Dmitri Poltavski

Assessing Health Status, Behavioral Risks, and Health Disparities in American Indians Living on the Northern Plains of the U.S.

Objective. We assessed health status and behavioral risks in American Indians (AIs) from rural, northern plains reservation communities. Methods. AI interviewers from the communities administered the core and optional modules of the Behavioral Risk Factor Surveillance System (BRFSS) to 404 AI adults randomly selected from housing lists from four AI tribal communities located on the northern plains of the U.S. The BRFSS interview assessed several health functioning areas including medical conditions, preventive screenings, and behavioral risks. We measured health disparities by comparing the AI sample data with a northern plains statewide (North Dakota) sample and a U.S. national sample. We compared outcomes with BRFSS statewide (North Dakota) and U.S. national data from telephone-based interviews. Results. AI participants showed a significantly greater prevalence of diabetes, coronary heart disease, myocardial infarction, smoking, obesity, and heavy alcohol use than either the regional or national samples. They also reported being less likely to engage in leisure-time physical activity and to have had age-appropriate preventive screenings for several diseases including colorectal cancer, prostate cancer, breast cancer, and cardiovascular disease. Conclusions. Face-to-face interviews conducted by AI community members are an effective means of gathering health information about AIs living in rural, reservation communities. AIs living in these communities on the northern plains have a much higher prevalence of many health-risk behaviors and some medical conditions than are found in the general population. Improved health-care access, better preventive screenings, and culturally appropriate community-based health promotion programs and policies should be examined as possible ways to reduce health disparities.

Effects of transdermal nicotine on prose memory and attention in smokers and nonsmokers

Previous research investigating cognitive effects of nicotine has produced mixed findings partly due to the use of abstaining smokers and cigarettes as a delivery system. The present study examined effects of nicotine delivered via a transdermal patch on prose memory and sustained attention in male smokers (n=25) and nonsmokers (n=22), who were randomly assigned to either a placebo or a nicotine condition. All groups were matched on their verbal ability and gross personality characteristics (state/trait anxiety levels, extroversion-introversion, and impulsivity level). In the nicotine condition, smokers were treated with a 21-mg transdermal patch, while nonsmokers received a 7-mg nicotine patch. Six hours following patch application, their performance was assessed on a computerized prose memory task and the Rapid Visual Information Processing task (RVIP) in a counterbalanced order and double-blind fashion. The results demonstrated that smokers in the placebo group recalled a significantly greater number of propositions than their counterparts in the nicotine group. Nonsmokers in the nicotine condition also remembered significantly more of the prose material than smokers in the same condition and showed a trend towards better recall of propositions of medium importance in the nicotine condition in comparison to the nonsmokers in the placebo group. No between-group differences were found on the RVIP task. A significant effect of time was found for systolic blood pressure and heart rate. The results cannot be interpreted using the arousal theory of nicotine effects on attention and are explained on the basis of a dose-dependent nicotinic action possibly recruiting cholinergic cortical projections.

The role of visual perception measures used in sports vision programmes in predicting actual game performance in Division I collegiate hockey players

Abstract In the growing field of sports vision little is still known about unique attributes of visual processing in ice hockey and what role visual processing plays in the overall athlete’s performance. In the present study we evaluated whether visual, perceptual and cognitive/motor variables collected using the Nike SPARQ Sensory Training Station have significant relevance to the real game statistics of 38 Division I collegiate male and female hockey players. The results demonstrated that 69% of variance in the goals made by forwards in 2011–2013 could be predicted by their faster reaction time to a visual stimulus, better visual memory, better visual discrimination and a faster ability to shift focus between near and far objects. Approximately 33% of variance in game points was significantly related to better discrimination among competing visual stimuli. In addition, reaction time to a visual stimulus as well as stereoptic quickness significantly accounted for 24% of variance in the mean duration of the player’s penalty time. This is one of the first studies to show that some of the visual skills that state-of-the-art generalised sports vision programmes are purported to target may indeed be important for hockey players’ actual performance on the ice.

Screening for lifetime concussion in athletes: Importance of oculomotor measures

Abstract Hypothesis/objective: The purpose of the present study was to determine the utility of oculomotor-based evaluation protocols in screening for lifetime concussion incidence in elite hockey players. Methods: Forty-two Division I collegiate male and female hockey players were evaluated using the guidelines of an overall oculomotor-based diagnostic clinical test protocol for the mTBI population. The sensitivity of the collected measures to lifetime concussion was then compared with the corresponding sensitivity of measures of neuropsychological functioning (ImPACT) often used with athletes for acute concussion diagnosis. Results: This model showed that a hockey player with a Near Point of Fixation Disparity (NPFD) equal to or greater than 15 cm, Visagraph comprehension rate less than 85% and the total score on part A of an ADHD questionnaire equal to or greater than 11 was on average 10.72-times more likely to have previously suffered a concussion than an athlete with lower values on the NPFD and ADHD questionnaire and a higher comprehension rate on the Visagraph. None of the IMPACT baseline assessment measures were significantly predictive of the individual’s concussion history. Conclusion: The study provides a relatively sensitive screening tool to assess the probability of previous concussion(s) in an athlete. This model may allow athletic personnel to address in a timely manner the risks associated with repeat concussions and to develop individualized concussion management protocols.

Delay and probability discounting of multiple commodities in smokers and never-smokers using multiple-choice tasks

The purpose of the present study was to investigate temporal and probabilistic discounting in smokers and never-smokers, across a number of commodities, using a multiple-choice method. One hundred and eighty-two undergraduate university students, of whom 90 had never smoked, 73 were self-reported light smokers (<10 cigarettes/day), and 17 were heavy smokers (10+cigarettes/day), completed computerized batteries of delay and probability discounting questions pertaining to a total of eight commodities and administered in a multiple-choice format. In addition to cigarettes, monetary rewards, and health outcomes, the tasks included novel commodities such as ideal dating partner and retirement income. The results showed that heavy smokers probability discounted commodities at a significantly shallower rate than never-smokers, suggesting greater risk-taking. No effect of smoking status was observed for delay discounting questions. The only commodity that was probability discounted significantly less than others was ‘finding an ideal dating partner’. The results suggest that probability discounting tasks using the multiple-choice format can discriminate between non-abstaining smokers and never-smokers and could be further explored in the context of behavioral and drug addictions.

Stress and illness in American and Russian college students

The differences in perceptions of potentially stressful events among 139 college students from Russia and USA were investigated in relation to somatic illness. Individual interpretations were assessed using the Life Events Survey. The instrument was administered in conjunction with the State-Trait Anxiety Index. Results indicated more perceived stress by the Russian student sample but more frequent incidence of reported illness in the American student sample. American female college students showed greater anxiety levels and more perceived stress in comparison to male students. Females also reported a greater number of illness occurrences.

Relationships Between Health Behaviors and Weight Status in American Indian and White Rural Children

PURPOSE Preventing obesity in childhood is an increasingly important public health goal. Prevention efforts can be improved by better understanding relationships between health behaviors and overweight and obesity. This study examined such relationships in young American Indian and white children living in the rural United States. METHODS Self-report measures of diet, screen time (passive and active), and physical activity were combined with cardiovascular fitness in cross-sectional analyses to predict weight categories based on body mass index percentiles in 306 American Indian and white children (aged 8-9 years) from a rural area in the upper Midwestern United States. FINDINGS Multinomial logistic regression models were statistically significant for girls (χ2 [20] = 42.73, P < .01), boys (χ2 [20] = 50.44, P < .001), American Indian (χ2 [20] = 36.67, P < .05), and white children (χ2 [20] = 55.99, P < .001). Obesity was associated with poorer cardiovascular fitness in girls (OR = 0.82), boys (OR = 0.83), American Indian (OR = 0.79), and white children (OR = 0.85), and with passive screen time in girls (OR = 1.69), boys (OR = 2.1), and white children (OR = 1.81). Overweight was associated with passive screen time (OR = 2.24) and inversely with active screen time (OR = 0.54), but only in boys. CONCLUSIONS Logistic regression models were more successful at predicting obesity than overweight in all groups of participants. Poorer cardiovascular fitness showed the strongest and most consistent association with obesity, but passive screen time was also a significant and important contributor to the prediction of obesity in most prediction models. Prediction models were similar in girls, boys, American Indian, and white children.

Effects of acute alcohol intoxication on verbal memory in young men as a function of time of day

This experiment examined whether the time of day of alcohol administration influences alcohol metabolism and the impact of alcohol on verbal memory. It was hypothesized that circadian fluctuations in endogenous levels of testosterone in young men would differentially affect blood alcohol levels, which would consequently impair their memory performance to a different degree. Participants were administered alcohol or placebo drinks either at 8am or 6pm and recall of 4 prose passages was examined. The results indicated that recall declined for subjects administered alcohol but time of day did not moderate these effects. Nevertheless, generally alcohol breath levels changed in the predicted direction as a function of the time of the day with higher levels recorded in the morning and lower levels in the afternoon. The results suggested that observed differences in breath alcohol levels may be influenced by differences in endogenous levels of testosterone, but the effect of this presumed interaction on verbal memory appears inconclusive.

The Role of Fear and Disgust in Predicting the Effectiveness of Television Advertisements That Graphically Depict the Health Harms of Smoking

Introduction Antismoking television advertisements that depict the graphic health harms of smoking are increasingly considered best practices, as exemplified by the Centers for Disease Control and Prevention’s current national campaign. Evaluation of responses to these widely used advertisements is important to determine advertisements that are most effective and their mechanisms of action. Our study tested the hypothesis that advertisements rated highest in fear- and disgust-eliciting imagery would be rated as the most effective. Methods Our laboratory study included 144 women and men aged 18 to 33; 84% were current nonsmokers. All participants viewed 6 antismoking television advertisements that depicted the health harms of smoking; they rated their responses of fear and disgust and the effectiveness of the advertisements. We used multilevel modeling to test the effects of the following in predicting effectiveness: fear, disgust, the fear–disgust interaction, the advertisement, and the participant’s sex and smoking status. Follow-up analyses examined differences in ratings of fear, disgust, and effectiveness. Results Advertisement, fear, disgust, and the fear–disgust interaction were each significant predictors of effectiveness. Smoking status and sex were not significant predictors. The 3 advertisements that elicited the highest ratings of fear and disgust were rated the most effective. Conclusion Our findings support the hypothesis that antismoking advertisements of health harms that elicit the greatest responses of fear or disgust are the most effective. When advertisements elicit high ratings of both fear and disgust, advertisements with graphic imagery are effective, whereas advertisements without graphic imagery are not.

Visually Evoked Potential Markers of Concussion History in Patients with Convergence Insufficiency.

ABSTRACT Purpose We investigated whether differences in the pattern visual evoked potentials exist between patients with convergence insufficiency and those with convergence insufficiency and a history of concussion using stimuli designed to differentiate between magnocellular (transient) and parvocellular (sustained) neural pathways. Methods Sustained stimuli included 2-rev/s, 85% contrast checkerboard patterns of 1- and 2-degree check sizes, whereas transient stimuli comprised 4-rev/s, 10% contrast vertical sinusoidal gratings with column width of 0.25 and 0.50 cycles/degree. We tested two models: an a priori clinical model based on an assumption of at least a minimal (beyond instrumentation’s margin of error) 2-millisecond lag of transient response latencies behind sustained response latencies in concussed patients and a statistical model derived from the sample data. Results Both models discriminated between concussed and nonconcussed groups significantly above chance (with 76% and 86% accuracy, respectively). In the statistical model, patients with mean vertical sinusoidal grating response latencies greater than 119 milliseconds to 0.25-cycle/degree stimuli (or mean vertical sinusoidal latencies >113 milliseconds to 0.50-cycle/degree stimuli) and mean vertical sinusoidal grating amplitudes of less than 14.75 mV to 0.50-cycle/degree stimuli were classified as having had a history of concussion. The resultant receiver operating characteristic curve for this model had excellent discrimination between the concussed and nonconcussed (area under the curve = 0.857; P < .01) groups with sensitivity of 0.92 and specificity of 0.80. Conclusions The results suggest a promising electrophysiological approach to identifying individuals with convergence insufficiency and a history of concussion.