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175


Input permutation method to detect active voxels in fMRI study

Lee, Sang H; Lim, Johan; Park, Dohwan; Biswal, Bharat B; Petkova, Eva
Correctly identifying voxels or regions of interest (ROI) that actively respond to a given stimulus is often an important objective/step in many functional magnetic resonance imaging (fMRI) studies. In this article, we study a nonparametric method to detect active voxels, which makes minimal assumption about the distribution of blood oxygen level-dependent (BOLD) signals. Our proposal has several interesting features. It uses time lagged correlation to take into account the delay in response to the stimulus, due to hemodynamic variations. We introduce an input permutation method (IPM), a type of block permutation method, to approximate the null distribution of the test statistic. Also, we propose to pool the permutation-derived statistics of preselected voxels for a better approximation to the null distribution. Finally, we control multiple testing error rate using the local false discovery rate (FDR) by Efron [Correlation and large-scale simultaneous hypothesis testing. J Am Stat Assoc 102 (2007) 93-103] and Park et al. [Estimation of empirical null using a mixture of normals and its use in local false discovery rate. Comput Stat Data Anal 55 (2011) 2421-2432] to select the active voxels.
PMCID:3678281
PMID: 22819177
ISSN: 0730-725x
CID: 197622

Order test for high-dimensional two-sample means

Lee, Sang H.; Lim, Johan; Li, Erning; Vannucci, Marina; Petkova, Eva
ISI:000304722200020
ISSN: 0378-3758
CID: 169695

AN EXAMINATION OF THE INFLUENCE OF A SEQUENTIAL TREATMENT ON THE COURSE AND IMPACT OF DISSOCIATION AMONG WOMEN WITH PTSD RELATED TO CHILDHOOD ABUSE

Cloitre, Marylene; Petkova, Eva; Wang, Jing; Lu Lassell, Feihan
BACKGROUND: It has been proposed that posttraumatic stress disorder (PTSD) patients who experience significant dissociation upon exposure to traumatic reminders may do less well in trauma-focused therapies. We explored whether a sequenced two-component treatment in which an emotion regulation skills training module preceding exposure would improve outcomes for those with significant dissociation. METHODS: Analyses were conducted on data from an RCT in which 104 women with PTSD related to childhood abuse were assigned to one of three treatment conditions: Skills Training in Affective and Interpersonal Regulation (STAIR) followed by Narrative Story Telling (NST; STAIR/NST), STAIR followed by supportive counseling (SC; STAIR/SC), or SC followed by NST (SC/NST). RESULTS: Baseline dissociation was associated with differential outcome such that at low levels of dissociation the three treatments were equally effective but at higher levels STAIR/NST resulted in greater reductions in dissociative symptoms. Level of baseline dissociation did not moderate the effect of the treatments on PTSD outcome. At all levels of baseline dissociation, STAIR/NST produced better PTSD outcome. At posttreatment, however, participants with high dissociation treated with STAIR/NST continued to improve during follow-up, those treated with STAIR/SC maintained gains, and those treated with SC/NST experienced loss of posttreatment PTSD symptom gains. CONCLUSIONS: The differential results observed among the treatments depending on severity of dissociation at baseline and at posttreatment suggest the potential clinical utility of identifying a dissociative subtype of PTSD and of the benefits of sequenced, phase-oriented treatment approaches.
PMID: 22550033
ISSN: 1091-4269
CID: 179229

A Double-Blind, Placebo-Controlled Trial of Omega-3 Fatty Acids in Tourette's Disorder

Gabbay, V; Babb, JS; Klein, RG; Panzer, AM; Katz, Y; Alonso, CM; Petkova, E; Wang, J; Coffey, BJ
OBJECTIVE:Clinical observations have suggested therapeutic effects for omega-3 fatty acids (O3FA) in Tourette's disorder (TD), but no randomized, controlled trials have been reported. In a placebo-controlled trial, we examined the efficacy of O3FA in children and adolescents with TD.METHODS:Thirty-three children and adolescents (ages 6-18) with TD were randomly assigned, double-blind, to O3FA or placebo for 20 weeks. O3FA consisted of combined eicosapentaenoic acid and docosahexaenoic acid. Placebo was olive oil. Groups were compared by using (1) intent-to-treat design, with the last-observation-carried-forward controlling for baseline measures and attention-deficit/hyperactivity disorder via (a) logistic regression, comparing percentage of responders on the primary Yale Global Tic Severity Scale (YGTSS)-Tic and secondary (YGTSS-Global and YGTSS-Impairment) outcome measures and (b) analysis of covariance; and (2) longitudinal mixed-effects models.RESULTS:At end point, subjects treated with O3FA did not have significantly higher response rates or lower mean scores on the YGTSS-Tic (53% vs 38%; 15.6 +/- 1.6 vs 17.1 +/- 1.6, P > .1). However, significantly more subjects on O3FA were considered responders on the YGTSS-Global measure (53% vs 31%, P = .05) and YGTSS-Impairment measure (59% vs 25%, P < .05), and mean YGTSS-Global scores were significantly lower in the O3FA-treated group than in the placebo group (31.7 +/- 2.9 vs 40.9 +/- 3.0, P = .04). Obsessive-compulsive, anxiety, and depressive symptoms were not significantly affected by O3FA. Longitudinal analysis did not yield group differences on any of the measures.CONCLUSIONS:O3FA did not reduce tic scores, but it may be beneficial in reduction of tic-related impairment for some children and adolescents with TD. Limitations include the small sample and the possible therapeutic effects of olive oil.
PMCID:3362909
PMID: 22585765
ISSN: 0031-4005
CID: 167144

Lower CSF amyloid beta peptides and higher F2-isoprostanes in cognitively intact elderly individuals with major depressive disorder

Pomara, Nunzio; Bruno, Davide; Sarreal, Antero S; Hernando, Raymundo T; Nierenberg, Jay; Petkova, Eva; Sidtis, John J; Wisniewski, Thomas M; Mehta, Pankaj D; Pratico, Domenico; Zetterberg, Henrik; Blennow, Kaj
OBJECTIVE: Major depressive disorder is common in the elderly, and symptoms are often not responsive to conventional antidepressant treatment, especially in the long term. Soluble oligomeric and aggregated forms of amyloid beta peptides, especially amyloid beta 42, impair neuronal and synaptic function. Amyloid beta 42 is the main component of plaques and is implicated in Alzheimer's disease. Amyloid beta peptides also induce a depressive state in rodents and disrupt major neurotransmitter systems linked to depression. The authors assessed whether major depression was associated with CSF levels of amyloid beta, tau protein, and F2-isoprostanes in elderly individuals with major depressive disorder and age-matched nondepressed comparison subjects. METHOD: CSF was obtained from 47 cognitively intact volunteers (major depression group, N=28; comparison group, N=19) and analyzed for levels of soluble amyloid beta, total and phosphorylated tau proteins, and isoprostanes. RESULTS: Amyloid beta 42 levels were significantly lower in the major depression group relative to the comparison group, and amyloid beta 40 levels were lower but only approaching statistical significance. In contrast, isoprostane levels were higher in the major depression group. No differences were observed in total and phosphorylated tau proteins across conditions. Antidepressant use was not associated with differences in amyloid beta 42 levels. CONCLUSIONS: Reduction in CSF levels of amyloid beta 42 may be related to increased brain amyloid beta plaques or decreased soluble amyloid beta production in elderly individuals with major depression relative to nondepressed comparison subjects. These results may have implications for our understanding of the pathophysiology of major depression and for the development of treatment strategies.
PMCID:3586557
PMID: 22764362
ISSN: 0002-953x
CID: 174136

A Multisite Study of the Clinical Diagnosis of Different Autism Spectrum Disorders

Lord C; Petkova E; Hus V; Gan W; Lu F; Martin DM; Ousley O; Guy L; Bernier R; Gerdts J; Algermissen M; Whitaker A; Sutcliffe JS; Warren Z; Klin A; Saulnier C; Hanson E; Hundley R; Piggot J; Fombonne E; Steiman M; Miles J; Kanne SM; Goin-Kochel RP; Peters SU; Cook EH; Guter S; Tjernagel J; Green-Snyder LA; Bishop S; Esler A; Gotham K; Luyster R; Miller F; Olson J; Richler J; Risi S
CONTEXT: Best-estimate clinical diagnoses of specific autism spectrum disorders (autistic disorder, pervasive developmental disorder-not otherwise specified, and Asperger syndrome) have been used as the diagnostic gold standard, even when information from standardized instruments is available. OBJECTIVE: To determine whether the relationships between behavioral phenotypes and clinical diagnoses of different autism spectrum disorders vary across 12 university-based sites. DESIGN: Multisite observational study collecting clinical phenotype data (diagnostic, developmental, and demographic) for genetic research. Classification trees were used to identify characteristics that predicted diagnosis across and within sites. SETTING: Participants were recruited through 12 university-based autism service providers into a genetic study of autism. PARTICIPANTS: A total of 2102 probands (1814 male probands) between 4 and 18 years of age (mean [SD] age, 8.93 [3.5] years) who met autism spectrum criteria on the Autism Diagnostic Interview-Revised and the Autism Diagnostic Observation Schedule and who had a clinical diagnosis of an autism spectrum disorder. Main Outcome Measure Best-estimate clinical diagnoses predicted by standardized scores from diagnostic, cognitive, and behavioral measures. RESULTS: Although distributions of scores on standardized measures were similar across sites, significant site differences emerged in best-estimate clinical diagnoses of specific autism spectrum disorders. Relationships between clinical diagnoses and standardized scores, particularly verbal IQ, language level, and core diagnostic features, varied across sites in weighting of information and cutoffs. CONCLUSIONS: Clinical distinctions among categorical diagnostic subtypes of autism spectrum disorders were not reliable even across sites with well-documented fidelity using standardized diagnostic instruments. Results support the move from existing subgroupings of autism spectrum disorders to dimensional descriptions of core features of social affect and fixated, repetitive behaviors, together with characteristics such as language level and cognitive function
PMCID:3626112
PMID: 22065253
ISSN: 1538-3636
CID: 142976

Early Childhood Family Intervention and Long-term Obesity Prevention Among High-risk Minority Youth

Brotman, Laurie Miller; Dawson-McClure, Spring; Huang, Keng-Yen; Theise, Rachelle; Kamboukos, Dimitra; Wang, Jing; Petkova, Eva; Ogedegbe, Gbenga
OBJECTIVES: To test the hypothesis that family intervention to promote effective parenting in early childhood affects obesity in preadolescence. METHODS: Participants were 186 minority youth at risk for behavior problems who enrolled in long-term follow-up studies after random assignment to family intervention or control condition at age 4. Follow-up Study 1 included 40 girls at familial risk for behavior problems; Follow-up Study 2 included 146 boys and girls at risk for behavior problems based on teacher ratings. Family intervention aimed to promote effective parenting and prevent behavior problems during early childhood; it did not focus on physical health. BMI and health behaviors were measured an average of 5 years after intervention in Study 1 and 3 years after intervention in Study 2. RESULTS: Youth randomized to intervention had significantly lower BMI at follow-up relative to controls (Study 1 P = .05; Study 2 P = .006). Clinical impact is evidenced by lower rates of obesity (BMI >/=95th percentile) among intervention girls and boys relative to controls (Study 2: 24% vs 54%, P = .002). There were significant intervention-control group differences on physical and sedentary activity, blood pressure, and diet. CONCLUSIONS: Two long-term follow-up studies of randomized trials show that relative to controls, youth at risk for behavior problems who received family intervention at age 4 had lower BMI and improved health behaviors as they approached adolescence. Efforts to promote effective parenting and prevent behavior problems early in life may contribute to the reduction of obesity and health disparities.
PMCID:3289522
PMID: 22311988
ISSN: 0031-4005
CID: 159839

Asthma Self-Management is Sub-Optimal in Urban Hispanic and African American/Black Early Adolescents with Uncontrolled Persistent Asthma

Bruzzese, Jean-Marie; Stepney, Cesalie; Fiorino, Elizabeth K; Bornstein, Lea; Wang, Jing; Petkova, Eva; Evans, David
Introduction. Youth as young as 11 are given responsibility to manage their asthma. Yet, little is known regarding early adolescents' asthma self-management behaviors. This study characterizes urban early adolescents' asthma self-management behaviors and perceived responsibility to manage asthma, exploring demographic differences and examining the relationship between asthma responsibility and disease management. Methods. About 317 Hispanic and African American/Black early adolescents (mean age = 12.71) with persistent, uncontrolled asthma reported prevention and symptom management steps, and responsibility for asthma care. We used Poisson, cumulative logistic, logistic, and linear mixed-effects regression models to assess the relationships among demographic predictors, prevention and management behaviors, and responsibility for asthma care. Results. Fifty percent took 7-9 prevention steps; few saw physicians when asymptomatic or took daily medication. When symptomatic, 92% used medication to treat symptoms and 56% sought medical attention. Controlling for asthma responsibility, fewer older youth reported observing how they feel when asthma is likely to start, observing symptom changes, or asking for help. More boys reported taking medication daily or upon trigger exposure. Controlling for age, gender, and race/ethnicity, those reporting more asthma responsibility were less likely to report taking management steps, seeking preventive care, asking for help, or going to a doctor/hospital for their asthma. Conclusions. Early adolescents' asthma self-management is suboptimal. With increasing age, they are less observant regarding their asthma and less likely to seek help. Although they perceive themselves to have greater responsibility for managing their asthma, early adolescents do less to care for their asthma, suggesting they are being given responsibility for asthma care prematurely
PMCID:4515962
PMID: 22149141
ISSN: 1532-4303
CID: 149803

Low frequency oscillations of response time explain parent ratings of inattention and hyperactivity/impulsivity

Mairena, Maria Angeles; Di Martino, Adriana; Dominguez-Martin, Cristina; Gomez-Guerrero, Lorena; Gioia, Gerard; Petkova, Eva; Castellanos, F Xavier
Greater intra-subject variability (ISV) in response time is a heritable endophenotype of attention-deficit/hyperactivity disorder (ADHD). Spontaneous low frequency oscillations (LFO: 0.01-0.1 Hz) observed in brain functional magnetic resonance signals might account for such behavioral variability. Recently, we demonstrated that ISV in response time (RT) explained ratings of ADHD symptoms. Building on this finding, here we hypothesized that LFO in RT time series would explain these ratings, both independently and in addition to RT coefficient of variation (CV). To measure RT LFO, we applied Morlet wavelet transform to the previously collected RT data. Our community sample consisted of 98 children (including 66 boys, mean age 9.9 +/- 1.4 years), who completed four computer Tasks of Executive Control. Conners' Parent Rating Scale ratings were obtained. RT LFO of three tasks significantly explained ratings of inattention, hyperactivity and three global Conners' subscales. In addition, RT LFO during two tasks that included an inhibitory component increased the proportions of variance explained in subscales of both inattention and hyperactivity/impulsivity, beyond the effects of RT-CV. Three specific low frequency bands (Slow-5: 0.01-0.027 Hz; Slow-4: 0.027-0.073 Hz; Slow-3: 0.073-0.20 Hz) were strongly related to the ADHD scales. We conclude that RT LFO predict dimensional ratings of ADHD symptoms both independently and in addition to RTCV. Results suggest that frequency analyses are a suitable methodology to link behavioral responses to putative underlying physiological processes.
PMCID:3821733
PMID: 22287035
ISSN: 1018-8827
CID: 161183

The NKI-Rockland Sample: A Model for Accelerating the Pace of Discovery Science in Psychiatry

Nooner, Kate Brody; Colcombe, Stanley J; Tobe, Russell H; Mennes, Maarten; Benedict, Melissa M; Moreno, Alexis L; Panek, Laura J; Brown, Shaquanna; Zavitz, Stephen T; Li, Qingyang; Sikka, Sharad; Gutman, David; Bangaru, Saroja; Schlachter, Rochelle Tziona; Kamiel, Stephanie M; Anwar, Ayesha R; Hinz, Caitlin M; Kaplan, Michelle S; Rachlin, Anna B; Adelsberg, Samantha; Cheung, Brian; Khanuja, Ranjit; Yan, Chaogan; Craddock, Cameron C; Calhoun, Vincent; Courtney, William; King, Margaret; Wood, Dylan; Cox, Christine L; Kelly, A M Clare; Di Martino, Adriana; Petkova, Eva; Reiss, Philip T; Duan, Nancy; Thomsen, Dawn; Biswal, Bharat; Coffey, Barbara; Hoptman, Matthew J; Javitt, Daniel C; Pomara, Nunzio; Sidtis, John J; Koplewicz, Harold S; Castellanos, Francisco Xavier; Leventhal, Bennett L; Milham, Michael P
The National Institute of Mental Health strategic plan for advancing psychiatric neuroscience calls for an acceleration of discovery and the delineation of developmental trajectories for risk and resilience across the lifespan. To attain these objectives, sufficiently powered datasets with broad and deep phenotypic characterization, state-of-the-art neuroimaging, and genetic samples must be generated and made openly available to the scientific community. The enhanced Nathan Kline Institute-Rockland Sample (NKI-RS) is a response to this need. NKI-RS is an ongoing, institutionally centered endeavor aimed at creating a large-scale (N > 1000), deeply phenotyped, community-ascertained, lifespan sample (ages 6-85 years old) with advanced neuroimaging and genetics. These data will be publically shared, openly, and prospectively (i.e., on a weekly basis). Herein, we describe the conceptual basis of the NKI-RS, including study design, sampling considerations, and steps to synchronize phenotypic and neuroimaging assessment. Additionally, we describe our process for sharing the data with the scientific community while protecting participant confidentiality, maintaining an adequate database, and certifying data integrity. The pilot phase of the NKI-RS, including challenges in recruiting, characterizing, imaging, and sharing data, is discussed while also explaining how this experience informed the final design of the enhanced NKI-RS. It is our hope that familiarity with the conceptual underpinnings of the enhanced NKI-RS will facilitate harmonization with future data collection efforts aimed at advancing psychiatric neuroscience and nosology.
PMCID:3472598
PMID: 23087608
ISSN: 1662-453x
CID: 422642