Common questions about Attention deficit hyperactivity disorder

Short answers, pulled from the story.

What is the heritability rate of attention deficit hyperactivity disorder?

Attention deficit hyperactivity disorder has a heritability rate of 74 percent, meaning that 74 percent of the presence of the disorder in the population is due to genetic factors. The remaining 20 to 30 percent of variance is mediated by de-novo mutations and non-shared environmental factors that provide for or produce brain injuries. Environmental risks are not related to social or familial factors but exert their effects very early in life, in the prenatal or early postnatal period.

Which brain structures show volume reduction in attention deficit hyperactivity disorder?

Individuals with attention deficit hyperactivity disorder show a general reduction of volume in certain brain structures, with a proportionally greater decrease in the volume in the left-sided prefrontal cortex. The posterior parietal cortex also shows thinning, and subcortical volumes of the accumbens, amygdala, caudate, hippocampus, and putamen appear smaller compared with controls. Functional MRI studies have shown evidence for a higher connectivity between subcortical and cortical regions, such as between the caudate and prefrontal cortex.

How many adults worldwide have persistent attention deficit hyperactivity disorder?

Worldwide, it is estimated that 2.58 percent of adults have persistent attention deficit hyperactivity disorder, where the individual currently meets the criteria and there is evidence of childhood onset. In 2020, this represented 139.84 million adults, while 6.76 percent of adults have symptomatic attention deficit hyperactivity disorder, meaning that they currently meet the criteria regardless of childhood onset. Around 15 percent of children with attention deficit hyperactivity disorder continue to meet full DSM-IV-TR criteria at 25 years of age.

What are the diagnostic criteria for attention deficit hyperactivity disorder according to the DSM-5?

According to the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, symptoms must be present for six months or more to a degree that is much greater than others of the same age. Those under 17 require at least six symptoms of either inattention or hyperactivity/impulsivity, while those 17 years or older require at least five symptoms. The symptoms must be present in at least two settings and must directly interfere with or reduce quality of functioning, and several symptoms must have been present before age 12.

Which digital therapeutic was approved by the FDA for attention deficit hyperactivity disorder in 2020?

Akili Interactive Labs's video game-based digital therapeutic AKL-T01, marketed as EndeavourRx, became the first game-based therapeutic granted marketing authorization by the FDA for any type of condition in 2020. A pediatric STARS-ADHD randomized, double-blind, parallel-group, controlled trial demonstrated that AKL-T01 significantly improved performance on the Test of Variables of Attention compared to a control group after four weeks of at-home use. A 2023 study in the Journal of the American Academy of Child & Adolescent Psychiatry investigated the efficacy and safety of AKL-T01 in adults with attention deficit hyperactivity disorder.

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