Douglas E. Williamson

Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime version (K-SADS-PL) : Initial reliability and validity data

OBJECTIVE To describe the psychometric properties of the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime version (K-SADS-PL) interview, which surveys additional disorders not assessed in prior K-SADS, contains improved probes and anchor points, includes diagnosis-specific impairment ratings, generates DSM-III-R and DSM-IV diagnoses, and divides symptoms surveyed into a screening interview and five diagnostic supplements. METHOD Subjects were 55 psychiatric outpatients and 11 normal controls (aged 7 through 17 years). Both parents and children were used as informants. Concurrent validity of the screen criteria and the K-SADS-PL diagnoses was assessed against standard self-report scales. Interrater (n = 15) and test-retest (n = 20) reliability data were also collected (mean retest interval: 18 days; range: 2 to 36 days). RESULTS Rating scale data support the concurrent validity of screens and K-SADS-PL diagnoses. Interrater agreement in scoring screens and diagnoses was high (range: 93% to 100%). Test-retest reliability kappa coefficients were in the excellent range for present and/or lifetime diagnoses of major depression, any bipolar, generalized anxiety, conduct, and oppositional defiant disorder (.77 to 1.00) and in the good range for present diagnoses of posttraumatic stress disorder and attention-deficit hyperactivity disorder (.63 to .67). CONCLUSION Results suggest the K-SADS-PL generates reliable and valid child psychiatric diagnoses.

Childhood and Adolescent Depression: A Review of the Past 10 Years. Part II

OBJECTIVE To qualitatively review the literature of the past decade covering the epidemiology, clinical characteristics, natural course, biology, and other correlates of early-onset major depressive disorder (MDD) and dysthymic disorder (DD). METHOD A computerized search for articles published during the past 10 years was made and selected studies are presented. RESULTS Early-onset MDD and DD are frequent, recurrent, and familial disorders that tend to continue into adulthood, and they are frequently accompanied by other psychiatric disorders. These disorders are usually associated with poor psychosocial and academic outcome and increased risk for substance abuse, bipolar disorder, and suicide. In addition, DD increases the risk for MDD. There is a secular increase in the prevalence of MDD, and it appears that MDD is occurring at an earlier age in successive cohorts. Several genetic, familial, demographic, psychosocial, cognitive, and biological correlates of onset and course of early-onset depression have been identified. Few studies, however, have examined the combined effects of these correlates. CONCLUSIONS Considerable advances have been made in our knowledge of early-onset depression. Nevertheless, further research is needed in understanding the pathogenesis of childhood mood disorders. Toward this end, studies aimed at elucidating mechanisms and interrelationships among the different domains of risk factors are needed.

Preference for Immediate over Delayed Rewards Is Associated with Magnitude of Ventral Striatal Activity

Discounting future outcomes as a function of their deferred availability underlies much of human decision making. Discounting, or preference for immediate over delayed rewards of larger value, is often associated with impulsivity and is a risk factor for addictive disorders such as pathological gambling, cigarette smoking, and drug and alcohol abuse. The ventral striatum (VS) is involved in mediating behavioral responses and physiological states associated with reward, and dysregulation of the VS contributes to addiction, perhaps by affecting impulsive decision-making. Behavioral tests of delay discounting (DD), which index preference for smaller immediate over larger delayed rewards, covary with impulsive tendencies in humans. In the current study, we examined the relationship between individual differences in DD, measured in a behavioral assessment, and VS activity measured with blood oxygenation level-dependent functional magnetic resonance imaging, in 45 adult volunteers. VS activity was determined using a task involving positive and negative feedback with monetary reward. Analyses revealed that individual differences in DD correlate positively with magnitude of VS activation in response to both positive and negative feedback, compared with a no-feedback control condition. Variability in DD was also associated with differential VS activation in response to positive, compared with negative, feedback. Collectively, our results suggest that increased preference for smaller immediate over larger delayed rewards reflects both a relatively indiscriminate and hyper-reactive VS circuitry. They also highlight a specific neurocognitive mechanism that may contribute to increased risk for addiction.

A pilot study of amygdala volumes in pediatric generalized anxiety disorder

BACKGROUND The neurodevelopment of childhood anxiety disorders is not well understood. Basic research has implicated the amygdala and circuits related to these nuclei as being central to several aspects of fear and fear-related behaviors in animals. METHODS Magnetic resonance imaging was used to measure amygdala volumes and comparison brain regions in 12 child and adolescent subjects with generalized anxiety disorder and 24 comparison subjects. Groups were matched on age, sex, height, and handedness and were also similar on measures of weight, socioeconomic status, and full scale IQ. RESULTS Right and total amygdala volumes were significantly larger in generalized anxiety disorder subjects. Intracranial, cerebral, cerebral gray and white matter, temporal lobe, hippocampal, and basal ganglia volumes and measures of the midsagittal area of the corpus callosum did not differ between groups. CONCLUSIONS Although these data are preliminary and from a small sample, the results are consistent with a line of thinking that alterations in the structure and function of the amygdala may be associated with pediatric generalized anxiety disorder.

The Psychosocial Functioning and Family Environment of Depressed Adolescents

OBJECTIVE This study examined measures of functional impairment and family relations in a sample of 62 adolescents with major depressive disorder (MDD) and 38 normal controls with no history of psychiatric illness. METHOD Ratings of the following domains were obtained: mother-child relations, father-child relations, spousal relations, sibling relations, peer relations, and school performance. Ratings of each domain for the 3-month period preceding the assessment were derived from information obtained using a semistructured interview administered independently to the adolescents and one of their parents. RESULTS Adolescents with MDD were found to have severe difficulties in all areas. Ninety percent of the depressed adolescents had scores greater than 2 SD above the mean of the normal controls on one or more of the domain ratings. In addition, adolescents with difficulties in parent-child relations were more likely than those adolescents without problems in family relations to have difficulties in peer relations and school performance. CONCLUSIONS The authors discuss the importance of systematically examining psychosocial variables in future studies of the etiology, course, and treatment of MDD in adolescents.

A regulatory variant of the human tryptophan hydroxylase-2 gene biases amygdala reactivity

Recent studies have indicated that a newly identified second isoform of the tryptophan hydroxylase gene (TPH2) is preferentially involved in the rate-limiting synthesis of neuronal serotonin. Genetic variation in the human TPH2 gene (hTPH2) has been associated with altered in vitro enzyme activity as well as increased risk for mood disorders. Here, we provide the first in vivo evidence that a relatively frequent regulatory variant (G(−844)T) of hTPH2 biases the reactivity of the amygdala, a neural structure critical in the generation and regulation of emotional behaviors.

Fractional anisotropy of water diffusion in cerebral white matter across the lifespan

Determining the time of peak of cerebral maturation is vital for our understanding of when cerebral maturation ceases and the cerebral degeneration in healthy aging begins. We carefully mapped changes in fractional anisotropy (FA) of water diffusion for eleven major cerebral white matter tracts in a large group (831) of healthy human subjects aged 11-90. FA is a neuroimaging index of micro-structural white matter integrity, sensitive to age-related changes in cerebral myelin levels, measured using diffusion tensor imaging. The average FA values of cerebral white matter (WM) reached peak at the age 32 ± 6 years. FA measurements for all but one major cortical white matter tract (cortico-spinal) reached peaks between 23 and 39 years of age. The maturation rates, prior to age-of-peak were significantly correlated (r=0.74; p=0.01) with the rates of decline, past age-of-peak. Regional analysis of corpus callosum (CC) showed that thinly-myelinated, densely packed fibers in the genu, that connect pre-frontal areas, maturated later and showed higher decline in aging than the more thickly myelinated motor and sensory areas in the body and splenium of CC. Our findings can be summarized as: associative, cerebral WM tracts that reach their peak FA values later in life also show progressively higher age-related decline than earlier maturing motor and sensory tracts. These findings carry multiple and diverse implications for both theoretical studies of the neurobiology of maturation and aging and for the clinical studies of neuropsychiatric disorders.

Clinical Presentation and Course of Depression in Youth: Does Onset in Childhood Differ From Onset in Adolescence?

OBJECTIVE To simultaneously and prospectively compare the clinical presentation, course, and parental psychiatric history between children and adolescents with major depressive disorder. METHOD A group of prepubertal children (n = 46) and postpubertal adolescents (n = 22) were assessed with structured interviews for psychopathology and parental psychiatric history and followed once every 2 years for approximately 5 years. RESULTS With the exception of more depressive melancholic symptoms in the adolescents, both groups had similar depressive symptomatology, duration (average 17 months), severity of the index episode, rates of recovery (85%) and recurrence (40%), comorbid disorders, and parental psychiatric history. Female sex, increased guilt, prior episodes of depression, and parental psychopathology were associated with worse longitudinal course. CONCLUSIONS In general, major depressive disorder is manifested similarly in children and adolescents, and both groups have a protracted clinical course and high family loading for psychiatric disorders.

Parent-child bonding and family functioning in depressed children and children at high risk and low risk for future depression.

OBJECTIVE To evaluate parent-child bonding and familial functioning in depressed children, children at high risk for depression, and low-risk controls. METHOD Diagnoses of children and their relatives were obtained via structured interviews with all available informants. Depressed children (n = 54) received a diagnosis of current major depressive disorder (MDD). The high-risk children (n = 21) had no lifetime diagnoses of mood disorders, but at least one first-degree relative with a lifetime history of depression. The low-risk controls (n = 23) had no lifetime psychiatric disorders and no first-degree relative with a lifetime history of mood disorders. Parent-child bonding was evaluated with the childs report on the Parental Bonding Instrument (PBI). Familial functioning was evaluated with each parent answering the Family Assessment Device (FAD). RESULTS Significant differences were found between the MDD and low-risk children on most parameters of the PBI and FAD. The children with MDD reported significantly elevated maternal overprotection, and their fathers scored significantly lower on the FAD scales of Behavioral Control and General Functioning, compared with the high-risk children. Mothers of high-risk children had significantly lower scores on the Roles and Affective Involvement dimensions of the FAD compared with mothers of low-risk children. Current maternal depression had a deleterious effect on the childs perception of maternal protection and paternal care, mothers report on all FAD scales, and fathers report on most FAD scales, whether interacting with the childs depression or existing even if the child was not depressed. CONCLUSION Maternal depression and its interaction with the childs depression appear to have negative consequences for parent-child bonding and family functioning.

A Secular Increase in Child and Adolescent Onset Affective Disorder

Both longitudinal and cross-sectional studies utilizing population and family study samples have found evidence for a secular increase in major affective disorders in adults. Applying techniques used in cross-sectional studies in adults to family study data of children and adolescents, the authors demonstrate evidence of a parallel secular increase for child and adolescent onset affective disorders. Normal and depressed prepubertal probands were identified. All full siblings were directly interviewed for lifetime episodes of affective disorder. Analysis of the siblings (probands not further analyzed in this article) by the Cox proportional hazards model demonstrates that the risk for affective disorder is higher in siblings born more recently.