IMPORTANCE Traumatic brain injury (TBI) is the leading cause of death and disability due to trauma. Early administration of tranexamic acid may benefit patients with TBI.OBJECTIVE To determine whether tranexamic acid treatment initiated in the out-of-hospital setting within 2 hours of injury improves neurologic outcome in patients with moderate or severe TBI. DESIGN, SETTING, AND PARTICIPANTS Multicenter, double-blinded, randomized clinical trial at 20 trauma centers and 39 emergency medical services agencies in the US and Canada from May 2015 to November 2017. Eligible participants (N = 1280) included out-of-hospital patients with TBI aged 15 years or older with Glasgow Coma Scale score of 12 or less and systolic blood pressure of 90 mm Hg or higher. INTERVENTIONS Three interventions were evaluated, with treatment initiated within 2 hours of TBI: out-of-hospital tranexamic acid (1 g) bolus and in-hospital tranexamic acid (1 g) 8-hour infusion (bolus maintenance group; n = 312), out-of-hospital tranexamic acid (2 g) bolus and in-hospital placebo 8-hour infusion (bolus only group; n = 345), and out-of-hospital placebo bolus and in-hospital placebo 8-hour infusion (placebo group; n = 309). MAIN OUTCOMES AND MEASURESThe primary outcome was favorable neurologic function at 6 months (Glasgow Outcome Scale-Extended score >4 [moderate disability or good recovery]) in the combined tranexamic acid group vs the placebo group. Asymmetric significance thresholds were set at 0.1 for benefit and 0.025 for harm. There were 18 secondary end points, of which 5 are reported in this article: 28-day mortality, 6-month Disability Rating Scale score (range, 0 [no disability] to 30 [death]), progression of intracranial hemorrhage, incidence of seizures, and incidence of thromboembolic events. RESULTS Among 1063 participants, a study drug was not administered to 96 randomized participants and 1 participant was excluded, resulting in 966 participants in the analysis population (mean age, 42 years; 255 [74%] male participants; mean Glasgow Coma Scale score, 8). Of these participants, 819 (84.8%) were available for primary outcome analysis at 6-month followup. The primary outcome occurred in 65% of patients in the tranexamic acid groups vs 62% in the placebo group (difference, 3.5%; [90% 1-sided confidence limit for benefit, −0.9%]; P = .16; [97.5% 1-sided confidence limit for harm, 10.2%]; P = .84). There was no statistically significant difference in 28-day mortality between the tranexamic acid groups vs the placebo group (14% vs 17%; difference, −2.9% [95% CI, −7.9% to 2.1%]; P = .26), 6-month Disability Rating Scale score (6.8 vs 7.6; difference, −0.9 [95% CI, −2.5 to 0.7]; P = .29), or progression of intracranial hemorrhage (16% vs 20%; difference, −5.4% [95% CI, −12.8% to 2.1%]; P = .16).CONCLUSIONS AND RELEVANCE Among patients with moderate to severe TBI, out-of-hospital tranexamic acid administration within 2 hours of injury compared with placebo did not significantly improve 6-month neurologic outcome as measured by the Glasgow Ou...

Local area community cumulative incidence (per 1,000 population) Health care personnel with positive test results for SARS-CoV-2 antibodies (%) Abbreviation: COVID-19 = coronavirus disease 2019. * Calculated as the total number of reported community COVID-19 cases within a hospital-area county or counties between the beginning of the pandemic and 7 days after the first day of health care personnel enrollment at the hospital divided by population of the county or counties x 1,000.

Much has been learned about the pathophysiology of narcolepsy over the last several decades. It is likely that hypocretin-producing cells in the lateral hypothalamus are selectively destroyed in genetically susceptible individuals carrying 1 or more alleles of HLA DQB1*0602. Despite advances, the causes of narcolepsy and how to prevent it remain elusive. Classic epidemiology aims not only to enumerate occurrence of disease in populations, but also to identify etiologic risk factors. This review details what the application of classic epidemiology has taught us so far about narcolepsy and suggests directions for future studies to clarify its etiology. The prevalence of narcolepsy with cataplexy has been examined in many studies and falls between 25 and 50 per 100,000 people. Information on incidence is limited, with 1 study finding the incidence of narcolepsy with cataplexy to be 0.74 per 100,000 person-years. The search for etiologic risk factors has yet to yield important associations. Factors most thoroughly examined include body mass index, immune responses, and stressful life events. Such associations may reflect a consequence rather than a cause of disease. As with other diseases characterized by selective cell loss, such as Parkinson disease or type 1 diabetes mellitus, narcolepsy is likely caused by environmental exposures before the age of onset in genetically susceptible individuals. Matching efforts in these other diseases and using large well-designed epidemiologic studies of narcolepsy, investigators must intensify the search for these exposures, focusing on the first 2 decades of life. Identification of modifiable risk factors will help to prevent this disease.

this report was posted as an MMWR Early Release on the MMWR website (https://www.cdc.gov/mmwr).Adults aged ≥65 years are at increased risk for severe outcomes from COVID-19 and were identified as a priority group to receive the first COVID-19 vaccines approved for use under an Emergency Use Authorization (EUA) in the United States (1-3). In an evaluation at 24 hospitals in 14 states,* the effectiveness of partial or full vaccination † with Pfizer-BioNTech or Moderna vaccines against COVID-19-associated hospitalization was assessed among adults aged ≥65 years. Among 417 hospitalized adults aged ≥65 years (including 187 case-patients and 230 controls), the median age was 73 years, 48% were female, 73% were non-Hispanic White, 17% were non-Hispanic Black, 6% were Hispanic, and 4% lived in a long-term care facility. Adjusted vaccine effectiveness (VE) against COVID-19-associated hospitalization among adults aged ≥65 years was estimated to be 94% (95% confidence interval [CI] = 49%-99%) for full vaccination and 64% (95% CI = 28%-82%) for partial vaccination. These findings are consistent with efficacy determined from clinical trials in the subgroup of adults aged ≥65 years (4,5). This multisite U.S. evaluation under real-world conditions suggests that vaccination provided protection against COVID-19-associated hospitalization among adults aged * Patients were enrolled from 24 medical centers in 14 states (

Even moderate changes in prepregnancy weight can apparently affect the risk of gestational diabetes among obese women. This may offer further motivation for interventions aimed at reducing obesity among women of reproductive age.