Cholinesterase Inhibitors in Non-age Related Neurodegenerative Dementias

Aims: Dementia is common among the elderly but it can also affect the younger age group. Cholinesterase inhibitors (ChEI) in Alzheimer Dementia (AD) are extensively studied and widely used. This case report aims to illustrate the usefulness of ChEIs in other non–age related neurodegenerative dementias apart from AD.

Presentation of Cases: Four cases in which ChEIs was found to be useful in improving the cognition following Traumatic Brain Injury, Nipah Encephalitis, Cerebral Malaria and Meningo-encephalitis. All the four cases were prescribed ChEIs and were followed up in a Memory Clinic. All of them showed substantial and sustained cognitive improvement.

Discussion: Traumatic brain injury causes axonal swelling with accumulation of beta-amyloid and alters progranulin metabolism. Nipah Virus infection of brain parenchyma causes vasculitis, endothelial damage and micro-infarction. While in cerebral malaria, infected and non-infected erythrocytes within the cerebral vessels reduces microvascular flow and initiates inflammatory cascade. Infective encephalitis causes neurotoxin production and inflammatory process. These pathological processes reduce cerebral neurotransmitters concentration including acetylcholine. Cholinesterase inhibitors enhance cognitive function by increasing the amount of acetylcholine at the neuronal synaptic cleft. This clinical significance may be extended to patients with cognitive impairments other than AD.

Conclusion: This report highlights the usefulness of ChEI in non–age related neurodegenerative dementias. Off label use of ChEI in non-AD dementias warrant proper clinical trials to recommend for clinical practice.