Overcoming Obstacles: Barriers to Virtual Care Use Among Video-Enabled Tablet Recipients in the Veterans Health Administration

INTRODUCTION

The Veterans Health Administration (VHA) distributes video-enabled tablets to individuals with barriers to accessing care. Data suggests that many tablets are under-used. We surveyed Veterans who received a tablet to identify barriers that are associated with lower use, and evaluated the impact of a telephone-based orientation call on reported barriers and future video use.

METHODS

We used a national survey to assess for the presence of 13 barriers to accessing video-based care, and then calculated the prevalence of the barriers stratified by video care utilization in the 6 months after survey administration. We used multivariable modeling to examine the association between each barrier and video-based care use and evaluated whether a telephone-based orientation modified this association.

RESULTS

The most prevalent patient-reported barriers to video-based care were not knowing how to schedule a visit, prior video care being rescheduled/canceled, and past problems using video care. Following adjustment, individuals who reported vision or hearing difficulties and those who reported that video care does not provide high-quality care had a 19% and 12% lower probability of future video care use, respectively. Individuals who reported no interest in video care, or did not know how to schedule a video care visit, had an 11% and 10% lower probability of being a video care user, respectively. A telephone-based orientation following device receipt did not improve the probability of being a video care user.

DISCUSSION

Barriers to engaging in virtual care persist despite access to video-enabled devices. Targeted interventions beyond telephone-based orientation are needed to facilitate adoption and engagement in video visits.

Diesel exhaust and respiratory dust exposure in miners and chronic obstructive pulmonary disease (COPD) mortality in DEMS II

BACKGROUND

Diesel exhaust and respirable dust exposures in the mining industry have not been studied in depth with respect to non-malignant respiratory disease including chronic obstructive pulmonary disease (COPD), with most available evidence coming from other settings.

OBJECTIVES

To assess the relationship between occupational diesel exhaust and respirable dust exposures and COPD mortality, while addressing issues of survivor bias in exposed miners.

METHODS

The study population consisted of 11,817 male workers from the Diesel Exhaust in Miners Study II, followed from 1947 to 2015, with 279 observed COPD deaths. We fit Cox proportional hazards models for the relationship between respirable elemental carbon (REC) and respirable dust (RD) exposure and COPD mortality. To address healthy worker survivor bias, we leveraged the parametric g-formula to assess effects of hypothetical interventions on both exposures.

RESULTS

Cox models yielded elevated estimates for the associations between average intensity of REC and RD and COPD mortality, with hazard ratios (HR) corresponding to an interquartile range width increase in exposure of 1.46 (95 % confidence interval (CI): 1.12, 1.91) and 1.20 (95 % CI: 0.96, 1.49), respectively for each exposure. HRs for cumulative exposures were negative for both REC and RD. Based on results from the parametric g-formula, the risk ratio (RR) for COPD mortality comparing risk under an intervention eliminating REC to the observed risk was 0.85 (95 % CI: 0.55, 1.06), equivalent to an attributable risk of 15 %. The corresponding RR comparing risk under an intervention eliminating RD to the observed risk was 0.93 (95 % CI: 0.56, 1.31).

CONCLUSIONS

Our findings, based on data from a cohort of nonmetal miners, are suggestive of an increased risk of COPD mortality associated with REC and RD, as well as evidence of survivor bias in this population leading to negative associations between cumulative exposures and COPD mortality in traditional regression analysis.

Adoption and Sustained Use of Primary Care Video Visits Among Veterans with VA Video-Enabled Tablets

In 2020, the U.S. Department of Veterans Affairs (VA) expanded an initiative to distribute video-enabled tablets to Veterans with limited virtual care access. We examined patient characteristics associated with adoption and sustained use of video-based primary care among Veterans. We conducted a retrospective cohort study of Veterans who received VA-issued tablets between 3/11/2020-9/10/2020. We used generalized linear models to evaluate the sociodemographic and clinical factors associated with video-based primary care adoption (i.e., likelihood of having a primary care video visit) and sustained use (i.e., rate of video care) in the six months after a Veteran received a VA-issued tablet. Of the 36,077 Veterans who received a tablet, 69% had at least one video-based visit within six months, and 24% had a video-based visit in primary care. Veterans with a history of housing instability or a mental health condition, and those meeting VA enrollment criteria for low-income were significantly less likely to adopt video-based primary care. However, among Veterans who had a video visit in primary care (e.g., those with at least one video visit), older Veterans, and Veterans with a mental health condition had more sustained use (higher rate) than younger Veterans or those without a mental health condition. We found no differences in adoption of video-based primary care by rurality, age, race, ethnicity, or low/moderate disability and high disability priority groups compared to Veterans with no special enrollment category. VA's tablet initiative has supported many Veterans with complex needs in accessing primary care by video. While Veterans with certain social and clinical challenges were less likely to have a video visit, those who adopted video telehealth generally had similar or higher rates of sustained use. These patterns suggest opportunities for tailored interventions that focus on needs specific to initial uptake vs. sustained use of video care.

Variation in initial and continued use of primary, mental health, and specialty video care among Veterans

OBJECTIVE

To identify which Veteran populations are routinely accessing video-based care.

DATA SOURCES AND STUDY SETTING

National, secondary administrative data from electronic health records at the Veterans Health Administration (VHA), 2019-2021.

STUDY DESIGN

This retrospective cohort analysis identified patient characteristics associated with the odds of using any video care; and then, among those with a previous video visit, the annual rate of video care utilization. Video care use was reported overall and stratified into care type (e.g., primary, mental health, and specialty video care) between March 10, 2020 and February 28, 2021.

DATA COLLECTION

Veterans active in VA health care (>1 outpatient visit between March 11, 2019 and March 10, 2020) were included in this study.

PRINCIPAL FINDINGS

Among 5,389,129 Veterans in this evaluation, approximately 27.4% of Veterans had at least one video visit. We found differences in video care utilization by type of video care: 14.7% of Veterans had at least one primary care video visit, 10.6% a mental health video visit, and 5.9% a specialty care video visit. Veterans with a history of housing instability had a higher overall rate of video care driven by their higher usage of video for mental health care compared with Veterans in stable housing. American Indian/Alaska Native Veterans had reduced odds of video visits, yet similar rates of video care when compared to White Veterans. Low-income Veterans had lower odds of using primary video care yet slightly elevated rates of primary video care among those with at least one video visit when compared to Veterans enrolled at VA without special considerations.

CONCLUSIONS

Variation in video care utilization patterns by type of care identified Veteran populations that might require greater resources and support to initiate and sustain video care use. Our data support service specific outreach to homeless and American Indian/Alaska Native Veterans.

Risk factors for meticillin-resistant Staphylococcus aureus (MRSA) carriage in MRSA-exposed household pets

BACKGROUND

Household pets can carry meticillin-resistant Staphylococcus aureus (MRSA) introduced to the home by their human companions. Specific factors promoting pet carriage of this pathogen have not been fully elucidated.

OBJECTIVE

This study evaluated MRSA cultured from pets and the home environment in households where a human infected with MRSA had been identified, and aimed to determine potential risk factors for pet MRSA carriage.

MATERIALS AND METHODS

Humans diagnosed with community-associated MRSA (CA-MRSA) skin or soft-tissue infection (SSTI) in the mid-Atlantic United States were identified. One hundred forty-two dogs and cats from 57 affected households were identified of which 134 (94.4%) pets and the household environment were sampled for bacterial culture, PCR confirmation and spa-typing for MRSA strain determination. Samples were obtained 3 months later from 86 pets.

RESULTS

At baseline, 12 (9.0%) pets carried MRSA. Potential risk factors associated with carriage included pet bed (environmental) MRSA contamination, flea infestation and prior antimicrobial use in the pet. Pets tended to carry human-adapted MRSA strains and spa-types of MRSA isolates cultured from pets were concordant with strains cultured from the home environment in seven of eight homes (87.5%) at baseline.

CONCLUSIONS AND CLINICAL RELEVANCE

Results may inform risk-based veterinary clinical recommendations and provide evidence for selective pet testing as a possible alternative to early removal of pets from the homes of humans infected with MRSA. MRSA contamination of the home environment is likely an important risk factor for pet MRSA carriage, and household interventions should be considered to reduce risk of MRSA carriage in exposed pets.

Overcoming Access Barriers for Veterans: Cohort Study of the Distribution and Use of Veterans Affairs' Video-Enabled Tablets Before and During the COVID-19 Pandemic

BACKGROUND

During the COVID-19 pandemic, as health care services shifted to video- and phone-based modalities for patient and provider safety, the Veterans Affairs (VA) Office of Connected Care widely expanded its video-enabled tablet program to bridge digital divides for veterans with limited video care access.

OBJECTIVE

This study aimed to characterize veterans who received and used US Department of VA-issued video-enabled tablets before versus during the COVID-19 pandemic.

METHODS

We compared sociodemographic and clinical characteristics of veterans who received VA-issued tablets during 6-month prepandemic and pandemic periods (ie, from March 11, 2019, to September 10, 2019, and from March 11, 2020, to September 10, 2020). Then, we examined characteristics associated with video visit use for primary and mental health care within 6 months after tablet shipment, stratifying models by timing of tablet receipt.

RESULTS

There was a nearly 6-fold increase in the number of veterans who received tablets in the pandemic versus prepandemic study periods (n=36,107 vs n=6784, respectively). Compared to the prepandemic period, tablet recipients during the pandemic were more likely to be older (mean age 64 vs 59 years), urban-dwelling (24,504/36,107, 67.9% vs 3766/6784, 55.5%), and have a history of housing instability (8633/36,107, 23.9% vs 1022/6784, 15.1%). Pandemic recipients were more likely to use video care (21,090/36,107, 58.4% vs 2995/6784, 44.2%) and did so more frequently (5.6 vs 2.3 average encounters) within 6 months of tablet receipt. In adjusted models, pandemic and prepandemic video care users were significantly more likely to be younger, stably housed, and have a mental health condition than nonusers.

CONCLUSIONS

Although the COVID-19 pandemic led to increased distribution of VA-issued tablets to veterans with complex clinical and social needs, tablet recipients who were older or unstably housed remained less likely to have a video visit. The VA's tablet distribution program expanded access to video-enabled devices, but interventions are needed to bridge disparities in video visit use among device recipients.

Distribution of working hour characteristics by race, age, gender, and shift schedule among U.S. manufacturing workers

Shift work is a common occupational exposure, however, few studies have examined aspects of shift work beyond night work and long hours, such as rotational patterns or weekend work, which may contribute to poor health through disruption of the body's circadian rhythms. In this manuscript, we calculated the prevalence of working hour characteristics using algorithms for type (e.g., day), duration, intensity, rotational direction, and social aspects (e.g., weekend work) in a nationwide cohort of American manufacturing workers (N = 23,044) between 2003 and 2014. Distributions of working hour characteristics were examined by schedules (e.g., permanent day, day/night) and demographics, and were cross-classified in a matrix to examine co-occurrence. Approximately 55% of shifts may cause circadian rhythm disruption as they were non-day shifts or day shifts with a quick return or rotation, or were 13 h or longer. Older workers, female workers, and White workers worked permanent day shifts most often, while workers of color worked more day/night schedules. Night and evening shifts had more frequent shift rotations, quick returns, and longer hours than day shifts. Yet, day shifts, which are presumed to have little negative circadian impact, may cause circadian rhythm disruption as long hours, quick returns and rotations also occurred within day shifts.

The development and initial validation of a new working time scale for full-time workers with non-standard schedules

BACKGROUND

Working time characteristics have been used to link work schedule features to health impairment; however, extant working time exposure assessments are narrow in scope. Prominent working time frameworks suggest that a broad range of schedule features should be assessed to best capture non-standard schedules. The purpose of this study was to develop a multi-dimensional scale that assesses working time exposures and test its reliability and validity for full-time workers with non-standard schedules.

METHODS

A cross-sectional study was conducted using full-time, blue-collar worker population samples from three industries - transportation (n = 174), corrections (n = 112), and manufacturing (n = 99). Using a multi-phased approach including the review of scientific literature and input from an advisory panel of experts, the WorkTime Scale (WTS) was created and included multiple domains to characterize working time (length, time of day, intensity, control, predictability, and free time). Self-report surveys were distributed to workers at their workplace during company time. Following a comprehensive scale development procedure (Phase 1), exploratory factor analysis (EFA) (Phase 2) and, confirmatory factor analysis (CFA) (Phase 3; bivariate correlations were used to identify the core components of the WTS and assess the reliability and validity (Phase 4) in three samples.

RESULTS

Phase 1 resulted in a preliminary set of 21 items that served as the basis for the quantitative analysis of the WTS. Phase 2 used EFA to yield a 14-item WTS measure with two subscales ("Extended and Irregular Work Days (EIWD)" and "Lack of Control (LOC)"). Phase 3 used CFA to confirm the factor structure of the WTS, and its subscales demonstrated good internal consistency: alpha coefficients were 0.88 for the EIWD factor and 0.76-0.81 for the LOC factor. Phase 4 used bivariate correlations to substantiate convergent, discriminant, and criterion (predictive) validities.

CONCLUSIONS

The 14-item WTS with good reliability and validity is an effective tool for assessing working time exposures in a variety of full-time jobs with non-standard schedules.

Risk factors for antimicrobial resistance among Staphylococcus isolated from pets living with a patient diagnosed with methicillin-resistant Staphylococcus aureus infection

It has been suggested that pets play a critical role in the maintenance of methicillin-resistant (MR) and multidrug-resistant (MDR) Staphylococcus spp. in the household. We examined risk factors for carriage of antimicrobial-resistant coagulase-positive staphylococci, with particular attention to Staphylococcus aureus and Staphylococcus pseudintermedius isolated from pets living in households of people diagnosed with methicillin-resistant S. aureus (MRSA) skin or soft-tissue infection. We analyzed data collected cross-sectionally from a study conducted in 2012 that evaluated the transmission of MRSA and other staphylococci from humans, their pets and the environment (Pets and Environmental Transmission of Staphylococci [PETS] study). We used unadjusted and adjusted stratified logistic regression analyses with household-clustered standard errors to evaluate the association between demographic, healthcare-related, contact-related and environmental risk factors and MDR Staphylococcus spp. isolated from dogs and cats. Staphylococcal isolates obtained from dogs (n = 63) and cats (n = 47) were included in these analyses. The use of oral or injectable antimicrobials by the pets during the prior year was the main risk factor of interest. Based on our results, 50% (12/24) of S. aureus, 3.3% (1/30) of S. pseudintermedius and 25% (14/56) of other coagulase-positive staphylococci (CPS) were determined to be MDR. S. aureus isolates were more likely to be MDR compared with S. pseudintermedius. We did not find a significant statistical association between the use of oral or injectable antimicrobials in the prior year and the presence of MDR bacteria. The results suggest that drivers of antimicrobial resistance in household staphylococci may vary by bacterial species, which could have implications for one health intervention strategies for staphylococci and inform the investigation of other reverse zoonoses, such as COVID-19.

Racial and Ethnic Disparities in Cancer Care During the COVID-19 Pandemic

IMPORTANCE

The full effect of the COVID-19 pandemic on cancer care disparities, particularly by race and ethnicity, remains unknown.

OBJECTIVES

To assess whether the race and ethnicity of patients with cancer was associated with disparities in cancer treatment delays, adverse social and economic effects, and concerns during the COVID-19 pandemic and to evaluate trusted sources of COVID-19 information by race and ethnicity.

DESIGN, SETTING, AND PARTICIPANTS

This national survey study of US adults with cancer compared treatment delays, adverse social and economic effects, concerns, and trusted sources of COVID-19 information by race and ethnicity from September 1, 2020, to January 12, 2021.

EXPOSURES

The COVID-19 pandemic.

MAIN OUTCOMES AND MEASURES

The primary outcome was delay in cancer treatment by race and ethnicity. Secondary outcomes were duration of delay, adverse social and economic effects, concerns, and trusted sources of COVID-19 information.

RESULTS

Of 1639 invited respondents, 1240 participated (75.7% response rate) from 50 US states, the District of Columbia, and 5 US territories (744 female respondents [60.0%]; median age, 60 years [range, 24-92 years]; 266 African American or Black [hereafter referred to as Black] respondents [21.5%]; 186 Asian respondents [15.0%]; 232 Hispanic or Latinx [hereafter referred to as Latinx] respondents [18.7%]; 29 American Indian or Alaska Native, Native Hawaiian, or multiple races [hereafter referred to as other] respondents [2.3%]; and 527 White respondents [42.5%]). Compared with White respondents, Black respondents (odds ratio [OR], 6.13 [95% CI, 3.50-10.74]) and Latinx respondents (OR, 2.77 [95% CI, 1.49-5.14]) had greater odds of involuntary treatment delays, and Black respondents had greater odds of treatment delays greater than 4 weeks (OR, 3.13 [95% CI, 1.11-8.81]). Compared with White respondents, Black respondents (OR, 4.32 [95% CI, 2.65-7.04]) and Latinx respondents (OR, 6.13 [95% CI, 3.57-10.53]) had greater odds of food insecurity and concerns regarding food security (Black respondents: OR, 2.02 [95% CI, 1.34-3.04]; Latinx respondents: OR, 2.94 [95% CI, [1.86-4.66]), financial stability (Black respondents: OR, 3.56 [95% CI, 1.79-7.08]; Latinx respondents: OR, 4.29 [95% CI, 1.98-9.29]), and affordability of cancer treatment (Black respondents: OR, 4.27 [95% CI, 2.20-8.28]; Latinx respondents: OR, 2.81 [95% CI, 1.48-5.36]). Trusted sources of COVID-19 information varied significantly by race and ethnicity.

CONCLUSIONS AND RELEVANCE

In this survey of US adults with cancer, the COVID-19 pandemic was associated with treatment delay disparities and adverse social and economic effects among Black and Latinx adults. Partnering with trusted sources may be an opportunity to overcome such disparities.

Temporal Variation in Individual Social Risk Factors Associated with Testing Positive for SARS-CoV-2 Among Veterans in the Veterans Health Administration

PURPOSE

Marginalized communities have been disproportionally impacted by SARS-CoV-2. How the associations between social determinants of health and the risk of SARS-CoV-2 infection shifted across time is unknown. In this evaluation, we examine individual-level social determinants of health as social risk factors for SARS-CoV-2 infection across the first 12 months of the pandemic among US Veterans.

METHODS

We conducted a retrospective cohort analysis of 946,358 Veterans who sought testing or treatment for SARS-CoV-2 infection in U.S. Department of Veterans Affairs (VA) medical facilities. We estimated risk ratios for testing positive by social risk factors, adjusting for demographics, comorbidities, and time. Adjusted models were stratified by pandemic phase to assess temporal fluctuations in social risks.

RESULTS

Approximately 19% of Veterans tested positive for SARS-CoV-2. Larger household size was a persistent risk factor and this association increased over time. Early in the pandemic, lower county-level population density was associated with lower SARS-CoV-2 infection risk, but between June 1- August 31, 2020, this trend reversed.

CONCLUSIONS

Temporal fluctuations in social risks associated with Veterans' SARS-CoV-2 infection suggest the need for ongoing, real-time tracking as the social and medical environment continues to evolve.

Geographic and temporal variation in racial and ethnic disparities in SARS-CoV-2 positivity between February 2020 and August 2021 in the United States

The coronavirus pandemic has disproportionally impacted racial and ethnic minority communities in the United States. Patterns of these disparities may be changing over time as outbreaks occur in different communities. Utilizing electronic health record data from the US Department of Veterans Affairs (VA), we estimated odds ratios, stratified by time period and region, for testing positive among 1,313,402 individuals tested for SARS-CoV-2 between February 12, 2020 and August 16, 2021 at VA medical facilities. We adjusted for personal characteristics (sex, age, rural/urban residence, VA facility) and a wide range of clinical characteristics that have been evaluated in prior SARS-CoV-2 reports and could potentially explain racial/ethnic disparities in SARS-CoV-2. Our study found racial and ethnic disparities for testing positive were most pronounced at the beginning of the pandemic and decreased over time. A key finding was that the disparity among Hispanic individuals attenuated but remained elevated, while disparities among Asian individuals reversed by March 1, 2021. The variation in racial and ethnic disparities in SARS-CoV-2 positivity by time and region, independent of underlying health status and other demographic characteristics in a nationwide cohort, provides important insight for strategies to prevent further outbreaks.

The Impact of COVID-19 on Patients With Cancer: A National Study of Patient Experiences

OBJECTIVES

The coronavirus disease 2019 (COVID-19) pandemic abruptly disrupted cancer care. The impact of these disruptions on patient experiences remain relatively understudied. The objective of this study was to assess patients' perspectives regarding the impact of COVID-19 on their experiences, including their cancer care, emotional and mental health, and social determinants of health, and to evaluate whether these outcomes differed by cancer stage.

MATERIALS AND METHODS

We conducted a survey among adults with cancer across the United States from April 1, 2020 to August 26, 2020 using virtual snowball sampling strategy in collaboration with professional organizations, cancer care providers, and patient advocacy groups. We analyzed data using descriptive statistics, χ2 and t tests.

RESULTS

Three hundred twelve people with cancer participated and represented 38 states. The majority were non-Hispanic White (n=183; 58.7%) and female (n=177; 56.7%) with median age of 57 years. Ninety-one percent spoke English at home, 70.1% had health insurance, and 67% had access to home internet. Breast cancer was the most common diagnosis (n=67; 21.5%). Most had Stage 4 disease (n=80; 25.6%). Forty-six percent (n=145) experienced a change in their care due to COVID-19. Sixty percent (n=187) reported feeling very or extremely concerned that the pandemic would affect their cancer and disproportionately experienced among those with advanced cancer stages compared with earlier stages (P<0.001). Fifty-two percent (n=162) reported impact of COVID-19 on 1 or more aspects of social determinants of health with disproportionate impact among those with advanced cancer stages compared with earlier stages.

CONCLUSIONS

COVID-19 impacted the care and well-being of patients with cancer and this impact was more pronounced among people with advanced cancer stages. Future work should consider tailored interventions to mitigate the impact of COVID-19 on patients with cancer.

Changes in the associations of race and rurality with SARS-CoV-2 infection, mortality, and case fatality in the United States from February 2020 to March 2021: A population-based cohort study

BACKGROUND

We examined whether key sociodemographic and clinical risk factors for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection and mortality changed over time in a population-based cohort study.

METHODS AND FINDINGS

In a cohort of 9,127,673 persons enrolled in the United States Veterans Affairs (VA) healthcare system, we evaluated the independent associations of sociodemographic and clinical characteristics with SARS-CoV-2 infection (n = 216,046), SARS-CoV-2-related mortality (n = 10,230), and case fatality at monthly intervals between February 1, 2020 and March 31, 2021. VA enrollees had a mean age of 61 years (SD 17.7) and were predominantly male (90.9%) and White (64.5%), with 14.6% of Black race and 6.3% of Hispanic ethnicity. Black (versus White) race was strongly associated with SARS-CoV-2 infection (adjusted odds ratio [AOR] 5.10, [95% CI 4.65 to 5.59], p-value <0.001), mortality (AOR 3.85 [95% CI 3.30 to 4.50], p-value < 0.001), and case fatality (AOR 2.56, 95% CI 2.23 to 2.93, p-value < 0.001) in February to March 2020, but these associations were attenuated and not statistically significant by November 2020 for infection (AOR 1.03 [95% CI 1.00 to 1.07] p-value = 0.05) and mortality (AOR 1.08 [95% CI 0.96 to 1.20], p-value = 0.21) and were reversed for case fatality (AOR 0.86, 95% CI 0.78 to 0.95, p-value = 0.005). American Indian/Alaska Native (AI/AN versus White) race was associated with higher risk of SARS-CoV-2 infection in April and May 2020; this association declined over time and reversed by March 2021 (AOR 0.66 [95% CI 0.51 to 0.85] p-value = 0.004). Hispanic (versus non-Hispanic) ethnicity was associated with higher risk of SARS-CoV-2 infection and mortality during almost every time period, with no evidence of attenuation over time. Urban (versus rural) residence was associated with higher risk of infection (AOR 2.02, [95% CI 1.83 to 2.22], p-value < 0.001), mortality (AOR 2.48 [95% CI 2.08 to 2.96], p-value < 0.001), and case fatality (AOR 2.24, 95% CI 1.93 to 2.60, p-value < 0.001) in February to April 2020, but these associations attenuated over time and reversed by September 2020 (AOR 0.85, 95% CI 0.81 to 0.89, p-value < 0.001 for infection, AOR 0.72, 95% CI 0.62 to 0.83, p-value < 0.001 for mortality and AOR 0.81, 95% CI 0.71 to 0.93, p-value = 0.006 for case fatality). Throughout the observation period, high comorbidity burden, younger age, and obesity were consistently associated with infection, while high comorbidity burden, older age, and male sex were consistently associated with mortality. Limitations of the study include that changes over time in the associations of some risk factors may be affected by changes in the likelihood of testing for SARS-CoV-2 according to those risk factors; also, study results apply directly to VA enrollees who are predominantly male and have comprehensive healthcare and need to be confirmed in other populations.

CONCLUSIONS

In this study, we found that strongly positive associations of Black and AI/AN (versus White) race and urban (versus rural) residence with SARS-CoV-2 infection, mortality, and case fatality observed early in the pandemic were ameliorated or reversed by March 2021.

Working Time Characteristics and Mental Health among Corrections and Transportation Workers

OBJECTIVES

Mental health disorders are a leading cause of work disability and while the psychosocial workplace environment plays a critical role, working time characteristics are also implicated. We sought to examine the association between working time characteristics and mental health in a cohort of two unionized, full-time worker populations, correctional supervisors, and transportation maintainers.

METHODS

Using a cross-sectional study design, we surveyed workers on working time characteristics across seven domains including length of the shift, the intensity or proximity of sequential shifts, the time of day, and social aspects of work hours including predictability, variability, control, and free time. Burnout symptoms (Oldenburg Burnout Inventory) and depressive symptoms (eight-item Centers for Epidemiologic Studies Depression Scale) were assessed along with the psychosocial work environment and health behaviors. We used log-binomial regression models to estimate prevalence ratios and 95% confidence intervals after adjusting for age, gender, and company.

RESULTS

A total of 318 workers were surveyed. The majority (72%) of workers reported a fixed shift. The prevalence of burnout symptoms was higher among workers reporting more frequent shift intensity (working 6 or more days in a row) (PR: 1.15, 95% CI: 1.01, 1.31; P = 0.04). Low psychological demands and high worker social support were associated with fewer burnout symptoms, independent of working time characteristics. The prevalence of depressive symptoms was higher in workers reporting more frequent unpredictable work (PR: 1.17, 95% CI: 1.01, 1.35; P = 0.04) and was lower among workers reporting increased schedule control (PR: 0.86, 95% CI: 0.77, 0.96; P = 0.01). Higher worker social support as well as sufficient sleep and adequate exercise were associated with fewer depressive symptoms, independent of working time characteristics.

CONCLUSIONS

Different working time characteristics were associated with work-related mental health (i.e. burnout) as well as general mental health (i.e. depressive symptoms). Work intensity was associated with the prevalence of burnout symptoms and the results suggest that the mechanism may be through the need for recovery from the psychosocial exposures of work. Both schedule control and predictability were associated with depressive symptoms and the results suggest that work-life imbalance and lack of recovery may be implicated. Comprehensive prevention policies that consider work organization along with the psychosocial work environment and work-life balance may help to improve workers' mental health.

Organizational and External Factors Associated with Video Telehealth Use in the Veterans Health Administration Before and During the COVID-19 Pandemic

Objectives: To identify organizational and external factors associated with medical center video telehealth uptake (i.e., the proportion of patients using telemedicine) before and early in the coronavirus disease 2019 (COVID-19) pandemic. Materials and Methods: We conducted a retrospective, observational study using cross-sectional data for all 139 U.S. Veterans Affairs Medical Centers (VAMCs). We used logistic regression analyses to identify factors that predicted whether a VAMC was in the top quartile of VA Video Connect (VVC) telehealth uptake for primary care and mental health care. Results: All 139 VAMCs increased their VVC uptake at least 2-fold early in the pandemic, with most increasing uptake between 5- and 10-fold. Pre-COVID-19, higher VVC uptake in primary care was weakly and positively associated with having more high-risk patients, negatively associated with having more long-distance patients, and positively associated with the prior fiscal year's VVC uptake. During COVID-19, the positive association with high-risk patients and the negative association with long-distance patients strengthened, while weaker broadband coverage was negatively associated with VVC uptake. For mental health care, having more long-distance patients was positively associated with higher VVC uptake pre-COVID-19, but this relationship reversed during COVID-19. Discussion: Despite the marked increase in VVC uptake early in the COVID-19 pandemic, significant VAMC-level variation indicates that VVC adoption was more difficult for some medical centers, particularly those with poorer broadband coverage and less prior VVC experience. Conclusions and Relevance: These findings highlight opportunities for medical centers, VA Central Office, and other federal entities to ensure equitable access to video telehealth.

Differences in COVID-19 Testing and Test Positivity Among Veterans, United States, 2020

OBJECTIVE

COVID-19 disproportionately affects racial/ethnic minority groups in the United States. We evaluated characteristics associated with obtaining a COVID-19 test from the Veterans Health Administration (VHA) and receiving a positive test result for COVID-19.

METHODS

We conducted a retrospective cohort analysis of 6 292 800 veterans in VHA care at 130 VHA medical facilities. We assessed the number of tests for SARS-CoV-2 administered by the VHA (n = 822 934) and the number of positive test results (n = 82 094) from February 8 through December 28, 2020. We evaluated associations of COVID-19 testing and test positivity with demographic characteristics of veterans, adjusting for facility characteristics, comorbidities, and county-level area-based socioeconomic measures using nested generalized linear models.

RESULTS

In fully adjusted models, veterans who were female, Black/African American, Hispanic/Latino, urban, and low income and had a disability had an increased likelihood of obtaining a COVID-19 test, and veterans who were Asian had a decreased likelihood of obtaining a COVID-19 test. Compared with veterans who were White, veterans who were Black/African American (risk ratio [RR] = 1.23; 95% CI, 1.19-1.27) and Native Hawaiian/Other Pacific Islander (RR = 1.13; 95% CI, 1.05-1.21) had an increased likelihood of receiving a positive test result. Hispanic/Latino veterans had a 43% higher likelihood of receiving a positive test result than non-Hispanic/Latino veterans did.

CONCLUSIONS

Although veterans have access to subsidized health care at the VHA, the increased risk of receiving a positive test result for COVID-19 among Black and Hispanic/Latino veterans, despite receiving more tests than White and non-Hispanic/Latino veterans, suggests that other factors (eg, social inequities) are driving disparities in COVID-19 prevalence.

Virtual care expansion in the Veterans Health Administration during the COVID-19 pandemic: clinical services and patient characteristics associated with utilization

Objectives

To describe the shift from in-person to virtual care within Veterans Affairs (VA) during the early phase of the COVID-19 pandemic and to identify at-risk patient populations who require greater resources to overcome access barriers to virtual care.

Materials and Methods

Outpatient encounters (N = 42 916 349) were categorized by care type (eg, primary, mental health, etc) and delivery method (eg, in-person, video). For 5 400 878 Veterans, we used generalized linear models to identify patient sociodemographic and clinical characteristics associated with: 1) use of virtual (phone or video) care versus no virtual care and 2) use of video care versus no video care between March 11, 2020 and June 6, 2020.

Results

By June, 58% of VA care was provided virtually compared to only 14% prior. Patients with lower income, higher disability, and more chronic conditions were more likely to receive virtual care during the pandemic. Yet, Veterans aged 45–64 and 65+ were less likely to use video care compared to those aged 18–44 (aRR 0.80 [95% confidence interval (CI) 0.79, 0.82] and 0.50 [95% CI 0.48, 0.52], respectively). Rural and homeless Veterans were 12% and 11% less likely to use video care compared to urban (0.88 [95% CI 0.86, 0.90]) and nonhomeless Veterans (0.89 [95% CI 0.86, 0.92]).

Discussion

Veterans with high clinical or social need had higher likelihood of virtual service use early in the COVID-19 pandemic; however, older, homeless, and rural Veterans were less likely to have video visits, raising concerns for access barriers.

Conclusions and Relevance

While virtual care may expand access, access barriers must be addressed to avoid exacerbating disparities.

Investigating the relationship between working time characteristics on musculoskeletal symptoms: a cross sectional study

How working hours are organized can have a substantial effect on workers' health. Using a questionnaire and cross-sectional study design, we evaluated the relationship between working time characteristics, job demands, and health behaviors on musculoskeletal symptoms among 316 Department of Transportation (N = 174) and Department of Corrections (N = 142) workers. Low schedule control was associated with neck/shoulder musculoskeletal symptoms (prevalence ratio: 1.20, 95% confidence interval: 1.06-1.34, p < 0.01), and working long (>48 hours per week) hours more frequently was associated with leg/foot musculoskeletal symptoms (prevalence ratio: 1.26 95% confidence interval: 1.06-1.50, p = 0.02). Some working time characteristics were associated with musculoskeletal symptoms, and should be taken into consideration as part of interventions to prevent musculoskeletal disorders and promote health of workers.

Chronic obstructive pulmonary disease mortality: The Diesel Exhaust in Miners Study (DEMS)

BACKGROUND

Miners are highly exposed to diesel exhaust emissions from powered equipment. Although biologically plausible, there is little evidence based on quantitative exposure assessment, that long-term diesel exposure increases risk of chronic obstructive pulmonary disease (COPD). To fill this gap, we examined COPD mortality and diesel exhaust exposure in the Diesel Exhaust in Miners Study (DEMS).

METHODS

We fit Cox models to estimate hazard ratios (HRs) for COPD mortality and cumulative exposure (μg/m³-years) to respirable elemental carbon (REC), a key metric for diesel exhaust exposure. Separate models were fit for ever-underground and surface-only miners to allow for effect modification. Exposure was lagged by 0, 10 and 15 years. In a secondary analysis, we addressed the healthy worker survivor effect by applying the parametric g-formula to handle time-varying confounding affected by prior exposure among ever-underground workers.

RESULTS

Based on 140 cases, the HRs for COPD mortality increased as categories of lagged REC exposure increased for all workers. Among surface-only workers, those in the middle exposure category (0 lag) had a significantly elevated hazard ratio of 2.34 (95% CI: 1.11-4.61) relative to those in the lowest category. Among the ever-underground, that ratio was 1.35, with wide confidence intervals. Using the g-formula, we estimated that the lifetime cumulative risk of COPD mortality would have been reduced from the observed 5.0%-3.1% under a hypothetical intervention where all ever-underground workers were always unexposed.

CONCLUSIONS

Our results suggest long term exposure to diesel exhaust may increase risk of COPD in miners, though power was limited.

Biomarkers of Secondhand Smoke Exposure in Waterpipe Tobacco Venue Employees in Istanbul, Moscow, and Cairo

Background

Most smoke-free legislation to reduce secondhand smoke (SHS) exposure exempts waterpipe (hookah) smoking venues. Few studies have examined SHS exposure in waterpipe venues and their employees.

Methods

We surveyed 276 employees of 46 waterpipe tobacco venues in Istanbul, Moscow, and Cairo. We interviewed venue managers and employees and collected biological samples from employees to measure exhaled carbon monoxide (CO), hair nicotine, saliva cotinine, urine cotinine, urine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), and urine 1-hydroxypyrene glucuronide (1-OHPG). We estimated adjusted geometric mean ratios (GMR) of each SHS biomarker by employee characteristics and indoor air SHS measures.

Results

There were 73 nonsmoking employees and 203 current smokers of cigarettes or waterpipe. In nonsmokers, the median (interquartile) range concentrations of SHS biomarkers were 1.1 (0.2, 40.9) µg/g creatinine urine cotinine, 5.5 (2, 15) ng/mL saliva cotinine, 0.95 (0.36, 5.02) ng/mg hair nicotine, 1.48 (0.98, 3.97) pg/mg creatinine urine NNAL, 0.54 (0.25, 0.97) pmol/mg creatinine urine 1-OHPG, and 1.67 (1.33, 2.33) ppm exhaled CO. An 8-hour increase in work hours was associated with higher urine cotinine (GMR: 1.68, 95% CI: 1.20, 2.37) and hair nicotine (GMR: 1.22, 95% CI: 1.05, 1.43). Lighting waterpipes was associated with higher saliva cotinine (GMR: 2.83, 95% CI: 1.05, 7.62).

Conclusions

Nonsmoking employees of waterpipe tobacco venues were exposed to high levels of SHS, including measurable levels of carcinogenic biomarkers (tobacco-specific nitrosamines and PAHs).

Implications

Smoke-free regulation should be extended to waterpipe venues to protect nonsmoking employees and patrons from the adverse health effects of SHS.

Night and rotational work exposure within the last 12 months and risk of incident hypertension

Objectives Shift work, such as alternating day and nights, causes chronobiologic disruptions which may cause an increase in hypertension risk. However, the relative contributions of the components of shift work ‒ such as shift type (eg, night work) and rotations (ie, switching of shift times; day to night) ‒ on this association are not clear. To address this question, we constructed novel definitions of night work and rotational work and assessed their associations with risk of incident hypertension. Methods A cohort of 2151 workers at eight aluminum manufacturing facilities previously studied for cardiovascular disease was followed from 2003 through 2013 for incident hypertension, as defined by ICD-9 insurance claims codes. Detailed time-registry data was used to classify each worker's history of rotational and night work. The associations between recent rotational work and night work in the last 12 months and incident hypertension were estimated using adjusted Cox proportional hazards models. Results Elevated hazard ratios (HR) were observed for all levels of recent night work (>0-5, >5-50, >50-95, >95-100%) compared with non-night workers, and among all levels of rotational work (<1, 1-10, >10-20, >20-30, and >30%) compared with those working <1% rotational work. In models for considering the combination of night and rotational work, workers with mostly night work and frequent rotations (≥50% night and ≥10% rotation) had the highest risk of hypertension compared to non-night workers [HR 4.00, 95% confidence interval (CI )1.69-9.52]. Conclusions Our results suggest recent night and rotational work may both be associated with higher rates of incident hypertension.

Comparison of High Purity Factor IX Concentrates and a Prothrombin Complex Concentrate in a Canine Model of Thrombogenicity

A non-stasis canine model of thrombogenicity has been used to evaluate batches of high purity factor IX concentrates from 4 manufacturers and a conventional prothrombin complex concentrate (PCC). Platelets, activated partial thromboplastin time (APTT), fibrinogen, fibrin(ogen) degradation products and fibrinopeptide A (FPA) were monitored before and after infusion of concentrate. Changes in FPA were found to be the most sensitive and reproducible indicator of thrombogenicity after infusion of batches of the PCC at doses of between 60 and 180 IU/kg, with a dose related delayed increase in FPA occurring. Total FPA generated after 100-120 IU/kg of 3 batches of PCC over the 3 h time course was 9-12 times that generated after albumin infusion. In contrast the amounts of FPA generated after 200 IU/kg of the 4 high purity factor IX products were in all cases similar to albumin infusion. It was noted that some batches of high purity concentrates had short NAPTTs indicating that current in vitro tests for potential thrombogenicity may be misleading in predicting the effects of these concentrates in vivo.

The Healthy Worker Survivor Effect: Target Parameters and Target Populations

PURPOSE OF REVIEW

We offer an in-depth discussion of the time-varying confounding and selection bias mechanisms that give rise to the healthy worker survivor effect (HWSE).

RECENT FINDINGS

In this update of an earlier review, we distinguish between the mechanisms collectively known as the HWSE and the statistical bias that can result. This discussion highlights the importance of identifying both the target parameter and the target population for any research question in occupational epidemiology. Target parameters can correspond to hypothetical workplace interventions; we explore whether these target parameters' true values reflect the etiologic effect of an exposure on an outcome or the potential impact of enforcing an exposure limit in a more realistic setting. If a cohort includes workers hired before the start of follow-up, HWSE mechanisms can limit the transportability of the estimates to other target populations. We summarize recent publications that applied g-methods to control for the HWSE, focusing on their target parameters, target populations, and hypothetical interventions.

Mathematical Modeling and Evaluation of Human Motions in Physical Therapy Using Mixture Density Neural Networks

OBJECTIVE

The objective of the proposed research is to develop a methodology for modeling and evaluation of human motions, which will potentially benefit patients undertaking a physical rehabilitation therapy (e.g., following a stroke or due to other medical conditions). The ultimate aim is to allow patients to perform home-based rehabilitation exercises using a sensory system for capturing the motions, where an algorithm will retrieve the trajectories of a patient's exercises, will perform data analysis by comparing the performed motions to a reference model of prescribed motions, and will send the analysis results to the patient's physician with recommendations for improvement.

METHODS

The modeling approach employs an artificial neural network, consisting of layers of recurrent neuron units and layers of neuron units for estimating a mixture density function over the spatio-temporal dependencies within the human motion sequences. Input data are sequences of motions related to a prescribed exercise by a physiotherapist to a patient, and recorded with a motion capture system. An autoencoder subnet is employed for reducing the dimensionality of captured sequences of human motions, complemented with a mixture density subnet for probabilistic modeling of the motion data using a mixture of Gaussian distributions.

RESULTS

The proposed neural network architecture produced a model for sets of human motions represented with a mixture of Gaussian density functions. The mean log-likelihood of observed sequences was employed as a performance metric in evaluating the consistency of a subject's performance relative to the reference dataset of motions. A publically available dataset of human motions captured with Microsoft Kinect was used for validation of the proposed method.

CONCLUSION

The article presents a novel approach for modeling and evaluation of human motions with a potential application in home-based physical therapy and rehabilitation. The described approach employs the recent progress in the field of machine learning and neural networks in developing a parametric model of human motions, by exploiting the representational power of these algorithms to encode nonlinear input-output dependencies over long temporal horizons.

Hepatic epithelioid haemangioendothelioma: challenges in diagnosis and management

BACKGROUND

  Hepatic epithelioid haemangioendothelioma (HEH) is a rare, low grade malignant neoplasm of endothelial origin which is difficult to diagnose and has a variable outcome. We review five HEH cases from our centre with the aim of identifying clinical predictors of outcome and various therapeutic options.

METHODS

  A search was made on the WA Liver Transplant registry for cases with histologically confirmed HEH. Their medical records were reviewed. A literature search was conducted through Medline using terms to compare the results from this series with those of other series.

RESULTS

  Five patients were identified to have HEH. The mean age was 44.2years (range 34-53years). Four of five patients presented with dyspepsia and two patients had clinical evidence of portal hypertension with ascites. Two patients had radiologically diffuse disease and three patients had discrete nodular liver involvement. The mean duration from presentation of symptoms to diagnosis of HEH was 26.8months. Liver transplantation was performed in one patient with diffuse HEH who is alive with no disease recurrence at 3years. Three patients with radiologically stable disease followed with 6monthly surveillance imaging are currently alive and well. The median survival of all five patients was 5years (range 1.5-16years) at the time of follow up.

CONCLUSIONS

  These results support the role of surveillance alone for patients with focal and radiologically stable disease. Patients with diffuse HEH with hepatic decompensation should be considered for transplantation. However, numbers are small and an international registry is required to make firm comparisons.

Modeling pathogenesis of Huntington's disease with inducible neuroprogenitor cells

Huntington's disease (HD) is caused by an abnormal expansion of CAG trinucleotide repeats encoding polyglutamine (polyQ) in the first exon of the huntingtin (htt) gene. Despite considerable efforts, the pathogenesis of HD remains largely unclear due to a paucity of models that can reliably reproduce the pathological characteristics of HD. Here, we report a neuronal cell model of HD using the previously established tetracycline regulated rat neuroprogenitor cell line, HC2S2. Stable expression of enhanced green fluorescence protein tagged htt exon 1 (referred to as 28Q and 74Q, respectively) in the HC2S2 cells did not affect rapid neuronal differentiation. However, compared to the cells expressing wild type htt, the cell line expressing mutant htt showed an increase in time-dependent cell death and neuritic degeneration, and displayed increased vulnerability to oxidative stress. Increased protein aggregation during the process of neuronal aging or when the cells were exposed to oxidative stress reagents was detected in the cell line expressing 74Q but not in its counterpart. These results suggest that the neuroprogenitor cell lines mimic the major neuropathological characteristics of HD and may provide a useful tool for studying the neuropathogenesis of HD and for high throughput screening of therapeutic compounds.

Effects of reboxetine on Hamilton Depression Rating Scale factors from randomized, placebo-controlled trials in major depression

Reboxetine is the first selective norepinephrine reuptake inhibitor (NRI) approved for the treatment of major depressive disorder (MDD). Although reboxetine has demonstrated efficacy for the treatment of depression, its effects on specific depressive symptoms have not been reported. We evaluated the effects of reboxetine on four Hamilton Depression Rating Scale (HAM-D) factors: psychomotor retardation, anxiety, cognitive disturbance and insomnia. Data were obtained from four short-term (4-8-week), randomized, placebo-controlled trials of reboxetine for the treatment of MDD. For each study, mean changes in HAM-D symptom factor scores from randomization to the study endpoint were compared between reboxetine and placebo. In addition, data from all four studies were pooled to determine the proportions of patients who either improved or worsened with treatment were compared between placebo (n = 353) and reboxetine (n = 350) treatment groups. Compared to placebo, reboxetine significantly improved psychomotor retardation in all four trials. Cognitive disturbance and anxiety were improved in three of four trials, and insomnia was improved in one trial with a positive trend in the second trial. Reboxetine, a selective NRI, improves symptoms of psychomotor retardation, anxiety and cognitive disturbance during treatment of MDD.

Influence of the severity of cognitive impairment on the effect of the Gnkgo biloba extract EGb 761 in Alzheimer's disease

OBJECTIVE

To explore the treatment effect of EGb 761((R)) (EGb) in Alzheimer's disease depending on baseline severity.

METHODS

We applied stratification to the intent-to-treat data set collected during a 52-week, randomized, double-blind, placebo-controlled, parallel-group, multicenter study with 120 mg of EGb, using cutoff points of 23 and 14 for the Mini-Mental State Examination (MMSE) score. Outcome measures used were the cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-Cog) and the Geriatric Evaluation by Relative's Rating Instrument (GERRI).

RESULTS

In the severity stratum 1 (MMSE >23), the placebo group did not show significant changes, while the EGb group improved significantly by 1.7 points on the ADAS-Cog and by 0.09 points on the GERRI. In the severity stratum 2 (MMSE <24), the placebo group worsened by 4.1 points on the ADAS-Cog and 0.18 points on the GERRI, whereas the EGb group showed 60% less decline on the ADAS-Cog (treatment difference of 2.5 points) and no change on the GERRI (treatment difference of 0.25 points). The most severely impaired subgroup (MMSE <15) showed slightly more pronounced worsening for both treatment groups. However, in comparison to placebo, EGb induced virtually the same magnitude of effect as was observed in the entire stratum 2.

CONCLUSIONS

The results of this retrospective analysis indicated that a treatment effect favorable to EGb could be observed with respect to cognitive performance (p = 0.02) and social functioning (p = 0.001) regardless of the stage of dementia, whether mild or moderately severe. However, the relative changes from baseline measured at endpoint depended heavily on the severity at baseline. Improvement was observed in the group of patients with very mild to mild cognitive impairment, while in more severe dementia, the mean EGb effect should be considered more in terms of stabilization or slowing down of worsening, as compared to the greater deterioration observed with placebo.

The effects of antidepressants on sexual functioning in depressed patients: a review

Sexual dysfunction has long been noted as both a symptom of depressive illness and as a side effect of many of the medications used to treat depression. Although most people suffering from a major depressive illness would like to be sexually active, half experience a decrease in desire or sexual performance. Antidepressant medications often interfere with several parts of the sexual response. This review compares data from different types of research into the effect of antidepressant medications on the sexual response: case reports, chart reviews, and single- and double-blind studies with and without active control medications. From this review, it is clear that antidepressants of most classes interfere with human sexual functioning, with the notable exceptions of bupropion and nefazodone.

Reemergence of sexual dysfunction in patients with major depressive disorder: double-blind comparison of nefazodone and sertraline

BACKGROUND

Several different classes of antidepressants have been associated with sexual adverse effects. This double-blind, randomized trial compared the effects of nefazodone and sertraline on reemergence of sexual dysfunction in depressed patients who had experienced sexual dysfunction as a result of sertraline treatment. Depressive symptoms were also monitored.

METHOD

One hundred five patients with DSM-III-R major depressive episode who were experiencing sexual dysfunction attributable to sertraline (100 mg/day) were screened for entry. Eligible patients entered a 1-week washout period that was followed by a 7- to 10-day single-blind placebo phase. Patients without symptoms of sexual dysfunction at the end of the single-blind placebo phase were randomly assigned to receive double-blind treatment with either nefazodone (400 mg/day) or sertraline (100 mg/day) for 8 weeks.

RESULTS

Nearly 3 times more sertraline-treated patients (76%; 25/33) experienced reemergence of sexual dysfunction (ejaculatory and/or orgasmic difficulty) than did nefazodone-treated patients (26%; 10/39) (p < .001). In addition, patients treated with nefazodone were more satisfied with their sexual functioning than were patients treated with sertraline. Both treatment groups demonstrated a similar and sustained improvement in depressive symptoms. Both drugs were well tolerated, and the overall incidence of adverse reactions was similar for both treatment groups; however, 9 sertraline-treated patients (26%) discontinued because of adverse events compared with 5 nefazodone-treated patients (12%). Of the patients discontinuing therapy for adverse events, 5 of the sertraline-treated patients did so because of sexual dysfunction reported as an adverse event, whereas only 1 of the nefazodone-treated patients discontinued therapy secondary to sexual dysfunction.

CONCLUSION

In this sample of patients with major depression who had recovered from sexual dysfunction induced by treatment with sertraline, nefazodone treatment resulted in significantly less reemergence of sexual dysfunction than did renewed treatment with sertraline and provided continued antidepressant activity.

A 24-week randomized trial of controlled-release physostigmine in patients with Alzheimer's disease

OBJECTIVE

To evaluate the safety and efficacy of controlled-release physostigmine, an acetylcholinesterase inhibitor, in patients with probable AD of mild to moderate severity.

METHODS

A prospective, 24-week, randomized, multicenter, double-blind, parallel group study of patients was conducted. The study enrolled 475 patients at 24 sites. Patients met criteria for probable AD and were randomized to one of three arms: placebo, controlled-release (CR) physostigmine 30 mg daily, or CR physostigmine 36 mg daily. Dosage was escalated by a forced upward titration during the first 6 to 9 weeks of the trial, then maintained at a constant dose to 24 weeks. Primary outcome measures were the Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) and the Clinician's Interview-Based Impression of Change-Plus with caregiver input (CIBIC+). Secondary outcome measures included the Clinical Global Impression of Change (CGIC), the Geriatric Evaluation by Relatives Rating Instrument, and an Instrumental Activities of Daily Living Scale.

RESULTS

In an intent-to-treat population, the last observation carried forward analysis revealed a 2.9-point ADAS-Cog (p = 0.002) difference between physostigmine and placebo-treated patients for both dosages, and a 0.26 to 0.31-point difference on the CIBIC+ (p = 0.048). There were no significant differences on the secondary outcome measures except for a difference on the CGIC when analyzed by use of the Cochran-Mantel-Haenszel statistic (p = 0.014). There were significant increases in gastrointestinal side effects including nausea, vomiting, diarrhea, anorexia, dyspepsia, and abdominal pain for patients on either dose of physostigmine, resulting in a high dropout rate. Agitation was decreased significantly. There was no evidence of cardiac rhythm disturbance or liver function abnormalities.

CONCLUSION

CR physostigmine enhanced cognitive and global function. It is relatively safe for the treatment of cognitive dysfunction secondary to AD. However, in light of the gastrointestinal side effects, a lower starting dose and a flexible titration schedule might lead to a more favorable adverse event profile in the clinical arena.

Sibutramine produces dose-related weight loss

OBJECTIVE

Sibutramine is a weight control drug that inhibits the reuptake of both serotonin and norepinephrine. In animals, it reduces food intake and increases thermogenesis and preliminary data in human beings showed weight loss. This paper reports a 24-week dose-ranging study to determine the effect of sibutramine on body weight of patients with obesity.

RESEARCH METHODS AND PROCEDURES

Seven clinical centers screened 1463 patients with obesity and randomized 1047 to 24 weeks of treatment with 1 of 6 doses of sibutramine (1, 5, 10, 15, 20, or 30 mg) or placebo once daily. Six hundred eighty-three patients completed the study. A two-week placebo run-in period was used to initiate a standardized program of diet, physical activity, and lifestyle changes.

RESULTS

Weight loss was dose-related and statistically significant vs. placebo (p<0.05) across all time-points for a 5 mg/day to 30 mg/day dosage of sibutramine. At week 24, percent weight loss from baseline for completers was: placebo, 1.2%; 1 mg, 2.7%; 5 mg, 3.9%; 10 mg, 6.1%; 15 mg, 7.4%; 20 mg, 8.8%; and 30 mg, 9.4%. Weight loss achieved at week 4 was predictive of weight loss achieved at week 24. Patients losing weight demonstrated an increase in serum high density lipoprotein cholesterol and reductions in serum triglycerides, total cholesterol, low density lipoprotein cholesterol, and uric acid. Small mean increases in blood pressure and pulse rate (with considerable individual variability) were observed in patients treated with sibutramine. The most frequent adverse events were dry mouth, anorexia, and insomnia.

DISCUSSION

Sibutramine administered once daily for 24 weeks in the weight loss phase of treatment for uncomplicated obesity produced dose-related weight loss and was well tolerated. Improvements in serum lipids and uric acid accompany sibutramine-induced weight loss. Most of the adverse events observed on sibutramine are related to its pharmacology, including small mean increases in blood pressure and heart rate.

Acute pulmonary embolism: diagnosis with MR angiography

PURPOSE

To prospectively evaluate pulmonary magnetic (MR) angiography as a diagnostic examination for acute pulmonary embolism (PE).

MATERIALS AND METHODS

Thirty-six consecutive patients (19 women, 17 men; age range, 28-84 years) underwent pulmonary digital subtraction angiography (DSA) and pulmonary MR angiography. MR angiograms were obtained during suspended respiration and the pulmonary arterial phase of gadolinium-based contrast medium injection. A steady-state gradient-recalled-echo sequence with free induction decay sampling was used. DSA studies were interpreted for the presence of acute PE by two independent radiologists; an adjudicator made the final decision on discordant interpretations.

RESULTS

By using DSA, a total of 19 acute pulmonary emboli were depicted in 13 patients. Prospectively, 13 of these emboli were depicted by using MR angiography. MR angiography missed six emboli: Four required the DSA adjudicator to make the decision, and one was in a patient whose MR angiogram was acquired during breathing. Four of these six emboli were small subsegmental emboli, and two were segmental.

CONCLUSION

Performed without pulmonary arterial catheterization, iodinated contrast media, or ionizing radiation, pulmonary MR angiography had a high accuracy for depicting lobar and segmental emboli, but was unable to depict four of five subsegmental emboli.

The crystal structure of citrate synthase from the hyperthermophilic archaeon pyrococcus furiosus at 1.9 A resolution,

The crystal structure of the closed form of citrate synthase, with citrate and CoA bound, from the hyperthermophilic Archaeon Pyrococcus furiosus has been determined to 1.9 A. This has allowed direct structural comparisons between the same enzyme from organisms growing optimally at 37 degrees C (pig), 55 degrees C (Thermoplasma acidophilum) and now 100 degrees C (Pyrococcus furiosus). The three enzymes are homodimers and share a similar overall fold, with the dimer interface comprising primarily an eight alpha-helical sandwich of four antiparallel pairs of helices. The active sites show similar modes of substrate binding; moreover, the structural equivalence of the amino acid residues implicated in catalysis implies that the mechanism proceeds via the same acid-base catalytic process. Given the overall structural and mechanistic similarities, it has been possible to make detailed structural comparisons between the three citrate synthases, and a number of differences can be identified in passing from the mesophilic to thermophilic to hyperthermophilic citrate synthases. The most significant of these are an increased compactness of the enzyme, a more intimate association of the subunits, an increase in intersubunit ion pairs, and a reduction in thermolabile residues. Compactness is achieved by the shortening of a number of loops, an increase in the number of atoms buried from solvent, an optimized packing of side chains in the interior, and an absence of cavities. The intimate subunit association in the dimeric P. furiosus enzyme is achieved by greater complementarity of the monomers and by the C-terminal region of each monomer folding over the surface of the other monomer, in contrast to the pig enzyme where the C-terminus has a very different fold. The increased number of intersubunit ion pairs is accompanied by an increase in the number involved in networks. Interestingly, all loop regions in the P. furiosus enzyme either are shorter or contain additional ion pairs compared with the pig enzyme. The possible relevance of these structural features to enzyme hyperthermostability is discussed.

The effect of added-purpose and meaningful occupation on motor learning

OBJECTIVE

Numerous studies in the occupational therapy literature have investigated the effects of added-purpose (multidimensional, goal-oriented) occupation on performance. Motor learning research has demonstrated that factors that enhance performance measures do not necessarily enhance motor learning. This study examined the effects of both added-purpose and meaningful occupation on motor learning.

METHOD

Twenty subjects (university students) were randomly assigned to either an added-purpose or rote exercise condition. After a skill acquisition phase, retention and transfer scores were obtained, and subjects were asked to rate the meaningfulness of the occupation on a visual analog scale.

RESULTS

A two-way analysis of variance indicated that only the added-purpose occupation resulted in significantly greater motor learning. Additionally, the added-purpose scores were not influenced by the level of meaning assigned to the occupation.

CONCLUSION

This study is the first to demonstrate how added-purpose can enhance a more permanent aspect of performance: motor learning. Further research is necessary to determine whether occupations that both are meaningful and have added-purpose are the most effective in enhancing motor learning.

Complete pre-operative imaging assessment of abdominal aortic aneurysm with spiral CT angiography

PURPOSE

A prospective evaluation of spiral CT angiography (SCTA) as the sole pre-operative imaging modality for abdominal aortic aneurysm repair.

MATERIALS AND METHODS

Spiral CT angiography was compared with conventional transfemoral angiography in 30 patients and results correlated with surgical findings in 22 patients. The following features were assessed: renal artery number and disease; upper and lower aneurysm extent; aneurysm size; perianeurysmal inflammation; iliac artery disease; radiation dose; and contrast usage.

RESULTS

Spiral CT angiography agreed with conventional angiography in all cases of severe stenosis or occlusion of renal arteries and had 90% agreement overall for renal artery disease. Two of nine accessory renal arteries seen at conventional angiography were missed. For showing aneurysm extent SCTA was 100% sensitive, and performed better than conventional angiography. Aneurysm size was better shown with SCTA. In iliac disease SCTA, as performed in this study, was poor for mild-moderate disease, but detected four of six severely stenosed/occluded iliac arteries seen at conventional angiography. Prospective sensitivity for perianeurysmal inflammation was 33%. Radiation dose for SCTA was approximately twice and contrast dose approximately three times that for conventional angiography.

CONCLUSION

Spiral CT angiography can provide all the necessary imaging information to plan aneurysm repair in the non-claudicant.

Transhepatic venous angioplasty and stenting: a treatment option in bleeding from gastric varices secondary to pancreatic carcinoma

We present a case of recurrent variceal bleeding due to subtotal occlusion of the splenoportal junction by a pancreatic carcinoma. This was effectively treated by transhepatic venous angioplasty and stenting.

Endovascular surgery

The procedures used in the treatment of peripheral arterial disease are evolving constantly. The most rapid changes have been in the use of endovascular techniques in which the interventions are occurring from within the blood vessel either in the radiology suite percutaneously or in the operating theatre by open access. The following article attempts to bring together these two disciplines and to address them with a unified approach.

Percutaneous varicocele embolization in the treatment of infertility

Clinical and sub-clinical varicoceles are associated with infertility and abnormal sperm parameters. Percutaneous embolization is a minimally invasive, safe, outpatient method of treatment which is cost effective in comparison to surgery. This study is a retrospective review of embolization of the spermatic vein using stainless steel occluding spring coils, performed in 116 males from two infertility clinics. Follow-up results were complete in 87 patients of which 79 (91%) were successful both technically and clinically and all had sperm analysis performed both before and within 2 years after embolization. There was a highly significant increase in motility (mean 35% before, mean 46% after, p < 0.001). Sperm density showed a trend towards improvement, but only p < 0.10, and there was no significant change in semen volume or morphology. The partners of 29 men (33%) became pregnant in a total of 241 years of follow-up.

The role of duplex and colour Doppler ultrasound in the follow-up evaluation of transjugular intrahepatic portosystemic stent shunt (TIPSS)

Transjugular intrahepatic portosystemic stent shunt (TIPSS) is an effective means of controlling acute variceal haemorrhage. Shunt occlusion or stenosis occurs in up to 30% of patients within 6 months. It is important to detect these patients and intervene to prevent rebleeding. We have compared non-invasive Doppler ultrasound with the portal pressure gradient (PPG) at portography at 3 month follow-up in 23 patients. All patients with a shunt peak velocity greater than 90 cm s-1 (7 of 17 analysable results) had normal shunt function at portography (PPG < 12 mmHg). Portography may therefore be avoided in this group, although the majority of patients will still require portography for TIPSS follow-up assessment.

Case report: computed tomography features of complete splenic infarction, cavitation and spontaneous decompression complicating pancreatitis

Splenic infarction is a rare complication of pancreatitis. We present the case of a 34-year-old woman, who had undergone previous drainage of a pancreatic pseudocyst, and who represented with left upper quadrant pain. Absence of enhancement of the splenic parenchyma during contrast enhanced computed tomography (CT) allowed confident diagnosis of complete splenic infarction. A later CT scan revealed splenic cavitation with spontaneous decompression into the stomach. The aetiology of these unusual complications of pancreatitis is discussed.

Intracranial meningioma with hepatic metastases and hypoglycaemia treated by selective hepatic arterial chemo-embolization

Meningiomas rarely give rise to metastases despite frequent dural invasion. A rare case of symptomatic hypoglycaemia due to extensive liver metastases from an angioblastic meningioma is described along with the use of hepatic arterial chemo-embolization to effect palliation by reduction in tumour bulk.

Dothiepin versus doxepin in major depression: results of a multicenter, placebo-controlled trial. Prothiaden Collaborative Study Group

BACKGROUND

The tricyclic antidepressant dothiepin is well established in Europe, but clinical experience with the drug in the United States is limited.

METHOD

In a 10-week, multicenter, randomized, double-blind, placebo-controlled study in the United States, the efficacy and tolerability of dothiepin and doxepin (both administered as a 150-mg nightly dose) were compared in 579 outpatients with major depression.

RESULTS

Patients in both active treatment groups showed significant improvements in depressive symptoms, associated anxiety, and sleep parameters compared with the placebo-treated group. The adverse effect profile of dothiepin was superior to that of doxepin, particularly with respect to drowsiness, weight gain, and increased appetite.

CONCLUSION

These results confirm that dothiepin is useful when a tricyclic agent is indicated for the treatment of depression.

The use of electroconvulsive therapy in patients with intractable anorexia nervosa

The history of the treatment of anorexia nervosa includes the majority of psychological and somatic therapies devised by psychiatrists, psychologists, and general physicians. We review the history of one of these treatments, electrical convulsive therapy (ECT), and discuss three patients treated with ECT for primary anorexia nervosa. Two had a positive response to this treatment, one did not. She later responded favorably to a course of treatment with fluoxetine.

Problems associated with ultrasonography of the canine ovary around the time of ovulation

Real-time B-mode ultrasound imaging was carried out, using a scanner of moderate quality, on 40 fresh bitch cadavers to identify the presence of ovaries and significant ovarian structures. The results indicated that accurate identification of the ovaries depended on the presence of significant follicles or corpora lutea (CL). The findings were verified at post-mortem examination. The study was continued by scanning 35 live bitches using three different scanning units of increasingly improved quality to show that the process of ovulation could be assessed with reasonable accuracy with improved quality of equipment, although the exact fate of the follicle could not be imaged. The results were judged against assays for blood circulating progesterone. A final group of seven live bitches were scanned with a high-grade scanner using an annular phased-array transducer to attempt to image the process of ovulation. The non-echogenic follicle disappeared and was replaced by the CL that was hypoechoic with respect to surrounding tissue, thus allowing accurate assessment of the time of ovulation. This was confirmed by progesterone assay.