Likang Xu’s research while affiliated with Centers for Disease Control and Prevention and other places

Objective: Traumatic brain injury (TBI) can result in new onset of comorbidities and limited studies suggest health care utilization following TBI may be high. Setting, Participants, Mean Measures, and Design: This study used 2018 and 2019 MarketScan Commercial Claims and Encounters data to examine differences in longitudinal health outcomes (health care utilization and new diagnoses) by various demographic factors (age, sex, U.S. region, intent/mechanism of injury, urbanicity, and insurance status) among individuals with and without a TBI in the year following an index health care encounter. Results: Results show that within 1 year of the initial encounter, a higher percentage of patients with TBI versus without TBI had at least one outpatient visit (96.7% vs 86.1%), emergency department (ED) visit (28.5% vs 13.1%), or hospital admission (6.4% vs 2.6%). Both children (33.8% vs 23.4%) and adults (43.8% vs 31.4%) who sustained a TBI had a higher percentage of new diagnoses within 1 year compared to the non-TBI group. Additionally, individuals with a TBI had greater health care utilization across all types of health care settings (outpatient and inpatient), visits (ED visits and hospital admissions), and across all demographic factors (P < .001). Conclusion: These results may inform future research around the development of systems of care to improve longer-term outcomes in individuals with TBI.

Objective Injuries and poisoning are leading causes of US morbidity and mortality. This study aimed to update medical and work loss cost estimates per injured person. Methods Injuries treated in emergency departments (ED) during 2019–2020 were analysed in terms of mechanism (eg, fall) and intent (eg, unintentional), as well as traumatic brain injury (TBI) (multiple mechanisms and intents). Fatal injury medical spending was based on the Nationwide Emergency Department Sample and National Inpatient Sample. Non-fatal injury medical spending and workplace absences (general, short-term disability and workers’ compensation) were analysed among injury patients with commercial insurance or Medicaid and matched controls during the year following an injury ED visit using MarketScan databases. Results Medical spending for injury deaths in hospital EDs and inpatient settings averaged US$4777 (n=57 296) and US$45 678 per fatality (n=89 175) (2020 USD). Estimates for fatal TBI were US$5052 (n=5363) and US$47 952 (n=37 184). People with ED treat and release visits for non-fatal injuries had on average US$5798 (n=895 918) in attributable medical spending and US$1686 (11 missed days) (n=116 836) in work loss costs during the following year, while people with non-fatal injuries who required hospitalisation after an ED injury visit had US$52 246 (n=32 976) in medical spending and US$7815 (51 days) (n=4473) in work loss costs. Estimates for non-fatal TBI were US$4529 (n=25 792), US$1503 (10 days) (n=1631), US$51 241 (n=3030) and US$6110 (40 days) (n=246). Conclusions and relevance Per person costs of injuries and violence are important to monitor the economic burden of injuries and assess the value of prevention strategies.

Background: Syringe services programs (SSPs) are community-based prevention programs that provide a range of harm reduction services to persons who inject drugs. Despite their benefits, SSP laws vary across the United States. Little is known regarding how legislation surrounding SSPs may have influenced HIV transmission over the COVID-19 pandemic, a period in which drug use increased. This study examined associations between state SSP laws and HIV transmission among the Medicaid population before and after the COVID-19 pandemic. Methods: State-by-month counts of new HIV diagnoses among the Medicaid population were produced using administrative claims data from the Transformed Medicaid Statistical Information System from 2019 to 2020. Data on SSP laws were collected from the Prescription Drug Abuse Policy System. Associations between state SSP laws and HIV transmission before and after the start of the COVID-19 pandemic were evaluated using an event study design, controlling for the implementation of COVID-19 nonpharmaceutical interventions and state and time fixed effects. Results: State laws allowing the operation of SSPs were associated with 0.54 (P = 0.044) to 1.18 (P = 0.001) fewer new monthly HIV diagnoses per 100,000 Medicaid enrollees relative to states without such laws in place during the 9 months after the start of the COVID-19 pandemic. The largest effects manifested for population subgroups disproportionately affected by HIV, such as male and non-Hispanic Black Medicaid enrollees. Conclusion: Less restrictive laws on SSPs may have helped mitigate HIV transmission among the Medicaid population throughout the COVID-19 pandemic. Policymakers can consider implementing less restrictive SSP laws to mitigate HIV transmission resulting from future increases in injection drug use. Disclaimer: The findings and conclusions in this report are those of the author(s) and do not necessarily represent the official position of the Centers for Disease Control and Prevention.

Background Current methods of traumatic brain injury (TBI) morbidity surveillance in the United States have primarily relied on hospital-based data sets. However, these methods undercount TBIs as they do not include TBIs seen in outpatient settings and those that are untreated and undiagnosed. A 2014 National Academy of Science Engineering and Medicine report recommended that the Centers for Disease Control and Prevention (CDC) establish and manage a national surveillance system to better describe the burden of sports- and recreation-related TBI, including concussion, among youth. Given the limitations of TBI surveillance in general, CDC took this recommendation as a call to action to formulate and implement a robust pilot National Concussion Surveillance System that could estimate the public health burden of concussion and TBI among Americans from all causes of brain injury. Because of the constraints of identifying TBI in clinical settings, an alternative surveillance approach is to collect TBI data via a self-report survey. Before such a survey was piloted, it was necessary for CDC to develop a case definition for self-reported TBI. Objective This article outlines the rationale and process the CDC used to develop a tiered case definition for self-reported TBI to be used for surveillance purposes. Conclusion A tiered TBI case definition is proposed with tiers based on the type of sign/symptom(s) reported the number of symptoms reported, and the timing of symptom onset.

Objective Current methods used to measure incidence of traumatic brain injury (TBI) underestimate its true public health burden. The use of self-report surveys may be an approach to improve these estimates. An important step in public health surveillance is to define a public health problem using a case definition. The purpose of this article is to outline the process that the Centers for Disease Control and Prevention undertook to refine a TBI case definition to be used in surveillance using a self-report survey. Setting Survey. Participants A total of 10 030 adults participated via a random digit-dial telephone survey from September 2018 to September 2019. Main Measures Respondents were asked whether they had sustained a hit to the head in the preceding 12 months and whether they experienced a series of 12 signs and symptoms as a result of this injury. Design Head injuries with 1 or more signs/symptoms reported were initially categorized into a 3-tiered TBI case definition (probable TBI, possible TBI, and delayed possible TBI), corresponding to the level of certainty that a TBI occurred. Placement in a tier was compared with a range of severity measures (whether medical evaluation was sought, time to symptom resolution, self-rated social and work functioning); case definition tiers were then modified in a stepwise fashion to maximize differences in severity between tiers. Results There were statistically significant differences in the severity measure between cases in the probable and possible TBI tiers but not between other tiers. Timing of symptom onset did not meaningfully differentiate between cases on severity measures; therefore, the delayed possible tier was eliminated, resulting in 2 tiers: probable and possible TBI. Conclusion The 2-tiered TBI case definition that was derived from this analysis can be used in future surveillance efforts to differentiate cases by certainty and from noncases for the purpose of reporting TBI prevalence and incidence estimates. The refined case definition can help researchers increase the confidence they have in reporting survey respondents' self-reported TBIs as well as provide them with the flexibility to report an expansive (probable + possible TBI) or more conservative (probable TBI only) estimate of TBI prevalence.

Introduction Violence is a leading cause of morbidity and mortality among U.S. youth. More information on the health and economic burden of the most frequent assault mechanisms—or, causes (e.g., firearms, cut/pierce)—can support the development and implementation of effective public health strategies. Using nationally representative data sources, this study estimated the annual health and economic burden of U.S. youth violence by injury mechanism. Methods In 2023, CDC’s WISQARS provided the number of homicides and nonfatal assault ED visits by injury mechanism among U.S. youth aged 10–24 years in 2020, as well as the associated average economic costs of medical care, lost work, morbidity-related reduced quality of life, and value of statistical life. The Healthcare Cost and Utilization Project Nationwide Emergency Department Sample provided supplemental nonfatal assault incidence data for comprehensive reporting by injury mechanism. Results Of the $86B estimated annual economic burden of youth homicide,$78B was caused by firearms, $4B by cut/pierce injuries, and$1B by unspecified causes. Of the $36B billion estimated economic burden of nonfatal youth violence injuries,$19B was caused by struck by/against injuries, $3B by firearm injuries, and$365M by cut/pierce injuries. Conclusions The lethality of assault injuries affecting youth when a weapon is explicitly or likely involved is high—firearms and cut/pierce injuries combined account for nearly all youth homicides compared to one-tenth of nonfatal assault injury ED visits. There are numerous evidence-based policies, programs, and practices to reduce the number of lives lost or negatively impacted by youth violence.

OBJECTIVES Examine characteristics associated with firearm homicides of children aged 0–17 years precipitated by intimate partner violence (IPV). METHODS Data were from the Center for Disease Control and Prevention’s National Violent Death Reporting System (49 states, District of Columbia, Puerto Rico; 2003–2020). Logistic regression was used to examine associations between various characteristics and IPV among child firearm homicides. RESULTS From 2003–2020, a total of 11 594 child homicides were captured in the National Violent Death Reporting System, of which 49.3% (n = 5716) were firearm homicides; 12.0% (n = 686) of child firearm homicides were IPV-related. Among IPV-related child firearm homicides, 86.0% (n = 590) were child corollary victims (ie, children whose death was connected to IPV between others); 14.0% (n = 96) were teens killed by a current or former dating partner. Child firearm homicides had greater odds of involving IPV when precipitated by conflict, crises, and cooccurring with the perpetrator’s suicide compared with those without these characteristics. Over half of IPV-related firearm homicides of child corollary victims included homicide of the adult intimate partner, of which 94.1% were the child victim’s mother. Child firearm homicides perpetrated by mothers’ male companions (adjusted odds ratio, 6.9; 95% confidence interval, 3.9–12.1) and children’s fathers (adjusted odds ratio, 4.5; 95% confidence interval, 3.0–6.8) had greater odds of involving IPV compared with those perpetrated by mothers. CONCLUSIONS Multiple factors were associated with greater odds of child firearm homicides being IPV-related. Strategies promoting healthy intimate partner relationships starting at a young age; assessment of danger to children in IPV situations; strengthening economic supports for families; creating safe, stable, and nurturing relationships and environments for children; and addressing social and structural inequities are important for preventing firearm homicides of children, including those involving IPV.

Background The latest comprehensive diagnosis-specific estimates of hospital professional fees relative to facility fees are from 2004 to 2012. Objective Update professional fee ratio (PFR) estimates to improve cost analysis opportunities with hospital discharge data sources and compare them with previous PFR estimates. Subjects 2016–2020 MarketScan inpatient admissions and emergency department (ED) treat and release claims. Measures PFR was calculated as total admission or ED visit payment divided by facility-only payment. This measure can be multiplied by hospital facility costs to yield a total cost estimate. Research Design Generalized linear regression models controlling for selected patient and service characteristics were used to calculate adjusted mean PFR per admission or ED visit by health payer type (commercial or Medicaid) and by selected diagnostic categories representing all clinical diagnoses (Major Diagnostic Category, Diagnostic Related Group, and Clinical Classification Software Revised). Results Mean 2016–2020 PFR was 1.224 for admissions with commercial payers (n = 6.7 million admissions) and 1.178 for Medicaid (n = 4.2 million), indicating professional payments on average increased total payments by 22.4% and 17.8%, respectively, above facility-only payments. This is a 9% and 3% decline in PFR, respectively, compared with 2004 estimates. PFR for ED visits during 2016–2020 was 1.283 for commercial payers (n = 22.2 million visits) and 1.415 for Medicaid (n = 17.7 million). This is a 12% and 5% decline in PFR, respectively, compared with 2004 estimates. Conclusions Professional fees comprise a declining proportion of hospital-based care costs. Adjustments for professional fees are recommended when hospital facility-only financial data are used to estimate hospital care costs.

Purpose: Suicide is the second leading cause of death for adolescents in the United States; however, suicide is preventable and a better understanding of circumstances that contribute to death can inform prevention efforts. While the association between adolescent suicide and mental health is well established, multiple circumstances contribute to suicide risk. This study examines characteristics of adolescents who died by suicide and differences in circumstances between those with and without known mental health conditions at the time of death. Methods: Logistic regression models were used to estimate adjusted odds ratios and 95% confidence intervals of circumstances contributing to suicide between decedents with and without known mental health conditions using data from the 2013 to 2018 National Violent Death Reporting System (analyzed in 2021). Results: Decedents with a known mental health condition were 1.2-1.8 times more likely to experience problematic alcohol misuse, substance misuse, family and other nonintimate relationship problems, and school problems; however, there were no significant differences between those with and without a known mental health condition for the preceding circumstances of arguments or conflicts, criminal or legal problems, or any crisis occurring within the two weeks prior to death. Discussion: A comprehensive suicide prevention approach can address not only mental health conditions as a risk factor but also life stressors and other crises experienced among adolescents without known mental health conditions.

Importance: Direct costs of substance use disorders (SUDs) in the United States are incurred primarily among the working-age population. Quantifying the medical cost of SUDs in the employer-sponsored insurance (ESI) population can improve understanding of how SUDs are affecting workplaces and inform decision-making on the value of prevention strategies. Objective: To estimate the annual attributable medical cost of SUDs in the ESI population from the health care payer perspective. Design, setting, and participants: In this economic evaluation, Merative MarketScan 2018 databases were weighted to represent the non-Medicare eligible ESI population. Regression and mathematical modeling of medical expenditures controlled for insurance enrollee demographic, clinical, and insurance factors to compare enrollees with and without an SUD diagnosis to identify the annual attributable medical cost of SUDs. Data analysis was conducted from January to March 2022. Exposures: International Statistical Classification of Diseases, Tenth Revision, Clinical Modification SUD diagnoses on inpatient or outpatient medical records according to Clinical Classifications Software categories (alcohol-, cannabis-, hallucinogen-, inhalant-, opioid-, sedative-, stimulant-, and other substance-related disorders). Main outcomes and measures: Annual SUD medical cost in the ESI population overall and by substance type (eg, alcohol). Number of enrollees with an SUD diagnosis and the annual mean cost per affected enrollee of SUD diagnosis (any and by substance type) are also reported. Results: Among 162 million ESI enrollees, 2.3 million (1.4%) had an SUD diagnosis in 2018. The regression analysis sample included 210 225 individuals with an SUD diagnosis (121 357 [57.7%] male individuals; 68 325 [32.5%] aged 25-44 years) and 1 049 539 individuals with no SUD diagnosis. The mean annual medical cost attributable to SUD diagnosis per affected enrollee was $15 640 (95$15 340-$15 940), and the total annual medical cost in the ESI population was$35.3 billion (2018 USD). Alcohol use disorder ($10.2 billion) and opioid use disorder ($7.3 billion) were the most costly. Conclusions and relevance: In this economic evaluation of medical expenditures in the ESI population, the per-person and total medical costs of SUDs were substantial. Strategies to support employees and their health insurance dependents to prevent and treat SUDs can be considered in terms of potentially offsetting the existing high medical cost of SUDs. Medical expenditures for SUDs represent the minimum direct cost that employers and health insurers face because not all people with SUDs have a diagnosis, and costs related to absenteeism, presenteeism, job retention, and mortality are not addressed.