This report provides a comprehensive overview of dementia, a chronic illness characterized by the degeneration and loss of cognitive function, primarily affecting the elderly. It delves into the various risk factors associated with dementia, including age, alcohol abuse, diabetes mellitus, and genetic predispositions. The report explores the pathophysiology, aetiology, clinical manifestations, and diagnostic tests used to identify dementia. Furthermore, it examines the treatment approaches, encompassing pharmacological and non-pharmacological interventions, along with the importance of person-centered care and interdisciplinary units. A case study of a 75-year-old female with Alzheimer's disease-related dementia is presented to illustrate the practical implications of dementia and the role of nursing care. The report emphasizes the chronic nature of dementia, its impact on the quality of life, and the significance of providing comprehensive care, including palliation and support for both patients and their families. The report also references several studies and research papers to support its findings and recommendations.