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High quality historical control data, if incorporated, may reduce sample size, trial cost, and duration. A too optimistic use of the data, however, may result in bias under prior-data conflict. Motivated by well-publicized two-arm comparative trials in stroke, we propose a Bayesian design that both adaptively incorporates historical control data and selectively adapt the treatment allocation ratios within an ongoing trial responsively to the relative treatment effects. The proposed design differs from existing designs that borrow from historical controls. As opposed to reducing the number of subjects assigned to the control arm blindly, this design does so adaptively to the relative treatment effects only if evaluation of cumulated current trial data combined with the historical control suggests the superiority of the intervention arm. We used the effective historical sample size approach to quantify borrowed information on the control arm and modified the treatment allocation rules of the doubly adaptive biased coin design to incorporate the quantity. The modified allocation rules were then implemented under the Bayesian framework with commensurate priors addressing prior-data conflict. Trials were also more frequently concluded earlier in line with the underlying truth, reducing trial cost, and duration and yielded parameter estimates with smaller standard errors.

IntroductionNational data suggest tobacco smoke is positively associated with higher glycated hemoglobin (HbA1c) among adults. Our objective was to examine the association between serum cotinine and HbA1c among adolescents without known diabetes.MethodsWe assessed adolescents 12-19 years old (N = 11550) who participated in the 1999-2012 National Health and Nutrition Examination Survey. We applied sampling weights while performing multiple linear regression analyses.ResultsThe prevalence of serum cotinine indicative of no tobacco smoke exposure (TSE, 3 ng/mL) was 17.9% in our sample. Mean (± standard error) HbA1c in participants with no TSE was 5.16% (±0.01), passive TSE was 5.16% (±0.01), and active TSE was 5.14% (±0.01). No differences in HbA1c were found between TSE groups including sex, age, race/ethnicity, education, income, and physical activity or the fully adjusted model with waist circumference. We found cotinine × sex (p = .01) and cotinine × age (p = .02) interactions. There was an association between cotinine and HbA1c for males but not females. Within males, participants with cotinine ≥3 ng/mL (5.26 ± 0.02) had higher mean HbA1c than those with cotinine 0.05-2.99 ng/mL and

Flag football is promoted as a safer alternative to tackle football. This may be 1 reason why participation rates have risen by 39% over the past 3 years. Despite rising participation, epidemiologic research on sport-specific injuries and associated relative risk is lacking. To prospectively document the epidemiology of injuries in youth flag football. Descriptive epidemiology study. Regional and national youth flag football tournaments. Athletes (N = 1939; 1744 boys and 195 girls), ages 6 to 12 years. An athletic trainer prospectively monitored the athletes for sport-related injury and exposures. Athlete risks of injury and injury rates were calculated overall and by sex. Injury characteristics were reported for the total population and by sex. Forty-seven injuries to unique individuals were recorded in 1939 athletes with a total of 9228 athlete-exposures (AEs). The overall risk of injury was 2.4% (95% CI = 1.79%, 3.21%), with an overall injury rate of 5.1 per 1000 AEs (95% CI = 3.75, 6.77). Of the 47 injuries, 36 occurred in boys (8365 AEs), and 11 occurred in girls (863 AEs). A higher risk in girls was evidenced by both the injury risk ratio (2.73; 95% CI = 1.41, 5.30) and injury rate ratio of 2.96 (95% CI = 1.51, 5.82). The most common injury sites were the head/face/neck (n = 15, 31.9%), followed by the ankle/foot (n = 9, 19.1%). The most frequent types of injury were contusion (55.3%), sprain/subluxation (14.9%), and general trauma (10.6%); 74.5% of all injuries resulted from direct impact. Although the competition injury rate for youth flag football was lower than the values from studies reporting comparable tackle football data, the frequencies by body part, type, and mechanism were similar. Given that most injuries were related to some form of impact and predominantly contusions, adopting minimal protective equipment or padding may reduce the numbers of these injuries. [ABSTRACT FROM AUTHOR]

Objectives: Population-level estimates of the median intracerebral hemorrhage (ICH) volume would allow for the evaluation of clinical trial external validity and determination of temporal trends. We previously reported the median ICH volume in 1988. However, differences in risk factor management, neuroimaging, and demographics may have affected ICH volumes. The goal of this study is to determine the median volume of ICH within a population-based cross-sectional study, including whether it has changed over time. Methods: The Genetic and Environmental Risk Factors for Hemorrhagic Stroke study was a population-based study of ICH among residents of the Greater Cincinnati/Northern Kentucky region from 2008 through 2012. This study utilizes those data and compares with ICH cases from the same region in 1988. Initial computed tomography images of the head were reviewed, and ICH volumes were calculated using consistent methodology. Results: From 2008 through 2012, we identified 1117 cases of ICH. The median volume of ICH was 14.0 mL and was lower in black (11.6) than in white (15.5) patients. Median volumes of lobar and deep ICH were 28.8 mL and 9.8 mL, respectively. Median ICH volume changed significantly from 1988 to 2008–2012, with age-and-race-adjusted volume decreasing from 18.3 mL to 13.76 mL (p = 0.025). Conclusions: Median volume of ICH was 13.76 mL, and this should be considered in clinical trial design. Median ICH volume has apparently decreased from 1988 to 2008–2012. [ABSTRACT FROM AUTHOR]

We previously published rates of pediatric stroke using our population-based Greater Cincinnati Northern Kentucky Stroke Study (GCNK) for periods July 1993–June 1994 and 1999. We report population-based rates from 2 additional study periods: 2005 and 2010. We identified all pediatric strokes for residents of the GCNK region that occurred in July 1, 1993–June 30, 1994, and calendar years 1999, 2005, and 2010. Stroke cases were ascertained by screening discharge ICD-9 codes, and verified by a physician. Pediatric stroke was defined as stroke in those <20 years of age. Stroke rates by study period, overall, by age and by race, were calculated. Eleven children died within 30 days, yielding an all-cause case fatality rate of 15.7% (95% confidence interval 1.1%, 26.4%) with 3 (27.3%) ischemic, 6 (54.5%) hemorrhagic, and 2 (18.2%) unknown stroke type. The pediatric stroke rate of 4.4 per 100 000 in the GCNK study region has not changed over 17 years. [ABSTRACT FROM AUTHOR]

Context: An estimated 40 million school-aged children (age range = 5-18 years) participate annually in sports in the United States, generating approximately 4 million sport-related injuries and requiring 2.6 million emergency department visits at a cost of nearly $2 billion. Objective: To determine the effects of a school-based neuromuscular training (NMT) program on sport-related injury incidence across 3 sports at the high school and middle school levels, focusing particularly on knee and ankle injuries. Design: Randomized controlled clinical trial. Setting: A total of 5 middle schools and 4 high schools in a single-county public school district. Patients or Other Participants: A total of 474 girls (222 middle school, 252 high school; age = 14.0 ± 1.7 years, height = 161.0 ± 8.1 cm, mass = 55.4 ± 12.2 kg) were cluster randomized to an NMT (CORE; n = 259 athletes) or sham (SHAM; n = 215 athletes) intervention group by team within each sport (basketball, soccer, and volleyball). Intervention(s): The CORE intervention consisted of exercises focused on the trunk and lower extremity, whereas the SHAM protocol consisted of resisted running using elastic bands. Each intervention was implemented at the start of the season and continued until the last competition. An athletic trainer evaluated athletes weekly for sport-related injuries. The coach recorded each athlete-exposure (AE), which was defined as 1 athlete participating in 1 coach-directed session (game or practice). Main Outcome Measure(s): Injury rates were calculated overall, by sport, and by competition level. We also calculated rates of specific knee and ankle injuries. A mixed-model approach was used to account for multiple injuries per athlete. Results: Overall, the CORE group reported 107 injuries (rate = 5.34 injuries/1000 AEs), and the SHAM group reported 134 injuries (rate = 8.54 injuries/1000 AEs; F1,578 = 18.65, P < .001). Basketball (rate = 4.99 injuries/1000 AEs) and volleyball (rate = 5.74 injuries/1000 AEs) athletes in the CORE group demonstrated lower injury incidences than basketball (rate = 7.72 injuries/1000 AEs) and volleyball (rate = 11.63 injuries/1000 AEs; F1,275 = 9.46, P = .002 and F1,149 = 11.36, P = .001, respectively) athletes in the SHAM group. The CORE intervention appeared to have a greater protective effect on knee injuries at the middle school level (knee-injury incidence rate = 4.16 injuries/1000 AEs) than the SHAM intervention (knee-injury incidence rate = 7.04 injuries/1000 AEs; F1,261 = 5.36, P = .02). We did not observe differences between groups for ankle injuries (F1,578 = 1.02, P = .31). Conclusions: Participation in an NMT intervention program resulted in a reduced injury incidence relative to participation in a SHAM intervention. This protective benefit of NMT was demonstrated at both the high school and middle school levels. [ABSTRACT FROM AUTHOR]

Background: There are several situations in which magnetic resonance imaging (MRI) might impact whether an cerebrovascular event is considered a new stroke. These include clinically non-focal events with positive imaging for acute cerebral infarction, and worsening of older symptoms without evidence of new infarction on MRI. We sought to investigate the impact of MRI on stroke detection and stroke incidence, by describing agreement between a strictly clinical definition of stroke and a definition based on physician opinion, including MRI imaging findings.Methods: All hospitalized strokes that occurred in five Ohio and Northern Kentucky counties (population 1.3 million) in the calendar year of 2005 were identified using ICD-9 discharge codes 430-436. The two definitions used were: "clinical case definition" which included sudden onset focal neurologic symptoms referable to a vascular territory for >24 h, compared to the "best clinical judgment of the physician definition", which considers all relevant information, including neuroimaging findings. The 95% confidence intervals (CI) for the incidence rates were calculated assuming a Poisson distribution. Rates were standardized to the 2000 U.S. population, adjusting for age, race, and sex, and included all age groups.Results: There were 2403 ischemic stroke events in 2269 patients; 1556 (64%) had MRI performed. Of the events, 2049 (83%) were cases by both definitions, 185 (7.7%) met the clinical case definition but were non-cases in the physician's opinion and 169 (7.0%) were non-cases by clinical definition but were cases in the physician's opinion. There was no significant difference in the incidence rates of first-ever or total ischemic strokes generated by the two different definitions, or when only those with MRI imaging were included.Conclusions: We found that MRI findings do not appear to substantially change stroke incidence estimates, as the strictly clinical definition of stroke did not significantly differ from a definition that included imaging findings. Including MRI in the case definition "rules out" almost the same number of strokes as it "rules in". [ABSTRACT FROM AUTHOR]

Aims: Epidemiological studies suggest that sex has a role in the pathogenesis of cardioembolic stroke. Since stroke is a vascular disease, identifying sexually dimorphic gene expression changes in blood leukocytes can inform on sex-specific risk factors, response and outcome biology. We aimed to examine the sexually dimorphic immune response following cardioembolic stroke by studying the differential gene expression in peripheral white blood cells. Methods and Results: Blood samples from patients with cardioembolic stroke were obtained at ≤3 hours (prior to treatment), 5 hours and 24 hours (after treatment) after stroke onset (n = 23; 69 samples) and compared with vascular risk factor controls without symptomatic vascular diseases (n = 23, 23 samples) (ANCOVA, false discovery rate p≤0.05, |fold change| ≥1.2). mRNA levels were measured on whole-genome Affymetrix microarrays. There were more up-regulated than down-regulated genes in both sexes, and females had more differentially expressed genes than males following cardioembolic stroke. Female gene expression was associated with cell death and survival, cell-cell signaling and inflammation. Male gene expression was associated with cellular assembly, organization and compromise. Immune response pathways were over represented at ≤3, 5 and 24 h after stroke in female subjects but only at 24 h in males. Neutrophil-specific genes were differentially expressed at 3, 5 and 24 h in females but only at 5 h and 24 h in males. Conclusions: There are sexually dimorphic immune cell expression profiles following cardioembolic stroke. Future studies are needed to confirm the findings using qRT-PCR in an independent cohort, to determine how they relate to risk and outcome, and to compare to other causes of ischemic stroke. [ABSTRACT FROM AUTHOR]

STUDY DESIGN: Retrospective epidemiologic investigation. OBJECTIVE: To investigate the relationship between altitude and concussion rate in the National Football League (NFL). Because of the physiologic responses that occur during acclimatization to altitude, it was hypothesized that games played on fields at a higher altitude would have reduced concussion rates compared to games played on fields at a lower altitude. BACKGROUND: Recent research indicates that the elevation above sea level at which football games are played may be associated with the likelihood of a concussion in high school football athletes. METHODS: Data on incident concussions and athlete exposures for the first 16 weeks of the NFL 2012 and 2013 regular seasons were obtained from publicly available web-based sources and used to calculate competition concussion rates for each NFL stadium. Concussion rates were analyzed in relation to game elevation. RESULTS: During the first 16 weeks of the 2012 and 2013 NFL regular seasons, 300 concussions, involving 284 players, were reported (64.3 primary cases per 10 000 game exposures). The odds of a concussion were 30% lower when playing at a higher elevation (equal to or greater than 644 ft [196.3 m] above sea level) compared to a lower elevation (odds ratio = 0.70; 95% confidence interval: 0.53, 0.94). A multivariable generalized linear model controlling for season, week, and clustering of team at home and away confirmed these results, showing that the odds of at least 1 concussion were reduced by 32% in games played at higher elevation. CONCLUSION: The results of this epidemiological investigation indicate that increased altitude was associated with a reduction in the odds of a sport-related concussion in NFL athletes. The reported relationship of concussion incidence and field elevation should be further investigated, and, if verified, further work will be needed to understand why that relationship exists. [ABSTRACT FROM AUTHOR]

Background: Population-based studies have estimated that about 15% of ischemic strokes are caused by large-vessel cerebrovascular disease. We determined the types of large-vessel atherosclerosis responsible for ischemic strokes in a population-based stroke study. Methods: Patients with first-ever or recurrent ischemic stroke in the Greater Cincinnati area were identified during 2005 at all local hospitals. Study physicians assigned ischemic stroke subtypes. Overall event rates and incidence rates for first-ever events were calculated, and age-, race- and sex-adjusted to the 2000 US population. Results: There were 2,204 ischemic strokes, including 365 strokes of large-vessel subtype (16.6% of all ischemic strokes). Extracranial internal carotid artery (ICA) stenosis was associated with 8.0% of all ischemic strokes, while extracranial ICA occlusion and intracranial atherosclerosis were each associated with 3.5% of strokes. The annual rate of first-ever and recurrent stroke attributed to extracranial ICA was 13.4 (11.4-15.4) per 100,000 persons. We conservatively estimate that about 41,000 strokes may be attributed to extracranial ICA stenosis annually in the United States. Conclusions: Large-vessel atherosclerosis is an important cause of stroke, with extracranial ICA stenosis being significantly more common than extracranial ICA occlusion or intracranial atherosclerotic disease. [ABSTRACT FROM AUTHOR]

Background: Population-based studies have estimated that about 15% of ischemic strokes are caused by large-vessel cerebrovascular disease. We determined the types of large-vessel atherosclerosis responsible for ischemic strokes in a population-based stroke study. Methods: Patients with first-ever or recurrent ischemic stroke in the Greater Cincinnati area were identified during 2005 at all local hospitals. Study physicians assigned ischemic stroke subtypes. Overall event rates and incidence rates for first-ever events were calculated, and age-, race- and sex-adjusted to the 2000 US population. Results: There were 2,204 ischemic strokes, including 365 strokes of large-vessel subtype (16.6% of all ischemic strokes). Extracranial internal carotid artery (ICA) stenosis was associated with 8.0% of all ischemic strokes, while extracranial ICA occlusion and intracranial atherosclerosis were each associated with 3.5% of strokes. The annual rate of first-ever and recurrent stroke attributed to extracranial ICA was 13.4 (11.4-15.4) per 100,000 persons. We conservatively estimate that about 41,000 strokes may be attributed to extracranial ICA stenosis annually in the United States. Conclusions: Large-vessel atherosclerosis is an important cause of stroke, with extracranial ICA stenosis being significantly more common than extracranial ICA occlusion or intracranial atherosclerotic disease. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Using data from the National Longitudinal Study of Adolescent Health, this study examined the associations among family bonding factors and the initiation of smoking by race/ethnicity and age group among nonsmokers at Wave 1. Overall, 18% of the sample initiated smoking by Wave 2. For younger African-American and Hispanic youths, high maternal satisfaction with the relationship was significantly protective of smoking initiation. For older Hispanics, high parental presence and high parent-family connectedness were protective against smoking initiation, while lack of awareness about the adolescent's whereabouts was a risk factor for initiation in both younger and older Caucasians, and in the older Hispanics. Our results underscore the importance of maintaining high levels of family bonding with the adolescent throughout early and late adolescence in order to decrease tobacco initiation. [ABSTRACT FROM AUTHOR]

We sought to examine neonatal morbidity in four groups of offspring (asymmetric large for gestational age [LGA], symmetric LGA, asymmetric non-LGA, symmetric non-LGA) exposed in utero to maternal type 1 diabetes, and the association between rate of fetal abdominal circumference growth and asymmetric LGA. We performed a secondary analysis of 302 singleton pregnancies. Neonatal morbidity (respiratory distress syndrome, polycythemia, hypoglycemia, hyperbilirubinemia, acidosis, and composite morbidity [any of the five]) was assessed. Serial ultrasound examinations after 20 weeks' gestation were available for 35 fetuses. Logistic regression and general linear mixed modeling were used for analysis. Asymmetric LGA infants had 3.5-, 2.2-, and 3.2-fold greater odds of hypoglycemia, hyperbilirubinemia, and composite morbidity, respectively, compared with symmetric non-LGA infants. The rate of growth of the abdominal circumference in asymmetric LGA infants (1.11 cm/wk) was greater than for both the symmetric LGA infants (0.87 cm/wk, p = 0.09) and the symmetric non-LGA infants (0.87 cm/wk, p = 0.03). Asymmetric LGA infants are at higher risk for morbidity than symmetric LGA and non-LGA infants. Intrauterine growth rate of the abdominal circumference may potentially be used as a marker to identify the asymmetric LGA and thereby aid in the identification of newborns at greatest risk for perinatal complications. [ABSTRACT FROM AUTHOR]

Background: The stroke volume among black ischemic stroke patients in phase I of the population-based Greater Cincinnati/Northern Kentucky Stroke Study (GCNKSS) was smaller than reported among acute stroke studies, with a median stroke volume of 2.5 cm. However, it is not known if stroke volume was similar between black and white patients within the same study population. Methods: Phase II of the GCNKSS identified all ischemic strokes between July 1993 and June 1994. The stroke volume was estimated by study physicians using the modified ellipsoid method. Analysis of stroke volume by race, sex and age was performed for strokes with a measurable lesion of ≥0.5 cm3. Results: Among verified cases of ischemic stroke, 334 patients were eligible for this analysis. There were 191 whites (57%) and 143 blacks (43%). The mean age was 69.4 years. The median stroke volume for all patients was 8.8 cm3 (range 0.5–540), with a mean of 36.4 cm3. Stroke volume was not different between men and women, and it tended to increase with age. Although stroke volume was significantly higher among whites, age was a confounding factor. Subsequent analysis of stroke volume stratified by age showed no difference between blacks and whites in any age group. Conclusions: Our data show that most ischemic stroke lesions, regardless of the race, are of small size, and this may be an important reason for the low percentageof strokes treated currently with tissue-type plasminogen activator. The association of age with stroke volume requires further study. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

We have previously reported that family history of intracerebral hemorrhage (ICH) was associated with both lobar and nonlobar ICH. We sought to further examine this finding by analyzing differences by age and by apolipoprotein E (Apo E) genotype. All cases of hemorrhagic stroke in the greater Cincinnati area were identified through retrospective screening, and a subset was invited to undergo a direct interview and genetic testing. Interviewed subjects were matched to 2 controls by age, race, and sex. Conditional stepwise logistic regression modeling was used to determine whether having a first-degree relative with an ICH (FHICH) was an independent risk factor for ICH. Between May 1997 and December 2002, we recruited 333 cases of ICH. FHICH was found to be an independent risk factor for both lobar ICH (odds ratio [OR] = 3.9; P = .04) and nonlobar ICH (OR ratio = 5.4; P = .01) after controlling for the presence of numerous variables. Among nonlobar ICH cases, the risk appeared to be predominately in those age <70 years. The presence of Apo E4 was associated with lobar ICH at age ≥70 years but not at age <70 years. Family history of ICH appears to be a significant risk factor for nonlobar ICH at age <70 years. The presence of Apo E4 appears to be a risk factor for lobar ICH at age ≥70 years but not at age <70 years. Family history of ICH is a risk factor for lobar ICH after controlling for the presence of Apo E4. [Copyright &y& Elsevier]

OBJECTIVE -- Diabetes is a well known risk factor for stroke, but the impact of diabetes on stroke incidence rates is not known. This study uses a population-based study to describe the epidemiology of ischemic stroke in diabetic patients. RESEARCH DESIGN AND METHODS -- Hospitalized cases were ascertained by ICD-9 discharge codes, prospective screening of emergency department admission logs, and review of coroner's cases. A sampling scheme was used to ascertain cases in the out-of-hospital setting. All potential cases underwent detailed chart abstraction by study nurses followed by physician review. Diabetes-specific incidence rates, case fatality rates, and population-attributable risks were estimated. RESULTS -- Ischemic stroke patients with diabetes are younger, more likely to be African American, and more likely to have hypertension, myocardial infarction, and high cholesterol than nondiabetic patients. Age-specific incidence rates and rate ratios show that diabetes increases ischemic stroke incidence at all ages, but this risk is most prominent before age 55 in African Americans and before age 65 in whites. One-year case fatality rates after ischemic stroke are not different between those patients with and without diabetes. CONCLUSIONS -- Given the "epidemic" of diabetes, with substantially increasing diabetes prevalence each year across all age- and race/ethnicity groups, the significance of diabetes as a risk factor for stroke is becoming more evident. Diabetes is clearly one of the most important risk factors for ischemic stroke, especially in those patients less than 65 years of age. We estimate that 37-42% of all ischemic strokes in both African Americans and whites are attributable to the effects of diabetes alone or in combination with hypertension. [ABSTRACT FROM AUTHOR]