High altitude modulates concussion incidence, severity, and recovery in young athletes.

BACKGROUND: High altitude may affect concussion, but prior studies are limited . We tested whether high altitude affects sport-related concussion (SRC) incidence, severity, and recovery. METHODS: Twenty-five thousand eight hundred fifteen baseline and post-injury Immediate Post-Concussion Assessment and Cognitive Testing results were compiled from Florida and Colorado, low (27 m or 62 m) and high (1,640 m or 1,991 m) altitude locations, respectively. Incidence, severity, and recovery of injury were compared between altitudes. RESULTS: High altitude was associated with increased suspected concussion incidence (adjusted OR, 2.04 [95% CI, 1.86 to 2.24];P < .0001). However, high altitude was associated with lower concussion severity measured by Severity Index (SI) (adjusted OR, 0.42 [95% CI, 0.37 to 0.49];P < .0001). High altitude was associated with decreased recovery from post-concussive symptoms in the migraine (ß, -2.72 [95% CI, -3.31 to -2.13]; P < .0001), cognitive (ß, -1.88 [95% CI, -2.40 to -1.36]; P < .0001), and sleep symptom clusters (ß, -0.30 [95% CI, -0.52 to -0.08]; P = .007). Athletes with initial SI≥8 showed prolonged neurocognitive dysfunction at high altitude (HR, 1.38 [95% CI, 1.06 to 1.81]; P = .02). CONCLUSIONS: High altitude was associated with increased suspected concussions and prolonged recovery but less severe initial injury.

A Multivariable Analysis to Evaluate the Presence or Absence of Gender Differences in Baseline ImPACT Composite Scores and Symptom Severity Ratings in Student-Athletes Ages 12-18 Years.

INTRODUCTION: Gender differences in neurocognitive function have been reported over the past few decades. However, multiple studies that report gender differences in Immediate Post-Concussion Assessment and Cognitive Tests composite scores ignore potential confounders which may lead to inaccurate results. METHODS: A total of 4829 male and 2477 female baseline Immediate Post-Concussion Assessment and Cognitive Tests from 2009 to 2019 of subjects ages 12-18 years were used to evaluate gender differences in baseline neurocognitive scores and symptom severity ratings. Regression analyses were used to assess the effects of gender on neurocognitive performance at baseline while controlling for a number of potential confounders including symptom burden at the time of testing. RESULTS: Differences in 3 of 5 composite scores as well as severity rating scores were maintained in multivariate analysis. Females had increased Post-Concussion Symptom Scale (ß = 3.54, 95% confidence interval, 2.91 to 4.16, P < .0001) along with higher verbal memory (ß = 1.82, 95% confidence interval, 1.15 to 2.50, P < .0001) and visual motor (ß = 1.29, 95% confidence interval, 0.85-1.72, P < .0001) scores. CONCLUSIONS: Statistically significant gender differences were found in baseline neurocognitive function. This study clarifies for the first time that gender differences in these neurocognitive domains are not simply an artifact of differences in symptom burden. However, the small effect sizes call into question the clinical relevance of these differences.

Telehealth treatment for nonspecific low back pain: A review of the current state in mobile health.

INTRODUCTION: Nonspecific low back pain (LBP) is an idiopathic musculoskeletal condition that affects four of five individuals in their lifetime and is the leading cause of job-related disability in the United States. The interest in interactive and dynamic telehealth treatments for LBP continues to grow, and it is important for the medical community to remain up-to-date on the state of the science. LITERATURE SURVEY: Relevant studies published from March 2016 until March 2021 were identified through a systematic search of EMBASE, MedLine, and Web of Science. The search strategy combined the concepts of back pain, telehealth, and mobile applications. METHODOLOGY: Titles and abstracts were screened to select full-text randomized controlled trials or protocols, and methodological quality and risk of bias was assessed using the Cochrane risk-of-bias tool. Data were synthesized narratively. SYNTHESIS: We included seven concluded randomized-controlled trials and two study protocols reporting mobile health (mHealth) solutions for LBP. Six of the seven concluded trials found a significant improvement in self-reported numerical pain rating scale compared to the control group. A single trial compared a mHealth solution to physical therapy, with the majority of studies comparing interventions to "usual care." Substantial heterogeneity in reporting of sample characteristics was found, indicating a lack of standardization through the field. CONCLUSIONS: mHealth solutions may positively impact people with LBP. Larger trials should be encouraged and the field should coalesce around a set of baseline variables for collection and reporting. Because many interventions involve patient engagement, future trials should aim to further quantify adherence levels and begin to define telehealth "doses" associated with better outcomes.

Bibliometric Evaluation of U.S. Neurosurgery Subspecialties and Academic Rank Using RCR Index.

INTRODUCTION: Academic productivity, a key feature of academic neurosurgery, has been linked to academic rank, subspecialty, and institutional rank. Relative Citation Ratio (RCR) has emerged as a new metric of scholarly output that can make field-normalized comparisons between researchers, a feature unavailable in prior metrics such as h-index. Here we evaluate the influence of academic rank and neurosurgical subspecialties on RCR scores. METHODS: We identified 1640 academic neurosurgeons from 115 ACGME-accredited programs in the United States, along with their neurosurgical specialty and demographic information, using publicly available data. Mean RCR (m-RCR) and weighted RCR (w-RCR) for each neurosurgeon were queried from the iCite database, which included publications from 2002-2020. m-RCR and w-RCR scores were compared across subspecialties and academic rank using multivariable regression while controlling for demographic factors. RESULTS: Multivariable analysis indicated that academic neurosurgeons in general neurosurgery (P = 0.039) and pediatric neurosurgery (P = 0.003) had lower m-RCR scores than their peers in other subspecialties. w-RCR did not differ significantly among subspecialties. Higher academic rank was associated with increased m-RCR (P < 0.05) and w-RCR scores (P < 0.0001). CONCLUSIONS: Professors have a higher m-RCR score relative to assistant professors, while general and pediatric neurosurgery were linked to lower m-RCR values. Although neurosurgical subspecialty choice did not influence w-RCR, a higher w-RCR score corresponded to a higher academic rank. Overall, the RCR metric can be utilized for field-normalized comparisons of faculty who differ in academic rank and subspecialty.

Sport Contact Level Affects Post-Concussion Neurocognitive Performance in Young Athletes.

OBJECTIVE: Contact level affects the incidence of sports-related concussion. However, the effects of contact level on injury severity and recovery are less clear and are the focus of this study. METHOD: Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) for athletes aged 12-22 was performed at baseline (n = 10,907 for 7,058 athletes), after suspected concussion determined by physicians or athletic trainers (n = 5,062 for 4,419 athletes), and during follow-up visits (n = 3,264 for 2,098 athletes). Athletes played contact/collision (CC), limited contact (LC), and noncontact (NC) sports. Injury incidence, severity, and recovery were measured using raw and change from baseline neurocognitive test scores. Comparisons between groups used univariate analysis and multivariable regression controlling for demographic variables. RESULTS: Compared to CC athletes, LC and NC athletes showed decreased suspected concussion incidence. At initial post-injury testing, all neurocognitive test scores were similar between groups except changes from baseline for processing speed were improved for LC compared to CC athletes. Upon follow-up testing, raw neurocognitive scores were better for NC compared to the contact collision athletes in verbal memory, processing speed, total symptom score, migraine cluster, cognitive cluster, and neuropsychiatric cluster scores. For change from baseline scores, LC athletes exhibited better performance on verbal memory, processing speed, and reaction time but also showed higher neuropsychiatric scores than CC athletes. CONCLUSION: Neurocognitive scores between contact levels were similar at the first post-injury test. However, follow up showed many improved scores and symptoms for limited and NC sports compared to CC sports, which may indicate faster recovery.

Incidence and Severity of Concussions Among Young Soccer Players Based on Age, Sex, and Player Position.

BACKGROUND: Previously studied risk factors for sports-related concussion in soccer players include sex, age, and player position. However, prior studies were limited in number, they reported conflicting results, and most did not assess initial concussion severity. PURPOSE/HYPOTHESIS: The purpose of this study was to conduct an in-depth analysis of soccer players across key demographic groups (sex, age, position) for both concussion incidence and severity. It was hypothesized that concussion incidence and severity would be higher among male players, players aged ≥17 years, and goalkeepers. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: The authors analyzed baseline and postinjury ImPACT (Immediate Post-Concussion Assessment and Cognitive Testing) scores for athletes aged 12 to 22 years between July 2009 and June 2019. Players were assigned to an age group based on when they had their most recent baseline test. Concussion incidence and concussion severity index were compared using t tests and multivariate logistic regression. RESULTS: For 1189 individuals who reported soccer as their primary sport, 1032 contributed 1754 baseline ImPACT tests (some individuals had multiple baseline tests), whereas 445 individuals were suspected of sustaining a concussion and then referred for a postinjury 1 test. Of these players, 254 (24.6%) had both a baseline and a postinjury test and were analyzed for concussion severity. Linear regression showed that forwards had a lower incidence of ImPACT-proxied concussions than goalkeepers had (P = .008). Female players had a significantly higher incidence of ImPACT concussions compared with male players (mean, 0.07 [female] vs 0.04 [male] concussions per person-year; P = .05). Players in the ≥17-year age group had a higher incidence of ImPACT concussions than players in the 15- to 16-year age group (P = .04), although the 15- to 16-year age group had more severe concussions than the ≥17-year age group (mean severity index, 2.91 [age 15-16 years] vs 1.73 [age ≥17 years]; P = .001). CONCLUSION: Female soccer players experienced a higher incidence of concussion than did male players, and goalkeepers experienced a greater incidence of ImPACT concussions than did forwards. Players of both sexes and all positions in the 15- to 16-year age group showed increased initial concussion severity compared with the ≥17-year age group, despite a lower comparative incidence of ImPACT concussions. Further study is needed to understand whether sex and player position affect concussion severity.

Policy Interventions, Social Distancing, and SARS-CoV-2 Transmission in the United States: A Retrospective State-level Analysis.

BACKGROUND: Various non-pharmaceutical interventions (NPIs) such as stay-at-home orders and school closures have been employed to limit the spread of Coronavirus disease (COVID-19). This study measures the impact of social distancing policies on COVID-19 transmission in US states during the early outbreak phase to assess which policies were most effective. METHODS: To measure transmissibility, we analyze the average effective reproductive number (Rt) in each state the week following its 500th case and doubling time from 500 to 1000 cases. Linear and logistic regressions were performed to assess the impact of various NPIs while controlling for population density, GDP, and certain health metrics. This analysis was repeated for deaths with doubling time to 100 deaths with several healthcare infrastructure control variables. RESULTS: States with stay-at-home orders in place at the time of their 500th case were associated with lower average Rt the following week compared to states without them (p<0.001) and significantly less likely to have an Rt>1 (OR 0.07, 95% CI 0.01-0.37, p = 0.004). These states also experienced longer doubling time from 500 to 1000 cases (HR 0.35, 95% CI 0.17-0.72, p = 0.004). States in the highest quartile of average time spent at home were also slower to reach 1000 cases than those in the lowest quartile (HR 0.18, 95% CI 0.06-0.53, p = 0.002). CONCLUSIONS: Stay-at-home orders had the largest effect of any policy analyzed. Multivariate analyses with cellphone tracking data suggest social distancing adherence drives these effects. States that plan to scale back such measures should carefully monitor transmission metrics.

Academic Productivity of United States Neurosurgeons Trained Abroad.

BACKGROUND: Previous research in neurosurgery has examined academic productivity for U.S. medical graduates and residents. However, associations between scholarly output and international medical education, residency training, and fellowship training are scarcely documented. METHODS: We identified 1671 U.S. academic neurosurgeons in 2020 using publicly available data along with their countries of medical school, residency, and fellowship training. Using Scopus, h-index, number of publications, and number of times publications were cited were compiled. Demographic, subspeciality, and academic productivity variables were compared between training locations using univariate analysis and multivariable linear regression. RESULTS: Of the current neurosurgery faculty workforce, 16% completed at least 1 component of their training abroad. Canada was the most represented international country in the cohort. Academic productivity for neurosurgeons with international medical school and/or international residency did not significantly differ from that of neurosurgeons trained in the United States. Neurosurgeons with ≥1 U.S. fellowships or ≥1 international fellowships did not have higher academic productivity than neurosurgeons without a fellowship. However, dual fellowship training in both domestic and international programs was associated with higher mean h-index (ß = 6.00, 95% confidence interval 1.01 to 10.98, P = 0.02), higher citations (ß = 2092.0, 95% confidence interval 460.1 to 3724.0, P = 0.01), and a trend toward higher publications (ß = 36.82, 95% confidence interval -0.21 to 73.85, P = 0.051). CONCLUSIONS: Neurosurgeon scholarly output was not significantly affected by international training in medical school or residency. Dual fellowship training in both a domestic and an international program was associated with higher academic productivity.

Sex-Related Differences in the Incidence, Severity, and Recovery of Concussion in Adolescent Student-Athletes Between 2009 and 2019.

BACKGROUND: The sex of an athlete is thought to modulate concussion incidence; however, the effects of sex on concussion severity and recovery are less clear. PURPOSE: To evaluate sex differences in concussion severity and recovery using a large, heterogeneous sample of young student-athletes with the goal of understanding how sex affects concussion outcomes in young athletes. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: The Immediate Post-Concussion Assessment and Cognitive Testing results of 11,563 baseline and 5216 postinjury tests were used to calculate the incidence of concussion of adolescent male and female student-athletes ages 12 to 22 years (median, 15 years). The postinjury tests of 3465 male and 1751 female student-athletes evaluated for concussion or head trauma were used to assess differences in the Severity Index (SI) and recovery. Chi-square tests and t tests were used to compare differences in demographic characteristics, incidence, and SI between the 2 cohorts. Multivariable linear, logistic, and Cox proportional hazards regressions were used to control for differences between cohorts in analyses of incidence, SI, and recovery. RESULTS: When we controlled for demographic differences, female participants had higher odds of concussion (odds ratio, 1.62; 95% CI, 1.40-1.86; P < .0001) and higher SI after concussion (ß = 0.67; 95% CI, 0.02-1.32; P = .04). This discrepancy in SI was a result of differences in Symptom (2.40 vs 2.94; P < .0001) and Processing Speed (0.91 vs 1.06; P = .01) composite scores between male and female participants, respectively. We found no effect of sex on time to recovery when controlling for initial concussion SI (hazard ratio, 0.94; 95% CI, 0.78-1.12; P = .48). CONCLUSION: Using large, multisport cohorts, this study provides evidence that female athletes are at higher risk for more concussions and these concussions are more severe, but male and female athletes have similar recovery times when the analysis controls for initial concussion SI.

Multivariate Analysis of Black Race and Environmental Temperature on COVID-19 in the US.

BACKGROUND: There has been much interest in environmental temperature and race as modulators of Coronavirus disease-19 (COVID-19) infection and mortality. However, in the United States race and temperature correlate with various other social determinants of health, comorbidities, and environmental influences that could be responsible for noted effects. This study investigates the independent effects of race and environmental temperature on COVID-19 incidence and mortality in United States counties. METHODS: Data on COVID-19 and risk factors in all United States counties was collected. 661 counties with at least 50 COVID-19 cases and 217 with at least 10 deaths were included in analyses. Upper and lower quartiles for cases/100,000 people and halves for deaths/100,000 people were compared with t-tests. Adjusted linear and logistic regression analyses were performed to evaluate the independent effects of race and environmental temperature. RESULTS: Multivariate regression analyses demonstrated Black race is a risk factor for increased COVID-19 cases (OR=1.22, 95% CI: 1.09-1.40, P=0.001) and deaths independent of comorbidities, poverty, access to health care, and other risk factors. Higher environmental temperature independently reduced caseload (OR=0.81, 95% CI: 0.71-0.91, P=0.0009), but not deaths. CONCLUSIONS: Higher environmental temperatures correlated with reduced COVID-19 cases, but this benefit does not yet appear in mortality models. Black race was an independent risk factor for increased COVID-19 cases and deaths. Thus, many proposed mechanisms through which Black race might increase risk for COVID-19, such as socioeconomic and healthcare-related predispositions, are inadequate in explaining the full magnitude of this health disparity.