George D. Papandonatos
Brown University
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Featured researches published by George D. Papandonatos.
Development and Psychopathology | 2009
Laura R. Stroud; Elizabeth Foster; George D. Papandonatos; Kathryn Handwerger; Douglas A. Granger; Katie T. Kivlighan; Raymond Niaura
Little is known about normative variation in stress response over the adolescent transition. This study examined neuroendocrine and cardiovascular responses to performance and peer rejection stressors over the adolescent transition in a normative sample. Participants were 82 healthy children (ages 7-12 years, n = 39, 22 females) and adolescents (ages 13-17, n = 43, 20 females) recruited through community postings. Following a habituation session, participants completed a performance (public speaking, mental arithmetic, mirror tracing) or peer rejection (exclusion challenges) stress session. Salivary cortisol, salivary alpha amylase (sAA), systolic and diastolic blood pressure (SBP, DBP), and heart rate were measured throughout. Adolescents showed significantly greater cortisol, sAA, SBP, and DBP stress response relative to children. Developmental differences were most pronounced in the performance stress session for cortisol and DBP and in the peer rejection session for sAA and SBP. Heightened physiological stress responses in typical adolescents may facilitate adaptation to new challenges of adolescence and adulthood. In high-risk adolescents, this normative shift may tip the balance toward stress response dysregulation associated with depression and other psychopathology. Specificity of physiological response by stressor type highlights the importance of a multisystem approach to the psychobiology of stress and may also have implications for understanding trajectories to psychopathology.
Nicotine & Tobacco Research | 2005
Nathan K. Cobb; Amanda L. Graham; Beth C. Bock; George D. Papandonatos; David B. Abrams
To significantly reduce smoking prevalence, treatments must balance reach, efficacy, and cost. The Internet can reach millions of smokers cost-effectively. Many cessation Web sites exist, but few have been evaluated. As a result, the potential impact of the Internet on smoking prevalence remains unknown. The present study reports the results, challenges, and limitations of a preliminary, large-scale evaluation of a broadly disseminated smoking cessation Web site used worldwide (QuitNet). Consecutive registrants (N=1,501) were surveyed 3 months after they registered on the Web site to assess 7-day point prevalence abstinence. Results must be interpreted cautiously because this is an uncontrolled study with a 25.6% response rate. Approximately 30% of those surveyed indicated they had already quit smoking at registration. Excluding these participants, an intention-to-treat analysis yielded 7% point prevalence abstinence (for the responders only, abstinence was 30%). A range of plausible cessation outcomes (9.8%-13.1%) among various subgroups is presented to illustrate the strengths and limitations of conducting Web-based evaluations, and the tensions between clinical and dissemination research methods. Process-to-outcome analyses indicated that sustained use of QuitNet, especially the use of social support, was associated with more than three times greater point prevalence abstinence and more than four times greater continuous abstinence. Despite its limitations, the present study provides useful information about the potential efficacy, challenging design and methodological issues, process-to-outcome mechanisms of action, and potential public health impact of Internet-based behavior change programs for smoking cessation.
Health Psychology | 2007
Bess H. Marcus; M Napolitano; Abby C. King; Beth Lewis; J. A. Whiteley; Anna E. Albrecht; Alfred F. Parisi; Beth C. Bock; Bernardine M. Pinto; Christopher N. Sciamanna; John M. Jakicic; George D. Papandonatos
OBJECTIVE Given that only 25% of Americans meet physical activity recommendations, there is a need to develop and disseminate effective, evidence-based interventions to promote physical activity. The authors tested 2 delivery channels, telephone and print, to determine whether one was more effective in promoting physical activity. DESIGN The authors randomly assigned 239 healthy, sedentary adults to (a) telephone-based individualized feedback, (b) print-based individualized feedback, or (c) contact control. Both intervention arms were guided by a motivationally tailored, theoretically driven computer expert system. MAIN OUTCOME MEASURES Physical activity as measured by the 7-day Physical Activity Recall interview. RESULTS At 6 months, both telephone and print arms significantly increased in minutes of moderate intensity physical activity compared with control, with no differences between the intervention arms. At 12 months, print participants reported a significantly greater number of moderate intensity minutes than both telephone and control participants, who did not differ. CONCLUSION Results suggest that both telephone and print enhance the adoption of physical activity among sedentary adults; however, print interventions may be particularly effective in maintaining physical activity in the longer term.
Neurology | 2008
Brian R. Ott; William C. Heindel; George D. Papandonatos; Elena K. Festa; Jennifer D. Davis; Lori A. Daiello; John C. Morris
Objective: The goal of this study was to define the natural progression of driving impairment in persons who initially have very mild to mild dementia. Methods: We studied 128 older drivers, including 84 with early Alzheimer disease (AD) and 44 age-matched control subjects without cognitive impairment. Subjects underwent repeated assessments of their cognitive, neurologic, visual, and physical function over 3 years. Self-reports of driving accidents and traffic violations were supplemented by reports from family informants and state records. Within 2 weeks of the office evaluation, subjects were examined by a professional driving instructor on a standardized road test. Results: At baseline, subjects with AD had experienced more accidents and performed more poorly on the road test, compared to controls. Over time, both groups declined in driving performance on the road test, with subjects with AD declining more than controls. Survival analysis indicated that while the majority of subjects with AD passed the examination at baseline, greater severity of dementia, increased age, and lower education were associated with higher rates of failure and marginal performance. Conclusions: This study confirms previous reports of potentially hazardous driving in persons with early Alzheimer disease, but also indicates that some individuals with very mild dementia can continue to drive safely for extended periods of time. Regular follow-up assessments, however, are warranted in those individuals.
Journal of Consulting and Clinical Psychology | 2008
Rena R. Wing; George D. Papandonatos; Joseph L. Fava; Amy A. Gorin; Suzanne Phelan; Jeanne M. McCaffery; Deborah F. Tate
Few studies have examined predictors of weight regain after significant weight losses. This prospective study examined behavioral and psychological predictors of weight regain in 261 successful weight losers who completed an 18-month trial of weight regain prevention that compared a control condition with self-regulation interventions delivered face-to-face or via the Internet. Linear mixed effect models were used to examine behavioral and psychological predictors of weight regain, both as main effects and as interactions with treatment group. Decreases in physical activity were related to weight regain across all 3 groups, and increased frequency of self-weighing was equally protective in the 2 intervention groups but not in the control group. Increases in depressive symptoms, disinhibition, and hunger were also related to weight regain in all groups. Although the impact of changes in restraint was greatest in the Internet group and weakest in the face-to-face group, the latter was the only group with increases in restraint over time and consequent decreases in magnitude of weight regain. Future programs should focus on maintaining physical activity, dietary restraints, and frequent self-weighing and should include stronger components to modify psychological parameters.
Health Psychology | 2006
Kathleen Forcier; Laura R. Stroud; George D. Papandonatos; Brian Hitsman; Meredith W. Reiches; Jenelle Krishnamoorthy; Raymond Niaura
A meta-analysis of published studies with adult human participants was conducted to evaluate whether physical fitness attenuates cardiovascular reactivity and improves recovery from acute psychological stressors. Thirty-three studies met selection criteria; 18 were included in recovery analyses. Effect sizes and moderator influences were calculated by using meta-analysis software. A fixed effects model was fit initially; however, between-studies heterogeneity could not be explained even after inclusion of moderators. Therefore, to account for residual heterogeneity, a random effects model was estimated. Under this model, fit individuals showed significantly attenuated heart rate and systolic blood pressure reactivity and a trend toward attenuated diastolic blood pressure reactivity. Fit individuals also showed faster heart rate recovery, but there were no significant differences in systolic blood pressure or diastolic blood pressure recovery. No significant moderators emerged. Results have important implications for elucidating mechanisms underlying effects of fitness on cardiovascular disease and suggest that fitness may be an important confound in studies of stress reactivity.
Experimental and Clinical Psychopharmacology | 1998
Collins Rl; Morsheimer Et; Saul Shiffman; Jean A. Paty; Maryann Gnys; George D. Papandonatos
We assessed predictors of self-reported excessive drinking (> 5 drinks) in a sample of heavy drinkers. Participants were randomly assigned to moderation training or a waiting-list control condition. They were trained in ecological momentary assessment (EMA) involving self-monitoring of drinking and other variables on a small hand-held computer, the electronic diary (ED). During the 8-week study, participants were compliant in their use of the ED for both random prompts and the entry of data related to specific drinking episodes. Generalized estimating equations were used to fit models involving predictors related to past history of drinking, aspects of the training program, drinking restraint, and episode-specific mood. The models indicated robust predictors of decreased and increased drinking. Our results suggest that EMA is a useful methodology for assessing drinking and related behaviors.
Neurology | 2009
Selim R. Benbadis; W. C. LaFrance; George D. Papandonatos; K. Korabathina; Kaiwen Lin; Helena C. Kraemer
Objective: The diagnosis of psychogenic nonepileptic seizures (PNES) can be challenging. In the absence of a gold standard to verify the reliability of the diagnosis by EEG-video, we sought to assess the interrater reliability of the diagnosis using EEG-video recordings. Methods: Patient samples consisted of 22 unselected consecutive patients who underwent EEG-video monitoring and had at least an episode recorded. Other test results and histories were not provided because the goal was to assess the reliability of the EEG-video. Data were sent to 22 reviewers, who were board-certified neurologists and practicing epileptologists at epilepsy centers. Choices were 1) PNES, 2) epilepsy, and 3) nonepileptic but not psychogenic (“physiologic”) events. Interrater agreement was measured using a κ coefficient for each diagnostic category. We used generalized κ coefficients, which measure the overall level of between-method agreement beyond that which can be ascribed to chance. We also report category-specific κ values. Results: For the diagnosis of PNES, there was moderate agreement (κ = 0.57, 95% confidence interval [CI] 0.39–0.76). For the diagnosis of epilepsy, there was substantial agreement (κ = 0.69, 95% CI 0.51–0.86). For physiologic nonepileptic episodes, the agreement was low (κ = 0.09, 95% CI 0.02–0.27). The overall κ statistic across all 3 diagnostic categories was moderate at 0.56 (95% CI 0.41–0.73). Conclusions: Interrater reliability for the diagnosis of psychogenic nonepileptic seizures by EEG-video monitoring was only moderate. Although this may be related to limitations of the study (diagnosis based on EEG-video alone, artificial nature of the forced choice paradigm, single episode), it highlights the difficulties and subjective components inherent to this diagnosis.
Neurology | 2010
W. C. LaFrance; Gabor I. Keitner; George D. Papandonatos; Andrew S. Blum; Jason T. Machan; Christine E. Ryan; Ivan W. Miller
Objective: There have been few treatment trials for psychogenic nonepileptic seizures (PNES). Some psychotherapies have been shown to improve PNES and comorbid symptom outcomes. We evaluated a pharmacologic intervention to test the hypothesis that sertraline would reduce PNES. Methods: We conducted a pilot, double-blind, randomized, placebo-controlled trial in an academic medical hospital with epilepsy center outpatients. Subjects aged 18 to 65 years diagnosed with video-EEG–confirmed PNES were treated with flexible-dose sertraline or placebo over 12 weeks. Seizure calendars and symptom scales were charted prospectively. Secondary outcome measures included psychiatric symptom scales and psychosocial variables. Results: Thirty-eight subjects enrolled, and 26 (68%) completed the trial. Thirty-three subjects with nonzero nonepileptic seizure rates at baseline were included in intent-to-treat analysis of the primary outcome. Subjects assigned to the sertraline arm experienced a 45% reduction in seizure rates from baseline to final visit (p = 0.03) vs an 8% increase in placebo (p = 0.78). Secondary outcome scales revealed no significant between-group differences in change scores from baseline to final visit, after adjustment for differences at baseline. Conclusions: PNES were reduced in patients treated with a serotonin selective reuptake inhibitor, whereas those treated with placebo slightly increased. This study provides feasibility data for a larger-scale study. Level of evidence: This study provides Class II evidence that flexible-dose sertraline up to a maximum dose of 200 mg is associated with a nonsignificant reduction in PNES rate compared with a placebo control arm (risk ratio 0.51, 95% confidence interval 0.25–1.05, p = 0.29), adjusting for differences at baseline.
Journal of the American Geriatrics Society | 2005
Laura B. Brown; Brian R. Ott; George D. Papandonatos; Yunxia Sui; Rebecca E. Ready; John C. Morris
Objectives: Physicians and family members frequently are asked to provide information about driving ability in patients with Alzheimers disease (AD), yet there has been little research on the validity of their assessments of driving performance.