Factor structure and construct validity of the Behavioral Dyscontrol Scale-II

Language use predicts symptoms of fragile X-associated tremor/ataxia syndrome in men and women with the FMR1 premutation

Fragile X-associated tremor/ataxia syndrome (FXTAS) is an age-related neurodegenerative disorder caused by a premutation of the FMR1 gene on the X chromosome. Despite the pervasive physical and cognitive effects of FXTAS, no studies have examined language in symptomatic males and females, limiting utility as an outcome measure in clinical trials of FXTAS. The goal of this work is to determine (a) the extent to which male and female FMR1 premutation carriers with FXTAS symptoms differ in their language use and (b) whether language production predicts FXTAS symptoms. Thirty-one individuals with the FMR1 premutation (21M, 10F), ages 58-85 years with some symptoms of FXTAS, were recruited from a larger cross-sectional study. Participants completed a five-minute monologic language sample. Language transcripts were assessed for rate of dysfluencies, lexical-semantics, syntax, and speech rate. Multivariable linear and ordinal regressions were used to predict FXTAS-associated symptoms, cognitive functioning, and executive functioning. Males and females did not differ in their language use. Language production predicted FXTAS symptom severity, cognitive functioning, and executive functioning. Language production difficulties may co-occur with FXTAS-associated symptoms and may be a viable outcome measure in future clinical trials, with future research needed.

Activation Ratio Correlates with IQ in Female Carriers of the FMR1 Premutation

Carriers of the FMR1 premutation (PM) allele are at risk of one or more clinical conditions referred to as FX premutation-associated conditions (FXPAC). Since the FMR1 gene is on the X chromosome, the activation ratio (AR) may impact the risk, age of onset, progression, and severity of these conditions. The aim of this study was to evaluate the reliability of AR measured using different approaches and to investigate potential correlations with clinical outcomes. Molecular and clinical assessments were obtained for 30 PM female participants, and AR was assessed using both Southern blot analysis (AR-Sb) and methylation PCR (AR-mPCR). Higher ARs were associated with lower FMR1 transcript levels for any given repeat length. The higher AR-Sb was significantly associated with performance, verbal, and full-scale IQ scores, confirming previous reports. However, the AR-mPCR was not significantly associated (p > 0.05) with these measures. Similarly, the odds of depression and the number of medical conditions were correlated with higher AR-Sb but not correlated with a higher AR-mPCR. This study suggests that AR-Sb may be a more reliable measure of the AR in female carriers of PM alleles. However, further studies are warranted in a larger sample size to fully evaluate the methylation status in these participants and how it may affect the clinical phenotype.

The Nomological Network of a Behavioral Distress Tolerance Task in Veterans

There is a relative lack of research on distress tolerance (DT) in veteran samples. The aims of the study were to (a) evaluate convergent and discriminant validity of a behavioral measure of DT compared to theoretically similar (i.e., self-report DT, negative urgency) and dissimilar (i.e., risk-taking) constructs and (b) evaluate the concurrent validity of DT in relation to posttraumatic stress disorder (PTSD) and depressive symptoms in a veteran sample. A sample of U.S. veterans who served after the September 11, 2001 terror attacks (N = 306, 89.9% male; M age 30.2 years, SD = 4.5, range: 21-40 years) completed self-report and behavioral measures of DT, risk-taking, impulsivity, and depressive symptoms, and completed a clinical interview for PTSD. Results of a multitrait-multimethod matrix found significant yet minimal shared variance, r2 = .01-.03, ps = .002-.055, between the self-report and behavioral measures of DT. We used a series of multiple regressions to examine the relative contribution of the behavioral and self-report DT measures in the prediction of PTSD and depressive symptoms. Self-reported, but not behavioral, DT accounted for unique variance in PTSD, r2 = .12, p < .001, and depressive symptoms, r2 = .23, p < .001. Participants with PTSD or higher scores on measures of depression were more likely to report greater increases in frustration and irritability after completing the behavioral task. Results indicate that DT is not a unidimensional construct and must be considered in the context of specific emotions (e.g., tolerance of irritability vs. fear) and contexts (e.g., behavioral, affective).

The Post-Deployment Mental Health (PDMH) study and repository: A multi-site study of US Afghanistan and Iraq era veterans

The United States (US) Department of Veterans Affairs (VA) Mid-Atlantic Mental Illness Research, Education, and Clinical Center (MIRECC) Post-Deployment Mental Health (PDMH) multi-site study examines post-deployment mental health in US military Afghanistan/Iraq-era veterans. The study includes the comprehensive behavioral health characterization of over 3600 study participants and the genetic, metabolomic, neurocognitive, and neuroimaging data for many of the participants. The study design also incorporates an infrastructure for a data repository to re-contact participants for follow-up studies. The overwhelming majority (94%) of participants consented to be re-contacted for future studies, and our recently completed feasibility study indicates that 73-83% of these participants could be reached successfully for enrollment into longitudinal follow-up investigations. Longitudinal concurrent cohort follow-up studies will be conducted (5-10+ years post-baseline) to examine predictors of illness chronicity, resilience, recovery, functional outcome, and other variables, and will include neuroimaging, genetic/epigenetic, serum biomarker, and neurocognitive studies, among others. To date, the PDMH study has generated more than 35 publications from the baseline data and the repository has been leveraged in over 20 publications from follow-up studies drawing from this cohort. Limitations that may affect data collection for a longitudinal follow-up study are also presented.