<prompt> Most common cause of dementia is -Alzhiemers diseaseVascular dementiaWilsons diseasePicks disease  <response>: Ans. is a i.e., Alzhiemers diseaseCauses of dementiaReversible causes Surgically treatableo Normal pressure hydrocephaluso Brain tumors frontal lobe tumoro Meningiomao Subdural hematoma Head injuryo HydrocephalusMedically treatable o Hypothyroidismo Depressiono HIV infectiono Alcohol abuseo Vitamin B12 , Folate. Niacin deficiencyo Any metabolic or endocrine disturbanceo Neurosyphiliso Hashimotos encephalopathyo Wilsons diseaseo Celiac disease or Whipples diseaseo Chronic meningoencephalitiso Drugs and toxin toxic dementiaIrreversible causeso Alzheimer s diseaseo Vascular Multi-infarct dementia o Parkinsons diseaseo Huntingtons choreao Creutzfeld Jakob diseaseo Lewy body dementiao Picks diseaseo Overall Alzheimers disease is the most common cause. Vascular dementia is the 2nd most common cause. 