Background: Dementia is a decline in cognitive abilities of sufficient severity to interfere with activities of daily living and is not caused by delirium or other medical or psychiatric disorder. The subset of Very Young Onset Dementia (VYOD) with onset before 25 years is not studied well in India. In this study we aimed at describing the clinical profile, higher mental functions, investigations and etiological factors in these patients. Methodology: We conducted an observational, retrospective, single-cohort study to study the clinical profile of dementia patients presenting to the Department of Neurology at Topiwala National Medical College & BYL Nair Charitable Hospital, Mumbai. We searched for patients with dementia with onset between 10 to 25 years. We collected patient related demographic and clinical information from the records. All the collected data will be entered in Microsoft excel sheet and imported in to Statistical Package for Social Sciences (SPSS) version 16 for statistical analalysis. Results: 21 patients were included in the study, 18 males, average age of onset is 13.1 years. Subacute Sclerosing Panencephalitis, Hereditary Spastic Paraplegias, Wilson’s disease were common aetiologies. 33% patients had Mini Mental Status Examination score of less than 10. 42% patients had Frontal Assessment Battery score less than 5. 42% patients had frontal, temporal and parietal lobes involvement. MRI brain was abnormal and revealed T2 hyperintensity in basal ganglia, brainstem and cerebellum. Conclusion: Early onset dementia is an underestimated problem in developing countries. Preventable conditions such as Subacute Sclerosing Panencephalitis (SSPE) and treatable condition such as Wilson’s disease (WD) are leading causes in dementia with onset before 25 years. Awareness of these conditions is important while evaluating patients with VYOD.

Keywords: Dementia; Wilson’s disease (WD); Very Young Onset Dementia (VYOD); Subacute Sclerosing Panencephalitis (SSPE).