornithine L-Aspartate (LOLA), known commercially as Hepa-Merz, is widely used in the treatment of hepatic encephalopathy (HE) due to its ability to facilitate ammonia clearance via both urea and glutamine pathways. In addition to its established role in HE, emerging evidence suggests LOLA may aid liver regeneration, support mitochondrial function, and reduce oxidative stress. This study investigates LOLA's potential impact on cognitive performance in individuals with minimal hepatic encephalopathy (MHE), utilizing the Stroop Test as a neuropsychological evaluation tool and correlating findings with serum ammonia concentrations.

Methods: Sixty-five patients diagnosed with MHE underwent cognitive evaluation before and after administration of LOLA. Ammonia levels were quantified both pre- and post-intervention. The Stroop Test, including Stroop Word (SW), Stroop Color (SC), Stroop Color-Word (SCW), and the Total Stroop Test (TST), was used to assess changes in cognitive speed and accuracy. Data were analyzed using unpaired t-tests to evaluate the significance of observed changes.

Results: Post-treatment results showed a significant decrease in blood ammonia levels (from 123.2 ± 27.1 µmol/L to 112.7 ± 24.1 µmol/L, p < 0.05). All Stroop Test components demonstrated marked improvement, with faster TST indicating better cognitive processing. Moreover, patients with initially elevated ammonia levels tended to perform worse on cognitive testing, reinforcing the link between hyperammonemia and cognitive dysfunction.

Conclusion: Hepa-Merz demonstrates efficacy in reducing systemic ammonia and enhancing cognitive function in MHE patients. The Stroop Test proves to be a sensitive and practical measure for detecting neurocognitive changes and treatment effects. These findings support further exploration of LOLA’s (Hepa-Merz) benefits beyond traditional HE management, particularly in preserving or improving brain function.

 Keywords: L-Ornithine L-Aspartate; Hepatic Encephalopathy; Ammonia Detoxification; Cognitive Function; Stroop Test; Minimal Hepatic Encephalopathy; Hepa-Merz

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Petar Avramovski., et al. "Cognitive Function Assessment Using the Stroop Test: Exploring the Broader Therapeutic Potential of L-Ornithine L-Aspartate (LOLA, Hepa-Merz), a Hepatic Encephalopathy Medication". EC Pulmonology and Respiratory Medicine  14.5 (2025): 01-10.

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