Relationship between obstructive sleep apnea and pulmonary hypertension: past, present and future

INTRODUCTION

Obstructive sleep apnea (OSA) is a widely prevalent condition with consequent multiple organ systems complications. There is consensus that OSA is associated with negative effects on pulmonary hemodynamics but whether it contributes to development of clinical pulmonary hypertension (PH) is unclear.

AREAS COVERED

In this review, we (1) highlight previous studies looking into the possible bidirectional association of OSA and PH, focusing on those that explore clinical prognostic implications, (2) explore potential pathophysiology, (3) discuss the new metrics in OSA, (4) describe endo-phenotyping of OSA, (5) recommend possible risk assessment and screening pathways.

EXPERT OPINION

Relying only on symptoms to consider a sleep study in PH patients is a missed opportunity to detect OSA, which, if present and not treated, can worsen outcomes. The potential prognostic role of sleep study metrics such as oxygen desaturation index (ODI), hypoxic burden (HB) and ventilatory burden (VB) in OSA should be studied in prospective trials to identify patients at risk for PH. AHI alone has not provided clarity. In those with PH, we should consider replacing ambulatory overnight pulse oximetry (OPO) with home sleep studies (HST). In PH patients, mild OSA should be sufficient to consider PAP therapy.

Home and nearby nature: Uncovering relational flows between domestic and natural spaces in three countries during COVID-19

This paper addresses the role of living spaces, neighborhood environments, and access to nearby nature in shaping individual experiences of health and well-being during the first wave of the COVID-19 pandemic. Key data is drawn from the GreenCOVID study across Spain, England and Ireland. The survey gathered contextual information about home environments, neighborhood spaces, and access to nature elements, and standardized measures of health and wellbeing between April and July 2020 (n = 3,127). The paper used qualitative data from the survey to document flows between home and nearby nature. These were framed as barriers/mediators with specific focus on differing interpretations of home as both trap and refuge, with additional dimensions of loss, disruption and interruption shaping the broad responses to the pandemic. By contrast nearby nature was an enabler/moderator of health and wellbeing, offering healthy flows between home and nature as well as respite and additional health-enabling factors. Differences were identified between the three countries but important commonalities emerged too, recognising the role nature plays as an asset both within and immediately beyond the home. The use of flow as metaphor also recognises the importance of embodiment and the elastic nature of connections between home and nearby nature for wellbeing. More broadly, flow provides a valuable way to trace affective relational geographers to develop a wider understanding of assemblages of health during pandemics.

Older people’s aspirations for the aftermath of COVID-19: Findings from the WISE study

Background

For many older people around the globe, the COVID-19 pandemic has highlighted accessibility issues and pervasive inequalities across multiple social, economic and health dimensions. The aim of the present study is to explore older people's perspectives about what we should learn from this pandemic and how to build a better future.

Methods

The Well-being, Interventions and Support during Epidemics (WISE) study is an exploratory qualitative project that has collected information from 46 individuals aged 65+, who live in Irish community settings. Data collection included in-depth interviews over the phone or videoconference platforms. Analysis is ongoing utilizing NVivo12 to identify themes and linkages within a socio-ecological framework.

Preliminary Results

Findings indicate that at the macrosystems level, several participants expect policymakers and researchers to commit to challenging ageist misconceptions of a homogeneous aging experience- such as the notion that older people are merely recipients of care with a high degree of needs. Upon reflection of their experiences with shelter-in-place restrictions and its consequences, at the exosystem level, many respondents called for older voices to be consulted in public health decisions and included in decision-making bodies. Concerning the microsystem, participants referred policymakers should further develop natural and built environments that enable physical, mental and social well-being for all. Cutting across all levels, participants advised for stronger political will and accountability, as they recognized some of their concerns had been addressed in past policies but were not being implemented.

Conclusions

Our preliminary findings are applicable to the Irish context but also provide relevant insights for those interested in creating inclusive age-friendly societies across the globe. Embracing this shared vision would provide significant opportunities to address present and future public health challenges.

Key messages

Older people are very diverse, so it is necessary to move on from one size fits all approaches.

Age-friendly societies are multifaceted endeavours that must include older voices at their core and build upon intergenerational solidarity.

Unilateral branch pulmonary artery stenting in tetralogy of fallot improves ventricular function

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): NIHR

Background

Pulmonary artery stenosis (PAS) occurs commonly in patients with tetralogy of fallot (ToF). Cardiac function and especially left ventricular longitudinal strain has been identified as an important prognostic factor for long term survival in ToF. The clinical relevance of unilateral PAS to long-term bi-ventricular function is poorly understood.

Purpose

We sought to evaluate the effect of resolving unilateral pulmonary artery obstruction on right and left ventricular performance.

Methods

We prospectively included 40 patients with TOF between 2016 and 2020, 20 who underwent unilateral PAS stenting and as comparison 20 who underwent surgical pulmonary valve replacement (PVR). MRI data was acquired during routine clinical care before and around 6-12 months after the procedure. 4 PAS patients attended additional research scans acquiring ventricular 4D flow MRI data. 4D flow MRI data was compared to the average kinetic energy curve of 10 age-matched healthy volunteers.

Results

Of the 20 patients undergoing PAS, 2 also underwent percutaneous PVR and were excluded from the comparison analysis. All patients in the PAs group showed an improvement in branch PA flow differential post procedure. Patients undergoing PAS were younger than those undergoing PVR (median 12 vs 19 years, p < 0.001). Other baseline anatomical and functional parameters including right ventricular (RV) volume indexed to body surface are (RVEDV/BSA) were comparable (pre PAS median 151 [122,170] vs pre PVR 162 [140,191]; p = 0.217). While in the PVR group the right ventricular volumes reduced in both end-diastole and end-systole, in the PAS group RV function improved due to reduced end-systolic volume with largely stable end-diastolic volumes.

Changes in the left ventricle (LV) were even more interesting. In the PVR group ejection fraction improved due to an increase in end-diastolic volume with no improvement in ventricular longitudinal strain. In contrast, in the PAS group LV ejection fraction improved by a reduction in end-systolic volume and the PAS group showed a small but significant improvement in LV longitudinal strain. In addition, ¾ patients undergoing 4D flow MRI assessment showed LV kinetic energy curve more similar to the healthy volunteer averaged  LV kinetic energy curve after PAS. The 4th patient already had a near normal LV kinetic energy curve prior to PAS.

Conclusion

Unilateral PAS does not alter RV end-diastolic volumes but improves RV function. LV ejection fraction improvement is similar to that seen after PVR, but importantly PAS also improved LV longitudinal strain. This suggests that PAS might positively influence long term morbidity and mortality risk in ToF patients, but a larger multi-centre long term follow-up study is needed to confirm this.

228 Resilience, Mindset and Burnout of Healthcare Workers During the COVID-19 Pandemic

Introduction

We investigated the impact of the Biopsychosocial challenges associated with the COVID-19 Pandemic on the Healthcare Workforce, exploring the impact on and relationship between Healthcare Workers’ Mindset, Resilience and Burnout.

Method

An electronic survey was distributed to Healthcare Workers through Professional Associations' websites and social media. The survey contained demographic questions, a Burnout Inventory, a General Resilience scale, a scale to assess for Resilience during the Pandemic, as well as an Adapted Dweck Mindset instrument to measure Mindset as related to Workplace Environment and Resilience. Univariate and multivariate analysis was undertaken to examine the relationship between these factors.

Results

1,370 healthcare workers completed the questionnaire. 58.5%, 25.4%, 28.5% reported having Burnout, Low General Resilience and Low COVID Resilience, respectively. Burnout was significantly associated with Fixed Mindset, Low General Resilience and Low COVID Resilience. Resilience Training was found to be protective for Burnout.

Conclusions

The COVID-19 Pandemic has led to a higher proportion of HCWs experiencing Burnout than previously reported. Our findings demonstrate that HCWs with Low Resilience and Fixed Mindsets are more likely to experience Burnout, suggesting that, in combination with improved institutional support, there is a role for personalised Resilience and Mindset Training, in helping reduce the proportion of HCW Burnout.

Canadian perspective on managing multiple myeloma during the COVID-19 pandemic: lessons learned and future considerations

The coronavirus disease 2019 (covid-19) pandemic caused by the novel severe acute respiratory syndrome coronavirus 2 has necessitated changes to the way patients with chronic diseases are managed. Given that patients with multiple myeloma are at increased risk of covid-19 infection and related complications, national bodies and experts around the globe have made recommendations for risk mitigation strategies for those vulnerable patients. Understandably, because of the novelty of the virus, many of the proposed risk mitigation strategies have thus far been reactionary and cannot be supported by strong evidence. In this editorial, we highlight some of the risk mitigation strategies implemented at our institutions across Canada during the first wave of covid-19, and we discuss the considerations that should be made when managing patients during the second wave and beyond.

Iatrogenic air embolism

Air embolism should be treated promptly with high fraction of supplemental oxygen and repositioning to help facilitate reabsorption of the air bubble. Hyperbaric oxygen therapy should be given to those with severe disease.

Demodex: a skin resident in man and his best friend

Demodex mites are microscopic arachnids found in the normal skin of many mammals. In humans, it is well established that Demodex mite density is higher in patients with the skin condition rosacea, and treatment with acaricidal agents is effective in resolving symptoms. However, pathophysiology of rosacea is complex and multifactorial. In dogs, demodicosis is a significant veterinary issue, particularly the generalized form of the disease which can be fatal if untreated. In each species, clinical and molecular studies have shown that the host's immunological interactions with Demodex mites are an important, but not fully understood, aspect of how Demodex can live in the skin either as a harmless commensal organism or as a pathogenic agent. This review outlines the role of Demodex mites in humans and dogs, considering morphology, prevalence, symptoms, diagnosis, histology treatment and pathogenesis.

Evaluation of Demodex mite viability using motility and scattered light intensity

Demodex mites have been suggested to have a role in various cutaneous and ocular disorders pathogenesis, such as rosacea or blepharitis. Evaluation of potential treatments with anti-Demodex effects is difficult because the viability of living mites needs to be evaluated during their exposure to the agent being tested. Mite viability is currently based solely on their observed movement. However, this method of assessing viability has significant limitations as mites may be resting, immobile or paralysed at any given observation point giving the observer a false impression of the organism's death. To overcome this limitation we evaluated a new quantitative method of evaluating the viability of Demodex mites by using scattered light intensity (SLI). We demonstrated that when combined with observation of mite motility, SLI provided increased accuracy of the evaluation of viability of mites being studied. This new viability assay will help address the technical challenges of mite viability experiments. Accurate evaluation of mite viability will enhance mite biology research and allow for more accurate in vitro toxicity assays of proposed anti-mite agents.

Evaluation of subcutaneous rituximab administration on Canadian systemic therapy suites

Background

Non-Hodgkin lymphoma (nhl) is the most common hematologic malignancy. Diffuse large B-cell lymphoma (dlbcl) and follicular lymphoma (fl) constitute 55% of new nhl cases and are initially treated with rituximab-based chemoimmunotherapy. Relative to intravenous (IV) rituximab, a subcutaneous (sc) formulation approved in 2016 has comparable pharmacokinetics, efficacy, and safety, and a greatly reduced administration time; it is also preferred by patients. The objective of the present study was to estimate the effect (on systemic therapy suite time and on the costs of drug acquisition and administration) of implementing sc rituximab in the initial chemoimmunotherapy for fl and dlbcl over 3 years in the Canadian market.

Methods

An Excel (Microsoft Corporation, Redmond, WA, U.S.A.)-based model was created with a population size based on epidemiologic data and current rituximab use, duration of use considering initial therapy, time savings for sc rituximab administration from published studies, costs from standard Canadian sources, and assumed uptake in implementing provinces of 65%, 75%, and 80% over 3 years. Key parameters and sensitivity analysis values were validated by clinical experts located in various Canadian jurisdictions. Costs are reported in 2017 Canadian dollars from the perspective of the health care system.

Results

More than 3 years after implementation of sc rituximab, we estimated that 5762 Canadians would be receiving sc rituximab, resulting in savings of 128,715 hours in systemic therapy suite time and approximately $40 million in drug and administration costs. Sensitivity analyses suggest that the model is most sensitive to sc market uptake, number of induction therapy cycles, and eligible patients.

Conclusions

Subcutaneous administration of rituximab can significantly reduce systemic therapy suite time and achieve substantial savings in drug and administration costs.

Comparison of Advanced Imaging Resources, Radiology Workforce, and Payment Methodologies between the United States and Canada

The purpose of this Practice Perspectives was to review the United States and Canadian approaches to health care access and payment for advanced imaging. The historical background, governmental role, workforce, coding, payment, radiologic challenges, cost, resource intensity, and overall outcomes in longevity are reviewed.

Low magnesium intake is associated with increased knee pain in subjects with radiographic knee osteoarthritis: data from the Osteoarthritis Initiative

OBJECTIVE

As magnesium mediates bone and muscle metabolism, inflammation, and pain signaling, we aimed to evaluate whether magnesium intake is associated with knee pain and function in radiographic knee osteoarthritis (OA).

METHODS

We investigated the associations between knee pain/function metrics and magnesium intake from food and supplements in 2548 Osteoarthritis Initiative cohort participants with prevalent radiographic knee OA (Kellgren-Lawrence score ≥2). Magnesium intake was assessed by Food Frequency Questionnaire (FFQ) at baseline. WOMAC and Knee Injury and Osteoarthritis Outcome Score (KOOS) scores were reported annually with total follow up of 48 months. Analyses used linear mixed models.

RESULTS

Among participants with baseline radiographic knee OA the mean total magnesium intake was 309.9 mg/day (SD 132.6) for men, and 287.9 mg/day (SD 118.1) for women, with 68% of men and 44% of women below the estimated average requirement. Subjects with lower magnesium intake had worse knee OA pain and function scores, throughout the 48 months (P < 0.001). After adjustment for age, sex, race, body mass index (BMI), calorie intake, fiber intake, pain medication use, physical activity, renal insufficiency, smoking, and alcohol use, lower magnesium intake remained associated with worse pain and function outcomes (1.4 points higher WOMAC and 1.5 points lower KOOS scores for every 50 mg of daily magnesium intake, P < 0.05). Fiber intake was an effect modifier (P for interaction <0.05). The association between magnesium intake and knee pain and function scores was strongest among subjects with low fiber intake.

CONCLUSION

Lower magnesium intake was associated with worse pain and function in knee OA, especially among individuals with low fiber intake.

Clinical audit effectively bridges the evidence-practice gap in chronic subdural haematoma management

BACKGROUND

Placement of a subdural drain after drainage of chronic subdural haematoma (CSDH) has been shown to reduce the rate of recurrence in several randomised controlled trials (RCT). The most recently published RCT was from Cambridge, UK, in 2009. Despite class I evidence for the use of subdural drains, it is unclear whether these results have been translated into clinical practice. In this clinical audit we review the use of subdural drains in our institution before and after the publication of the 2009 RCT results.

METHODS

A longitudinal retrospective study was performed on all adults having burr holes for CSDH between January 2009 and January 2014. Case notes were analysed to determine subdural drain use, re-operation for CSDH recurrence and post-operative complications. The audit loop was closed with data collected from August 2015 to January 2016.

RESULTS

Thirty-one per cent of patients had subdural drains placed at operation. Drain placement was associated with lower reoperation rates (8% vs. 17%, p = 0.021) without increasing complication rates. Drain usage doubled after publication of the Santarius et al. (2009) trial but we observed persisting and significant variability in drain utilisation by supervising consultants. The use of drains in the department increased from 35% to 75% of all cases after presentation of these results.

CONCLUSIONS

The use of subdural drains in our unit reduced recurrence rates following drainage of CSDH and reproduced the results of a 2009 clinical trial. Although the use of subdural drains doubled in the post-trial epoch, significant variability remains in practice. Clinical audit provided an effective tool necessary to drive the implementation of subdural drain placement in our unit.

Can Creatinine Height Index Predict Weaning and Survival Outcomes in Patients on Prolonged Mechanical Ventilation After Critical Illness?

OBJECTIVE

Malnutrition is common in chronic critically ill patients on prolonged mechanical ventilation (PMV) and may affect weaning. The creatinine height index (CHI), which reflects lean muscle mass, is regarded as the most accurate indicator of malnutrition. The objective of this study was to determine the impact of CHI in comparison with other traditional nutritional indices on successful weaning and survival in patients on PMV after critical illness.

METHODS

Records of 167 patients on PMV following critical illness, admitted for weaning, were reviewed. Parameters studied included age, gender, body mass index (BMI), percentage ideal body weight (%IBW), total protein, albumin, prealbumin, hemoglobin (Hb), and cause of respiratory failure. Number successfully weaned and number discharged alive and time to wean and time to discharge alive were determined from records. The CHI was calculated from 24-hour urine creatinine using a standard formula. Unpaired 2-sample t test was performed to determine the association between the studied nutritional parameters and outcomes. Predictive value of studied parameters for successful weaning and survival was determined by multivariate logistic regression analysis to model dichotomous outcome of successful weaning and survival.

RESULTS

Mean age was 68 ± 14 years, 49% were males, 64% were successfully weaned, and 65.8% survived. Total protein, Hb, and CHI had a significant impact on successful weaning. Weight, %IBW, BMI, and CHI had a significant effect on survival. Of all parameters, CHI was most strongly predictive of successful weaning and survival.

CONCLUSIONS

The CHI is a strong predictor of successful weaning and survival in patients on PMV.

Reactivation of pulmonary tuberculosis following local radiation therapy of prostate cancer

In this report, we describe the case of an 81-year-old male with reactivation tuberculosis following local radiation therapy for prostate cancer. The patient was asymptomatic except for an unintentional 20-pound weight loss and was incidentally found to have a pulmonary infiltrate in the right upper lobe on imaging for shoulder pain. The medical history was not able for recently treated prostate cancer. After further investigation, the patient was determined to have Mycobacterium tuberculosis infection. It is important to have a high level of suspicion for reactivation tuberculosis in patients with a pulmonary infiltrate following radiation therapy due to the impact of radiation on the host's immune system. We will review the literature on reactivation tuberculosis following radiation therapy and explore the mechanism of immunosuppression in this process. To our knowledge, this is the first reported case of tuberculosis reactivation following local radiation therapy for prostate cancer.

Mitochondrial DNA variation in Karkar Islanders

We analyzed 375 base pairs (bp) of the first hypervariable region (HVS-I) of the mitochondrial DNA (mtDNA) control region and intergenic COII/tRNALys 9-bp deletion from 47 Karkar Islanders (north coast of Papua New Guinea) belonging to the Waskia Papuan language group. To address questions concerning the origin and evolution of this population we compared the Karkar mtDNA haplotypes and haplogroups to those of neighbouring East Asians and Oceanic populations. The results of the phylogeographic analysis show grouping in three different clusters of the Karkar Islander mtDNA lineages: one group of lineages derives from the first Pleistocene settlers of New Guinea-Island Melanesia, a second set derives from more recent arrivals of Austronesian speaking populations, and the third contains lineages specific to the Karkar Islanders, but still rooted to Austronesian and New Guinea-Island Melanesia populations. Our results suggest (i) the absence of a strong association between language and mtDNA variation and, (ii) reveal that the mtDNA haplogroups F1a1, M7b1 and E1a, which probably originated in Island Southeast Asia and may be considered signatures of Austronesian population movements, are preserved in the Karkar Islanders but absent in other New Guinea-Island Melanesian populations. These findings indicate that the Karkar Papuan speakers retained a certain degree of their own genetic uniqueness and a high genetic diversity. We present a hypothesis based on archaeological, linguistic and environmental datasets to argue for a succession of (partial) depopulation and repopulation and expansion events, under conditions of structured interaction, which may explain the variability expressed in the Karkar mtDNA.

Tositumomab and Iodine I 131 Tositumomab for Recurrent Indolent and Transformed B-Cell Non-Hodgkin’s Lymphoma

Purpose

An open-label phase II study was conducted at two centers to establish the efficacy and safety of tositumomab and iodine I 131 tositumomab at first or second recurrence of indolent or transformed indolent B-cell lymphoma.

Patients and Methods

A single dosimetric dose was followed at 7 to 14 days by the patient-specific administered radioactivity required to deliver a total body dose of 0.75 Gy (reduced to 0.65 Gy for patients with platelets counts of 100 to 149 × 109/L). Forty of 41 patients received both infusions.

Results

Thirty-one of 41 patients (76%) responded, with 20 patients (49%) achieving either a complete (CR) or unconfirmed complete remission [CR(u)] and 11 patients (27%) achieving a partial remission. Response rates were similar in both indolent (76%) and transformed disease (71%). The overall median duration of remission was 1.3 years. The median duration of remission has not yet been reached for those patients who achieved a CR or CR(u). Eleven patients continue in CR or CR(u) between 2.6+ and 5.2+ years after therapy. Therapy was well tolerated; hematologic toxicity was the principal adverse event. Grade 3 or 4 anemia, neutropenia, and thrombocytopenia were observed in 5%, 45%, and 32% of patients, respectively. Secondary myelodysplasia has occurred in one patient. Four patients developed human antimouse antibodies after therapy. Five of 38 assessable patients have developed an elevated thyroid-stimulating hormone; treatment with thyroxine has been initiated in one patient.

Conclusion

High overall and CR rates were observed after a single dose of tositumomab and iodine I 131 tositumomab in this patient group. Toxicity was modest and easily managed.