Predictors of applicant pool racial and ethnic diversity among physician assistant education programs: a national cross-sectional cohort study.

BACKGROUND: Numerous studies have demonstrated that the increasing racial and ethnic diversity of the US population benefits from access to healthcare providers from similarly diverse backgrounds. Physician assistant (PA) education programs have striven to increase the diversity of the profession, which is predominantly non-Hispanic white, by focusing on admitting students from historically excluded populations. However, strategies such as holistic admissions are predicated on the existence of racially and ethnically diverse applicant pools. While studies have examined correlates of matriculation into a medical education program, this study looks earlier in the pipeline and investigates whether applicant - not matriculant - pool diversity varies among PA programs with different characteristics. METHODS: Data were drawn from the 2017-2018 Central Application Service for PAs admissions cycle. Applications to programs with pre-professional tracks and applicants missing race/ethnicity data were excluded, resulting in data from 26,600 individuals who applied to 189 PA programs. We summarized the racial and ethnic diversity of each program's applicant pools using: [1]the proportion of underrepresented minority (URM) students, [2]the proportion of students with backgrounds underrepresented in medicine (URiM), and [3]Simpson's diversity index of a 7-category race/ethnicity combination. We used multiple regressions to model each diversity metric as a function of program characteristics including class size, accreditation status, type of institution, and other important features. RESULTS: Regardless of the demographic diversity metric examined, we found that applicant diversity was higher among provisionally accredited programs and those receiving more applications. We also identified trends suggesting that programs in more metropolitan areas were able to attract more diverse applicants. Programs that did not require the GRE were also able to attract more diverse applicants when considering the URM and SDI metrics, though results for URiM were not statistically significant. CONCLUSIONS: Our findings provide insights into modifiable (e.g., GRE requirement) and non-modifiable (e.g., provisionally accredited) program characteristics that are associated with more demographically diverse applicant pools.

Long-term PM2.5 exposure and sepsis mortality in a US medicare cohort.

BACKGROUND: Risk factors contributing to sepsis-related mortality include clinical conditions such as cardiovascular disease, chronic lung disease, and diabetes, all of which have also been shown to be associated with air pollution exposure. However, the impact of chronic exposure to air pollution on sepsis-related mortality has been little studied.  METHODS: In a cohort of 53 million Medicare beneficiaries (228,439 sepsis-related deaths) living across the conterminous United States between 2000 and 2008, we examined the association of long-term PM2.5 exposure and sepsis-related mortality. For each Medicare beneficiary (ages 65-120), we estimated the 12-month moving average PM2.5 concentration for the 12 month before death, for their ZIP code of residence using well validated GIS-based spatio-temporal models. Deaths were categorized as sepsis-related if they have ICD-10 codes for bacterial or other sepsis. We used Cox proportional hazard models to assess the association of long-term PM2.5 exposure on sepsis-related mortality. Models included strata for age, sex, race, and ZIP code and controlled for neighborhood socio-economic status (SES). We also evaluated confounding through adjustment of neighborhood behavioral covariates. RESULTS: A 10 µg/m3 increase in 12-month moving average PM2.5 was associated with a 9.1% increased risk of sepsis mortality (95% CI: 3.6-14.9) in models adjusted for age, sex, race, ZIP code, and SES. HRs for PM2.5 were higher and statistically significant for older (> 75), Black, and urban beneficiaries. In stratified analyses, null associations were found for younger beneficiaries (65-75), beneficiaries who lived in non-urban ZIP codes, and those residing in low-SES urban ZIP codes. CONCLUSIONS: Long-term PM2.5 exposure is associated with elevated risks of sepsis-related mortality.

Differential impacts of particulate air pollution exposure on early and late stages of spermatogenesis.

BACKGROUND: Despite increasing evidence that particulate air pollution has adverse effects on human semen quality, few studies examine the impact of air pollution on clinically relevant thresholds used to diagnose male fertility problems. Furthermore, exposure is often assessed using average air pollution levels in a geographic area rather than individualized estimates. Finally, physiologically-informed exposure windows are inconsistent. OBJECTIVES: We sought to test the hypothesis that airborne particulate exposures during early-phase spermatogenesis will have a differential impact on spermatogenic formation compared to late-phase exposures, using an individualized model of exposure to particulate matter ≤ 2.5 µm and ≤ 10 µm (PM2.5 and PM10, respectively). METHODS: From an original cohort of 183 couples, we conducted a retrospective analysis of 130 healthy males seeking to become parents, using spermatogenesis-relevant exposure windows of 77-34 days and 37-0 days prior to semen collection to encompass sperm development stages of mitosis/meiosis and spermiogenesis, respectively. Individualized residential exposure to PM2.5 and PM10 was estimated by selecting multiple air pollution sensors within the same geographic air basin as participants and employing inverse distance weighting to calculate mean daily exposure levels. We used multiple logistic regression to assess the association between pollution, temperature, and dichotomized World Health Organization semen parameters. RESULTS: During the early phase of spermatogenesis, air pollution exposure is associated with 1.52 (95% CI: 1.04-2.32) times greater odds of < 30% normal heads per 1-unit increase in IQR for PM2.5. In the late phase of spermatogenesis, air pollution exposure is associated with 0.35 (95% CI: 0.10-0.74) times greater odds of semen concentration < 15 million/mL per 1-unit increase in IQR for PM2.5, and 0.28 (95% CI: 0.07-0.72) for PM10. CONCLUSION: Particulate exposure has a differential and more deleterious impact on sperm during early-phase spermatogenesis than late-phase.

The Impact of Long-Term Air Pollution Exposure on Type 1 Diabetes Mellitus-Related Mortality among U.S. Medicare Beneficiaries.

BACKGROUND: Little of the previous literature has investigated associations between air pollution exposure and type 1 diabetes mellitus (T1DM)-related mortality, despite a well-established link between air pollution exposure and other autoimmune diseases. METHODS: In a cohort of 53 million Medicare beneficiaries living across the conterminous United States, we used Cox proportional hazard models to assess the association of long-term PM2.5 and NO2 exposures on T1DM-related mortality from 2000 to 2008. Models included strata for age, sex, race, and ZIP code and controlled for neighborhood socioeconomic status (SES); we additionally investigated associations in two-pollutant models, and whether associations were modified by participant demographics. RESULTS: A 10 µg/m3 increase in 12-month average PM2.5 (HR: 1.183; 95% CI: 1.037-1.349) and a 10 ppb increase in NO2 (HR: 1.248; 95% CI: 1.089-1.431) was associated with an increased risk of T1DM-related mortality in age-, sex-, race-, ZIP code-, and SES-adjusted models. Associations for both pollutants were consistently stronger among Black (PM2.5: HR:1.877, 95% CI: 1.386-2.542; NO2: HR: 1.586, 95% CI: 1.258-2.001) and female (PM2.5: HR:1.297, 95% CI: 1.101-1.529; NO2: HR: 1.390, 95% CI: 1.187-1.627) beneficiaries. CONCLUSIONS: Long-term NO2 and, to a lesser extent, PM2.5 exposure is associated with statistically significant elevations in T1DM-related mortality risk.

Impacts of Indoor Dust Exposure on Human Colonic Cell Viability, Cytotoxicity and Apoptosis.

INTRODUCTION: Environmental exposure to indoor dust is known to be associated with myriad health conditions, especially among children. Established routes of exposure include inhalation and non-dietary ingestion, which result in the direct exposure of gastrointestinal epithelia to indoor dust. Despite this, little prior research is available on the impacts of indoor dust on the health of human gastrointestinal tissue. METHODS: Cultured human colonic (CCD841) cells were exposed for 24 h to standard trace metal dust (TMD) and organic contaminant dust (OD) samples at the following concentrations: 0, 10, 25, 50, 75, 100, 250, and 500 µg/mL. Cell viability was assessed using an MTT assay and protease analysis (glycyl-phenylalanyl-aminofluorocoumarin (GF-AFC)); cytotoxicity was assessed with a lactate dehydrogenase release assay, and apoptosis was assessed using a Caspase-Glo 3/7 activation assay. RESULTS: TMD and OD decreased cellular metabolic and protease activity and increased apoptosis and biomarkers of cell membrane damage (LDH) in CCD841 human colonic epithelial cells. Patterns appeared to be, in general, dose-dependent, with the highest TMD and OD exposures associated with the largest increases in apoptosis and LDH, as well as with the largest decrements in metabolic and protease activities. CONCLUSIONS: TMD and OD exposure were associated with markers of reduced viability and increased cytotoxicity and apoptosis in human colonic cells. These findings add important information to the understanding of the physiologic effects of indoor dust exposure on human health. The doses used in our study represent a range of potential exposure levels, and the effects observed at the higher doses may not necessarily occur under typical exposure conditions. The effects of long-term, low-dose exposure to indoor dust are still not fully understood and warrant further investigation. Future research should explore these physiological mechanisms to further our understanding and inform public health interventions.

Associations between state scope of practice laws and US physician assistant wages from 1997 to 2017: a longitudinal analysis.

OBJECTIVE: The purpose of this study is to determine whether, and to what degree, variations in physician assistant (PA) state scope of practice (SOP) laws across states are associated with (1) PA median wage over time and (2) if a specific SOP key element has greater impact on PA median wage than others. We hypothesise that expanded SOP laws will be associated with higher PA wage. DESIGN: Longitudinal analysis from 1997 to 2017. SETTING: Fifty states and the District of Columbia (US capital region). PARTICIPANTS: Employed PAs from 1997 to 2017. METHODS: Four national data sets were combined to allow for longitudinal analysis of state-level annual PA wage and state SOP laws. We used linear regression models to explore the associations of SOP elements with PA wage in 5-year intervals and individual growth models to assess the change in PA annual wage over the study period. RESULTS: There was a 220% increase in weighted PA annual wage over two decades. There was a positive linear correlation between annual wage and age in 2012 and 2017 (r=0.52, p<0.01; r=0.29, p=0.04, respectively). The adjusted R2 for individual SOP elements in the selected years were all small (range: 0.0-0.29), with no appreciable pattern across time for any SOP element. In 1997, several SOP laws show association with median wage but this impact disappears over time. CONCLUSIONS: PA median wage has risen over twofold in the past two decades, with the rise in PA wage mainly explained by time and provider age. In 1997 some SOP elements were associated with increased average wage; however, the impact of this increase diminished over time in all such instances. As the PA profession moves towards Optimal Team Practice, future research should examine if this move towards greater autonomy impacts wage.

Increasing Racial and Ethnic Diversity at the University of Utah Physician Assistant Program.

BACKGROUND AND OBJECTIVES: Among the oldest in the nation, the University of Utah Physician Assistant Program (UPAP) serves the state of Utah and surrounding areas and is a division of the Department of Family and Preventive Medicine. Recognizing the need to produce health care providers from diverse racial and ethnic backgrounds, UPAP instituted structural changes to improve student compositional diversity. This paper is a presentation and evaluation of the changes made to determine their relationship with compositional diversity, ultimate practice setting, and national rankings. METHODS: UPAP changed diversity messaging, curriculum, efforts in admissions, recruitment, and retention to improve the representation of Black, Latinx, American Indian/Alaska Native, and Native Hawaiian/Other Pacific Islander students, as well as those from educationally and economically disadvantaged backgrounds. RESULTS: UPAP tripled the number of underrepresented minority matriculated students over the course of five admitted classes, while simultaneously increasing the proportion of students from educationally or economically disadvantaged backgrounds. UPAP maintains both high boards pass rate and top national rankings, (number two ranking in public physician assistant program and number four overall program in the United States). CONCLUSIONS: The UPAP experience demonstrates that intentional diversity efforts are associated with improvement in racial/ethnic diversity and national rankings. Other medical school graduate programs, specifically the medical doctor (MD), public health, and basic science programs can use this model to improve their compositional diversity.

Collaborative practice trends in US physician office visits: an analysis of the National Ambulatory Medical Care Survey (NAMCS), 2007-2016.

OBJECTIVE: Practice arrangements in physician offices were characterised by examining the share of visits that involved physician assistants (PAs) and nurse practitioners (NPs). The hypothesis was that collaborative practice (ie, care delivered by a dyad of physician-PA and/or physician-NP) was increasing. DESIGN: Temporal ecological study. SETTING: Non-federal physician offices. PARTICIPANTS: Patient visits to a physician, PA or NP, spanning years 2007-2016. METHODS: A stratified random sample of visits to office-based physicians was pooled through the National Ambulatory Medical Care Survey public use linkage file. Among 317 674 visits to physicians, PAs or NPs, solo and collaborative practices were described and compared over two timespans of 2007-2011 and 2012-2016. Weighted patient visits were aggregated in bivariate analyses to achieve nationally representative estimates. Survey statistics assessed patient demographic characteristics, reason for visit and visit specialty by provider type. RESULTS: Within years 2007-2011 and 2012-2016, there were 4.4 billion and 4.1 billion physician office visits (POVs), respectively. Comparing the two timespans, the rate of POVs with a solo PA (0.43% vs 0.21%) or NP (0.31% vs 0.17%) decreased. Rate of POVs with a collaborative physician-PA increased non-significantly. Rate of POVs with a collaborative physician-NP (0.49% vs 0.97%, p<0.01) increased. Overall, collaborative practice, in particular physician-NP, has increased in recent years (p<0.01), while visits handled by a solo PA or NP decreased (p<0.01). In models adjusted for patient age and chronic conditions, the odds of collaborative practice in years 2012-2016 compared with years 2007-2011 was 35% higher (95% CI 1.01 to 1.79). Furthermore, in 2012-2016, NPs provided more independent primary care, and PAs provided more independent care in a non-primary care medical specialty. Preventive visits declined among all providers. CONCLUSIONS: In non-federal physician offices, collaborative care with a physician-PA or physician-NP appears to be a growing part of office-based healthcare delivery.

Predicting Physician Assistant Program Matriculation Among Diverse Applicants: The Influences of Underrepresented Minority Status, Age, and Gender.

PURPOSE: Health professions schools can foster a diverse medical workforce by ensuring equal educational access for students of varied backgrounds. This study examined how physician assistant (PA) applicants' demographic characteristics and prior academic history affected likelihood of PA program matriculation. METHOD: The authors used national application data from the 2015-2016 PA application cycle to investigate associations between applicants' underrepresented minority (URM) status, age, and gender, and likelihood of matriculating into a PA program. Effects were examined alone and after adjusting for other demographics and potential confounders (number of applications submitted, patient care hours, academic achievement). The authors tested whether odds of matriculation differed among demographic subgroups with and without current Graduate Record Examinations (GRE) scores. RESULTS: In univariate models, likelihood of matriculation was lower among URM, older, and male applicants. In fully adjusted models, the URM effect became nonsignificant and the gender effect reversed, while older applicants remained less likely to matriculate. URM and age, but not gender, effects differed by GRE status; only URMs and older applicants without current GRE scores were less likely to matriculate than non-URMs and younger applicants. CONCLUSIONS: Findings that URMs, older individuals, and men had lower matriculation odds changed when controlling for academic achievement and GRE status, indicating the importance of these components in the admissions process. URM and age findings were contingent on GRE status such that odds of matriculation decreased among URM and older applicants without GRE scores, suggesting that standardized test requirements may be a barrier to PA workforce diversity.