Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by persistent inattention, hyperactivity, and impulsivity. It affects approximately 5-8% of children globally, with around 60-70% of cases persisting into adulthood. ADHD has significant implications for educational attainment, social interactions, and occupational success.

Diagnostic Criteria and Symptoms

To diagnose ADHD, symptoms must manifest before age 12 and be evident across multiple settings. Core features include inattention (difficulty sustaining focus, disorganization, and forgetfulness), hyperactivity (excessive movement and inability to remain still), and impulsivity (hasty actions without forethought). These behaviors disrupt academic and social functioning. For instance, children with ADHD may struggle to complete schoolwork, disrupt classroom settings, and face rejection from peers due to impulsive or socially intrusive behavior.

Adults diagnosed with ADHD must show evidence that symptoms were present before age 12, even if not formally diagnosed in childhood. This is confirmed through self-reports, family interviews, or school records. Diagnosis often occurs when lifelong symptoms become more noticeable due to adult responsibilities.

Long-Term Implications

ADHD is associated with numerous adverse life outcomes. Studies have found that untreated individuals diagnosed in childhood often experience lower educational attainment, higher unemployment rates, poorer social functioning, and increased risk of substance abuse. ADHD also correlates with impulsive decision-making, which contributes to higher rates of traffic accidents and legal troubles.

Causes and Risk Factors

Risk factors for ADHD include premature birth, low birth weight, prenatal exposure to alcohol, smoking, lead, and certain pesticides, particularly in combination with poverty or genetic susceptibility. Adverse childhood events, such as abuse or neglect, further increase the likelihood of ADHD. Genetic factors account for up to 70% of ADHD variance, involving multiple genes linked to dopamine and serotonin regulation, which also overlap with other psychological disorders. The delayed maturation hypothesis suggests slower brain development in individuals with ADHD, particularly in the prefrontal cortex, leading to reduced cortical thickness and weaker neural connections. These neurobiological differences contribute to deficits in executive functioning, working memory, emotion regulation, and reward processing. Dysregulation of dopamine, acetylcholine, and melatonin further impacts reward motivation and impulse control, underlying many ADHD symptoms.

Environmental factors, such as prenatal nicotine exposure, premature birth, and childhood adversity, further elevate the risk. Contrary to earlier beliefs, evidence does not support sugar or poor parenting as causative factors.

Treatment and Management

Treatment options for ADHD often include behavioral therapy, educational support, and medications like methylphenidate (Ritalin) or amphetamine salts (Adderall), which enhance dopamine activity. Early intervention and consistent treatment significantly improve outcomes, reducing the likelihood of academic failure, social isolation, and substance use disorders.

Research continues to refine understanding and treatment strategies, offering hope for better management and improved quality of life for those affected by ADHD.