Cognitive impairment in long-COVID.

Background and purpose:

Long Covid is a complex con­dition characterised by symptoms that per­sist for weeks and months after the Co­vid infection, accompanied by cognitive im­pairment that negatively affects daily life. Understanding this complex condition is im­portant for the development of diagnostic and therapeutic strategies.

This article aims to provide a comprehensive overview of cognitive impairment in long-COVID, including its definition, symptoms, pathophysiology, risk factors, assessment tools, imaging abnormalities, potential biomarkers, management strategies, long-term outcomes, and future directions for research.

The search methodology used in this review aimed to include a wide range of research on cognitive impairment related to both COVID-19 and long-COVID. Systematic searches of PubMed and Google Scholar databases were conducted using a mixture of MeSH terms and keywords including ‘cognition’, ‘cognitive impairment’, ‘brain fog’, ‘COVID-19’ and ‘long-COVID’. The search was restricted to studies published in English between 1 January 2019 and 11 February 2024, which presented findings on neurological manifestations in human participants.

Long-COVID is characterized by persistent symptoms following COVID-19 infection, with cognitive impairment being a prominent feature. Symptoms include brain fog, difficulties with concentration, memory issues, and executive function deficits. Pa­tho­physiological mechanisms involve vi­ral persistence, immune responses, and vas­cular damage. Risk factors include age, pre-existing conditions, and disease seve­rity. Cognitive assessment tools such as the Montreal Cognitive Assessment (MoCA) are essential for diagnosis. Imaging studies, including MRI, PET, and SPECT, reveal structural and functional brain alterations. Potential biomarkers include C-reactive protein, interleukin-6, and neuron-specific enolase. Management strategies encompass cognitive rehabilitation, occupational therapy, medications, and lifestyle modifications.

Long-COVID poses a multifaceted challenge, and cognitive impairment significantly impacts patients’ lives. A multi­disciplinary approach, including cognitive rehabilitation and medication when appropriate, is essential for effective management. Future research should focus on validating biomarkers and understanding long-term cognitive outcomes.

Conclusion – Long-COVID is a global health concern, and cognitive impairment is a distressing symptom. While pharmacological interventions have potential, they require careful consideration. Continued research is crucial for improving the understanding and treatment of cognitive impairment in long-COVID.

Holmes' Tremor with Shoulder Pain Treated by Deep Brain Stimulation of Unilateral Ventral Intermediate Thalamic Nucleus and Globus Pallidus Internus

A 21-year-old male was admitted with severe right arm and hand tremors after a thalamic hemorrhage caused by a traffic accident. He was also suffering from agonizing pain in his right shoulder that manifested after the tremor. Neurologic examination revealed a disabling, severe, and irregular kinetic and postural tremor in the right arm during target-directed movements. There was also an irregular ipsilateral rest tremor and dystonic movements in the distal part of the right arm. The amplitude was moderate at rest and extremely high during kinetic and intentional movements. The patient underwent left globus pallidum internus and ventral intermediate thalamic nucleus deep brain stimulation. The patient improved by more than 80% as rated by the Fahn-Tolosa-Marin Tremor Rating Scale and Visual Analog Scale six months after surgery.