From Keath Low,
Your Guide to ADD / ADHD.
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The Basics

Attention deficit hyperactivity disorder (ADHD) is a biological, brain based condition that is characterized by poor attention and distractibility and/or hyperactive and impulsive behaviors. It is one of the most common mental disorders that develop in children. Symptoms can continue into adolescence and adulthood. If left untreated, ADHD can lead to poor school/work performance, poor social relationships and a general feeling of low self esteem.

Prevalence of ADHD

It is estimated that between 3 and 5 percent of preschool and school age children have ADHD or approximately two million children in the United States. This means in a class of 25 to 30 students, it is likely that at least one student will have this common condition.

ADHD begins in childhood, but it often lasts into adulthood. Studies estimate that 30-70 percent of children with ADHD will continue to have symptoms into adolescence and adulthood.

Causes

The exact cause of ADHD has not been determined, however the condition is thought to have a genetic and biological component. ADHD tends to occur among family members. Many research studies currently focus on identifying which genes, or combination of genes, may cause a person to be more susceptible to ADHD. Physical differences in parts of the brain are also thought to be linked to ADHD.

Risk Factors

Many studies have found that the greatest risk factor for ADHD is being male. Males are three times more likely to be diagnosed with ADHD as compared to females. Genetics and heredity are also major risk factors, as ADHD tends runs in families. Brain abnormalities or structural differences have also been found in individuals with ADHD.

Additional suspected risk factors include maternal use of cigarettes or alcohol during pregnancy which may affect brain development. Children who have been exposed to high levels of lead also may display ADHD symptoms.

ADD versus ADHD

Wondering about the differences between ADD and ADHD? ADD or attention deficit disorder is a general term frequently used to describe individuals that have attention deficit hyperactivity disorder without the hyperactive and impulsive behaviors. The terms are often used interchangeably for both those who do and those who do not have symptoms of hyperactivity and impulsiveness.

Related Reading:

The ADD Child vs the ADHD Child

What is it like to have ADHD?

Hyperfocus

_Sources:

American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition, Text Revision) DSM-IV Washington, D.C. 2000.

Barkley PhD, Russell A. Attention Deficit Hyperactivity Disorders: A Handbook for Diagnosis and Treatment. New York: Guildford Press. 1998.

Center for Disease Control and Prevention. “Prevalence of Diagnosis and Medication Treatment for Attention-Deficit Hyperactivity Disorder: United States, 2003.” Morbidity and Mortality Weekly Report, Mental Health in the United States. 54(34);842-847. 02 Sept. 2005.

National Institute of Mental Health. Attention Deficit Hyperactivity Disorder. Department of Health and Human Services. National Institutes of Health. 2006.