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Dive into the research topics where John T. Walkup is active.

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Featured researches published by John T. Walkup.


Neurorx | 2006

Contemporary Assessment and Pharmacotherapy of Tourette Syndrome

Lawrence Scahill; Gerald Erenberg; Cheston M. Berlin; Cathy L. Budman; Barbara J. Coffey; Joseph Jankovic; Louise Kiessling; Robert A. King; Roger Kurlan; Anthony E. Lang; Jonathan W. Mink; Tanya Murphy; Samual Zinner; John T. Walkup

SummaryTo develop a guide to clinical assessment and pharmacotherapy for children and adults with Tourette syndrome (TS), we reviewed published literature over the past 25 years to identify original articles and reviews on the assessment and pharmacological treatment of Tourette syndrome, attention—deficit/hyperactivity disorder (ADHD) and obsessive—compulsive disorder (OCD). The literature search also included a survey of reviews published in book chapters. The assessment section was compiled from several reviews. Pharmacological treatments were classified into those with strong empirical support (as evidenced by two positive placebo-controlled studies for tics, OCD, or ADHD in TS samples); modest empirical support (one positive placebo-controlled study), or minimal support (open-label data only). We conclude that accurate diagnosis, including identification of comorbid conditions, is an essential step toward appropriate treatment for patients with TS. In many patients with TS, symptom management requires pharmacotherapy for tics or coexisting conditions. The evidence supporting efficacy and safety for medications used in patients with TS varies. But this evidence offers the best guide to clinical practice.


Biological Psychiatry | 2001

The familial phenotype of obsessive-compulsive disorder in relation to tic disorders: the Hopkins OCD family study

Marco A. Grados; Mark A. Riddle; Jack Samuels; Kung Yee Liang; Rudolf Hoehn-Saric; O. Joseph Bienvenu; John T. Walkup; DongHo Song; Gerald Nestadt

BACKGROUND Obsessive-compulsive disorder (OCD) and tic disorders have phenomenological and familial-genetic overlaps. An OCD family study sample that excludes Tourettes syndrome in probands is used to examine whether tic disorders are part of the familial phenotype of OCD. METHODS Eighty case and 73 control probands and their first-degree relatives were examined by experienced clinicians using the Schedule for Affective Disorders and Schizophrenia-Lifetime Anxiety version. DSM-IV psychiatric diagnoses were ascertained by a best-estimate consensus procedure. The prevalence and severity of tic disorders, age-at-onset of OCD symptoms, and transmission of OCD and tic disorders by characteristics and type of proband (OCD + tic disorder, OCD - tic disorder) were examined in relatives. RESULTS Case probands and case relatives had a greater lifetime prevalence of tic disorders compared to control subjects. Tic disorders spanning a wide severity range were seen in case relatives; only mild severity was seen in control relatives. Younger age-at-onset of OCD symptoms and possibly male gender in case probands were associated with increased tic disorders in relatives. Although relatives of OCD + tic disorder and OCD - tic disorder probands had similar prevalences of tic disorders, this result is not conclusive. CONCLUSIONS Tic disorders constitute an alternate expression of the familial OCD phenotype.


American Journal of Medical Genetics | 2003

Obsessive-compulsive symptom dimensions in affected sibling pairs diagnosed with Gilles de la Tourette syndrome.

James F. Leckman; David L. Pauls; Heping Zhang; Maria Conceição do Rosario-Campos; Liliya Katsovich; Kenneth K. Kidd; Andrew J. Pakstis; John P. Alsobrook; Mary M. Robertson; William M. McMahon; John T. Walkup; Ben J.M. van de Wetering; Robert A. King; Donald J. Cohen

Obsessive‐compulsive disorder (OCD) is an etiologically heterogeneous disorder. Recent factor analyses have consistently identified several symptom dimensions, two of which are associated with increased familial risk for OCD; aggressive, sexual, and religious obsessions and checking compulsions (FACTOR 1) and symmetry and ordering obsessions and compulsions (FACTOR 2). Both of these symptom dimensions are also frequently seen in association with Gilles de la Tourette syndrome (GTS). The purpose of this study was to determine whether these obsessive‐compulsive (OC) symptom dimensions are correlated within families (between sibs and between parent‐child pairs). Using data collected by the Tourette Syndrome Association International Consortium for Genetics Affected Sibling Pair Study, the authors selected all available GTS sib pairs and their parents for which these OC symptom dimensions (factor scores) could be generated. This group included 128 full sibs and their mothers (54) and fathers (54). Four OC symptom dimension scores were computed for each family member using an algorithm derived from item endorsements from the Yale‐Brown Obsessive‐Compulsive Scale (Y‐BOCS) symptom checklist. In addition to a series of univariate analyses, complex segregation analyses were also completed using these quantitative OC symptom dimension scores. FACTOR 1 and FACTOR 2 scores were significantly correlated in sib pairs concordant for GTS. The mother–child correlations, but not father–child correlations, were also significant for these two factors. Segregation analyses were consistent with dominant major gene effects for both FACTOR 1 and FACTOR 2. We conclude that familial factors contribute significantly to OC symptom dimension phenotypes in GTS families. This familial contribution could be genetic or environmental.


Journal of the American Academy of Child and Adolescent Psychiatry | 2009

The Treatment of Adolescent Suicide Attempters Study (TASA): Predictors of Suicidal Events in an Open Treatment Trial

David A. Brent; Laurence L. Greenhill; Scott N. Compton; Graham J. Emslie; Karen C. Wells; John T. Walkup; Benedetto Vitiello; Oscar G. Bukstein; Barbara Stanley; Kelly Posner; Betsy Kennard; Mary F. Cwik; Ann Wagner; Barbara J. Coffey; John S. March; Mark A. Riddle; Tina R. Goldstein; John F. Curry; Shannon Barnett; Lisa Capasso; Jamie Zelazny; Jennifer L. Hughes; S. A. Shen; S. Sonia Gugga; J. Blake Turner

OBJECTIVE To identify the predictors of suicidal events and attempts in adolescent suicide attempters with depression treated in an open treatment trial. METHOD Adolescents who had made a recent suicide attempt and had unipolar depression (n =124) were either randomized (n = 22) or given a choice (n = 102) among three conditions. Two participants withdrew before treatment assignment. The remaining 124 youths received a specialized psychotherapy for suicide attempting adolescents (n = 17), a medication algorithm (n = 14), or the combination (n = 93). The participants were followed up 6 months after intake with respect to rate, timing, and predictors of a suicidal event (attempt or acute suicidal ideation necessitating emergency referral). RESULTS The morbid risks of suicidal events and attempts on 6-month follow-up were 0.19 and 0.12, respectively, with a median time to event of 44 days. Higher self-rated depression, suicidal ideation, family income, greater number of previous suicide attempts, lower maximum lethality of previous attempt, history of sexual abuse, and lower family cohesion predicted the occurrence, and earlier time to event, with similar findings for the outcome of attempts. A slower decline in suicidal ideation was associated with the occurrence of a suicidal event. CONCLUSIONS In this open trial, the 6-month morbid risks for suicidal events and for reattempts were lower than those in other comparable samples, suggesting that this intervention should be studied further. Important treatment targets include suicidal ideation, family cohesion, and sequelae of previous abuse. Because 40% of events occurred with 4 weeks of intake, an emphasis on safety planning and increased therapeutic contact early in treatment may be warranted.


Journal of the American Academy of Child and Adolescent Psychiatry | 1992

The Validity of Instruments Measuring Tic Severity in Tourette's Syndrome

John T. Walkup; Leon A. Rosenberg; Janice Brown; Harvey S. Singer

By using four different scales that measure tic severity in Tourettes syndrome, three independent judges concurrently evaluated their validity and interjudge reliability in 20 affected individuals. The Yale Global Tic Severity Scale, Tourettes Syndrome Severity Scale, Tourettes Syndrome-Clinical Global Impression Scale, and the Hopkins Motor and Vocal Tic Scale were equally effective in determining overall severity and showed good interrater reliability. Both historical information and direct observation of the subject were shown to have a significant contribution towards the overall assessment of tic severity. With all instruments, tic symptom ratings were shown to be independent of those for either attention-deficit hyperactivity disorder or obsessive-compulsive disorder. A 67% incidence of behavioral problems and social difficulties was identified by the Child Behavior Checklist. Nevertheless, associations with tic severity were limited to areas showing interference with social relationships and school adjustments. These results extend the understanding of Tourettes syndrome severity scales and provide additional information necessary for the development of a unified rating scale.


Brain & Development | 2003

Genetics of obsessive-compulsive disorders : new findings and challenges

Marco A. Grados; John T. Walkup; Samuel Walford

A review of the current state of research in the genetics of obsessive-compulsive disorder (OCD) is presented. OCD is a neuropsychiatric condition that affects 1-2% of the population and often has an early age at onset of symptoms. OCD has been shown to be familial, and a major gene effect has been reported. However, phenotypic and genetic heterogeneity of OCD poses multiple challenges for locating susceptibility genes. Strategies such as the use of phenotypic subtyping (using tic disorders or other anxiety disorders) and endophenotyping based on brain mechanisms underlying OCD (functional brain imaging and neuropsychological measures) may open ways to understand the genetic components of OCD. Using child probands and extended families for linkage an association studies is another venue to obtain greater informative families for genetic studies. A better understanding of environmental triggers, OCD subtypes and OCD pathophysiology will lead to locating genes that confer risk to OCD.


Journal of Child Neurology | 2006

Co-occurring psychiatric disorders in children and adolescents with tourette syndrome

Catherine Gaze; Hayden O. Kepley; John T. Walkup

More than half of all children and adolescents with Tourette syndrome show evidence of psychiatric comorbidity, exhibiting symptoms of attention-deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder, and other anxiety and mood disorders. Although the prevalence of co-occurring conditions varies depending on the clinical setting, it is crucial for clinicians to be familiar with these disorders because they are often more impairing than tics and can influence the initial treatment choice. Left untreated, these conditions can negatively affect important developmental outcomes, such as academic and social functioning. We review the most common co-occurring disorders, the relationship of these co-occurring disorders to Tourette syndrome, and treatment recommendations for co-occurring conditions when tic symptoms are present. (J Child Neurol 2006;21:657—664; DOI 10.2310/7010.2006.00170).


Neurochemistry International | 2008

Alterations in kynurenine precursor and product levels in schizophrenia and bipolar disorder

Christine L. Miller; Ida C. Llenos; Mary F. Cwik; John T. Walkup; Serge Weis

Increased concentrations of kynurenine pathway metabolites have been reported by several groups for disorders involving psychosis, including schizophrenia and bipolar disorder. To identify components of the pathway that may be relevant as biomarkers or may underlie the etiology of psychosis, it is essential to characterize the extent of kynurenine pathway activation and to investigate known regulators of one of the key kynurenine-producing enzymes, tryptophan 2,3-dioxygenase (TDO2), previously shown in this laboratory to be increased commensurate with kynurenine in postmortem anterior cingulate brain tissue from individuals with schizophrenia. Using this same anterior cingulate sample set from individuals with schizophrenia, bipolar disorder, depression and controls (N=12-14 per group), we measured the precursor of kynurenine and two downstream products. The precursor, tryptophan, was significantly increased only in the schizophrenia group (1.54-fold the mean control value, p=0.02), and through substrate-induced activation, may be one cause of the increased kynurenine and kynurenine metabolites. This finding for tryptophan differs from some, but not all, previous reports and methodological reasons for the discrepancies are discussed. A product of kynurenine metabolism, 3-OH-anthranilic acid was also significantly increased only in the schizophrenia group (1.68-fold the mean control value, p=0.03). 3-OH-anthranilic acid is a reactive species with cytotoxic properties, although the threshold for such effects is not known for neurons. Analysis of major pre- and post-mortem variables showed that none were confounding for these between-group experimental comparisons. Nicotinamide, a pathway end product, did not differ between groups but was associated with cause of death (suicide) within the bipolar group (p=0.03).


Pediatric Neurology | 2000

Infection: a stimulus for tic disorders

Harvey S. Singer; Joseph D Giuliano; Aphrodite M Zimmerman; John T. Walkup

The object of this study was to investigate the potential association of infections, especially group A hemolytic streptococcal infection, with the abrupt onset/exacerbation of tics or obsessive-compulsive behaviors. A structured clinical interview was used to evaluate 80 consecutive children, 5-17 years of age, with a diagnosis of tic disorder. Forty-two patients (53%) described a sudden, explosive onset or worsening of tic symptoms; 15 of these 42 had their exacerbation historically associated with an infection, nine of the 15 specifically with a streptococcal infection. Comparisons between those nine individuals and the remainder of the study population are presented. The results of this study reveal that descriptions of an abrupt tic onset or exacerbation are not uncommon in children with tic disorders; approximately 11% of children with tic disorders described abrupt changes of tic behavior within a 6-week period after a streptococcal infection.


Pediatric Drugs | 2009

Pediatric Generalized Anxiety Disorder Epidemiology, Diagnosis, and Management

Courtney P. Keeton; Amie C. Kolos; John T. Walkup

Pediatric generalized anxiety disorder (GAD) is characterized by excessive and uncontrollable worry about a variety of events and is accompanied by physical symptoms such as headaches, tension, restlessness, gastrointestinal distress, and heart palpitations. Symptoms impose marked distress and interfere with social, emotional, and educational functioning. GAD occurs in over 10% of children and adolescents, has an average age of onset of 8.5 years, and is more often reported in girls. Common co-occurring conditions include separation anxiety disorder and social phobia.Assessment involves a multi-informant, multi-method approach involving the child, parents, and school teachers. A clinical interview should be conducted to assess for the three primary ways anxiety presents: behaviors, thoughts, and somatic symptoms. Several semi-structured diagnostic interviews are available, and the Anxiety Disorders Interview Schedule is increasingly used. Rating scales completed by the patient, caregivers, and teachers provide useful information for diagnosis and symptom monitoring. Several scales are available to assess patients for the Diagnostic and Statistical Manual of Mental Disorders (4th Edition) GAD diagnosis; however, instruments generally cannot distinguish children with GAD from children with similar anxiety disorders.Both cognitive-behavioral therapy (CBT) and selective serotonin reuptake inhibitors (SSRIs) have demonstrated efficacy for the treatment of pediatric anxiety disorders including GAD. Evidence suggests that the combination of CBT plus sertraline offers additional benefit compared with either treatment alone. With pharmacotherapy, systematic tracking of treatment-emergent adverse events such as headaches, stomach aches, behavioral activation, worsening symptoms, and emerging suicidal thoughts is important. Recommended starting doses are fluvoxamine 25mg/day, fluoxetine 10mg/day, and sertraline 25mg/day, though lower starting doses are possible. Dosing can be adjusted as often as weekly with the goal of achieving a high-quality response, while minimizing side effects. Long-term treatment with medication has not been well studied; however, to achieve optimal long-term outcome extended use of medication may be required. It is recommended to continue medication for approximately 1 year following remission in symptoms, and when discontinuing medication to choose a stress-free time of the year. If symptoms return, medication re-initiation should be considered seriously.

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Benedetto Vitiello

National Institutes of Health

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Lawrence Scahill

University Hospitals of Cleveland

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Christopher J. Kratochvil

University of Nebraska Medical Center

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