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BackgroundAttention Deficit Hyperactivity disorder (ADHD) is one of the most common and challenging childhood neurobehavioral disorders. ADHD is known to negatively impact children, their families, and their community. About one-third to one-half of patients with ADHD will have persistent symptoms into adulthood. The prevalence in the United States is estimated at 5–11%, representing 6.4 million children nationwide. The variability in the prevalence of ADHD worldwide and within the US may be due to the wide range of factors that affect accurate assessment of children and youth. Because of these obstacles to assessment, ADHD is under-diagnosed, misdiagnosed, and undertreated.ObjectivesWe examined factors associated with making and receiving the diagnosis of ADHD. We sought to review the consequences of a lack of diagnosis and treatment for ADHD on children’s and adolescent’s lives and how their families and the community may be involved in these consequences.MethodsWe reviewed scientific articles looking for factors that impact the identification and diagnosis of ADHD and articles that demonstrate naturalistic outcomes of diagnosis and treatment. The data bases PubMed and Google scholar were searched from the year 1995 to 2015 using the search terms “ADHD, diagnosis, outcomes.” We then reviewed abstracts and reference lists within those articles to rule out or rule in these or other articles.ResultsMultiple factors have significant impact in the identification and diagnosis of ADHD including parents, healthcare providers, teachers, and aspects of the environment. Only a few studies detailed the impact of not diagnosing ADHD, with unclear consequences independent of treatment. A more significant number of studies have examined the impact of untreated ADHD. The experience around receiving a diagnosis described by individuals with ADHD provides some additional insights.ConclusionADHD diagnosis is influenced by perceptions of many different members of a child’s community. A lack of clear understanding of ADHD and the importance of its diagnosis and treatment still exists among many members of the community including parents, teachers, and healthcare providers. More basic and clinical research will improve methods of diagnosis and information dissemination. Even before further advancements in science, strong partnerships between clinicians and patients with ADHD may be the best way to reduce the negative impacts of this disorder.

Summary Prenatal stress has been widely demonstrated to have links with behavioral problems in clinical populations and animal models, however, few investigations have examined the immediate developmental events that are affected by prenatal stress. Here, we utilize GAD67GFP transgenic mice in which GABAergic progenitors express green fluorescent protein (GFP) to examine the impact of prenatal stress on the development of these precursors to inhibitory neurons. Pregnant female mice were exposed to restraint stress three times daily from embryonic day 12 (E12) onwards. Their offspring demonstrated changes in the distribution of GFP-positive (GFP+) GABAergic progenitors in the telencephalon as early as E13 and persisting until postnatal day 0. Changes in distribution reflected alterations in tangential migration and radial integration of GFP+ cells into the developing cortical plate. Fate mapping of GAD67GFP+progenitors with bromodeoxyuridine injected at E13 demonstrated a significant increase of these cells at P0 in anterior white matter. An overall decrease in GAD67GFP+ progenitors at P0 in medial frontal cortex could not be attributed to a reduction in cell proliferation. Significant changes in dlx2, nkx2.1 and their downstream target erbb4, transcription factors which regulate interneuron migration, were found within the prenatally-stressed developing forebrain, while no differences were seen in mash1, a determinant of interneuron fate, bdnf, a maturation factor for GABAergic cells or fgf2, an early growth/differentiation factor. These results demonstrate that early disruption in GABAergic progenitor migration caused by prenatal stress may be responsible for neuronal defects in disorders with GABAergic abnormalities like schizophrenia.

Prenatal stress exposure is associated with adverse psychiatric outcomes, including autism and ADHD, as well as locomotor and social inhibition and anxiety-like behaviors in animal offspring. Similarly, maternal immune activation also contributes to psychiatric risk and aberrant offspring behavior. The mechanisms underlying these outcomes are not clear. Offspring microglia and the pro-inflammatory cytokine interleukin-6 (IL-6), known to influence microglia, may serve as common mechanisms between prenatal stress and prenatal immune activation. To evaluate the role of prenatal IL-6 in prenatal stress, microglia morphological analyses were conducted at embryonic days 14 (E14), E15, and in adult mice. Offspring microglia and behavior were evaluated after repetitive maternal restraint stress, repetitive maternal IL-6, or maternal IL-6 blockade during stress from E12 onwards. At E14, novel changes in cortical plate embryonic microglia were documented—a greater density of the mutivacuolated morphology. This resulted from either prenatal stress or IL-6 exposure and was prevented by IL-6 blockade during prenatal stress. Prenatal stress also resulted in increased microglia ramification in adult brain, as has been previously shown. As with embryonic microglia, prenatal IL-6 recapitulated prenatal stress-induced changes in adult microglia. Furthermore, prenatal IL-6 was able to recapitulate the delay in GABAergic progenitor migration caused by prenatal stress. However, IL-6 mechanisms were not necessary for this delay which persisted after prenatal stress despite IL-6 blockade. As we have previously demonstrated, behavioral effects of prenatal stress in offspring, including increased anxiety-like behavior, decreased sociability, and locomotor inhibition, may be related to these GABAergic delays. While adult microglia changes were ameliorated by IL-6 blockade, these behavioral changes were independent of IL-6 mechanisms, similar to GABAergic delays. This and previous work from our laboratory suggest multiple mechanisms, including GABAergic delays, may underlie prenatal stress-linked deficits.