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Treatment decisions based on scalar and functional baseline covariates

Ciarleglio, Adam; Petkova, Eva; Ogden, R Todd; Tarpey, Thaddeus
The amount and complexity of patient-level data being collected in randomized-controlled trials offer both opportunities and challenges for developing personalized rules for assigning treatment for a given disease or ailment. For example, trials examining treatments for major depressive disorder are not only collecting typical baseline data such as age, gender, or scores on various tests, but also data that measure the structure and function of the brain such as images from magnetic resonance imaging (MRI), functional MRI (fMRI), or electroencephalography (EEG). These latter types of data have an inherent structure and may be considered as functional data. We propose an approach that uses baseline covariates, both scalars and functions, to aid in the selection of an optimal treatment. In addition to providing information on which treatment should be selected for a new patient, the estimated regime has the potential to provide insight into the relationship between treatment response and the set of baseline covariates. Our approach can be viewed as an extension of "advantage learning" to include both scalar and functional covariates. We describe our method and how to implement it using existing software. Empirical performance of our method is evaluated with simulated data in a variety of settings and also applied to data arising from a study of patients with major depressive disorder from whom baseline scalar covariates as well as functional data from EEG are available.
PMCID:4691227
PMID: 26111145
ISSN: 1541-0420
CID: 1875022

Biomarkers of cognitive decline in elderly depressives [Meeting Abstract]

Pomara, N; Bruno, D; Ciarleglio, A; Constantine, A; Reichert, C; Petkova, E; Zetterberg, H; Blennow, K
Background: Numerous studies have suggested that the APOE e4 allele, an established risk factor for AD, may act synergistically with depression to increase the risk for progressive cognitive decline and conversion to MCI/AD. However, these findings remain controversial and have been reported inconsistently. A possible reason for these conflicting results is differences in methodologies across studies, including differences in the definition of depression, failure to properly diagnose depression or AD, short duration of follow up, differences in age, and possible inclusion of individuals with preexisting cognitive decline or MCI. These considerations prompted us to conduct a 3-year longitudinal prospective study in cognitively intact elderly individuals, who either had a diagnosis of MDD or were healthy controls, to determine if e4 and depression interacted with respect to progressive cognitive decline. We focused primarily on neurobehavioral tests sensitive to early AD and also examined the CSF total tau/Ab42 ratio, which has been linked to incident MCI/AD-related decline. Methods: 91 participants were included in this study, 60 older and with an MMSE score of at least 28 at the beginning of the 3-year longitudinal investigation. 45 participants had a diagnosis of MDD. APOE status and CSF AD biomarkers were determined at baseline and participants underwent a comprehensive neuropsychological test battery that included the Buschke Selective Reminding Test and the Boston Naming Task. Regression models examining change scores from baseline to follow-up were employed to test our hypotheses. Results: Adjusting for age and MMSE score, elderly participants with depression and carrying APOE e4 showed greater decline on average in the Boston Naming Task (p < 0.01) and a trend with high imagery performance (p = 0.05). A higher CSF total tau/Ab42 ratio was associated with decline in memory performance among depressed subjects (r =-0.45, p = 0.03, n = 23), regardless of APOE status, but not in controls. Conclusions: Our results indicate that cognitively intact depressive e4 carriers have greater decline in selective cognitive tests especially in a confrontation naming task even during a relatively short three year longitudinal period compared to controls. Additionally, increased brain AD pathology as reflected by the CSF tau/Ab42 ratio appeared to be associated with greater decline in memory performance in all depressives, regardless of APOE e4 status
EMBASE:72133026
ISSN: 0893-133x
CID: 1923592

EXPLORING PERSONALITY DIAGNOSIS STABILITY FOLLOWING ACUTE PSYCHOTHERAPY FOR CHRONIC POSTTRAUMATIC STRESS DISORDER

Markowitz, John C; Petkova, Eva; Biyanova, Tatyana; Ding, Ke; Suh, Eun Jung; Neria, Yuval
BACKGROUND: Axis I comorbidity complicates diagnosing axis II personality disorders (PDs). PDs might influence Axis I outcome. No research has examined psychotherapy effects on PDs of treating Axis I comorbidity. Secondary analysis of a randomized controlled trial examined PD diagnostic stability after brief psychotherapy of chronic posttraumatic stress disorder (PTSD). METHODS: Patients with chronic PTSD were randomly assigned to 14 weeks of prolonged exposure, interpersonal psychotherapy, or relaxation therapy. Assessments included the Structured Clinical Interview for DSM-IV, Patient Version (SCID-P) and Structured Clinical Interview for DSM-IV Axis II Disorders (SCID-II) at baseline, week 14, and for treatment responders (>/=30% clinician-administered PTSD scale improvement, defined a priori) at week 26 follow-up. We hypothesized patients whose PTSD improved would retain fewer baseline PD diagnoses posttreatment, particularly with personality traits PTSD mimics, e.g. paranoid and avoidant. RESULTS: Forty-seven (47%) of 99 SCID-II patients evaluated at baseline received a SCID-II diagnosis: paranoid (28%), obsessive-compulsive (27%), and avoidant (23%) PDs were most prevalent. Among 78 patients who repeated SCID-II evaluations posttreatment, 45% (N = 35) had baseline PD diagnoses, of which 43% (N = 15/35) lost at week 14. Three (7%) patients without baseline PDs acquired diagnoses at week 14; 10 others shifted diagnoses. Treatment modality and PTSD response were unrelated to PD improvement. Of treatment responders reevaluated at follow-up (N = 44), 56% with any baseline Axis II diagnosis had none at week 26. CONCLUSION: This first evaluation of Axis I psychotherapy effects on personality disorder stability found that acutely treating a chronic state decreased apparent trait-across most PDs observed. These exploratory findings suggest personality diagnoses may have limited prognostic meaning in treating chronic PTSD.
PMCID:4674381
PMID: 26439430
ISSN: 1520-6394
CID: 2038172

Short-term test-retest reliability of resting state fMRI metrics in children with and without attention-deficit/hyperactivity disorder

Somandepalli, Krishna; Kelly, Clare; Reiss, Philip T; Zuo, Xi-Nian; Cameron Craddock, R; Yan, Chao-Gan; Petkova, Eva; Xavier Castellanos, F; Milham, Michael P; Di Martino, Adriana
To date, only one study has examined test-retest reliability of resting state fMRI (R-fMRI) in children, none in clinical developing groups. Here, we assessed short-term test-retest reliability in a sample of 46 children (11-17.9 years) with attention-deficit/hyperactivity disorder (ADHD) and 57 typically developing children (TDC). Our primary test-retest reliability measure was the intraclass correlation coefficient (ICC), quantified for a range of R-fMRI metrics. We aimed to (1) survey reliability within and across diagnostic groups, and (2) compare voxel-wise ICC between groups. We found moderate-to-high ICC across all children and within groups, with higher-order functional networks showing greater ICC. Nearly all R-fMRI metrics exhibited significantly higher ICC in TDC than in children with ADHD for one or more regions. In particular, posterior cingulate and ventral precuneus exhibited group differences in ICC across multiple measures. In the context of overall moderate-to-high test-retest reliability in children, regional differences in ICC related to diagnostic groups likely reflect the underlying pathophysiology for ADHD. Our currently limited understanding of the factors contributing to inter- and intra-subject variability in ADHD underscores the need for large initiatives aimed at examining their impact on test-retest reliability in both clinical and developing populations.
PMID: 26365788
ISSN: 1878-9307
CID: 1779102

Expression profile analysis of hippocampal CA1 pyramidal neurons in aged Ts65Dn mice, a model of Down syndrome (DS) and Alzheimer's disease (AD)

Alldred, Melissa J; Lee, Sang Han; Petkova, Eva; Ginsberg, Stephen D
Down syndrome (DS) is caused by the triplication of human chromosome 21 (HSA21) and is the most common genetic cause of intellectual disability, with individuals having deficits in cognitive function including hippocampal learning and memory and neurodegeneration of cholinergic basal forebrain neurons, a pathological hallmark of Alzheimer's disease (AD). To date, the molecular underpinnings driving this pathology have not been elucidated. The Ts65Dn mouse is a segmental trisomy model of DS and like DS/AD pathology, displays age-related cognitive dysfunction and basal forebrain cholinergic neuron (BFCN) degeneration. To determine molecular and cellular changes important for elucidating mechanisms of neurodegeneration in DS/AD pathology, expression profiling studies were performed. Molecular fingerprinting of homogeneous populations of Cornu Ammonis 1 (CA1) pyramidal neurons was performed via laser capture microdissection followed by Terminal Continuation RNA amplification combined with custom-designed microarray analysis and subsequent validation of individual transcripts by qPCR and protein analysis via immunoblotting. Significant alterations were observed within CA1 pyramidal neurons of aged Ts65Dn mice compared to normal disomic (2N) littermates, notably in excitatory and inhibitory neurotransmission receptor families and neurotrophins, including brain-derived neurotrophic factor as well as several cognate neurotrophin receptors. Examining gene and protein expression levels after the onset of BFCN degeneration elucidated transcriptional and translational changes in neurons within a vulnerable circuit that may cause the AD-like pathology seen in DS as these individuals age, and provide rational targets for therapeutic interventions.
PMCID:4297601
PMID: 25031177
ISSN: 1863-2653
CID: 1071192

A comparison of hippocampal volume and integrity: Which is the better predictor of cognitive decline? [Meeting Abstract]

Bruno, D; Ciarleglio, A; Grothe, M J; Nierenberg, J; Bachman, A; Teipel, S J; Petkova, E; Sidtis, J; Adrenkani, B; Pomara, N
Background: Volumetric analyses of MRI data have been employed to predict conversion to Alzheimer's disease (AD), and individuals with preclinical AD tend to show atrophy in the right medial temporal lobe, which includes the hippocampus. In this study, we set out to compare a volumetric measurement of the hippocampus to a newly developed measure of hippocampal integrity in their respective potential for prediction of generalized cognitive performance (MMSE) over time. Methods: Ninety participants, who were cognitively intact at baseline and aged 60 or older, were recruited for a study on major depressive disorder (MDD) and tested twice, over three years. Linear regression models were applied to the data with the change in MMSE score as outcome, and hippocampal integrity (HI), hippocampal volume (HV), age and MDD status among the predictors. HI was measured for the left and right hippocampi as the ratio of the parenchymal voxels to the total number of voxels in an automatically determined hippocampus ROI. The ROI was determined by local affine registration of 65 previously delineated hippocampus atlases to the test subject. HVs were extracted from MRI images using an automated volumetric approach. Results: Change in MMSE performance was significantly predicted by both integrity and volume: greater HI and HV values were associated with less decline. However, when comparing predictors' contributions to the models, HI was slightly better than HV for the right side, and explained more of the variance in MMSE performance; HI and HV contributions were largely comparable for the left side. Conclusions: More research is needed to evaluate whether hippocampal integrity or hippocampal volume is a more accurate predictor of cognitive decline, but tentative results from this study appear to suggest that right side HI measures have the potential to be sensitive to future changes in general cognitive ability
EMBASE:72125347
ISSN: 1552-5260
CID: 1924872

Predictors of cognitive decline in elderly depressives [Meeting Abstract]

Pomara, N; Bruno, D; Ciarleglio, A; Constantine, A; Reichert, C; Zetterberg, H; Blennow, K; Petkova, E; Sidtis, J
Background: The APOE e4 allele, an established risk factor for AD, may act synergistically with depression to increase the risk for progressive cognitive decline and conversion to MCI/AD. However, these findings have been reported inconsistently. Methodological differences across studies, including in the definition of depression, failure to properly diagnose depression or AD, short duration of follow up, and possible inclusion of individuals with preexisting cognitive decline or MCI. These considerations prompted us to conduct a 3-year longitudinal prospective study in cognitively intact elderly individuals, who either had a diagnosis of MDD or were healthy controls, to determine if e4 and depression interacted with respect to progressive cognitive decline. We focused primarily on neurobehavioral tests sensitive to early AD and also examined the CSF total tau/Abeta42 ratio, which has been linked to incident MCI/AD-related decline. Methods: 91 participants were included in this study, age 60 and older, with an MMSE 28 at the beginning of the 3- year longitudinal investigation. 45 participants had a diagnosis of MDD. Participants underwent a comprehensive neuropsychological test battery that included the Buschke Selective Reminding Test and Boston Naming Task at baseline and annually thereafter. APOE status on all and CSFAD biomarkers on a subset of subjects were determined at baseline. Regression analyses examining neuropsych change scores (baseline to follow-up) as functions of baseline characteristics. Results: Adjusting for age and MMSE score, participants with depression and carrying. Conclusions: Our results indicate that cognitively intact depressive e4 carriers have greater decline in selective cognitive tests especially in a confrontation naming task even during a relatively short three year longitudinal period compared to controls. Additionally, increased brain AD pathology as reflected by the CSF tau/Abeta42 ratio appeared to be associated with greater decline in memory performance in all depressives, regardless of APOE e4 status
EMBASE:72124686
ISSN: 1552-5260
CID: 1924912

Is Exposure Necessary? A Randomized Clinical Trial of Interpersonal Psychotherapy for PTSD

Markowitz, John C; Petkova, Eva; Neria, Yuval; Van Meter, Page E; Zhao, Yihong; Hembree, Elizabeth; Lovell, Karina; Biyanova, Tatyana; Marshall, Randall D
Objective: Exposure to trauma reminders has been considered imperative in psychotherapy for posttraumatic stress disorder (PTSD). The authors tested interpersonal psychotherapy (IPT), which has demonstrated antidepressant efficacy and shown promise in pilot PTSD research as a non-exposure-based non-cognitive-behavioral PTSD treatment. Method: The authors conducted a randomized 14-week trial comparing IPT, prolonged exposure (an exposure-based exemplar), and relaxation therapy (an active control psychotherapy) in 110 unmedicated patients who had chronic PTSD and a score >50 on the Clinician-Administered PTSD Scale (CAPS). Randomization stratified for comorbid major depression. The authors hypothesized that IPT would be no more than minimally inferior (a difference <12.5 points in CAPS score) to prolonged exposure. Results: All therapies had large within-group effect sizes (d values, 1.32-1.88). Rates of response, defined as an improvement of >30% in CAPS score, were 63% for IPT, 47% for prolonged exposure, and 38% for relaxation therapy (not significantly different between groups). CAPS outcomes for IPT and prolonged exposure differed by 5.5 points (not significant), and the null hypothesis of more than minimal IPT inferiority was rejected (p=0.035). Patients with comorbid major depression were nine times more likely than nondepressed patients to drop out of prolonged exposure therapy. IPT and prolonged exposure improved quality of life and social functioning more than relaxation therapy. Conclusions: This study demonstrated noninferiority of individual IPT for PTSD compared with the gold-standard treatment. IPT had (nonsignificantly) lower attrition and higher response rates than prolonged exposure. Contrary to widespread clinical belief, PTSD treatment may not require cognitive-behavioral exposure to trauma reminders. Moreover, patients with comorbid major depression may fare better with IPT than with prolonged exposure.
PMCID:4464805
PMID: 25677355
ISSN: 0002-953x
CID: 1461892

D-serine for the treatment of negative symptoms in individuals at clinical high risk of schizophrenia: a pilot, double-blind, placebo-controlled, randomised parallel group mechanistic proof-of-concept trial

Kantrowitz, Joshua T; Woods, Scott W; Petkova, Eva; Cornblatt, Barbara; Corcoran, Cheryl M; Chen, Huaihou; Silipo, Gail; Javitt, Daniel C
BACKGROUND: Antagonists of N-methyl-D-aspartate-type glutamate receptors (NMDAR) induce symptoms that closely resemble those of schizophrenia, including negative symptoms. D-serine is a naturally occurring NMDAR modulator that reverses the effects of NMDAR antagonists in animal models of schizophrenia. D-serine effects have been assessed previously for treatment of established schizophrenia, but not in the early stages of the disorder. We aimed to assess effects of D-serine on negative symptoms in at risk individuals. METHODS: We did a double-blind, placebo-controlled, parallel-group randomised clinical trial at four academic US centres. Individuals were eligible for inclusion in the study if they were at clinical high risk of schizophrenia, aged between 13-35 years, had a total score of more than 20 on the Scale of Prodromal Symptoms (SOPS), and had an interest in participation in the clinical trial. Exclusion criteria included a history of suprathreshold psychosis symptoms (ie, no longer qualifying as prodromal) or clinical judgment that the reported symptoms from the SOPS were accounted for better by another disorder (eg, depression). Randomisation was done using a generated list with block sizes of four. Participants were stratified by site, with participants, investigators, and assessors all masked through use of identical looking placebos and centralised drug dispensation to study assignment. D-serine (60 mg/kg) was given orally in divided daily doses for 16 weeks. The primary endpoint was for negative SOPS, measured weekly for the first 6 weeks, then every 2 weeks. Participants who received at least one post-baseline assessment were included in analysis. Serum cytokine concentrations were collected at baseline, midpoint, and endpoint to assess the mechanism of action. Safety outcomes including laboratory assessments were obtained for all individuals. This trial is registered with ClinicalTrials.gov, number NCT0082620. FINDINGS: We enrolled participants between April 2, 2009, and July 23, 2012. 44 participants were randomly assigned to receive either D-serine (n=20) or placebo (n=24); 35 had assessable data (15 D-serine, 20 placebo). D-serine induced a 35.7% (SD 17.8) improvement in negative symptoms, which was significant compared with placebo (mean final SOPS negative score 7.6 [SEM 1.4] for D-serine group vs 11.3 [1.2] for placebo group; d=0.68, p=0.03). Five participants who received D-serine and nine participants who received placebo discontinued the study early because of withdrawn consent or loss to follow-up (n=8), conversion to psychosis (n=2), laboratory-confirmed adverse events (n=2), or protocol deviations (n=2). INTERPRETATION: This study supports use of NMDAR-based interventions, such as D-serine, for treatment of prodromal symptoms of schizophrenia. On the basis of observed effect sizes, future studies with sample sizes of about 40 per treatment group would be needed for confirmation of beneficial effects on symptoms and NMDAR-related inflammatory changes. Long-term studies are needed to assess effects on psychosis conversion in individuals at clinical high risk of schizophrenia. FUNDING: National Institutes of Health.
PMID: 26360284
ISSN: 2215-0366
CID: 1772672

Reduction of beta-amyloid and gamma-secretase by calorie restriction in female Tg2576 mice

Schafer, Marissa J; Alldred, Melissa J; Lee, Sang Han; Calhoun, Michael E; Petkova, Eva; Mathews, Paul M; Ginsberg, Stephen D
Research indicates that female risk of developing Alzheimer's disease (AD) is greater than that of males. Moderate reduction of calorie intake, known as calorie restriction (CR), reduces pathology in AD mouse models and is a potentially translatable prevention measure for individuals at-risk for AD, as well as an important tool for understanding how the brain endogenously attenuates age-related pathology. Whether sex influences the response to CR remains unknown. In this study, we assessed the effect of CR on beta-amyloid peptide (Abeta) pathology and hippocampal CA1 neuron specific gene expression in the Tg2576 mouse model of cerebral amyloidosis. Relative to ad libitum (AL) feeding, CR feeding significantly reduced hippocampal Abeta burden in 15-month-old female, but not age-matched male, Tg2576 mice. Sustained CR also significantly reduced expression of presenilin enhancer 2 (Psenen) and presenilin 1, components of the gamma-secretase complex, in Tg2576 females. These results indicate that long-term CR significantly reduces age-dependent female Tg2576 Abeta pathology, which is likely to involve CR-mediated reductions in gamma-secretase-dependent amyloid precursor protein (APP) metabolism.
PMCID:4346433
PMID: 25556162
ISSN: 0197-4580
CID: 1420202