Biomedical subjects

T M Keane

Publications and source records attributed to T M Keane.

At least 19 recordsLinked to original sources

PubMed2005

Utility of the HIV dementia scale in assessing risk for significant HIV-related cognitive-motor deficits in a high-risk urban adult sample.

Considerable literature reflects the range of HIV-related neurocognitive complications, including relatively poor performance on tests of: movement and coordination; attention and concentration; reaction time; and mental flexibility. Efforts to develop appropriate screening techniques include the HIV Dementia Scale (HDS), a brief measure that has demonstrated promise but is lacking extensive independent evaluation. The present study examines the utility of the HDS in a sample of HIV-seropositive adults with a co-morbid history of psychiatric and substance use disorders. Forty subjects (65% male; mean age 41 years; mean education 12.2 years; 55% African American, 30% Caucasian) recruited for a study of the impact of brief psychotherapy on adherence to medications and medical appointments, relapse prevention, and/or enhancement of mental health functioning completed a battery of neuropsychological measures, including the HDS. Forty percent were identified as at high risk for significant cognitive-motor disorder (HDS total score < or =10). After controlling for age, education, illness (absolute CD4), and depressed mood, high-risk participants performed significantly worse on measures of simple and sustained divided attention, psychomotor speed, and working memory. However, only 25 of 40 (63%) were correctly classified based on their performance on traditional tests of neuropsychological functioning. Implications and limitations of the study are discussed.

AIDS Dementia Complex↗

PubMed2004

DSEARCH: sensitive database searching using distributed computing.

UNLABELLED: We present a distributed and fully cross-platform database search program that allows the user to utilize the idle clock cycles of machines to perform large searches using the most sensitive algorithms. For those in an academic or corporate environment with hundreds of idle desktop machines, DSEARCH can deliver a 'free' database search supercomputer. AVAILABILITY: The software is publicly available under the GNU general public licence from http://www.cs.may.ie/distributed CONTACT: tom.naughton@may.ie SUPPLEMENTARY INFORMATION: Full documentation and a user manual is available from http://www.cs.may.ie/distributed.

Algorithms↗

PubMed2004

DPRml: distributed phylogeny reconstruction by maximum likelihood.

MOTIVATION: In recent years there has been increased interest in producing large and accurate phylogenetic trees using statistical approaches. However for a large number of taxa, it is not feasible to construct large and accurate trees using only a single processor. A number of specialized parallel programs have been produced in an attempt to address the huge computational requirements of maximum likelihood. We express a number of concerns about the current set of parallel phylogenetic programs which are currently severely limiting the widespread availability and use of parallel computing in maximum likelihood-based phylogenetic analysis. RESULTS: We have identified the suitability of phylogenetic analysis to large-scale heterogeneous distributed computing. We have completed a distributed and fully cross-platform phylogenetic tree building program called distributed phylogeny reconstruction by maximum likelihood. It uses an already proven maximum likelihood-based tree building algorithm and a popular phylogenetic analysis library for all its likelihood calculations. It offers one of the most extensive sets of DNA substitution models currently available. We are the first, to our knowledge, to report the completion of a distributed phylogenetic tree building program that can achieve near-linear speedup while only using the idle clock cycles of machines. For those in an academic or corporate environment with hundreds of idle desktop machines, we have shown how distributed computing can deliver a 'free' ML supercomputer.

Algorithms↗

PubMed2004

Understanding the interface of HIV, trauma, post-traumatic stress disorder, and substance use and its implications for health outcomes.

Many individuals living with HIV have been exposed to some type of traumatic event during their lives and may be living with symptoms of post-traumatic stress disorder (PTSD). A substantial number of these individuals are also likely to show evidence of a co-morbid substance use disorder (SUD). There is reason to believe that the co-occurrence of HIV and PTSD or co-morbid PTSD and SUD (PTSD/SUD) may predict poorer health outcomes. There are several pathways through which PTSD or PTSD/SUD might adversely impact the health of individuals living with HIV, including participation in negative health behaviours, low levels of adherence to antiretroviral medications, and/or a direct, deleterious effect on immune function. Psychological interventions are needed to treat PTSD and PTSD/SUD in HIV-positive individuals, and reduce the negative impact of these conditions on health outcomes. This article will explore data on the prevalence of trauma exposure, PTSD, and PTSD/SUD among individuals living with HIV, the pathways through which these conditions might affect health, possible interventions for PTSD and PTSD/SUD for individuals living with HIV, and methods for integrating care for individuals with these disorders. Future directions for research related to HIV, PTSD, and PTSD/SUD will also be discussed.

Attitude to Health↗

PubMed2001

Clinician-administered PTSD scale: a review of the first ten years of research.

The Clinician-Administered PTSD Scale (CAPS) is a structured interview for assessing posttraumatic stress disorder (PTSD) diagnostic status and symptom severity. In the 10 years since it was developed, the CAPS has become a standard criterion measure in the field of traumatic stress and has now been used in more than 200 studies. In this paper, we first trace the history of the CAPS and provide an update on recent developments. Then we review the empirical literature, summarizing and evaluating the findings regarding the psychometric properties of the CAPS. The research evidence indicates that the CAPS has excellent reliability, yielding consistent scores across items, raters, and testing occasions. There is also strong evidence of validity: The CAPS has excellent convergent and discriminant validity, diagnostic utility, and sensitivity to clinical change. Finally, we address several concerns about the CAPS and offer recommendations for optimizing the CAPS for various clinical research applications.

Case-Control Studies↗

PubMed2000

Predictors of emotional numbing, revisited: a replication and extension.

Litz et al. (1997), theorizing that emotional numbing (EN) is the result of emotional depletion caused by chronic hyperarousal, demonstrated that a cluster of hyperarousal symptoms was a robust predictor of EN symptoms. In the present study, these findings were replicated and extended in two multiple regression analyses of data from a large, multisite investigation (T. M. Keane et al., 1998) of psychophysiological responding by male combat veterans. The arousal (D) cluster of symptoms was again the most robust predictor of EN symptoms, whereas physiological indices of arousal and reactivity accounted for negligible amounts of variance in both regression equations. These findings underscore the possible link between disturbances related to arousal and the capacity of traumatized individuals to express and experience pleasant feelings.

Affect↗

PubMed1999

Posttraumatic stress disorder in a national sample of female and male Vietnam veterans: risk factors, war-zone stressors, and resilience-recovery variables.

Relationships among pretrauma risk factors (e.g., family instability, childhood antisocial behavior), war-zone stressors (e.g., combat, perceived threat), posttrauma resilience-recovery variables (e.g., hardiness, social support), and posttraumatic stress disorder (PTSD) symptom severity were examined. Data from a national sample of 432 female and 1,200 male veterans were analyzed using structural equation modeling. For both genders, direct links to PTSD from pretrauma, war-zone, and posttrauma variable categories were found; several direct associations between pretrauma and posttrauma variables were documented. Although war-zone stressors appeared preeminent for PTSD in men, posttrauma resilience-recovery variables were more salient for women. Researchers, policymakers, and clinicians are urged to take a broad view on trauma and its sequelae, especially regarding possible multiple exposures over time and the depletion and availability of important resources.

Adult↗

PubMed1998

Treatment for traumatic memories: review and recommendations.

The aim of this article is to provide recommendations concerning the use of exposure-based therapy for reduction of emotional responding to traumatic memories. Background for these recommendations consists of a summary of the literature on traumatic stress and symptoms of posttraumatic stress disorder (PTSD); an overview of biological, cognitive, and behavioral models for traumatic memory; and a selective review of evidence for the effectiveness of therapeutic exposure as a treatment for trauma memories and PTSD. The recommendations themselves demonstrate how clinical decision making during the course of treatment might be informed by empirical evidence and theoretical models concerning human memory, as well as ethical and legal considerations that mark this topic.

Animals↗

PubMed1998

Utility of psychophysiological measurement in the diagnosis of posttraumatic stress disorder: results from a Department of Veterans Affairs Cooperative Study.

This multisite study tested the ability of psychophysiological responding to predict posttraumatic stress disorder (PTSD) diagnosis (current, lifetime, or never) in a large sample of male Vietnam veterans. Predictor variables for a logistic regression equation were drawn from a challenge task involving scenes of combat. The equation was tested and cross-validated demonstrating correct classification of approximately 2/3 of the current and never PTSD participants. Results replicate the finding of heightened psychophysiological responding to trauma-related cues by individuals with current PTSD, as well as differences in a variety of other domains between groups with and without the disorder. Follow-up analyses indicate that veterans with current PTSD who do not react physiologically to the challenge task manifest less reexperiencing symptoms, depression, and guilt. Discussion addresses the value of psychophysiological measures for assessment of PTSD.

Adolescent↗

PubMed1998

Resilience-recovery factors in post-traumatic stress disorder among female and male Vietnam veterans: hardiness, postwar social support, and additional stressful life events.

Structural equation modeling procedures were used to examine relationships among several war zone stressor dimensions, resilience-recovery factors, and post-traumatic stress disorder symptoms in a national sample of 1,632 Vietnam veterans (26% women and 74% men). A 9-factor measurement model was specified on a mixed-gender subsample of the data and then replicated on separate subsamples of female and male veterans. For both genders, the structural models supported strong mediation effects for the intrapersonal resource characteristic of hardiness, postwar structural and functional social support, and additional negative life events in the postwar period. Support for moderator effects or buffering in terms of interactions between war zone stressor level and resilience-recovery factors was minimal.

Adaptation, Psychological↗

PubMed1998

Head injury and combat-related posttraumatic stress disorder.

Given the association of injury and posttraumatic stress disorder (PTSD), we examined whether head injury might be associated with increased frequency and severity of PTSD. Using a mail survey, we queried 143 male combat veterans with and without PTSD, who had previously participated in PTSD research in our laboratory, about their history of head injury. Respondents with a PTSD diagnosis were significantly more likely to report a history of head injury than those without. Patients with a history of head injury also reported more severe symptoms of PTSD compared with PTSD patients without head injury. The association of head injury and PTSD was not due to greater combat exposure in the head-injured group. Head injury is associated with a greater likelihood of developing combat-related PTSD and with more severe PTSD symptoms. This retrospective study did not address mechanisms that could account for this finding. The results indicate head injury should be systematically assessed by both nonpsychiatric and psychiatric physicians concerned with the psychological sequelae of exposure to victimizing experiences.

Combat Disorders↗

PubMed1997

Comorbid psychiatric disorders in PTSD. Implications for research.

It is clear from the existing data that PTSD often occurs in the context of other major psychological conditions. Evidence to support this comes from clinical studies, epidemiological studies, and studies of PTSD among substance abusers. Clearly, probably several different subgroups of PTSD patients exist including those who had psychological or behavioral problems before exposure to traumatic events (e.g., substance abuse), those who developed other problems concurrent with exposure to the traumatic events, and those who developed problems secondary to the development of PTSD, perhaps in efforts to cope with the intensely debilitating symptoms of PTSD. With this knowledge, research on PTSD must begin to contend with the comorbidity issue in systematic ways. The use of comparison groups that are carefully selected is one key way in which conclusions about PTSD can be most conservatively drawn. The use of statistical procedures to control for difference in levels of comorbidity is another responsible way in which to approach the problem. Finally, efforts to employ global measures of functioning such as the Global Assessment of Functioning to equate subjects within a study on minimally this characteristic may be the most economical method for trying to rule out the role of comorbidity and severity of condition in conclusions drawn in research studies. All these solutions presuppose the careful measurement of comorbidity in studies of PTSD, a recommendation that requires serious consideration for researchers operating in this field.

Comorbidity↗

PubMed1996

Attention, arousal, and memory in posttraumatic stress disorder.

Vietnam combat veterans with current posttraumatic stress disorder (PTSD), with other Axis-I disorders, or with no Axis-I disorders completed a series of tasks designed to elucidate the psychophysiological parameters of information-processing in PTSD. These tasks included a modified Stroop procedure (MSP), a standard Stroop procedure, a recognition memory task, and a threat rating task. Physiological responses were recorded throughout the study. Our data supported several predictions derived from information-processing models of PTSD. PTSD subjects exhibited greater MSP interference to high threat words than both comparison groups, and a liberal response bias toward recognizing military-related words. PTSD symptoms and threat reactions contributed to MSP interference effects for high-threat words after controlling for medications, depression, and baseline physiological activity.

Adult↗

PubMed1996

The utility of the SCL-90-R for the diagnosis of war-zone related posttraumatic stress disorder.

A scale for assessing war-zone-related posttraumatic stress disorder (WZ-PTSD scale) was derived from the Symptom Checklist-90-R by identifying items that best discriminated Vietnam theater veterans with and without PTSD (N = 202). The 25-item WZ-PTSD scale had excellent internal consistency, and signal detection analyses revealed that its diagnostic utility was comparable to or exceeded that of several established PTSD scales and measures of global distress. In a cross-validation sample (N = 99), the diagnostic utility of the WZ-PTSD scale was stable, whereas other PTSD scales performed more poorly. The WZ-PTSD scale appears to be a valuable new measure of PTSD that can be particularly useful in archival data sets or in any situation where other PTSD measures are not available.

Adult↗

PubMed1996

Current and lifetime psychiatric disorders among veterans with war zone-related posttraumatic stress disorder.

Previous research has found high rates of psychiatric disorders among veterans with war zone-related posttraumatic stress disorder (PTSD). However, many studies in this area are methodologically limited in ways that preclude unambiguous interpretation of their results. The purpose of this study was to address some of these limitations to clarify the relationship between war zone-related PTSD and other disorders. Participants were 311 male Vietnam theater veterans assessed at the National Center for PTSD at the Boston Veterans Affairs Medical Center. The Clinician-Administered PTSD Scale and the Structured Clinical Interview for DSM-III-R were used to derive current and lifetime diagnoses of PTSD, other axis I disorders (mood, anxiety, substance use, psychotic, and somatoform disorders), and two axis II disorders (borderline and antisocial personality disorders only). Participants also completed several self-report measures of PTSD and general psychopathology. Relative to veterans without PTSD, veterans with PTSD had significantly higher rates of current major depression, bipolar disorder, panic disorder, and social phobia, as well as significantly higher rates of lifetime major depression, panic disorder, social phobia, and obsessive-compulsive disorder. In addition, veterans with PTSD scored significantly higher on all self-report measures of PTSD and general psychopathology. These results provide further evidence that PTSD is associated with high rates of additional psychiatric disorders, particularly mood disorders and other anxiety disorders. The implications of these findings and suggestions about the direction of future research in this area are discussed.

Adult↗

PubMed1995

The development of a Clinician-Administered PTSD Scale.

Several interviews are available for assessing PTSD. These interviews vary in merit when compared on stringent psychometric and utility standards. Of all the interviews, the Clinician-Administered PTSD Scale (CAPS-1) appears to satisfy these standards most uniformly. The CAPS-1 is a structured interview for assessing core and associated symptoms of PTSD. It assesses the frequency and intensity of each symptom using standard prompt questions and explicit, behaviorally-anchored rating scales. The CAPS-1 yields both continuous and dichotomous scores for current and lifetime PTSD symptoms. Intended for use by experienced clinicians, it also can be administered by appropriately trained paraprofessionals. Data from a large scale psychometric study of the CAPS-1 have provided impressive evidence of its reliability and validity as a PTSD interview.

Humans↗

PubMed1994

An in vivo assessment of physiological arousal in posttraumatic stress disorder.

The present study measured physiological function (heart rate [HR], systolic blood pressure [SBP], diastolic blood pressure [DBP], sublingual temperature, and respiration rate) in a nonresearch setting--the medical triage area of a large Veterans Affairs Medical Center while patients were awaiting physical examination. Subjects were 32 Vietnam veterans with combat-related posttraumatic stress disorder (PTSD) and 26 Vietnam-era veterans with no combat experience. Results indicated that PTSD veterans had significantly higher HR, SBP, and DBP, but not sublingual temperature or respiration rate. These data support the position that individuals with PTSD do indeed demonstrate higher levels of cardiovascular arousal across settings.

Adult↗

PubMed1992

Post-traumatic stress disorder and coping in veterans who are seeking medical treatment.

The present study examined psychological coping styles and mental health treatment histories in veterans with PTSD. This study also served as a replication and extension of an earlier investigation that assessed the prevalence of PTSD in World War II, Korea, and Vietnam combat veterans who were seeking medical treatment. Thirty-six combat veteran medical patients were compared to 38 war-era controls. Nearly a third of the combat veterans met psychometric criteria for PTSD; none of the controls met these criteria. Both PTSD-positive subjects and mental health treatment seekers showed a significantly greater use of emotion-focused coping. Results also showed that Vietnam combatants were more likely to have received individual mental health treatment. These findings and their treatment implications are discussed.

Adaptation, Psychological↗