Demographic Representation in Clinical Trials Sponsored by the United States Department of Veterans Affairs

PURPOSE/OBJECTIVE(S)

Non-White racial and ethnic groups remain underrepresented in oncology clinical trials within the United States and face ongoing barriers to participation. Previous reports cite positive attitudes toward clinical trials (CTs) among veterans, with altruism and a strong sense of community posited as driving forces for participation. Our objective was to characterize demographic representation among CTs sponsored by the U.S. Department of Veterans Affairs (VA) and U.S. Department of Defense (DoD) compared to trials with no VA/DoD sponsorship.

MATERIALS/METHODS

We incorporated data from U.S. CTs registered in ClinicalTrials.gov between March 2000 and March 2020 using the Aggregate Analysis of ClinicalTrials.gov database, and stratified CTs by sponsorship into the following groups: (1) VA, (2) DoD or (3) non-VA/DoD sponsorship. We extracted CT enrollment data for gender and four race/ethnicity categories: White, Hispanic/Latinx, Black, and Asian. After calculating gender and race-specific proportions for each CT, we compared the median proportion of White, non-White, Black, Asian, and Hispanic participants between (a) VA and non-VA/DoD CTs, (b) DoD and non-VA/DoD CTs, and (c) VA CTs and the Veterans Health Agency (VHA) patient population using Wilcoxon signed rank tests.

RESULTS

This study included 13942 CTs; of these, 490 (94%) VA, 38 (95%) DoD, and 12574 (95%) non-VA/DoD sponsored CTs reported race/ethnicity data. Non-VA/DoD entities sponsored a greater relative number of oncology CTs (29%) than did the VA (5%) or DoD (3%). Characterization of CTs by participant race/ethnicity demonstrated median non-White enrollment was 68% greater in VA CTs (p<0.001) and 34% greater in DoD CTs (p = 0.138) than non-VA/DoD CTs. Increased non-White VA CT enrollment was driven largely by the higher median proportion of Black participants (24%)-more than double that of non-VA/DoD CTs (10%) (Table 1). Comparison between the median proportion of Black participants in VA CTs and VHA patient demographics (15.8% Black) revealed that VA CTs enroll a greater percentage of Black participants than reflected in the VHA patient population (p<0.001).

CONCLUSION

This characterization of veteran involvement in CTs demonstrates that VA sponsored CTs feature significantly greater representation of minorities, a pattern driven exclusively by greater enrollment of black patients. This work prompts further exploration into modeling VA enrollment strategies in non-VA CTs and increasing VA sponsorship of cancer trials to stimulate inclusion of underrepresented populations in oncology CTs.

USA Department of Defense audit of surgical antibiotic prophylaxis prescribing patterns in inguinal hernia repair

PURPOSE

Antibiotic prophylaxis in inguinal hernia repair (IHR) is contentious in literature and practice. In low-risk patients, for whom evidence suggests antibiotic prophylaxis is unnecessary, many surgeons still advocate for its routine use. This study surveys prescription patterns of Department of Defense (DoD) general surgeons.

METHODS

An anonymous survey was sent electronically to approximately 350 DoD general surgeons. The survey asked multiple-choice and free text answers about prescribing patterns and knowledge of current evidence for low-risk patients undergoing elective open inguinal hernia repair without mesh (OIHRWOM), open inguinal hernia repair with mesh (OIHRWM), or laparoscopic inguinal hernia repair (LIHR).

RESULTS

110 DoD general surgeons consented to participate. 58.6, 95 and 84.2% of surgeons always administer antibiotic prophylaxis in OIHRWOM, OIHRWM, and LIHR, respectively. 37.9, 70.9, and 63.2% of surgeons believe that it reduces rates of surgical site infection in OIHRWOM, OIHRWM, and LIHR, respectively. The most common reasons for empirically prescribing antibiotic prophylaxis include "I think the evidence supports it" (27 of 72 responses), "I would rather be conservative and safe" (15 of 72 responses), and "I am following my hospital/department guidelines" (9 of 72 responses). 11.8, 40.8, and 32.9% of surgeons believe current evidence supports antibiotic prophylaxis use in OIHRWM, OIHRWOM, and LIHR, respectively. 50, 18.4, and 22.4% of surgeons believe current evidence refutes antibiotic prophylaxis use in OIHRWM, OIHRWOM, and LIHR, respectively.

CONCLUSION

The survey results indicate that the majority of practicing DoD general surgeons still empirically prescribe surgical antibiotic prophylaxis in IHR despite more conflicting opinions that it has no meaningful effect or that current evidence does not supports its use.

Predicting visual success in macular hole surgery

AIM

Data on the outcome of surgery facilitate informed preoperative patient counselling. Most studies on the outcome of surgery for idiopathic full thickness macular hole surgery have concentrated on rates of anatomical closure. The aim of this study was to identify factors predicting visual success (better than 20/40; 6/12 Snellen) following macular hole surgery.

METHODS

A retrospective study of 133 patients undergoing standardised macular hole surgery with at least 3 months of postoperative follow-up. All patients underwent preoperative measurement of the maximum macular hole diameter using optical coherence tomography.

RESULTS

Multivariable regression analysis identified that age, preoperative visual acuity and macular hole size were significant predictors of visual success. The resulting model correctly classified the visual outcome of 80% of cases. Predicted rates of visual success varied from 93% in patients <60 years old with visual acuity better than 6/24 and a hole diameter of <350 mum, to 2% in patients those >79 years old with visual acuity of 6/60 or worse and hole diameter of >500 microm.

CONCLUSION

The results provide a simple and clinically useful model to employ when counselling patients on macular hole surgery.

Clinical and pathologic overlap in nonsteroidal anti-inflammatory drug-related small bowel diaphragm disease and the neuromuscular and vascular hamartoma of the small bowel

Diaphragm disease (DD) is a radiographically subtle cause of small bowel obstruction and is part of the spectrum of diseases associated with nonsteroidal anti-inflammatory drug injury. The neuromuscular and vascular hamartoma (NMVH) is a nonepithelial hamartomatous, submucosally based proliferation of mature submucosal elements capable of causing small bowel obstruction. The authors report two patients in whom the clinical setting and gross pathology are that of DD, but the histologic characterization is identical to that described for NMVH. It is probable that in some patients the two diseases overlap so that some patients readily fit the criteria for both entities.

The role of anticoagulation in pylephlebitis

BACKGROUND

Pylephlebitis may complicate any intra-abdominal infection and carries a high mortality rate. Acute cases are usually anticoagulated to prevent thrombus extension and enteric ischemia; however, the role of anticoagulation has not been clearly defined.

METHODS

Over a 3-year period, pylephlebitis was diagnosed in 44 patients with portal vein thrombosis on computed tomography scan with fever, leukocytosis, and/or positive blood cultures. The charts were reviewed for etiology, extent of venous thrombosis, and method and results of treatment.

RESULTS

Eighteen patients were hypercoagulable, due to clotting factor deficiencies (6), malignancy (8), or AIDS (4). Fifteen patients had mesenteric vein involvement. Thirty-two patients were not anticoagulated, and 5 died (3 with hypercoagulable states and 2 with normal clotting function). Twelve patients were anticoagulated, and none developed subsequent bowel infarction or died.

CONCLUSION

Patients with pylephlebitis and a hypercoagulable state due to neoplasms or clotting factor deficiencies should be anticoagulated. Patients with normal clotting function and mesenteric vein involvement may also benefit. We believe anticoagulation in patients with thrombus isolated to the portal vein and normal clotting function may be unnecessary.

Ventilator pattern influences neutrophil influx and activation in atelectasis-prone rabbit lung

Both ventilator pattern and neutrophil activation influence lung injury in adult respiratory distress syndrome (ARDS). We therefore questioned whether ventilator pattern independently affects neutrophil accumulation and function in early ARDS. Thirty-five New Zealand White rabbits were anesthetized, paralyzed, and prepared using sterile techniques. Fifteen surfactant-depleted animals were randomized and ventilated for 4 h using high-frequency oscillatory ventilation (HFO) at 15 Hz with an inspired O2 fraction = 1.0 and arterial PO2 (PaO2) > 400 Torr (a pattern known to reverse atelectasis) or conventional mechanical ventilation (CMV) with PaO2 = 80-100 Torr (a pattern with some atelectasis despite positive end-expiratory pressure). Eight normal animals on CMV with PaO2 > 400 Torr served as a reference group (NorCMV). NorCMV animals progressively increased circulating polymorphonuclear neutrophil (PMN) numbers and had minor pressure-volume curve alterations but no other significant changes. Lavaged CMV animals developed the characteristic gas exchange and marked pressure-volume curve abnormalities of ARDS. Circulating PMNs remained constant but developed decreased chemotactic activity, whereas lung neutrophil numbers increased significantly (P = 0.0002) and had substantially enhanced chemiluminescence (P = 0.0003 vs. NorCMV animals). Although lavaged HFO animals accumulated an intermediate number of lung neutrophils (lung myeloperoxidase > NorCMV animals; P = 0.003), the chemiluminescence and chemotaxis of these PMNs were the same as in cells from NorCMV animals. We concluded that both the degree of neutrophil activation and lung injury can be minimized by preventing cyclic alveolar/airway expansion and collapse in the surfactant-deficient lung by use of appropriate ventilator patterns.