Trastorno por déficit de atención e hiperactividad y trastorno bipolar pediátrico: ¿Comorbilidad o traslape clínico? Una Revisión. Parte.

Attention deficit hyperactivity disorder (ADHD) can present itself with a wide variety of comorbid psychiatric entities and can easily be misdiagnosed with disorders such as the pediatric bipolar disorder (PedBP), making early detection and treatment difficult. The main objective of this review is to evaluate the relationship between PedBP and ADHD. Several studies have addressed this association, establishing a high rate of comorbidity, from 57% to 93%. The risk of developing PedBP in ADHD population has also been studied, documenting a ten-fold increase risk in both genders compared with age-matched healthy controls. Pediatric bipolar disorder is still a diagnostic entity which is hard to recognize and differentiate from other disorders, even with the current international diagnostic criteria. Individuals with ADHD with a current depressive episode, suicide attempts and/or substance abuse and that carry a family load (mainly parents) for bipolar disorder are at increased risk of actually having this disorder. Several researchers have compared clinical symptoms expressed in children with ADHD and PedBP. They have found that children with PebBP exhibit higher frequency of elated mood, increased energy, thought disorder, flight of ideas, increased speed in speech and irritability than those with ADHD. Other authors report higher rates of thought disorders, anxiety, depression, aggression and delinquent behavior amongst children with PedBP than those with ADHD. It has also been reported that children with PedBP compared to those with ADHD present higher rates of euphoria, grandiosity, racing thoughts and decreased need for sleep. Yet another study found that euphoria and increased energy distinguished youths with PedBP from those with other psychiatric disorders, and found that with the group of depressed patients exhibit higher rates of suicidal thoughts and behavior than other diagnostic groups. Some cues to diagnose and differentiate PedBP and ADHD have been proposed: ADHD symptoms appearing suddenly or later in life, loss of therapeutic response to stimulants in a previous responder, intermittent symptoms, emergence of elated mood and decreased need for sleep, severe mood shifting, hallucinations or thought disorders, family history of bipolar disorder and lack of response to adequate treatment. Three of the seven criteria for bipolar disorder are shared with ADHD (distractibility, increased goal directed activity and talkativeness), making the clinical distinction between ADHD and early onset PedBP a difficult task. In fact, most children diagnosed with PedBP present symptoms and behavior compatible with a simultaneous ADHD. The role of ADHD as a prodromic, phenocopy, comorbid condition and/or as a misdiagnosis for PedBP can be further clarified by: 1. case follow-up to determine if comorbid diagnosis can predict the course or determine a prognosis factor; and 2. family genetic studies which are convenient for the evaluation of complex comorbid conditions. Some studies have suggested that this comorbid syndrome may possess a specific genotype, as well a particular course, a pattern of treatment response and may represent a distinctive clinical condition. High comorbidity BPD, both in adult and child and adolescent populations, runs a similar pattern to that of other important diagnostic categories in child and adolescent psychiatry. From a clinical perspective, these findings support the notion of avoiding hierarchical diagnoses. Furthermore, it questions the vision of categorical entities as it is proposed in the current diagnostic classification (ICD and DSM). Currently, when we talk about ADHD, we cannot separate it from other disruptive behavior disorders, such as conduct disorder (CD) and oppositional-defiant disorder (ODD). Epidemiological studies show that 40% to 70% of children with ADHD have CD or ODD, and some of them also present comorbid internalizing disorders.… [ABSTRACT FROM AUTHOR]