Dementia

Home » Dementia » Overview, Types, Incidence and Prevalence, Risk Factors

Overview

Dementia refers to a loss of cognitive function (cognition) due to changes in the brain caused by disease or trauma. The changes may occur gradually or quickly; and how they occur may determine whether dementia is reversible or irreversible.

Cognition is the act or process of thinking, perceiving, and learning. Cognitive functions that may be affected by dementia include the following:

• Decision making, judgment
• Memory
• Spatial orientation
• Thinking, reasoning
• Verbal communication

Dementia also may result in behavioral and personality changes, depending on the area(s) of the brain affected.

Types

Some dementia is reversible and can be cured partially or completely with treatment. The degree of reversibility often depends on how quickly the underlying cause is treated.

Irreversible dementia is caused by an incurable condition (e.g., Alzheimer's disease). Patients with irreversible dementia are eventually unable to care for themselves and may require round-the-clock care.

Incidence and Prevalence
An estimated 2 million people in the United States suffer from severe dementia and another 1 to 5 million people experience mild to moderate dementia. Five to eight percent of people over the age of 65 have some form of dementia and the number doubles every 5 years over age 65.

The prevalence of dementia has increased over the past few decades, either because of greater awareness and more accurate diagnosis, or because increased longevity is creating a larger population of elderly, which is the age group most commonly affected.

Risk Factors

The greatest risk factor for dementia is advanced age. Inheriting the genes associated with Alzheimer's or Huntington's disease is a risk factor. Untreated infectious and metabolic disease and substance abuse also can lead to dementia.

Other risk factors include the following:

• Brain tumor
• Cardiovascular disease (e.g., hypertension, atherosclerosis)
• Head injury
• Kidney failure, liver disease, thyroid disease
• Vitamin deficiencies: B12, folic acid, B1 (thiamine)

Dementia Resources

	Join Our Dementia Forum Do you have a question, want to share medical advice, or just need to discuss your situation with someone else having a similar experience? The healthchannels forum is a resource for everyone to share and discuss their health and medical needs with others.	Advertising Disclaimer
	Living with...Share your story Do you have a personal health story that you would like to share with others? As a source of free patient education, our goal is to provide our users with trustworthy information and support from others. That's why we've started our "Living with..." sections.
	Our "Living With..." support pages are a place to share experiences about living with a certain condition, disease, disorder, or illness and for loved ones of those dealing with health-related issues. Many people, especially when newly diagnosed, find comfort in knowing that others are having a similar experience. Help others by sharing your story. View stories already submitted. June 1st is National Cancer Survivors Day Share your survival story and help others in the fight against cancer. Read cancer survivor stories already submitted.
	Stay Updated Sign up for our newsletter and receive important updates on the medical conditions that are most important to you.
Advertising Disclaimer To quickly access health information from your website's browser, download Healthcommunities.com's healthchannels toolbar. Advertising Disclaimer