Most common cause of dementia is-

Appeared in: RUHS, Jaipur, PB B.Sc Nursing Entrance-2024

Explanation

Alzheimer's disease is the most prevalent form of dementia, accounting for 50-60% of all cases.
It is a progressive neurodegenerative disorder characterized by the gradual deterioration of cognitive functions, most notably memory.
The disease involves the formation of amyloid plaques and neurofibrillary tangles, leading to widespread neuronal loss and brain atrophy.
While other conditions can cause cognitive symptoms, Alzheimer's is the leading cause of a chronic, progressive dementia syndrome.

Option B: Acid-base imbalances cause acute metabolic encephalopathy or delirium, not chronic, progressive dementia. The symptoms are typically reversible with correction of the imbalance.
Option C: Similar to acid-base issues, electrolyte imbalances (e.g., hyponatremia, hypercalcemia) lead to delirium or an altered level of consciousness, which is an acute and often reversible condition.
Option D: Crohn's disease is a chronic inflammatory bowel disease (IBD) that primarily affects the digestive system. It has no direct causal link to neurodegenerative dementia.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Etiology of Dementia as background academic context rather than a clinical decision trigger.
A key nursing role is to differentiate between dementia, delirium, and depression, as they can present with similar symptoms but require different management. A thorough history and assessment are crucial.
For patients with dementia, nurses focus on safety, managing behavioral symptoms, supporting activities of daily living (ADLs), and providing education and support to the family/caregivers.
What if the patient presented with a sudden onset of confusion over two days? In that case, the priority would be to investigate for delirium by checking for infections (like a UTI), metabolic imbalances (electrolytes, acid-base), and medication side effects, rather than assuming a new diagnosis of dementia.

How to Approach the Question

Identify the core concept of the question: It asks for the 'most common cause' of a specific medical condition (dementia).
This is a factual recall question. Access your knowledge about neurological disorders.
Evaluate each option. Alzheimer's disease is widely known as the primary cause of dementia.
Consider the other options. Recognize that acid-base and electrolyte imbalances cause acute, reversible conditions (delirium), not chronic dementia.
Eliminate Crohn's disease as it's an inflammatory bowel disease and unrelated to the brain in this context.
Confirm that Alzheimer's disease is the most frequent etiology among the choices.

Concept Tested & Keywords

QNukn8RWqD5JHtI9dFYqOq

E6 Kaplan Sadock's Synopsis of Psychiatry-2022 (pp 1-3768 of 3768) p. 777-779

E6 Medicine Harrison 22e Part 1 p. 235-237

Practise the full RUHS, Jaipur, PB B.Sc Nursing Entrance-2024

Attempt every question from this paper in a timed mock, then review the full solution for each one.