A78 “CHALLENGING PERSPECTIVES:” UNDERSTANDING CLINICIANS VIEWS ON MANAGING ALCOHOL USE DISORDER AND CIRRHOSIS

Background

Alcohol use disorder (AUD) is one of the leading etiologies for liver cirrhosis and liver transplantation. Few individuals with AUD receive guideline-based care in the form of screening, brief intervention, referral to treatment, or prescription of anti-relapse pharmacotherapies. We interviewed clinicians across Alberta to assess the current experience and perceived barriers to managing AUD in people who have cirrhosis.

Aims

The aim of this project is to summarize these findings to inform the development of an educational intervention.

Methods

We used a qualitative descriptive approach to explore the experiences of clinicians who provide care for patients with cirrhosis and AUD in Alberta. We conducted semi-structured interviews directed by an interview guide. Interviews were recorded and transcribed verbatim. We used an inductive thematic analysis approach whereby transcripts were coded, with codes grouped into larger categories, then themes.

Results

Sixteen clinicians participated in this study. Many participants acknowledged that they do not use a standardized approach to screening, brief intervention, and referral to treatment. Through thematic analysis we identified three themes surrounding barriers to managing AUD in patients with cirrhosis: (i) Practicing within knowledge constraints, (ii) Navigating limited resources and system challenges, and (iii) Acknowledging the complexity of patients who have cirrhosis and AUD.

Conclusions

This research presents the perspectives of clinicians who manage people who have AUD and cirrhosis. Our results indicate that significant barriers exist that affect how clinicians manage AUD in the context of cirrhosis, including limited knowledge and resources, systemic challenges, and patient complexity. The information gathered in this investigation will be used to develop an accredited educational intervention that will delve deeper into these issues in order to have the greatest impact on clinicians who routinely interface with this patient population.

Funding Agencies

Alberta Innovates Health Solutions

A87 CHANGES IN CLINICIAN KNOWLEDGE, COMFORT, PREPAREDNESS, AND ATTITUDES ABOUT ALCOHOL USE DISORDER AND CIRRHOSIS AFTER A BRIEF EDUCATIONAL INTERVENTION

Background

Alcohol use disorder (AUD) is increasing in prevalence and has a substantial impact on morbidity and mortality in people with cirrhosis. The use of screening, brief intervention and referral to treatment (SBIRT) and relapse prevention medications (e.g. acamprosate) are recommended by recent guidelines. Unfortunately, many clinicians report insufficient training to feel confident using these interventions

Aims

We aimed to compare the effect of a brief educational intervention on AUD knowledge, comfort, attitudes, and preparedness in clinicians who provide care to patients with cirrhosis.

Methods

Clinicians were invited to participate in a 1.5-hour educational session conducted by a hepatologist and addiction medicine specialist. The session included information about SBIRT and pharmacotherapy. Pre-training knowledge, comfort, and practice behaviors were assessed using previously published questions. Baseline attitudes were measured using the Short Alcohol and Alcohol Problems Perception Questionnaire. Participants were invited to repeat the questionnaires immediately post-training and statistical analysis conducted.

Results

Eighty-two clinicians attended the session. Among the 38 attendees who completed both the pre- and post-questionnaires, 34% were GIs/internists, 45% were family medicine physicians, and the remainder (21%) did not specify or were not prescribers. Scores for self-reported intention and preparedness to treat AUD, comfort, and knowledge improved significantly from the pre-training phase. Attitudes also improved from the pre-training phase, with significant improvements in the SAAPPQ subscales of role adequacy (p=0.03) and motivation (p=0.04).

Conclusions

Recognizing the small sample size, a brief educational session demonstrated promising results in the promotion of knowledge, attitudes, preparedness, and comfort for clinicians managing AUD in patients with cirrhosis. Feedback from these sessions will be used to design an accredited educational series for roll-out in 2022.

Funding Agencies

Alberta Innovates Health Solutions

A novel approach for estimation of aboveground biomass of a carbon-rich mangrove site in India

Mangroves can play a crucial part in climate change mitigation policies due to their high carbon-storing capacity. However, the carbon sequestration potential of Indian mangroves generally remained unexplored to date. In this study, multi-temporal Sentinel-1 and 2 data-derived variables were used to estimate the AGB of a tropical carbon-rich mangrove forest of India. Ensemble prediction of multiple machine learning algorithms, including Random Forest (RF), Gradient Boosted Model (GBM), and Extreme Gradient Boosting (XGB), were used for AGB prediction. The multi-temporal dataset was used in two different ways to find the most suitable method of using them. The results of the analysis showed that the modeling field measured AGB with individual date data values results in estimates with root mean square errors (RMSE) ranging from 149.242 t/ha for XGB to 151.149 t/ha for the RF. Modeling AGB with the average and percentile metrics of the multi-temporal image stack improves the prediction accuracy of AGB, with RMSE ranging from 81.882 t/ha for the XGB to 74.493 t/ha for the RF. The AGB modeling using ensemble prediction showed further improvement in accuracy with an RMSE of 72.864 t/ha and normalized RMSE of 11.38%. In this study, the intra-seasonal variation of Sentinel-1 and 2 data for mangrove ecosystems was explored for the first time. The variations in remotely sensed variables could be attributed mainly to soil moisture availability and rainfall in the mangrove ecosystem. The efficiency of Sentinel-1 and 2 data-derived variables and ensemble prediction of machine learning models for Indian mangroves were also explored for the first time. The methodologies established in this study can be used in the future for accurate prediction and repeated monitoring of AGB for mangrove ecosystems.

Dietary nitrate improves vascular function in patients with hypercholesterolemia: a randomized, double-blind, placebo-controlled study

BACKGROUND

The beneficial cardiovascular effects of vegetables may be underpinned by their high inorganic nitrate content.

OBJECTIVE

We sought to examine the effects of a 6-wk once-daily intake of dietary nitrate (nitrate-rich beetroot juice) compared with placebo intake (nitrate-depleted beetroot juice) on vascular and platelet function in untreated hypercholesterolemics.

DESIGN

A total of 69 subjects were recruited in this randomized, double-blind, placebo-controlled parallel study. The primary endpoint was the change in vascular function determined with the use of ultrasound flow-mediated dilatation (FMD).

RESULTS

Baseline characteristics were similar between the groups, with primary outcome data available for 67 patients. Dietary nitrate resulted in an absolute increase in the FMD response of 1.1% (an ∼24% improvement from baseline) with a worsening of 0.3% in the placebo group (P < 0.001). A small improvement in the aortic pulse wave velocity (i.e., a decrease of 0.22 m/s; 95% CI: -0.4, -0.3 m/s) was evident in the nitrate group, showing a trend (P = 0.06) to improvement in comparison with the placebo group. Dietary nitrate also caused a small but significant reduction (7.6%) in platelet-monocyte aggregates compared with an increase of 10.1% in the placebo group (P = 0.004), with statistically significant reductions in stimulated (ex vivo) P-selectin expression compared with the placebo group (P < 0.05) but no significant changes in unstimulated expression. No adverse effects of dietary nitrate were detected. The composition of the salivary microbiome was altered after the nitrate treatment but not after the placebo treatment (P < 0.01). The proportions of 78 bacterial taxa were different after the nitrate treatment; of those taxa present, 2 taxa were responsible for >1% of this change, with the proportions of Rothia mucilaginosa trending to increase and Neisseria flavescens (P < 0.01) increased after nitrate treatment relative to after placebo treatment.

CONCLUSIONS

Sustained dietary nitrate ingestion improves vascular function in hypercholesterolemic patients. These changes are associated with alterations in the oral microbiome and, in particular, nitrate-reducing genera. Our findings provide additional support for the assessment of the potential of dietary nitrate as a preventative strategy against atherogenesis in larger cohorts. This trial was registered at clinicaltrials.gov as NCT01493752.

"Repurposing" of Xanthine Oxidoreductase as a Nitrite Reductase: A New Paradigm for Therapeutic Targeting in Hypertension

SIGNIFICANCE

In contrast to nitric oxide (NO), which has well-established, important effects in regulation of cardiovascular homeostasis, its oxidative metabolite nitrite has, until recently, been considered to be of minor functional significance.

RECENT ADVANCES

However, this view of nitrite has been radically revised over the past 10 years with evidence now supporting a critical role for this anion as a storage form of NO.

CRITICAL ISSUES

Importantly, while hypoxia and acidosis have been shown to play a pivotal role in the generation of nitrite to NO, a number of mammalian nitrite reductases have been identified that facilitate the reduction of nitrite. Critically, these nitrite reductases have been demonstrated to operate under physiological pH conditions and in normoxia, extending the functional remit of this anion from an ischemic mediator to an important regulator of physiology. One particular nitrite reductase that has been shown to operate under a wide range of environmental conditions is the enzyme xanthine oxidoreductase (XOR).

FUTURE DIRECTIONS

In this review, we discuss the evidence supporting a role for XOR as a nitrite reductase while focusing particularly on its function in hypertension. In addition, we discuss the potential merit in exploiting this activity of XOR in the therapeutics of hypertension.

Antiplatelet effects of dietary nitrate in healthy volunteers: involvement of cGMP and influence of sex

Ingestion of vegetables rich in inorganic nitrate has emerged as an effective method, via the formation of a nitrite intermediate, for acutely elevating vascular NO levels. As such a number of beneficial effects of dietary nitrate ingestion have been demonstrated including the suggestion that platelet reactivity is reduced. In this study we investigated whether inorganic nitrate supplementation might also reduce platelet reactivity in healthy volunteers and have determined the mechanisms involved in the effects seen. We conducted two randomised crossover studies each in 24 (12 of each sex) healthy subjects assessing the acute effects of dietary nitrate (250 ml beetroot juice) or potassium nitrate capsules (KNO3, 8 mmol) vs placebo control on platelet reactivity. Inorganic nitrate ingested either from a dietary source or via supplementation raised circulating nitrate and nitrite levels in both sexes and attenuated ex vivo platelet aggregation responses to ADP and, albeit to a lesser extent, collagen but not epinephrine in male but not female volunteers. These inhibitory effects were associated with a reduced platelet P-selectin expression and elevated platelet cGMP levels. In addition, we show that nitrite reduction to NO occurs at the level of the erythrocyte and not the platelet. In summary, our results demonstrate that inorganic nitrate ingestion, whether via the diet or through supplementation, causes a modest decrease in platelet reactivity in healthy males but not females. Our studies provide strong support for further clinical trials investigating the potential of dietary nitrate as an adjunct to current antiplatelet therapies to prevent atherothrombotic complications. Moreover, our observations highlight a previously unknown sexual dimorphism in platelet reactivity to NO and intimate a greater dependence of males on the NO-soluble guanylate cyclase pathway in limiting thrombotic potential.

Dietary nitrate ameliorates pulmonary hypertension: cytoprotective role for endothelial nitric oxide synthase and xanthine oxidoreductase

BACKGROUND

Pulmonary hypertension (PH) is a multifactorial disease characterized by increased pulmonary vascular resistance and right ventricular failure; morbidity and mortality remain unacceptably high. Loss of nitric oxide (NO) bioactivity is thought to contribute to the pathogenesis of PH, and agents that augment pulmonary NO signaling are clinically effective in the disease. Inorganic nitrate (NO(3)(-)) and nitrite (NO(2)(-)) elicit a reduction in systemic blood pressure in healthy individuals; this effect is underpinned by endogenous and sequential reduction to NO. Herein, we determined whether dietary nitrate and nitrite might be preferentially reduced to NO by the hypoxia associated with PH, and thereby offer a convenient, inexpensive method of supplementing NO functionality to reduce disease severity.

METHODS AND RESULTS

Dietary nitrate reduced the right ventricular pressure and hypertrophy, and pulmonary vascular remodeling in wild-type mice exposed to 3 weeks of hypoxia; this beneficial activity was mirrored largely by dietary nitrite. The cytoprotective effects of dietary nitrate were associated with increased plasma and lung concentrations of nitrite and cGMP. The beneficial effects of dietary nitrate and nitrite were reduced in mice lacking endothelial NO synthase or treated with the xanthine oxidoreductase inhibitor allopurinol.

CONCLUSIONS

These data demonstrate that dietary nitrate, and to a lesser extent dietary nitrite, elicit pulmonary dilatation, prevent pulmonary vascular remodeling, and reduce the right ventricular hypertrophy characteristic of PH. This favorable pharmacodynamic profile depends on endothelial NO synthase and xanthine oxidoreductase -catalyzed reduction of nitrite to NO. Exploitation of this mechanism (ie, dietary nitrate/nitrite supplementation) represents a viable, orally active therapy for PH.

Serious neutropenia following etanercept administration in a 62 years female patient of rheumatoid arthritis

Tumor necrosis factor (TNF) plays an important role in the inflammatory process of RA and the resulting joint pathology. Etanercept is a member of anti TNF family which is indicated in patients with moderate to severe active rheumatoid arthritis either alone or in combination with MTX. Very few cases of neutropenia with etanercept treatment have been reported worldwide so far. The mechanism of etanercept induced neutropenia is not yet established. We report a case of 62 year female patient, developing etanercept induced neutropenia after 1 month of starting treatment. The absolute neutrophil count (ANC) came down to 150/microl on the 6th day of diagnosis. Bone marrow examination revealed a maturation arrest of granulocytic cells. Other marrow components were normal. Causality assessment of adverse drug reactions was done as per Naranjo's Algorithm. It was a probable ADR. We propose the possible mechanism of neutropenia is bone marrow toxicity. This is contrary to a previous case report which suggested peripheral consumption of neutrophil as a cause of neutropenia. Recently, there are some reports of leukemia and other hematological malignancies associated with the use of etanercept and in those conditions neutropenia could be the first manifestation. Neither product label of the drug nor US FDA warns for periodic blood investigation during etanercept therapy. There is a definite need for total and differential count estimation at the beginning and regular interval during etanercept treatment to rule out possibilities of neutropenia.

Percutaneous transtracheal jet ventilation as a guide to tracheal intubation in severe upper airway obstruction from supraglottic oedema

We report two cases of severe upper airway obstruction caused by supraglottic oedema secondary to adult epiglottitis and Ludwig's angina. In the former case, attempts to intubate with a direct laryngoscope failed but were successful once percutaneous transtracheal jet ventilation (PTJV) had been instituted. In the case with Ludwig's angina, PTJV was employed as a pre-emptive measure and the subsequent tracheal intubation with a direct laryngoscope was performed with unexpected ease. In both cases recognition of the glottic aperture was made feasible with PTJV by virtue of the fact that the high intra-tracheal pressure from PTJV appeared to lift up and open the glottis. The escape of gas under high pressure caused the oedematous edges of the glottis to flutter, which facilitated the identification of the glottic aperture. We believe that the PTJV should be considered in the emergency management of severe upper airway obstruction when this involves supraglottic oedema.