130 research outputs found

    Propensity Score Estimation to Address Calendar Time-Specific Channeling in Comparative Effectiveness Research of Second Generation Antipsychotics

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    BackgroundChanneling occurs when a medication and its potential comparators are selectively prescribed based on differences in underlying patient characteristics. Drug safety advisories can provide new information regarding the relative safety or effectiveness of a drug product which might increase selective prescribing. In particular, when reported adverse effects vary among drugs within a therapeutic class, clinicians may channel patients toward or away from a drug based on the patient's underlying risk for an adverse outcome. If channeling is not identified and appropriately managed it might lead to confounding in observational comparative effectiveness studies.ObjectiveTo demonstrate channeling among new users of second generation antipsychotics following a Food and Drug Administration safety advisory and to evaluate the impact of channeling on cardiovascular risk estimates over time.Data SourceFlorida Medicaid data from 2001–2006.Study DesignRetrospective cohort of adults initiating second generation antipsychotics. We used propensity scores to match olanzapine initiators with other second generation antipsychotic initiators. To evaluate channeling away from olanzapine following an FDA safety advisory, we estimated calendar time-specific propensity scores. We compare the performance of these calendar time-specific propensity scores with conventionally-estimated propensity scores on estimates of cardiovascular risk.Principal FindingsIncreased channeling away from olanzapine was evident for some, but not all, cardiovascular risk factors and corresponded with the timing of the FDA advisory. Covariate balance was optimized within period and across all periods when using the calendar time-specific propensity score. Hazard ratio estimates for cardiovascular outcomes did not differ across models (Conventional PS: 0.97, 95%CI: 0.81–3.18 versus calendar time-specific PS: 0.93, 95%CI: 0.77–3.04).ConclusionsChanges in channeling over time was evident for several covariates but had limited impact on cardiovascular risk estimates, possibly due to unmeasured confounding. Although calendar time-specific propensity scores appear to improve covariate balance, the impact on comparative effectiveness results is limited in this setting

    Epidemiology of Traumatic Posterior Hip Instability in the National Football League

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    BACKGROUND There is a paucity of literature regarding injury incidence, mechanism, and return to play in National Football League (NFL) players who have sustained traumatic posterior hip instability. PURPOSE To describe the incidence of traumatic posterior hip instability and the rate of return to play in NFL players across 18 seasons. STUDY DESIGN Descriptive epidemiology study. METHODS We retrospectively assessed all traumatic posterior hip dislocations/subluxations that occurred during football-related activities in the NFL seasons from 2000 through 2017. Player demographics and injury data (injury mechanism, season of injury, treatment, days missed, and return to play time) were collected from all 32 NFL teams prospectively through a leaguewide electronic health record system. Descriptive statistics are presented. RESULTS Across the 18 NFL seasons, 16 posterior hip instability injuries in 14 players were reported, with a maximum incidence of 4 (25%) in 2013. Posterior hip instability was predominantly sustained by offensive players (64.3%), with tight ends being the most affected (31.3%). Half of the injuries occurred during the regular season, 43.8% in the preseason, and 6.2% in the offseason. Of all injuries, 37.5% were noncontact, while 56.3% involved contact (direct or indirect), and 6.2% were of unknown mechanism. Among noncontact injuries, 66.7% occurred during cutting and change of direction while sprinting. The time of return to full participation was documented for 11 of the 16 reported injuries (68.8%); among them, the mean time loss was 136.7 ± 83.8 days-143.3 ± 99.6 days if the player underwent surgery (n = 4) and 116.7 ± 76.2 days missed by players without surgery (n = 6)-the treatment modality was unknown in 1 player. CONCLUSION Although the incidence of traumatic posterior hip instability during the study period was low, all injured athletes missed time from football activities and competitions. Injuries that required surgery led to more missed time than those that did not. Ongoing research to understand risk factors and mechanisms of this injury, in conjunction with improvements to prevention and rehabilitation protocols, is necessary to ensure the safety of professional American football players

    MRI findings associated with anterior cruciate ligament tears in National Football League athletes

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    BACKGROUND: Anterior cruciate ligament (ACL) tears are a high-frequency injury requiring a lengthy recovery in professional American football players. Concomitant pathology associated with ACL tears as identified on magnetic resonance imaging (MRI) is not well understood in these athletes. PURPOSE: To describe the MRI findings of concomitant injuries associated with ACL tears among athletes in the National Football League (NFL). STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Of 314 ACL injuries in NFL athletes from 2015 through 2019, 191 complete MRI scans from the time of primary ACL injury were identified and reviewed by 2 fellowship-trained musculoskeletal radiologists. Data were collected on ACL tear type and location, as well as presence and location of bone bruises, meniscal tears, articular cartilage pathology, and concomitant ligament pathology. Mechanism data from video review were linked with imaging data to assess association between injury mechanism (contact vs noncontact) and presence of concomitant pathology. RESULTS: Bone bruises were evident in 94.8% of ACL tears in this cohort, most often in the lateral tibial plateau (81%). Meniscal, additional ligamentous, and/or cartilage injury was present in 89% of these knees. Meniscal tears were present in 70% of knees, lateral (59%) more than medial (41%). Additional ligamentous injury was present in 71% of all MRI scans, more often a grade 1/2 sprain (67%) rather than a grade 3 tear (33%), and most often involving the medial collateral ligament (MCL) (57%) and least often the posterior cruciate ligament (10%). Chondral damage was evident in 49% of all MRI scans, with ≥1 full-thickness defect in 25% of all MRI scans, most often lateral. Most (79%) ACL tears did not involve direct contact to the injured lower extremity. Direct contact injuries (21%) were more likely to have a concomitant MCL tear and/or medial patellofemoral ligament injury and less likely to have a medial meniscal tear. CONCLUSION: ACL tears were rarely isolated injuries in this cohort of professional American football athletes. Bone bruises were almost always present, and additional meniscal, ligamentous, and chondral injuries were also common. MRI findings varied by injury mechanism

    Racial disparities in receipt and comparative effectiveness of oxaliplatin for stage III colon cancer in older adults

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    African Americans (AA) in the United States have higher rates of colon cancer (CC) mortality than other races. This study examines the use of oxaliplatin, a novel chemotherapeutic agent approved in 2004, among AA and Caucasian Americans (CA) patients with stage III colon cancer to understand whether differential receipt or differential effectiveness of the drug may explain the racial disparity in CC mortality

    Trends in Antibiotic Use by Birth Season and Birth Year

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    OBJECTIVES: We examined 2 birth cohort effects on antibiotic prescribing during the first year of life (henceforth, infancy) in Denmark: (1) the birth season effect on timing and overall occurrence of antibiotic prescribing, and (2) the birth year effect amid emerging nationwide pneumococcal vaccination programs and changing prescribing guidelines. METHODS: We linked data for all live births in Denmark from 2004 to 2012 (N = 561 729) across the National Health Service Prescription Database, Medical Birth Registry, and Civil Registration System. Across birth season and birth year cohorts, we estimated 1-year risk, rate, and burden of redeemed antibiotic prescriptions during infancy. We used interrupted time series methods to assess prescribing trends across birth year cohorts. Graphical displays of all birth cohort effect data are included. RESULTS: The 1-year risk of having at least 1 redeemed antibiotic prescription during infancy was 39.5% (99% confidence interval [CI]: 39.3% to 39.6%). The hazard of a first prescription increased with age throughout infancy and varied by season; subsequently, Kaplan-Meier-derived risk functions varied by birth season cohort. After rollout of a first vaccination program and new antibiotic prescribing guidelines, 1-year risk decreased by 4.4% over 14 months (99% CI: 3.4% to 5.5%); it decreased again after rollout of a second vaccination program by 6.9% over 3 years (99% CI: 4.4% to 9.3%). CONCLUSIONS: In Denmark, birth season and birth year cohort effects influenced timing and risk of antibiotic prescribing during infancy. Future studies of antibiotic stewardship, effectiveness, and safety in children should consider these cohort effects, which may render some children inherently more susceptible than others to downstream antibiotic effects

    Viral Kinetics of Sequential SARS-CoV-2 Infections

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    The impact of a prior SARS-CoV-2 infection on the progression of subsequent infections has been unclear. Using a convenience sample of 94,812 longitudinal RT-qPCR measurements from anterior nares and oropharyngeal swabs, we identified 71 individuals with two well-sampled SARS-CoV-2 infections between March 11th, 2020, and July 28th, 2022. We compared the SARS-CoV-2 viral kinetics of first vs. second infections in this group, adjusting for viral variant, vaccination status, and age. Relative to first infections, second infections usually featured a faster clearance time. Furthermore, a person\u27s relative (rank-order) viral clearance time, compared to others infected with the same variant, was roughly conserved across first and second infections, so that individuals who had a relatively fast clearance time in their first infection also tended to have a relatively fast clearance time in their second infection (Spearman correlation coefficient: 0.30, 95% credible interval (0.12, 0.46)). These findings provide evidence that, like vaccination, immunity from a prior SARS-CoV-2 infection shortens the duration of subsequent acute SARS-CoV-2 infections principally by reducing viral clearance time. Additionally, there appears to be an inherent element of the immune response, or some other host factor, that shapes a person\u27s relative ability to clear SARS-CoV-2 infection that persists across sequential infections

    Using coupons to encourage healthier child snack purchases in corner stores: results from the CHOMPS study

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    ObjectivesTo examine youths’ (ages 6–15 years) autonomous snack purchases in corner stores and pilot use of coupons to encourage more healthful snack purchases.MethodsThis pilot study involved four corner stores proximal to K-8 schools in Massachusetts. Kids-only coupons of varying discounts were provided in store and paired with simple visual and verbal economic and health messages. Observational data about youths’ autonomous snack purchases was recorded pre- and post-intervention. Outcomes of interest were snack item, price, and nutrient content. Comparisons of purchase characteristics and nutritional content across intervention conditions were made using Chi-squared and t-tests.ResultsAcross all stores, 2,973 purchase observations were recorded totaling approximately $6,000. Researchers estimated that about 55% of shoppers were 10–12 years old. Modest coupon usage (2.2% of purchases) was noted. However, candy purchases decreased, and the percentage of purchase events that included at least one healthier food item more than doubled, regardless of coupon use. Improvements in the nutritional content of snacks were also observed.ConclusionKids-only coupons have the potential to assist with shifting autonomous snack purchase behavior in outside of school settings

    Severe Acute Respiratory Syndrome Coronavirus 2 Reinfection: A Case Series From a 12-Month Longitudinal Occupational Cohort

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    Findings are described in 7 patients with severe acute respiratory syndrome coronavirus 2 reinfection from the National Basketball Association 2020-2021 occupational testing cohort, including clinical details, antibody test results, genomic sequencing, and longitudinal reverse-transcription polymerase chain reaction results. Reinfections were infrequent and varied in clinical presentation, viral dynamics, and immune response

    Viral dynamics of acute SARS-CoV-2 infection and applications to diagnostic and public health strategies.

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    SARS-CoV-2 infections are characterized by viral proliferation and clearance phases and can be followed by low-level persistent viral RNA shedding. The dynamics of viral RNA concentration, particularly in the early stages of infection, can inform clinical measures and interventions such as test-based screening. We used prospective longitudinal quantitative reverse transcription PCR testing to measure the viral RNA trajectories for 68 individuals during the resumption of the 2019-2020 National Basketball Association season. For 46 individuals with acute infections, we inferred the peak viral concentration and the duration of the viral proliferation and clearance phases. According to our mathematical model, we found that viral RNA concentrations peaked an average of 3.3 days (95% credible interval [CI] 2.5, 4.2) after first possible detectability at a cycle threshold value of 22.3 (95% CI 20.5, 23.9). The viral clearance phase lasted longer for symptomatic individuals (10.9 days [95% CI 7.9, 14.4]) than for asymptomatic individuals (7.8 days [95% CI 6.1, 9.7]). A second test within 2 days after an initial positive PCR test substantially improves certainty about a patient's infection stage. The effective sensitivity of a test intended to identify infectious individuals declines substantially with test turnaround time. These findings indicate that SARS-CoV-2 viral concentrations peak rapidly regardless of symptoms. Sequential tests can help reveal a patient's progress through infection stages. Frequent, rapid-turnaround testing is needed to effectively screen individuals before they become infectious
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