Faculty Bibliography

BACKGROUND: New York City (NYC) has made significant roadway infrastructure improvements, initiated a bicycle share program, and enacted Vision Zero, an action plan to reduce traffic deaths and serious injuries. The objective of this study was to examine whether bicycle helmets offer a protective advantage against traumatic brain injury (TBI) within a contemporary dense urban setting with a commitment to road safety. METHODS: A prospective observational study of injured bicyclists presenting to a Level I trauma centre was performed. All bicyclists arriving within 24h of injury were included. Data were collected between February, 2012 and August, 2014 and included demographics, imaging studies (e.g. computed tomography (CT)), injury patterns, and outcomes including Glasgow Coma Scale (GCS) and Injury Severity Score. RESULTS: Of 699 patients, 273 (39.1%) were wearing helmets at the time of injury. Helmeted bicyclists were more likely to have a GCS of 15 (96.3% [95% Confidence Interval (CI), 93.3-98.2] vs. 87.6 [95% CI, 84.1-90.6]) at presentation. Helmeted bicyclists underwent fewer head CTs (40.3% [95% CI, 34.4-46.4] vs. 52.8% [95% CI, 48.0-57.6]) and were less likely to sustain intracranial injury (6.3% [95% CI, 2.6-12.5] vs. 19.7% [14.7-25.6]), including skull fracture (0.9% [95% CI, 0.0-4.9] vs. 15.3% [95% CI, 10.8-20.7]) and subdural hematoma (0.0% [95% CI, 0.0-3.2] vs. 8.1% [95% CI, 4.9-12.5]). Helmeted bicyclists were significantly less likely to sustain significant TBI, i.e. Head AIS >/=3 (2.6% [95% CI: 0.7-4.5] vs.10.6% [7.6-12.5]). Four patients underwent craniotomy while three died; all were un-helmeted. A multivariable logistic regression model showed that helmeted bicyclists were 72% less likely to sustain TBI compared with un-helmeted bicyclists (Adjusted Odds Ratio 0.28, 95% CI 0.12-0.61). CONCLUSIONS: Despite substantial road safety measures in NYC, the protective impact of simple bicycle helmets in the event of a crash remains significant. A re-assessment of helmet laws for urban bicyclists is advisable to most effectively translate Vision Zero from a political action plan to public safety reality.

Study Objectives: New York City (NYC) recently expanded its bicycle routes by demarcating bike lanes with paint and constructing 30 miles of protected paths that physically separate automobile traffic from bicyclists to address increases in bicyclist fatalities. Our objective was to determine whether bike lanes and protected paths result in safety benefits for bicyclists in NYC. We hypothesized that bike lanes would be associated with reduced injury severity among bicyclists colliding with motor vehicles and that protected paths would be associated with an even greater safety benefit. Methods: We performed a secondary analysis of bicyclist injury data collected from December 2008 to August 2014 at a Level 1 Trauma Center in NYC. We evaluated the association of protected paths and bike lanes on injury severity while controlling for potential confounders including patient demographics, scene-related and environmental information, helmet use, traffic law compliance, street characteristics, and injury mechanism. Data were obtained from patient interviews and medical records. Injury severity score (ISS) was categorized according to National Trauma Data Bank (NT

OBJECTIVES: We determined the demographic characteristics, behaviors, injuries, and outcomes of commercial bicyclists who were injured while navigating New York City's (NYC's) central business district. METHODS: Our study involved a secondary analysis of prospectively collected data from a level 1 regional trauma center in 2008 to 2014 of bicyclists struck by motor vehicles. We performed univariable and multivariable logistic regression analyses. RESULTS: Of 819 injured bicyclists, 284 (34.7%) were working. Commercial bicyclists included 24.4% to 45.1% of injured bicyclists annually. Injured commercial bicyclists were more likely Latino (56.7%; 95% confidence interval [CI] = 50.7, 62.8 vs 22.7%; 95% CI = 19.2, 26.5). Commercial bicyclists were less likely to be distracted by electronic devices (5.0%; 95% CI = 2.7, 8.2 vs 12.7%; 95% CI = 9.9, 15.9) or to have consumed alcohol (0.7%; 95% CI = 0.9, 2.5 vs 9.5%; 95% CI = 7.2, 12.3). Commercial and noncommercial bicyclists did not differ in helmet use (38.4%; 95% CI = 32.7, 44.4 vs 30.8%; 95% CI = 26.9, 34.9). Injury severity scores were less severe in commercial bicyclists (odds ratio = 0.412; 95% CI = 0.235, 0.723). CONCLUSIONS: Commercial bicyclists represent a unique cohort of vulnerable roadway users. In NYC, minorities, especially Latinos, should be targeted for safety education programs. (Am J Public Health. Published online ahead of print August 13, 2015: e1-e6. doi:10.2105/AJPH.2015.302738).

OBJECTIVES: We sought to improve public health surveillance by using a geographic analysis of emergency department (ED) visits to determine local chronic disease prevalence. METHODS: Using an all-payer administrative database, we determined the proportion of unique ED patients with diabetes, hypertension, or asthma. We compared these rates to those determined by the New York City Community Health Survey. For diabetes prevalence, we also analyzed the fidelity of longitudinal estimates using logistic regression and determined disease burden within census tracts using geocoded addresses. RESULTS: We identified 4.4 million unique New York City adults visiting an ED between 2009 and 2012. When we compared our emergency sample to survey data, rates of neighborhood diabetes, hypertension, and asthma prevalence were similar (correlation coefficient = 0.86, 0.88, and 0.77, respectively). In addition, our method demonstrated less year-to-year scatter and identified significant variation of disease burden within neighborhoods among census tracts. CONCLUSIONS: Our method for determining chronic disease prevalence correlates with a validated health survey and may have higher reliability over time and greater granularity at a local level. Our findings can improve public health surveillance by identifying local variation of disease prevalence. (Am J Public Health. Published online ahead of print July 16, 2015: e1-e8. doi:10.2105/AJPH.2015.302679).

Background: Mild traumatic brain injuries are frequently evaluated in EDs. Standardized concussion surveillance tools such as the SCAT 3 have been proposed. Developed as a post-injury tool for athletes, SCAT3 is routinely used in pre-injury, baseline assessment. Population-based normative data can aid in interpretation of individual variability or when baseline data are unavailable. To date, all SCAT3 data have been collected in the athlete population with an absence of data on non-athlete (N-A) controls or acutely injured nonathletes. Objectives: We investigate SCAT3 subcomponents in N-A healthy controls, corpus (non head-injured) trauma, and acutely head-injured patients presenting to the ED to derive reference values for novel populations. We hypothesize that trauma patients with suspected head injury will have worse SCAT3 metrics than uninjured controls. Methods: Target groups were extracted from a database of prospectively recruited patients. SCAT3/SAC (Standardized Assessment of Concussion) was administered at time of ED presentation or recruitment. Multi-sample comparisons were evaluated by the Kruskal- Wallis test; pairwise comparisons were analyzed by the Steel-Dwass procedure. Results: A comparison of SCAT3 subcomponents by patient group is seen in Table 732a. One hundred eleven N-A healthy controls, 121 bodily trauma not warranting head CT in ED, 242 head trauma with negative head CT findings, and 67 head trauma patients with positive head CT were evaluated. Control group comparison seen in Table 732b. In number of symptoms, symptom severity score, and SAC, there was a significant difference between control, corpus and - CT/+CT groups. In immediate memory and Balance Error Scoring System (BESS), there was a significant difference between control, corpus, and -CT/+CT, with corpus statistically similar to -CT/ +CT. In concentration, there was a significant difference between control, corpus, and -CT/+CT, with corpus similar to -CT. In orientation, there was a significant difference between control/corpus and -CT/+CT. Conclusion: In healthy, N-A controls, all SCAT3 values were significantly different from all trauma groups'. In -CT/+CT groups, all SCAT3 values were similar to each other. A graded effect was seen from control to corpus to head trauma. Diagnostic ranges of SCAT3 subcomponents vary in the N-A and bodily trauma population. (Table presented)

Introduction: Disconjugate eye movements have been associated with traumatic brain injury since ancient times. Ocular motility dysfunction may be present in up to 90% of patients with concussion or blast injury. Methods: We developed an algorithm for eye tracking in which the Cartesian coordinates of the right and left pupils are tracked over 200 seconds and compared to each other as a subject watches a short film clip moving inside an aperture on a computer screen. We prospectively eye tracked 64 normal healthy non-injured control subjects and compared findings to 75 trauma subjects with either a positive head CT (n=13), negative head CT (n=39) or non-head injury (n=23) to determine whether eye tracking would reveal the disconjugate gaze associated with both structural brain injury and concussion. Tracking metrics were then correlated to the clinical concussion measure SCAT3 in trauma patients. Results: Five out of five measures of horizontal disconjugacy were increased in positive and negative head CT patients relative to non-injured control subjects. Only one of five vertical disconjugacy measures was significantly increased in brain injured patients relative to controls. Linear regression analysis of all 75 trauma patients demonstrated that three metrics for horizontal disconjugacy negatively correlated with SCAT3 symptom severity score and positively correlated with total Standardized Assessment of Concussion (SAC) score. Abnormal eye tracking metrics improved over time towards baseline in brain injured subjects seen in follow-up. Conclusions: Eye tracking may help quantify the severity of ocular motility disruption associated with concussion and structural brain injury.

Objectives To examine patients' reasons for using the emergency department (ED) for low-acuity health complaints, and determine whether reasons differed for frequent ED users versus nonfrequent ED users. Study Design Prospective cross-sectional survey. Methods Patients presenting to an urban public hospital for low-acuity health complaints were surveyed about their reasons for visiting the ED rather than a private doctor's office or clinic. Patients with 3 or more visits to the study hospital ED over the past year were classified as frequent ED users. Multivariable logistic regression was used to determine if frequent ED users gave different reasons for ED use than nonfrequent ED users, while controlling for differences in other baseline patient characteristics. Results 940 patients, including 163 frequent ED users, completed the study questionnaire. Commonly cited reasons for using the ED were that coming to the ED was easier than making a clinic appointment (82.3% agreed); the problem could not wait (78.8%); they didn't know how to make a clinic appointment (66.7%); they felt the ED provided better care (56.7%); and they believed the clinic would cost more (54.8%). After controlling for other patient characteristics, there were no significant differences found in reasons for ED use given by frequent versus nonfrequent ED users. Conclusions Frequent ED users gave similar reasons for using the ED for low-acuity health complaints compared with nonfrequent ED users. Access, convenience, cost, and quality concerns, as well as feeling that ED care was needed, were all commonly cited as reasons for using the ED.