Introduction: Attention Deficit/Hyperactivity Disorder (ADHD) is one of the most frequently diagnosed psychiatric disorders of childhood. It occurs approximately in 3-9% of school age children. Despite the fact that it also occurs in adults, ADHD represents a barely known and rarely recognized disorder in practice. The objective of this article is to provide a detailed review of epidemiological research into ADHD in adults.
Methods: Our research group conducted a systematic review of the epidemiologic literature on adult ADHD based on the Medline and Psychlit databases and papers that have been published during the past 10 years (search was conducted on the following key words: "adult", "adhd", "prevalence" "epidemiology".
Results: Findings from follow-up studies indicate that the persistence of symptoms of ADHD in adulthood is in the range of 4-66%. Of the population studies that are presented, one estimated the cumulative incidence between 5 and 19 years of age; the lower and upper limits of the estimates were 7.5% and 16%, respectively. Four population studies were concerned with prevalence in the general population; thus, providing the most reliable estimates for adult ADHD. These studies indicated that, depending on the diagnostic criteria employed, the prevalence of ADHD ranged between 1 and 4.7%.
Conclusion: In view of the above epidemiological data and of the fact that most studies dealing with adult ADHD have indicated a close link between the symptoms of ADHD and severe difficulties in social adaptation (including the ability to work, functional problems related to criminal behaviour, and psychiatric comorbidity), research into adult ADHD in Hungary, improvement of its diagnosis and recognition, and its adequate treatment is of prime importance from the perspective of clinical practice.