Glucocorticoid use in acute respiratory failure from pulmonary causes and association with early changes in the systemic host immune response

BACKGROUND

Glucocorticoids are commonly used in patients with or at-risk for acute respiratory distress syndrome (ARDS), but optimal use remains unclear despite well-conducted clinical trials. We performed a secondary analysis in patients previously enrolled in the Acute Lung Injury and Biospecimen Repository at the University of Pittsburgh. The primary aim of our study was to investigate early changes in host response biomarkers in response to real-world use of glucocorticoids in patients with acute respiratory failure due to ARDS or at-risk due to a pulmonary insult. Participants had baseline plasma samples obtained on study enrollment and on follow-up 3 to 5 days later to measure markers of innate immunity (IL-6, IL-8, IL-10, TNFr1, ST2, fractalkine), epithelial injury (sRAGE), endothelial injury (angiopoietin-2), and host response to bacterial infections (procalcitonin, pentraxin-3). In our primary analyses, we investigated the effect of receiving glucocorticoids between baseline and follow-up samples on host response biomarkers measured at follow-up by doubly robust inverse probability weighting analysis. In exploratory analyses, we examined associations between glucocorticoid use and previously characterized host response subphenotypes (hyperinflammatory and hypoinflammatory).

RESULTS

67 of 148 participants (45%) received glucocorticoids between baseline and follow-up samples. Dose and type of glucocorticoids varied. Regimens that used hydrocortisone alone were most common (37%), and median daily dose was equivalent to 40 mg methylprednisolone (interquartile range: 21, 67). Participants who received glucocorticoids were more likely to be female, to be on immunosuppressive therapy at baseline, and to have higher baseline levels of ST-2, fractalkine, IL-10, pentraxin-3, sRAGE, and TNFr1. Glucocorticoid use was associated with decreases in IL-6 and increases in fractalkine. In exploratory analyses, glucocorticoid use was more frequent in participants in the hyperinflammatory subphenotype (58% vs 40%, p = 0.05), and was not associated with subphenotype classification at the follow-up time point (p = 0.16).

CONCLUSIONS

Glucocorticoid use varied in a cohort of patients with or at-risk for ARDS and was associated with early changes in the systemic host immune response.

Feasibility of a Composite Measure of Pulmonary Vascular Impedance and Application to Patients with Chronic RV Failure Post LVAD Implant

Pulmonary vascular impedance (PVZ) describes RV afterload in the frequency domain and has not been studied extensively in LVAD patients. We sought to determine (1) feasibility of calculating a composite (c)PVZ using standard of care (SoC), asynchronous, pulmonary artery pressure (PAP) and flow (PAQ) waveforms; and (2) if chronic right ventricular failure (RVF) post-LVAD implant was associated with changes in perioperative cPVZ.PAP and PAQ were obtained via SoC procedures at three landmarks: T(1), Retrospectively, pre-operative with patient conscious; and T(2) and T(3), prospectively with patient anesthetized, and either pre-sternotomy or chest open with LVAD, respectively. Additional PAP's were taken at T(4), following chest closure; and T(5), 4-24 h post chest closure. Harmonics (z) were calculated by Fast Fourier Transform (FFT) with cPVZ(z) = FFT(PAP)/FFT(PAQ). Total pulmonary resistance Z(0); characteristic impedance Zc, mean of cPVZ(2-4); and vascular stiffness PVS, sum of cPVZ(1,2), were compared at T(1,2,3) between +/-RVF groups.Out of 51 patients, nine experienced RVF. Standard hemodynamics and changes in cPVZ-derived parameters were not significant between groups at any T.In conclusion, cPVZ calculated from SoC measures is possible. Although data that could be obtained were limited it suggests no difference in RV afterload for RVF patients post-implant. If confirmed in larger studies, focus should be placed on cardiac function in these subjects.

Trajectories of Host-Response Subphenotypes in Patients With COVID-19 Across the Spectrum of Respiratory Support

BACKGROUND

Hospitalized patients with severe COVID-19 follow heterogeneous clinical trajectories, requiring different levels of respiratory support and experiencing diverse clinical outcomes. Differences in host immune responses to SARS-CoV-2 infection may account for the heterogeneous clinical course, but we have limited data on the dynamic evolution of systemic biomarkers and related subphenotypes. Improved understanding of the dynamic transitions of host subphenotypes in COVID-19 may allow for improved patient selection for targeted therapies.

RESEARCH QUESTION

We examined the trajectories of host-response profiles in severe COVID-19 and evaluated their prognostic impact on clinical outcomes.

STUDY DESIGN AND METHODS

In this prospective observational study, we enrolled 323 inpatients with COVID-19 receiving different levels of baseline respiratory support: (1) low-flow oxygen (37%), (2) noninvasive ventilation (NIV) or high-flow oxygen (HFO; 29%), (3) invasive mechanical ventilation (27%), and (4) extracorporeal membrane oxygenation (7%). We collected plasma samples on enrollment and at days 5 and 10 to measure host-response biomarkers. We classified patients by inflammatory subphenotypes using two validated predictive models. We examined clinical, biomarker, and subphenotype trajectories and outcomes during hospitalization.

RESULTS

IL-6, procalcitonin, and angiopoietin 2 persistently were elevated in patients receiving higher levels of respiratory support, whereas soluble receptor of advanced glycation end products (sRAGE) levels displayed the inverse pattern. Patients receiving NIV or HFO at baseline showed the most dynamic clinical trajectory, with 24% eventually requiring intubation and exhibiting worse 60-day mortality than patients receiving invasive mechanical ventilation at baseline (67% vs 35%; P < .0001). sRAGE levels predicted NIV failure and worse 60-day mortality for patients receiving NIV or HFO, whereas IL-6 levels were predictive in all patients regardless of level of support (P < .01). Patients classified to a hyperinflammatory subphenotype at baseline (< 10%) showed worse 60-day survival (P < .0001) and 50% of them remained classified as hyperinflammatory at 5 days after enrollment.

INTERPRETATION

Longitudinal study of the systemic host response in COVID-19 revealed substantial and predictive interindividual variability influenced by baseline levels of respiratory support.

Longitudinal Analysis of Caregiver Burden in Head and Neck Cancer

Importance

Despite the critical role of caregivers in head and neck cancer (HNC), there is limited literature on caregiver burden (CGB) and its evolution over treatment. Research is needed to address evidence gaps that exist in understanding the causal pathways between caregiving and treatment outcomes.

Objective

To evaluate the prevalence of and identify risk factors for CGB in HNC survivorship.

Design, Setting, and Participants

This longitudinal prospective cohort study took place at the University of Pittsburgh Medical Center. Dyads of treatment-naive patients with HNC and their caregivers were recruited between October 2019 and December 2020. Eligible patient-caregiver dyads were 18 years or older and fluent in English. Patients undergoing definitive treatment identified a caregiver as the primary, nonprofessional, nonpaid person who provided the most assistance to them. Among 100 eligible dyadic participants, 2 caregivers declined participation, resulting in 96 enrolled participants. Data were analyzed from September 2021 through October 2022.

Main Outcomes and Measures

Participants were surveyed at diagnosis, 3 months postdiagnosis, and 6 months postdiagnosis. Caregiver burden was evaluated with the 19-item Social Support Survey (scored 0-100, with higher scores indicating more support), Caregiver Reaction Assessment (CRA; scored 0-5, with higher scores on 4 subscales [disrupted schedule, financial problems, lack of family support, and health problems] indicating negative reactions, and higher scores on the fifth subscale [self-esteem] indicating favorable influence); and 3-item Loneliness Scale (scored 3-9, with higher scores indicating greater loneliness). Patient health-related quality of life was assessed using the University of Washington Quality of Life scale (UW-QOL; scored 0-100, with higher scores indicating better QOL).

Results

Of the 96 enrolled participants, half were women (48 [50%]), and a majority were White (92 [96%]), married or living with a partner (81 [84%]), and working (51 [53%]). Of these participants, 60 (63%) completed surveys at diagnosis and at least 1 follow-up. Of the 30 caregivers, most were women (24 [80%]), White (29 [97%]), married or living with a partner (28 [93%]), and working (22 [73%]). Caregivers of nonworking patients reported higher scores on the CRA subscale for health problems than caregivers of working patients (mean difference, 0.41; 95% CI, 0.18-0.64). Caregivers of patients with UW-QOL social/emotional (S/E) subscale scores of 62 or lower at diagnosis reported increased scores on the CRA subscale for health problems (UW-QOL-S/E score of 22: CRA score mean difference, 1.12; 95% CI, 0.48-1.77; UW-QOL-S/E score of 42: CRA score mean difference, 0.74; 95% CI, 0.34-1.15; and UW-QOL-S/E score of 62: CRA score mean difference, 0.36; 95% CI, 0.14-0.59). Woman caregivers had statistically significant worsening scores on the Social Support Survey (mean difference, -9.18; 95% CI, -17.14 to -1.22). The proportion of lonely caregivers increased over treatment.

Conclusions and Relevance

This cohort study highlights patient- and caregiver-specific factors that are associated with increased CGB. Results further demonstrate the potential implications for negative health outcomes for caregivers of patients who are not working and have lower health-related quality of life.

Heart-Brain 346-7 Score: the development and validation of a simple mortality prediction score for carbon monoxide poisoning utilizing deep learning

INTRODUCTION

Acute mortality from carbon monoxide poisoning is 1-3%. The long-term mortality risk of survivors of carbon monoxide poisoning is doubled compared to age-matched controls. Cardiac involvement also increases mortality risk. We built a clinical risk score to identify carbon monoxide-poisoned patients at risk for acute and long-term mortality.

METHODS

We performed a retrospective analysis. We identified 811 adult carbon monoxide-poisoned patients in the derivation cohort, and 462 adult patients in the validation cohort. We utilized baseline demographics, laboratory values, hospital charge transactions, discharge disposition, and clinical charting information in the electronic medical record in Stepwise Akaike's Information Criteria with Firth logistic regression to determine optimal parameters to create a prediction model.

RESULTS

In the derivation cohort, 5% had inpatient or 1-year mortality. Three variables following the final Firth logistic regression minimized Stepwise Akaike's Information Criteria: altered mental status, age, and cardiac complications. The following predict inpatient or 1-year mortality: age > 67, age > 37 with cardiac complications, age > 47 with altered mental status, or any age with cardiac complications and altered mental status. The sensitivity of the score was 82% (95% confidence interval: 65-92%), the specificity was 80% (95% confidence interval: 77-83%), negative predictive value was 99% (95% confidence interval: 98-100%), positive predictive value 17% (95% confidence interval: 12-23%), and the area under the receiver operating characteristic curve was 0.81 (95% confidence interval: 0.74-0.87). A score above the cut-off point of -2.9 was associated with an odds ratio of 18 (95% confidence interval: 8-40). In the validation cohort (462 patients), 4% had inpatient death or 1-year mortality. The score performed similarly in the validation cohort: sensitivity was 72% (95% confidence interval: 47-90%), specificity was 69% (95% confidence interval: 63-73%), negative predictive value was 98% (95% confidence interval: 96-99%), positive predictive value was 9% (95% confidence interval: 5-15%) and the area under the receiver operating characteristic curve was 0.70 (95% confidence interval: 60%-81%).

CONCLUSIONS

We developed and validated a simple, clinical-based scoring system, the Heart-Brain 346-7 Score to predict inpatient and long-term mortality based on the following: age > 67, age > 37 with cardiac complications, age > 47 with altered mental status, or any age with cardiac complications and altered mental status. With further validation, this score will hopefully aid decision-making to identify carbon monoxide-poisoned patients with higher mortality risk.

A Model to Predict Residual Volume from Forced Spirometry Measurements in Chronic Obstructive Pulmonary Disease

Background

Lung hyperinflation with elevated residual volume (RV) is associated with poor prognosis in adults with chronic obstructive pulmonary disease (COPD) and is a critical criterion for lung volume reduction selection. Here, we proposed that patterns within spirometric measures could represent the degree of hyperinflation.

Methods

Fractional polynomial multivariate regression was used to develop a prediction model based on age, biological sex, forced expiratory volume in 1 second (FEV₁), and forced vital capacity (FVC) to estimate plethysmography measured RV in patients in the Pittsburgh Specialized Center for Clinically Oriented Research (SCCOR) cohort (n=450). Receiver operating characteristic area under the curve (ROC-AUC) and optimal cut-points from the model were identified. The model was validated in a separate cohort (n=793).

Results

The best fit model: RV %est=[FVC %predicted] x 3.46-[FEV₁/FVC] x 179.80- [FVC % (sqrt)] x 79.53-[age] x 0.98- [sex] x 10.88 + 737.06, where [sex], m=1. R² of observed versus %predicted RV was 0.71. The optimal cut-point to predict an RV % >175% was 161. At this cut-point, ROC-AUC was 0.95, with a sensitivity 0.95, specificity 0.86, positive predictive value (PPV) of 97%, negative predictive value (NPV) of 76%, positive likelihood ratio (LR) of 6.6, and negative LR of 0.06. In a validation cohort of COPD patients (n=793), the model performed similarly, with a sensitivity of 0.82, specificity of 0.83, PPV of 85%, NPV of 79%, positive LR of 4.7, and negative LR of 0.21.

Conclusion

In patients with COPD, a model using only spirometry, age, and biological sex can estimate elevated RV. This tool could facilitate the identification of candidates for lung volume reduction procedures and can be integrated into existing epidemiologic databases to investigate the clinical impact of hyperinflation.

Resuscitation with epinephrine worsens cerebral capillary no-reflow after experimental pediatric cardiac arrest: An in vivo multiphoton microscopy evaluation

Epinephrine is the principal resuscitation therapy for pediatric cardiac arrest (CA). Clinical data suggest that although epinephrine increases the rate of resuscitation, it fails to improve neurological outcome, possibly secondary to reductions in microvascular flow. We characterized the effect of epinephrine vs. placebo administered at resuscitation from pediatric asphyxial CA on microvascular and macrovascular cortical perfusion assessed using in vivo multiphoton microscopy and laser speckle flowmetry, respectively, and on brain tissue oxygenation (PbO₂), behavioral outcomes, and neuropathology in 16-18-day-old rats. Epinephrine-treated rats had a more rapid return of spontaneous circulation and brisk immediate cortical reperfusion during 1-3 min post-CA vs. placebo. However, at the microvascular level, epinephrine-treated rats had penetrating arteriole constriction and increases in both capillary stalling (no-reflow) and cortical capillary transit time 30-60 min post-CA vs. placebo. Placebo-treated rats had increased capillary diameters post-CA. The cortex was hypoxic post-CA in both groups. Epinephrine treatment worsened reference memory performance vs. shams. Hippocampal neuron counts did not differ between groups. Resuscitation with epinephrine enhanced immediate reperfusion but produced microvascular alterations during the first hour post-resuscitation, characterized by vasoconstriction, capillary stasis, prolonged cortical transit time, and absence of compensatory cortical vasodilation. Targeted therapies mitigating the deleterious microvascular effects of epinephrine are needed.

Trajectories of host-response biomarkers and inflammatory subphenotypes in COVID-19 patients across the spectrum of respiratory support

Purpose

Enhanced understanding of the dynamic changes in the dysregulated inflammatory response in COVID-19 may help improve patient selection and timing for immunomodulatory therapies.

Methods

We enrolled 323 COVID-19 inpatients on different levels of baseline respiratory support: i) Low Flow Oxygen (37%), ii) Non-Invasive Ventilation or High Flow Oxygen (NIV_HFO, 29%), iii) Invasive Mechanical Ventilation (IMV, 27%), and iv) Extracorporeal Membrane Oxygenation (ECMO, 7%). We collected plasma samples upon enrollment and days 5 and 10 to measure host-response biomarkers. We classified subjects into inflammatory subphenotypes using two validated predictive models. We examined clinical, biomarker and subphenotype trajectories and outcomes during hospitalization.

Results

IL-6, procalcitonin, and Angiopoietin-2 were persistently elevated in patients at higher levels of respiratory support, whereas sRAGE displayed the inverse pattern. Patients on NIV_HFO at baseline had the most dynamic clinical trajectory, with 26% eventually requiring intubation and exhibiting worse 60-day mortality than IMV patients at baseline (67% vs. 35%, p<0.0001). sRAGE levels predicted NIV failure and worse 60-day mortality for NIV_HFO patients, whereas IL-6 levels were predictive in IMV or ECMO patients. Hyper-inflammatory subjects at baseline (<10% by both models) had worse 60-day survival (p<0.0001) and 50% of them remained classified as hyper-inflammatory on follow-up sampling at 5 days post-enrollment. Receipt of combined immunomodulatory therapies (steroids and anti-IL6 agents) was associated with markedly increased IL-6 and lower Angiopoietin-2 levels (p<0.05).

Conclusions

Longitudinal study of systemic host responses in COVID-19 revealed substantial and predictive inter-individual variability, influenced by baseline levels of respiratory support and concurrent immunomodulatory therapies.

Fractional Exhaled Nitric Oxide as a Marker of Mucosal Inflammation in Chronic Rhinosinusitis

BACKGROUND

Fractional exhaled nitric oxide (FeNO) is a cost-effective, noninvasive point-of-care test that has proven valuable in identifying patients with lower airway inflammation and predicting the likelihood of responsiveness to inhaled corticosteroid therapy in asthma. The utility of FeNO in upper airway disease, specifically in CRS, remains to be determined.

OBJECTIVE

The goal of this study was to test whether FeNO could serve as a noninvasive marker of sinonasal mucosal inflammation in CRS patients.

METHODS

FeNO was obtained using a nitric oxide analyzer (NIOX VERO) as well as nasal mucus, the 22-item Sinonasal Outcome Test (SNOT-22), University of Pennsylvania Smell Identification Test (UPSIT), and Lund-Kennedy endoscopic scores concurrently in 112 CRS patients. Nasal mucus was analyzed for cytokine expression using solid-phase sandwich ELISA. Linear regression with Spearman correlation coefficient was used to determine strength of relationship between variables.

RESULTS

CRS patients showed elevated FeNO levels with asthma (47.12 ± 5.21 ppb) or without asthma (43.24 ± 9.810 ppb). Elevated FeNO levels correlated with sinonasal mucosal inflammation, as determined by increased levels of CCL26 and TNFα in nasal mucus obtained from CRS patients. Furthermore, elevated FeNO levels selectively correlated with worsened SNOT-22 nasal symptoms (P = 0.03) and Lund-Kennedy endoscopic scores (P = 0.007), but did not correlate with UPSIT scores.

CONCLUSIONS

FeNO levels correlated with increased sinonasal mucosal inflammation and symptom severity in CRS regardless of asthma status. FeNO measurements may serve as a quick and noninvasive marker in evaluating CRS patients.

Association of Systemic Inflammation with Depressive Symptoms in Individuals with COPD

Rationale

Depression is a prevalent comorbidity of chronic obstructive pulmonary disease (COPD) that, along with COPD, has been associated with inflammation. An association between inflammation and depression in COPD has not been validated in a large COPD cohort.

Methods

Individuals from the University of Pittsburgh SCCOR cohort and the COPDGene cohort with tobacco use history and airway obstruction (FEV₁/FVC <0.7) were evaluated using the Beck Depression Inventory II (BDI-II) and the Hospital Anxiety and Depression Scale (HADS), respectively. Participants completed symptom-related questionnaires and plasma IL-6 measurements. T-test, Fisher’s Exact tests and logistic regression were used for statistical analysis.

Results

The SCCOR cohort included 220 obstructed participants: 44% female and 21.4% with elevated depressive symptoms. GOLD staging distribution was predominantly stage I and II. The COPDGene cohort included 745 obstructed participants: 44% female and 13.0% with elevated depressive symptoms. GOLD distribution was predominantly stage II and III. In the SCCOR cohort, correlation between IL-6 and depressive symptoms trended toward significance (p= 0.08). Multivariable modeling adjusted for FEV₁, age, gender and medical comorbidities showed a significant association (OR = 1.70, 95% CI = 1.08–2.69). IL-6 was significantly associated with elevated depressive symptoms in COPDGene in both univariate (p=0.001) and multivariable modeling (OR = 1.52, 95% CI =1.13–2.04).

Conclusion

Elevated plasma IL-6 levels are associated with depressive symptoms in individuals with COPD independent of airflow limitation and comorbid risk factors for depression. Our results suggest that systemic inflammation may play a significant and possibly bidirectional role in depression associated with COPD.

Loss-of-function genomic variants highlight potential therapeutic targets for cardiovascular disease

Pharmaceutical drugs targeting dyslipidemia and cardiovascular disease (CVD) may increase the risk of fatty liver disease and other metabolic disorders. To identify potential novel CVD drug targets without these adverse effects, we perform genome-wide analyses of participants in the HUNT Study in Norway (n = 69,479) to search for protein-altering variants with beneficial impact on quantitative blood traits related to cardiovascular disease, but without detrimental impact on liver function. We identify 76 (11 previously unreported) presumed causal protein-altering variants associated with one or more CVD- or liver-related blood traits. Nine of the variants are predicted to result in loss-of-function of the protein. This includes ZNF529:p.K405X, which is associated with decreased low-density-lipoprotein (LDL) cholesterol (P = 1.3 × 10-8) without being associated with liver enzymes or non-fasting blood glucose. Silencing of ZNF529 in human hepatoma cells results in upregulation of LDL receptor and increased LDL uptake in the cells. This suggests that inhibition of ZNF529 or its gene product should be prioritized as a novel candidate drug target for treating dyslipidemia and associated CVD.

0357 CPAP Adherence is Lower in Minority Neighborhoods

Introduction

The effectiveness of continuous positive airway pressure (CPAP) in treating obstructive sleep apnea (OSA) is limited by adherence. Small, single-center studies have reported CPAP adherence is lower in racial minorities suggesting disparities in OSA care. We used nationally representative data to assess racial differences in CPAP adherence at a neighborhood level.

Methods

Telemonitoring data were obtained from a therapy database maintained by a CPAP manufacturer. Usage over the first 90 days in patients initiated on CPAP between 11/01/2015 and 10/31/2018 who had at least one usage session, age 18-90 years, and valid U.S. zip code were mapped to a zip code tabulation area (ZCTA). Age- and sex-adjusted CPAP usage was calculated for each ZCTA with greater than 10 CPAP users. Ecologic analyses were performed to model the association of the proportion of blacks and Hispanics in each ZCTA (obtained from the 2013-2017 American Community Survey) on CPAP usage controlling for proportion of adults with bachelor’s degree and proportion of adults with household income below the poverty line.

Results

Our analysis included 13,118 ZCTAs averaging data over 737,274 patients. In adjusted analyses, each 10% increase in the proportion of blacks and Hispanics was associated with a 0.12 (95% CI 0.11-0.12) hour and 0.14 (95% CI 0.14-0.15) hour decrease in nightly CPAP use, respectively. Mean usage in ZCTAs with &lt;1%, 1-2.5%, 2.5-10%, 10-25%, and 25-100% blacks were 4.96, 4.81, 4.67, 4.56, and 4.14 hours respectively (p&lt;0.001). Mean usage in ZCTAs with &lt;1%, 1-2.5%, 2.5-10%, 10-25%, and 25-100% Hispanics were 4.87, 4.86, 4.75, 4.50, and 4.10 hours respectively (p&lt;0.001).

Conclusion

CPAP adherence is lower in neighborhoods with higher proportions of black and Hispanic residents independent of differences in education or poverty. These differences lead to lower likelihood of meeting insurance coverage requirements for CPAP therapy, potentially exacerbating sleep health disparities.

Support

Philips Respironics, NIH R25HL130600 and K24HL127307.

Mesenchymal stem cells reduce ER stress via PERK-Nrf2 pathway in an aged mouse model

BACKGROUND AND OBJECTIVE

Mesenchymal stem cells (MSC) have been shown to ameliorate the deleterious effects of bleomycin in murine models. However, the mechanism responsible for protection from pulmonary fibrosis by stem cell therapy is still poorly understood, especially in terms of endoplasmic reticulum (ER) stress. We hypothesized that during bleomycin-induced lung injury, markers of ER stress, specifically the activation of the unfolded protein response (UPR), increase during injury, resembling the kinetics of collagen deposition in the lung described for the bleomycin model. We aimed to elucidate the possible role of MSC in ER stress modulation.

METHODS

To determine the kinetics of ER stress in aged mice, the expression of ER stress markers after bleomycin lung injury was measured in old mice at different time points (days 0, 3, 7, 14 and 21). To evaluate the consequences of systemic delivery of MSC on lung ER stress in the bleomycin model, we evaluated changes in body weight, lung histology and protein expression of ER stress markers.

RESULTS

The level of expression of UPR transcription factor XBP-1 and its regulator BiP was elevated at day 7 and progressively increased up to day 21. MSC inhibited BiP expression in bleomycin-induced ER stress, attenuating ER stress via the protein kinase RNA-like ER kinase (PERK)-Nrf2 pathway. The expression levels of other ER stress markers were not perturbed by MSC.

CONCLUSION

Our data suggest that MSC operate on ER stress via several pathways, but the PERK-Nrf2 pathway revealed to be the main functioning pathway in our bleomycin model.

Abstract 1638: Is short interval colonoscopy at the discretion of the gastroenterologist

BACKGROUND: Gastroenterologists do not always follow guidelines for performing colonoscopies. Short interval colonoscopies are recommended at the discretion of gastroenterologists depending on various factors. We here evaluated such factors in an African American patient population.

AIM: To assess factors contributing to short interval (within 3 months) colonoscopies.

METHODS: Data was retrieved retrospectively from Howard University Hospital database (Jan. 2010 to Dec. 2016). African American patients who had repeated colonoscopies within a period of 3 months were selected for this study. We analyzed patients' demographics, family history, polyp characteristics, and reasons for repeat colonoscopy along with latest follow-up findings.

RESULTS: There were 36 patients who underwent two colonoscopies within 3 months, 13 females and 23 males with mean age of 61 years. Out of these, 7 patients (19.4%) had poor bowel preparation. For the remaining 29 patients, the reason for second colonoscopy were partial removal and suspicion of partial removal (61.1%), difficult access (16.7%), and follow-up for Crohn's disease (2.8%). Follow-up of these 36 patients after their last colonoscopy revealed that 8 patients (22.2%) had colon cancer/resection, 4 other patients (11.1%) had cancer of other organs. Of the remaining, 6 (16.6%) had future colon polyp resection, 3 (8.3%) had normal screening colonoscopy and 4 (11.1%) visited the hospital for reasons unrelated to gastroenterology while 11 patients (30.6%) had no follow up.

CONCLUSION: Even though there are no recommendations to repeat colonoscopy within 3 months, endoscopists perform such colonoscopies at their own discretion based on factors like high risk individuals, poor bowel preparation, multiple lesions, type of lesions and resection clearance. Of interest, a significant number of patients in our study had colon cancer/resection on eventual follow-ups.

Citation Format: Hassan Brim, Abhimanyu Tushir, Shashidhar Manchegowda, Negin Farsi, Edward L. Lee, Laiyemo O. Adeyinka, Seyed M. Nouraie, Hassan Ashktorab. Is short interval colonoscopy at the discretion of the gastroenterologist [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1638.

Abstract 5056: HPV, HIV and male gender as major risk factors for anal neoplastic transformation in African Americans

Background: Human Papilloma Virus (HPV) is the most common sexually transmitted infectious agent. The incidence HPV-related anal cancers increased among HIV infected people. Aim: To assess risk factors of anal lesions among African Americans in an inner city hospital. Methods: We reviewed medical records of 370 African-Americans with anal lesions at Howard University Hospital from Jan. 2007 to Dec. 2015. Demographic, clinical and pathological data including; HPV, HIV, HCV (hepatitis C virus), diabetes mellitus (DM), hypertension (HTN) and body mass index (BMI) were collected. Statistical analysis was performed using Chi-square and Student's t-test. Results: 276 (75%) patients were male, with median age of 44 years and BMI of 25.8 kg/m2. The frequency of condyloma, high grade dysplasia, squamous cell carcinoma (SCC) and adenocarcinoma was 191 (52%), 26 (7%), 31 (8%) and 8 (2%), respectively. The frequency of HPV, HIV, and HCV was 231 (68%), 147 (43%) and 42 (12%), respectively. HPV and HIV were risk factors for condyloma and dysplasia (P&lt;0.05). Forty two percent of patients had diabetes (DM) and hypertension (HTN). Conclusion: Our results shows that majority of patients with condyloma are male and young with HPV and HIV infection. A clinical utility of HPV as risk factor may be use for prediction of anal lesions.

Citation Format: Hassan Brim, Ali Afsari, Nazli Atefi, Nicole Retland, Muneer Abbas, Tammey Naab, Babak Shokrani, Adeyinka O. Laiyemo, Edward L. Lee, Seyed M. Nouraie, Hassan Ashktorab. HPV, HIV and male gender as major risk factors for anal neoplastic transformation in African Americans [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5056.

The matricellular protein TSP1 promotes human and mouse endothelial cell senescence through CD47 and Nox1

Senescent cells withdraw from the cell cycle and do not proliferate. The prevalence of senescent compared to normally functioning parenchymal cells increases with age, impairing tissue and organ homeostasis. A contentious principle governing this process has been the redox theory of aging. We linked matricellular protein thrombospondin 1 (TSP1) and its receptor CD47 to the activation of NADPH oxidase 1 (Nox1), but not of the other closely related Nox isoforms, and associated oxidative stress, and to senescence in human cells and aged tissue. In human endothelial cells, TSP1 promoted senescence and attenuated cell cycle progression and proliferation. At the molecular level, TSP1 increased Nox1-dependent generation of reactive oxygen species (ROS), leading to the increased abundance of the transcription factor p53. p53 mediated a DNA damage response that led to senescence through Rb and p21^cip, both of which inhibit cell cycle progression. Nox1 inhibition blocked the ability of TSP1 to increase p53 nuclear localization and p21^cip abundance and its ability to promote senescence. Mice lacking TSP1 showed decreases in ROS production, p21^cip expression, p53 activity, and aging-induced senescence. Conversely, lung tissue from aging humans displayed increases in the abundance of vascular TSP1, Nox1, p53, and p21^cip Finally, genetic ablation or pharmacological blockade of Nox1 in human endothelial cells attenuated TSP1-mediated ROS generation, restored cell cycle progression, and protected against senescence. Together, our results provide insights into the functional interplay between TSP1 and Nox1 in the regulation of endothelial senescence and suggest potential targets for controlling the aging process at the molecular level.

Mediastinal and Subcutaneous Chest Fat Are Differentially Associated with Emphysema Progression and Clinical Outcomes in Smokers

BACKGROUND

Studies have demonstrated both positive and negative effects of obesity on clinical outcomes in chronic obstructive pulmonary disease (COPD). In other chronic diseases, fat location is differentially associated with disease outcomes; however, this relationship has not been well studied in COPD.

OBJECTIVE

To determine if fat location explains the differential association of body mass index (BMI) with clinical outcome measures in smokers.

METHODS

Baseline and 6-year chest computed tomography scans from 68 current and former smokers were used to quantify mediastinal and subcutaneous fat. The relationships of BMI, mediastinal fat, and subcutaneous fat with cross-sectional and 6-year changes in pulmonary function, incremental shuttle walk distance (ISWD), quantitative emphysema, and circulating interleukin-6 (IL-6) and C-reactive protein (CRP) levels were assessed using generalized linear models adjusted for clinically relevant covariates.

RESULTS

Baseline subcutaneous fat was negatively associated with emphysema progression over 6 years (p < 0.01). BMI and mediastinal fat volume were inversely associated with baseline ISWD (p < 0.01 and p = 0.043, respectively) as well as 6-year change in ISWD (p = 0.020 and p = 0.028, respectively). IL-6 was directly associated with BMI and mediastinal fat (p < 0.01) and CRP was directly associated with BMI only (p = 0.033).

CONCLUSIONS

Increased subcutaneous chest fat is associated with less emphysema progression over time in smokers, while increased mediastinal fat volume is associated with decreased walk distance and increased IL-6 levels. These findings suggest a complex interaction between fat, inflammation, and emphysema that should be considered when phenotyping patients with COPD and provide new evidence of an inverse association between emphysema progression and chest subcutaneous fat.

IRF5 distinguishes severe asthma in humans and drives Th1 phenotype and airway hyperreactivity in mice

Severe asthma (SA) is a significant problem both clinically and economically, given its poor response to corticosteroids (CS). We recently reported a complex type 1-dominated (IFN-γ-dominated) immune response in more than 50% of severe asthmatics despite high-dose CS treatment. Also, IFN-γ was found to be critical for increased airway hyperreactivity (AHR) in our model of SA. The transcription factor IRF5 expressed in M1 macrophages can induce a Th1/Th17 response in cocultured human T cells. Here we show markedly higher expression of IRF5 in bronchoalveolar lavage (BAL) cells of severe asthmatics as compared with that in cells from milder asthmatics or healthy controls. Using our SA mouse model, we demonstrate that lack of IRF5 in lymph node migratory DCs severely limits their ability to stimulate the generation of IFN-γ- and IL-17-producing CD4+ T cells and IRF5-/- mice subjected to the SA model displayed significantly lower IFN-γ and IL-17 responses, albeit showing a reciprocal increase in Th2 response. However, the absence of IRF5 rendered the mice responsive to CS with suppression of the heightened Th2 response. These data support the notion that IRF5 inhibition in combination with CS may be a viable approach to manage disease in a subset of severe asthmatics.