Is breathing frequency a potential means for monitoring exercise intensity in people with atrial fibrillation and coronary heart disease when heart rate is mitigated?

PURPOSE

Moderate-intensity aerobic exercise is safe and beneficial in atrial fibrillation (AF) and coronary heart disease (CHD). Irregular or rapid heart rates (HR) in AF and other heart conditions create a challenge to using HR to monitor exercise intensity. The purpose of this study was to assess the potential of breathing frequency (BF) to monitor exercise intensity in people with AF and CHD without AF.

METHODS

This observational study included 30 AF participants (19 Male, 70.7 ± 8.7 yrs) and 67 non-AF CHD participants (38 Male, 56.9 ± 11.4 yrs). All performed an incremental maximal exercise test with pulmonary gas exchange.

RESULTS

Peak aerobic power in AF ( V ˙ O2peak; 17.8 ± 5.0 ml.kg-1.min-1) was lower than in CHD (26.7 ml.kg-1.min-1) (p < .001). BF responses in AF and CHD were similar (BF peak: AF 34.6 ± 5.4 and CHD 36.5 ± 5.0 breaths.min-1; p = .106); at the 1st ventilatory threshold (BF@VT-1: AF 23.2 ± 4.6; CHD 22.4 ± 4.6 breaths.min-1; p = .240). % V ˙ O2peak at VT-1 were similar in AF and CHD (AF: 59%; CHD: 57%; p = .656).

CONCLUSION

With the use of wearable technologies on the rise, that now include BF, this first study provides an encouraging potential for BF to be used in AF and CHD. As the supporting data are based on incremental ramp protocol results, further research is required to assess BF validity to manage exercise intensity during longer bouts of exercise.

The Effect of Sedentary Behaviour on Cardiorespiratory Fitness: A Systematic Review and Meta-Analysis

BACKGROUND

Cardiorespiratory fitness (CRF) is an important indicator of current and future health. While the impact of habitual physical activity on CRF is well established, the role of sedentary behaviour (SB) remains less understood.

OBJECTIVE

We aimed to determine the effect of SB on CRF.

METHODS

Searches were conducted in MEDLINE, Embase, PsycINFO, CINAHL and SPORTDiscus from inception to August 2022. Randomised controlled trials, quasi-experimental studies and cohort studies that assessed the relationship between SB and CRF were eligible. Narrative syntheses and meta-analyses summarised the evidence, and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) certainty was based on evidence from randomised controlled trials.

RESULTS

This review included 18 studies that focused on youth (four randomised controlled trials, three quasi-experimental studies, 11 cohort studies) and 24 on adult populations (15 randomised controlled trials, five quasi-experimental studies, four cohort studies). In youth and adults, evidence from randomised controlled trials suggests mixed effects of SB on CRF, but with the potential for interventions to improve CRF. Quasi-experimental and cohort studies also support similar conclusions. Certainty of evidence was very low for both age groups. A meta-analysis of adult randomised controlled trials found that interventions targeting reducing SB, or increasing physical activity and reducing SB, had a significant effect on post-peak oxygen consumption (mean difference = 3.16 mL.kg-1.min-1, 95% confidence interval: 1.76, 4.57).

CONCLUSIONS

Evidence from randomised controlled trials indicates mixed associations between SB and CRF, with the potential for SB to influence CRF, as supported by meta-analytical findings. Further well-designed trials are warranted to confirm the relationship between SB and CRF, explore the effects of SB independent from higher intensity activity, and investigate the existence of such relationships in paediatric populations.

CLINICAL TRIAL REGISTRATION

PROSPERO CRD42022356218.

A quality improvement strategy to reduce unintended extubation in the very low birth weight infant-A case report

BACKGROUND

Unintended extubations remain a common complication across neonatal intensive care units, with very low birthweight infants being the most vulnerable of them all. Ongoing efforts across different institutions exist with the goal of reducing the rate of unintended extubations to keep a median rate of <2 events per 100 ventilator days as defined by the Vermont Oxford Network. Our objective was to reduce unintended extubations in the very low birthweight infant in a large delivery hospital to ≤2/100 ventilator days.

METHODS

A collaborative group was formed between two academic health institutions targeting training and implementation of the Children's National unintended extubation system, focusing on endotracheal tube securement methods and surveillance protocols.

RESULTS

The unintended extubation rate decreased from 3.23 to 0.64 per 100 ventilator days. Changes were implemented from 2018-2020 with a sustained reduction in the unintended extubation rate of 1.54 per 100 ventilator days. Most events occurred between 12 : 00 pm -4 : 00 pm and the commonest cause was spontaneous (25%) followed by dislodgment during repositioning (19%).

CONCLUSION

Very low birth weight infants present a challenge to endotracheal tube maintenance due to their developmental and anatomical changes during their neonatal intensive care unit stay. Successful reduction of unintended extubations in the very low birthweight infant can be achieved by adaptation of successful protocols for older infants.

Screening for sarcopenia with SARC-F in older patients hospitalized with cardiovascular disease

OBJECTIVES

SARC-F ≥ 4 points are used for detecting sarcopenia; however, finding a lower SARC-F cut-off value may lead to early detection of sarcopenia. We investigated the SARC-F score with the highest sensitivity and specificity value to identify sarcopenia in older patients with cardiovascular disease (CVD). Motor performances were also examined for each SARC-F score.

METHODS

This retrospective cross-sectional study examined the sensitivity and specificity of every 1-point increase in SARC-F score to predict sarcopenia. Eligible participants included patients with CVD (≥ 65 years old) who were admitted for acute CVD treatment and participated in cardiac rehabilitation. Patients completed the SARC-F questionnaire and the sarcopenia assessment. Areas under the curves (AUCs) were investigated for the ability to predict sarcopenia. Multivariable linear regression was used to compare the mean value of physical functions (e.g., Walking speed, leg strength, and 6-minute walking distance) of each SARC-F score.

RESULTS

A total of 1066 participants (63.8% male; median age: 78 years) were included. Sarcopenia was present in 401 patients. SARC-F cut-off ≥ 2 presented the optimal balance between sensitivity (68.3%) and specificity (55.6%) to detect sarcopenia (the AUCs = 0.658; 95% confidence interval: 0.625-0.691). Even when the patients have low scores (1-3), increasing every 1 point of SARC-F score was associated with lower physical functions, such as lower muscle strength and shorter walking distance (all p < 0.001).

CONCLUSIONS

SARC-F cut-off ≥ 2 was optimal for screening sarcopenia, and even a low SARC-F score is helpful in finding earlier sarcopenia and low physical function in patients with CVD.

Impact of the COVID-19 pandemic on pediatric faculty: a report from nine academic institutions

BACKGROUND

The COVID-19 pandemic affected home and work routines, which may exacerbate existing academic professional disparities. Objectives were to describe the impact of the pandemic on pediatric faculty's work productivity, identify groups at risk for widening inequities, and explore mitigation strategies.

METHODS

A cross-sectional study of faculty members was conducted at nine U.S. pediatric departments. Responses were analyzed by demographics, academic rank, and change in home caregiving responsibility.

RESULTS

Of 5791 pediatric faculty members eligible, 1504 (26%) completed the survey. The majority were female (64%), over 40 years old (60%), and assistant professors (47%). Only 7% faculty identified as underrepresented in medicine. Overall 41% reported an increase in caregiving during the pandemic. When comparing clinical, administrative, research, and teaching activities, faculty reported worse 1-year outlook for research activities. Faculty with increased caregiving responsibilities were more likely to report concerns over delayed promotion and less likely to have a favorable outlook regarding clinical and research efforts. Participants identified preferred strategies to mitigate challenges.

CONCLUSIONS

The COVID-19 pandemic negatively impacted pediatric faculty productivity with the greatest effects on those with increased caregiving responsibilities. COVID-19 was particularly disruptive to research outlook. Mitigation strategies are needed to minimize the long-term impacts on academic pediatric careers.

IMPACT

The COVID-19 pandemic most negatively impacted work productivity of academic pediatric faculty with caregiving responsibilities. COVID-19 was particularly disruptive to short-term (1-year) research outlook among pediatric faculty. Faculty identified mitigation strategies to minimize the long-term impacts of the pandemic on academic pediatric career pathways.

Evaluation of the analytical performance of the 15-minute point-of-care DASH™ SARS-CoV-2 RT-qPCR test

Accurate and timely diagnosis for COVID-19 diagnosis allows highly effective antiviral medications to be prescribed. The DASH™ Rapid PCR System is a sample-to-answer point-of-care platform combining state-of-the-art PCR kinetics with sequence specific hybridization. The platform's first assay, the DASH™ SARS-CoV-2/S test for anterior nares direct swab specimens, received FDA Emergency Use Authorization in March 2022 for point-of-care use. Here we report the analytical characteristics of the assay including limit of detection, dynamic range, and robustness of SARS-CoV-2 variant detection. The limit of detection was determined by testing swabs contrived with one hundred copies of wild type or Omicron BA.5 virus and detecting 20/20 and 19/20, respectively. The dynamic range was assessed with contrived swabs containing 102-106 copies; the log-linear relationship between Cq and copy input was plotted, and the qPCR efficiency calculated from the slope of the line was 101.4%. Detection of seven SARS-CoV-2 variants was demonstrated.

Spontaneous Coronary Artery Dissection Across the Health Care Pathway: A National, Multicenter, Patient-Informed Investigation

BACKGROUND

Clinical practice guidelines for the management and convalescence of patients with spontaneous coronary artery dissection (SCAD) have yet to be developed. The targeted content, delivery, and outcomes of interventions that benefit this population remain unclear. Patient-informed data are required to substantiate observational research and provide evidence to inform and standardize clinical activities.

METHODS AND RESULTS

Patients diagnosed with SCAD (N=89; 86.5% women; mean age, 53.2 years) were purposively selected from 5 large tertiary care hospitals. Patients completed sociodemographic and medical questionnaires and participated in an interview using a patient-piloted semistructured interview guide. Interviews were transcribed and subjected to framework analysis using inductive and then deductive coding techniques. Approximately 1500 standard transcribed pages of interview data were collected. Emotional distress was the most commonly cited precipitating factor (56%), with an emphasis on anxiety symptoms. The awareness and detection of SCAD as a cardiac event was low among patients (35%) and perceived to be moderate among health care providers (55%). Health care providers' communication of the prognosis and self-management of SCAD were perceived to be poor (79%). Postevent psychological disorders among patients were evident (30%), and 73% feared recurrence. Short- and longer-term follow-up that was tailored to patients' needs was desired (72%). Secondary prevention programming was recommended, but there were low completion rates of conventional cardiac rehabilitation (48%), and current programming was deemed inadequate.

CONCLUSIONS

This early-stage, pretrial research has important implications for the acute and long-term management of patients with SCAD. Additional work is required to validate the hypotheses generated from this patient-oriented research.

Cluster Sets to Prescribe Interval Resistance Training: A Potential Method to Optimise Resistance Training Safety, Feasibility and Efficacy in Cardiac Patients

The integration of resistance training for cardiac patients leads to important health outcomes that are not optimally obtained with aerobic exercise; these include an increase in muscle mass, maintenance of bone mineral density, and improvements in muscular fitness parameters. Despite the proliferation of evidence supporting resistance exercise in recent decades, the implementation of resistance training is underutilised, and prescription is often sub-optimal in cardiac patients. This is frequently associated with safety concerns and inadequate methods of practical exercise prescription. This review discusses the potential application of cluster sets to prescribe interval resistance training in cardiac populations. The addition of planned, regular passive intra-set rest periods (cluster sets) in resistance training (i.e., interval resistance training) may be a practical solution for reducing the magnitude of haemodynamic responses observed with traditional resistance training. This interval resistance training approach may be a more suitable option for cardiac patients. Additionally, many cardiac patients present with impaired exercise tolerance; this model of interval resistance training may be a more suitable option to reduce fatigue, increase patient tolerance and enhance performance to these workloads. Practical strategies to implement interval resistance training for cardiac patients are also discussed. Preliminary evidence suggests that interval resistance training may lead to safer acute haemodynamic responses in cardiac patients. Future research is needed to determine the efficacy and feasibility of interval resistance training for health outcomes in this population.

Commentary: Is Wearable Fitness Technology a Medically Approved Device? Yes and No

Wearable technologies, i.e., activity trackers and fitness watches, are extremely popular and have been increasingly integrated into medical research and clinical practice. To assist in optimizing health, wellness, or medical care, these devices require collaboration between researchers, healthcare providers, and wearable technology companies in order to clarify their clinical capabilities and educate consumers on the utilities and limitations of the wide-ranging wearable devices. Interestingly, activity trackers and fitness watches often track both health/wellness and medical information within the same device. In this commentary, we will focus our discussions regarding wearable technology on (1) defining and explaining the technical differences between tracking health, wellness, and medical information; (2) providing examples of health and wellness compared to medical tracking; (3) describing the potential medical benefits of wearable technology and its applications in clinical populations; and (4) elucidating the potential risks of wearable technology. We conclude that while wearable devices are powerful and informative tools, further research is needed to improve its clinical applications.

Prognostic value of liver damage assessed through direct bilirubin levels and skeletal muscle weakness in patients with heart failure

BACKGROUND

Patients with heart failure (HF) often exhibit signs of liver dysfunction such as high bilirubin concentrations, leading to physical dysfunction and poor prognosis. Nevertheless, the relationship between direct bilirubin (DB), a fractionated form of total bilirubin, and dynapenia remains unclear, as does their effect on prognosis.

OBJECTIVES

This study investigated the association between DB concentrations and dynapenia in patients with HF.

METHODS

This retrospective study included patients with HF who underwent assessments for DB concentration, and handgrip and leg strengths to evaluate dynapenia and muscle weakness, respectively. Multiple logistic regression analyses examined the associations of DB with muscle strength and dynapenia. Additionally, we examined the prognostic value of comorbid high DB concentrations (≥0.5 mg/dL) and dynapenia. The endpoint was all-cause mortality.

RESULTS

Of 853 inpatients, high DB was identified in 147 and dynapenia in 377 (44.2%). Multiple regression analysis revealed that high DB was independently associated with decreased muscle strength (handgrip strength, P = 0.027; leg strength, P = 0.002). After adjusting for covariates, the high DB group (odds ratio: 1.800, 95% confidence interval [CI]: 1.203-2.695, P = 0.004) had a significantly higher risk of dynapenia than the low DB group. During the follow-up period, 189 patients died (median, 1.77 years; interquartile range, 0.64-3.81 years). The risk of death was significantly higher in the high DB and dynapenia group, even after adjusting for HF severity (hazard ratio: 2.610, 95% CI: 1.680-4.051, P<0.001).

CONCLUSIONS

High DB is associated with muscle weakness, and when combined with dynapenia, DB predicts a poorer prognosis in patients with HF.

Exercise training reduces circulating cytokines in male patients with coronary artery disease and type 2 diabetes: A pilot study

Low-grade inflammation is central to coronary artery disease (CAD) and type 2 diabetes (T2D) and is reduced by exercise training. The objective of this study was to compare the anti-inflammatory potential of moderate-to-vigorous intensity continuous training (MICT) and high-intensity interval training (HIIT) in patients with CAD with or without T2D. The design and setting of this study is based on a secondary analysis of registered randomized clinical trial NCT02765568. Male patients with CAD were randomly assigned to either MICT or HIIT, with subgroups divided according to T2D status (non-T2D-HIIT n = 14 and non-T2D-MICT n = 13; T2D-HIIT n = 6 and T2D-MICT n = 5). The intervention was a 12-week cardiovascular rehabilitation program consisting of either MICT or HIIT (twice weekly sessions) and circulating cytokines measured pre- and post-training as inflammatory markers. The co-occurrence of CAD and T2D was associated with increased plasma IL-8 (p = 0.0331). There was an interaction between T2D and the effect of the training interventions on plasma FGF21 (p = 0.0368) and IL-6 (p = 0.0385), which were further reduced in the T2D groups. An interaction between T2D, training modalities, and the effect of time (p = 0.0415) was detected for SPARC, with HIIT increasing circulating concentrations in the control group, while lowering them in the T2D group, and the inverse occurring with MICT. The interventions also reduced plasma FGF21 (p = 0.0030), IL-6 (p = 0.0101), IL-8 (p = 0.0087), IL-10 (p < 0.0001), and IL-18 (p = 0.0009) irrespective of training modality or T2D status. HIIT and MICT resulted in similar reductions in circulating cytokines known to be increased in the context of low-grade inflammation in CAD patients, an effect more pronounced in patients with T2D for FGF21 and IL-6.

Factors influencing the conduction of confidential conversations with adolescents in the emergency department: A multicenter, qualitative analysis

BACKGROUND

Health care providers (HCPs) in the emergency department (ED) frequently must decide whether to conduct or forego confidential conversations with adolescent patients about sensitive topics, such as those related to mental health, substance use, and sexual and reproductive health. The objective of this multicenter qualitative analysis was to identify factors that influence the conduct of confidential conversations with adolescent patients in the ED.

METHODS

In this qualitative study, we conducted semistructured interviews of ED HCPs from five academic, pediatric EDs in distinct geographic regions. We purposively sampled HCPs across gender, professional title, and professional experience. We used the Theoretical Domains Framework (TDF) to develop an interview guide to assess individual and system-level factors affecting HCP behavior regarding the conduct of confidential conversations with adolescents. Enrollment continued until we reached saturation. Interviews were recorded, transcribed, and coded by three investigators based on thematic analysis. We used the coded transcripts to collaboratively generate belief statements, which are first-person statements that reflect shared perspectives.

RESULTS

We conducted 38 interviews (18 physicians, 11 registered nurses, five nurse practitioners, and four physician assistants). We generated 17 belief statements across nine TDF domains. Predominant influences on having confidential conversations included self-efficacy in speaking with adolescents alone, wanting to address sexual health complaints, maintaining patient flow, experiencing parental resistance and limited space, and having inadequate resources to address patient concerns and personal preconceptions about patients. Perspectives divided between wanting to provide focused medical care related only to their chief complaint versus self-identifying as a holistic medical HCP.

CONCLUSIONS

The factors influencing the conduct of confidential conversations included multiple TDF domains, elucidating how numerous intersecting factors influence whether ED HCPs address sensitive adolescent health needs. These data suggest methods to enhance and facilitate confidential conversations when deemed appropriate in the care of adolescents in the ED.

SARC-F predicts poor motor function, quality of life, and prognosis in older patients with cardiovascular disease and cognitive impairment

OBJECTIVES

We investigated whether SARC-F scores were associated with motor function, quality of life (QOL) related to physical function, and prognosis in older patients with cardiovascular disease (CVD) and cognitive impairment.

METHODS

This was a retrospective cross-sectional cohort study. The study population consisted of 408 patients with CVD (≥60 years old) who completed the SARC-F questionnaire and Mini-Cog, a cognitive function test, at discharge. Sarcopenia was defined as a total SARC-F score ≥ 4 points. Patients who were cognitively-preserved (Mini-Cog score ≥ 3 points) were excluded. Patients completed the handgrip strength, leg strength, usual gait speed, 6-minute walking distance, short physical performance battery score, and 36-item Short-Form Health Survey Physical Functioning (SF-36PF) tests before discharge. Associations of SARC-F with physical function, QOL, and prognoses (i.e., composite of all-cause death and emergency CVD rehospitalization and the number of CVD rehospitalizations) were investigated.

RESULTS

Sarcopenia (SARC-F score ≥ 4 points) was associated with poorer motor function test outcomes and SF-36PF scores (all P < 0.001). The correlations remained significant after adjusting for comorbidities (e.g., anemia, prior heart failure, and renal dysfunction). Sarcopenia was also associated with a poorer prognosis (hazard ratio: 1.574; 95 % confidence interval [CI], 1.011-2.445) and an increased risk of CVD rehospitalization (incidence rate ratio: 1.911; 95 % CI, 1.312-2.782) after adjusting for comorbidities.

CONCLUSIONS AND IMPLICATIONS

In older patients with CVD and cognitive impairment, the SARC-F questionnaire may be a simple and inexpensive tool for identifying patients with decreased motor function and a poor prognosis.

Examining the Role of Physical Activity Interventions in Modulating Androgens and Cardiovascular Health in Postmenopausal Women: A Narrative Review

A growing body of literature has examined the role of physical activity (PA) in modifying the effects of estrogen withdrawal on cardiovascular health in postmenopausal women, but the impact of PA on androgens is less clear. Changes in androgen concentrations following regular PA may improve cardiovascular health. This narrative review summarizes the literature assessing the impact of PA interventions on androgens in postmenopausal women. The association between changes in androgen concentrations and cardiovascular health following PA programs is also examined. Randomized controlled trials were included if they (i) implemented a PA program of any type and duration in postmenopausal women and (ii) measured changes in androgen concentrations. Following PA interventions, no changes in androstenedione, conflicting changes in dehydroepiandrosterone/dehydroepiandrosterone-sulfate, and increases in sex hormone-binding globulin concentrations were found. Total testosterone decreased following aerobic PA but increased after resistance training. Most aerobic PA interventions led to reductions in free testosterone. A combination of caloric restriction and/or fat loss enhanced the influence of PA on most androgens. Evidence exploring the relationship between changes in androgens and cardiovascular health indicators was scarce and inconsistent. PA has shown promise in modifying the concentrations of some androgens (free and total testosterone, sex hormone-binding globulin), and remains a well-known beneficial adjuvant option for postmenopausal women to manage their cardiovascular health. Fat loss influences the effect of PA on androgens, but the synergistic role of PA and androgens on cardiovascular health merits further examination. Many research gaps remain regarding the relationship between PA, androgens, and cardiovascular disease in postmenopausal women.

Effect of High-Intensity Interval Training in Patients With Atrial Fibrillation: A Randomized Clinical Trial

IMPORTANCE

Patients with atrial fibrillation (AF) experience poor functional capacity and quality of life (QOL). High-intensity interval training (HIIT) has been shown to elicit greater improvements in functional capacity and QOL compared with moderate to vigorous intensity continuous training (MICT) in other cardiovascular populations, yet HIIT remains understudied in AF.

OBJECTIVE

To compare the effects of 12 weeks of HIIT and MICT-based cardiovascular rehabilitation (CR) on functional capacity and general QOL in patients with persistent and permanent AF. Disease-specific QOL, resting heart rate (HR), time in AF, and physical activity (PA) levels were also assessed.

DESIGN, SETTING, AND PARTICIPANTS

This randomized clinical trial, conducted between November 17, 2015, and February 4, 2020, at a tertiary-care cardiovascular health center in Ottawa, Canada, recruited 94 patients with persistent and permanent AF.

INTERVENTIONS

High-intensity interval training (23 minutes: two 8-minute interval training blocks of 30-second work periods at 80%-100% of peak power output interspersed with 30-second recovery) or CR (60 minutes: continuous aerobic conditioning within 67%-95% of peak HR and 12-16 of 20 ratings of perceived exertion) twice weekly for 12 weeks.

MAIN OUTCOMES AND MEASURES

The primary outcomes were changes in functional capacity (6-minute walk test [6MWT] distance) and general QOL (Short Form 36) from baseline to 12 weeks' follow-up. Secondary outcomes included changes in disease-specific QOL (Atrial Fibrillation Severity Scale), resting HR, time in AF, and PA levels. An intention-to-treat analysis was used to compare changes between groups.

RESULTS

Of the 94 patients who consented, 86 participated (mean [SD] age, 69 [7] years; 57 [66.3%] men). No significant differences in improvements in 6MWT distance (mean [SD], 21.3 [34.1] vs 13.2 [55.2] m; P = .42) and general QOL (Physical Component Summary, 0.5 [6.1] vs 1.1 [4.9] points; P = .87) between HIIT and CR were observed. No significant differences in improvements in disease-specific QOL (AF symptoms: -1.7 [4.3] vs -1.5 [4] points, P = .59), resting HR (-3.6 [10.6] vs -2.9 [12.4] beats per minute, P = .63), and moderate to vigorous PA levels (37.3 [93.4] vs 14.4 [125.7] min/wk; P = .35) between HIIT and CR were detected. Participants attended a mean (SD) of 18.3 (6.1) (75.1%) HIIT sessions and 20.0 (4.5) (83.4%) CR sessions (P = .36).

CONCLUSIONS AND RELEVANCE

In this randomized clinical trial, twice-weekly 23-minute HIIT was as efficacious as twice-weekly 60-minute CR in improving functional capacity, general and disease-specific QOL, resting HR, and PA levels in patients with persistent and permanent AF.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02602457.

A case series of acute responses to high-intensity interval training in four males with permanent atrial fibrillation

Background

Atrial fibrillation (AF) is a serious medical condition and a burgeoning patient population. Chronic exercise training, including high-intensity interval training (HIIT), has been shown to improve symptoms and quality of life in patients with AF. Yet, the acute responses to HIIT in this population remain understudied, leaving clinicians and patients hesitant about prescribing and engaging in high-intensity exercise, respectively.

Case summary

This case series describes acute exercise responses [i.e. power output, heart rate (HR), blood pressure (BP), ratings of perceived exertion (RPE), symptoms] to 10 weeks (3 days/week) of HIIT. Participants were four white males (58–80 years old) with permanent AF, co-morbidities (diabetes, coronary artery disease, Parkinson’s disease), and physical limitations. The increases in HR and BP during HIIT were modest across all participants, regardless of age and medication use. Differences in RPE were observed; the oldest participant perceived the sessions as more challenging despite a lower HR response. All patients complied with the HIIT prescription of 80–100% of peak power output by week 4. No adverse events were reported.

Discussion

Patients’ concerns regarding high-intensity exercise may discourage them from participating in HIIT, our results demonstrated no abnormal HR or BP (e.g. hypotension) responses during HIIT or cool-down. These findings align with the typical exercise responses noted in other cardiovascular populations. Notwithstanding the high metabolic demands of HIIT, male patients with permanent AF tolerated HIIT without problem. Further investigation of HIIT as an approach to enable those with AF to recover physical capacity and minimize symptomatology is warranted.

Optimal cutoff values for physical function tests in elderly patients with heart failure

Six-minute walk distance (6MWD) of 300 and 400 m are important targets of functional capacity. The present study was performed to determine cutoff values of physical function associated with 6MWD < 300 m and < 400 m in elderly patients with heart failure (HF). 6MWD, handgrip strength, quadriceps isometric strength (QIS), one-leg standing time (OLST), and 5-times sit-to-stand (5STS) before hospital discharge were evaluated in 1001 patients > 65 years (median age, 75: interquartile range, 71-80, 607 men) with HF. 6MWD < 300 and < 400 m were seen in 323 patients (32.3%) and 658 patients (65.7%), respectively. Handgrip strength, QIS, OLST, and 5STS were associated with 6MWD < 300 and < 400 m, respectively (P < 0.001). The cutoff values of handgrip strength, QIS, OLST, and 5STS were 18.9 kg, 35.0% body mass (BM), 9.1 s, and 9.5 s for 6MWD < 300 m, and 21.9 kg, 40.0% BM, 12.0 s, and 8.8 s for < 400 m, respectively. The cutoff values of physical function could be used to set cardiac rehabilitation goals and limiting determinants of reduced functional capacity in a clinical setting in elderly patients with HF.

The Prevalence of Metabolic Dysfunction-Associated Fatty Liver Disease and Its Association with Physical Function and Prognosis in Patients with Acute Coronary Syndrome

It is believed that patients with acute coronary syndrome (ACS) are at an increased risk of nonalcoholic fatty liver disease (NAFLD), which can lead to sarcopenia and physical dysfunction. However, the relationship between metabolic dysfunction-associated fatty liver disease (MAFLD) and physical dysfunction and prognosis remains unclear. We investigated the prevalence of MAFLD in patients with ACS to assess the relationship between MAFLD and muscle strength, walking speed, and 6-min walking distance (6 MWD). We reviewed patients with ACS who were assessed for hepatic steatosis using the fatty liver index, and the results were further assessed to determine the presence of MAFLD. Among 479 enrolled hospitalized patients, MAFLD was identified in 234 (48.9%) patients. Multiple regression analysis revealed that MAFLD was independently associated with lower leg strength, gait speed, and 6 MWD (leg strength, p = 0.020; gait speed, p = 0.003 and 6 MWD, p = 0.011). Furthermore, in multivariate Poisson regression models after adjustment for clinical confounding factors, combined MAFLD and reduced physical functions were significantly associated with a higher incidence of clinical events. MAFLD is common in hospitalized patients with ACS and is associated with impaired physical function. Also, the coexistence of MAFLD and lower physical function predict the incidence of clinical events in patients with ACS.

Sex-specific associations of fat mass and muscle mass with cardiovascular disease risk factors in adults with type 2 diabetes living with overweight and obesity: secondary analysis of the Look AHEAD trial

Background

Distinguishable sex differences exist in fat mass and muscle mass. High fat mass and low muscle mass are independently associated with cardiovascular disease (CVD) risk factors in people living with type 2 diabetes; however, it is unknown if the association between fat mass and CVD risk is modified by muscle mass, or vice versa. This study examined the sex-specific interplay between fat mass and muscle mass on CVD risk factors in adults with type 2 diabetes living with overweight and obesity.

Methods

Dual-energy X-ray absorptiometry (DXA) measures were used to compute fat mass index (FMI) and appendicular muscle mass index (ASMI), and participants were separated into high-fat mass vs. low-fat mass and high-muscle mass vs. low-muscle mass. A two-way analysis of covariance (ANCOVA: high-FMI vs. low-FMI by high-ASMI vs. low-ASMI) was performed on CVD risk factors (i.e., hemoglobin A1C [A1C]; high-density lipoprotein cholesterol; low-density lipoprotein cholesterol; triglycerides; systolic and diastolic blood pressure; cardiorespiratory fitness, depression and health related-quality of life [HR-QoL]) at baseline and following a 1-year intensive lifestyle intervention (ILI) for females and males separately, with a primary focus on the fat mass by muscle mass interaction effects.

Results

Data from 1,369 participants (62.7% females) who completed baseline DXA were analyzed. In females, there was a fat mass by muscle mass interaction effect on A1C (p = 0.016) at baseline. Post-hoc analysis showed that, in the low-FMI group, A1C was significantly higher in low-ASMI when compared to high-ASMI (60.3 ± 14.1 vs. 55.5 ± 13.5 mmol/mol, p = 0.023). In the high-FMI group, there was no difference between high-ASMI and low-ASMI (56.4 ± 12.5 vs. 56.5 ± 12.8 mmol/mol, p = 0.610). In males, only high-FMI was associated with higher A1C when compared to low-FMI (57.1 ± 14.4 vs. 54.2 ± 12.0 mmol/mol, p = 0.008) at baseline. Following ILI, there were significant fat mass by muscle mass interaction effects on changes in the mental component of HR-QoL in males.

Conclusion

Considering that A1C predicts future CVD, strategies to lower A1C may be especially important in females with low fat and low muscle mass living with type 2 diabetes. Our results highlight the complicated and sex-specific contribution of fat mass and muscle mass to CVD risk factors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01468-x.

The Physical Activity Levels and Sitting Time of Adults Living with Atrial Fibrillation – The CHAMPLAIN-AF Study

Background

Methods

Results

Conclusions

Acute Care Utilization and Health Care Expenditures in Medicaid-Enrolled Children

OBJECTIVES

Although recent health care reform efforts have focused on minimizing high cost health care utilization, the relationship between acute care use and health care expenditures among certain vulnerable populations such as Medicaid-insured children remains poorly understood. We sought to evaluate the association between acute care utilization and health care expenditures and to identify characteristics associated with high spending.

METHODS

We performed a retrospective cohort study of Medicaid-enrolled children 1-21 years old from 1/1/2016 to 12/31/2016. Children were categorized by acute care use (including emergency department and urgent care visits) as 0, 1, 2, 3, and 4 or more visits. Our main outcomes were annualized spending, total per-member-per-year spending, and acute care-related per-member-per-year spending.

RESULTS

There were 5.1 million Medicaid-enrolled children that comprised the study cohort, accounting for US $32.6 billion in total spending. Children with 4 or more acute care visits were more likely to be younger than 2 years or older than 14 years, female, and have a chronic condition. Children with 4 or more acute care visits consisted of only 4% of the cohort but accounted for 15% (US $4.7 billion) of the total spending. Increasing acute care visits were associated with increasing total annualized spending in adjusted analyses (P < 0.001). This association was disproportionately observed in older age groups and children without chronic medical conditions.

CONCLUSIONS

Medicaid spending for children increases with increasing acute care use; this trend was disproportionately observed in older age groups and children without chronic medical conditions. Improved understanding of factors contributing to frequent acute care utilization and disproportionate spending is needed to potentially reduce unnecessary health care costs in these pediatric populations.

A Pediatric Patient With Ascites, Proteinuria, and Thrombocytopenia: A Rare Presentation for a Common Illness

ABSTRACT

A 7-year-old female patient presented to our pediatric emergency department with 5 days of fever, sore throat, abdominal pain, vomiting, headache, and 2 days of periorbital swelling. Her initial laboratory evaluation revealed a negative monospot test, neutropenia, atypical lymphocytosis, and thrombocytopenia in addition to transaminitis and proteinuria. An abdominal ultrasound obtained identified hepatosplenomegaly, moderate ascites, acalculous cholecystitis, and a distended appendix with periappendiceal fluid. She was admitted to gastroenterology for further management with antibiotics and surgery and hematology consults. Ultimately, Epstein-Barr virus polymerase chain reaction was positive. This case highlights an atypical presentation of Epstein-Barr virus and the collaborative approach to diagnosis.

Reliance on Acute Care Settings for Health Care Utilization: A Comparison of Adolescents With Younger Children

OBJECTIVE

Because a goal of the Affordable Care Act was to increase preventive care and reduce high-cost care, the objective of this study was to evaluate current health care use and reliance on acute care settings among Medicaid-enrolled children.

METHODS

This was a retrospective cohort study of the 2015 Truven Marketscan Medicaid claims database among children 0 to 21 years old with at least 11 months of continuous enrollment. We calculated adjusted probabilities of health care use (any health care use and ≥1 health maintenance visit) and high acute care reliance (ratio of emergency department or urgent care visits to all health care visits >0.33) by age and compared use between adolescents and younger children using multivariable logistic regression.

RESULTS

Of the 5,182,540 Medicaid-enrolled children, 18.9% had no health care visits and 47.3% had 1 or more health maintenance visit in 2015. Both health care use and health maintenance visits decreased with increasing age (P < 0.001). Compared with younger children (0-10 years old), adolescents were more likely to have no interaction with the health care system [adjusted odds ratio (aOR), 2.20; 95% confidence interval (CI), 2.19-2.21] and less likely to have health maintenance visits (aOR, 0.40; 0.39-0.40). High acute care reliance was associated with increasing age, with adolescents having greater odds of high acute care reliance (aOR, 1.08; 1.08-1.09).

CONCLUSIONS

Medicaid-enrolled adolescents have low rates of health care use and have high reliance on acute care settings. Further investigation into adolescent-specific barriers to health maintenance care and drivers for acute care is warranted.

Moving Together While Staying Apart: Practical Recommendations for 24-Hour Home-Based Movement Behaviours for Those With Cardiovascular Disease

The novel coronavirus disease 2019 is a global public health crisis that disproportionately affects those with preexisting conditions. Cardiovascular disease (CVD) is the leading cause of death worldwide and many key CVD risk factors are modifiable (e.g., physical inactivity, sedentary behaviour, obesity). To limit the spread of coronavirus 2019, most governments have implemented restrictions and recommended staying at home, reducing social contact to a select and exclusive few, and limiting large gatherings. Such public health constraints may have unintended, negative health consequences on 24-hour movement behaviours. The primary purpose of this review is to provide practical at-home recommendations for sedentary time, sleep, and physical activity in those living with CVD. Adults with CVD will benefit from practical recommendations to reduce sedentary time, increase purposeful exercise, and maintain optimal sleep patterns while being at home and adhering to public health restrictions. Our recommendations include the following: (i) self-monitoring sitting time; (ii) engaging in 2-3 days per week of purposeful exercise for those with low exercise capacity and > 3 days per week for those with moderate-to-high exercise capacity; (iii) self-monitoring exercise intensity through the use of scales or wearable devices; (iv) maintaining a regular sleep schedule; and (v) moving daily. Clinicians should be aware that clear communication of the importance of limiting prolonged sedentary time, engaging in regular physical activity and exercise, and ensuring optimal sleep in association with the provision of clear, comprehensible, and practical advice is fundamental to ensuring that those living with CVD respond optimally to the challenges posed by the pandemic.

Work-related factors predict changes in physical activity among nurses participating in a web-based worksite intervention: A randomized controlled trial

Background

Despite the numerous benefits associated with physical activity (PA), most nurses are not active enough and few interventions have been developed to promote PA among nurses. A secondary analysis of raw data from a single-centre, three-arm parallel-group randomized controlled trial was conducted to assess whether work-related characteristics and general mood states predict changes in total weekly moderate-to-vigorous intensity PA (MVPA) and average daily step-count among nurses participating in a 6-week web-based worksite intervention.

Methods

Seventy nurses (mean_age: 46.1 ± 11.2 years) were randomized to an individual-, friend-, or team-based PA challenge. Participants completed questionnaires pre- and post-intervention assessing work-related characteristics (i.e., shift schedule and length, number of hours worked per week, work role) and general mood states (i.e., tension, depression, anger, confusion, fatigue, vigour). Participants received a PA monitor to wear before and during the 6-week PA challenge, which was used to assess total weekly MVPA minutes and average daily step-count. Data were analyzed descriptively and using multilevel modeling for repeated measures.

Results

Change in total weekly MVPA minutes, but not change in average daily step-count, was predicted by shift schedule (rotating vs. fixed) by time (estimate = − 17.43, SE = 6.18, p = .006), and work role (clinical-only vs. other) by time (estimate = 18.98, SE = 6.51, p = .005). General mood states did not predict change in MVPA or change in average daily step-count.

Conclusions

Given that nurses who work rotating shifts and perform clinical work showed smaller improvements in MVPA, it may be necessary to consider work-related factors/barriers (e.g., time constraints, fatigue) and collaborate with nurses when designing and implementing MVPA interventions in the workplace.

Trial registration

ClinicalTrials.gov: NCT04524572. August 24, 2020. This trial was registered retrospectively. This study adheres to the CONSORT 2010 statement guidelines.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12912-021-00739-4.

Monitoring and adapting endurance training on the basis of heart rate variability monitored by wearable technologies: A systematic review with meta-analysis

OBJECTIVES

To systematically perform a meta-analysis of the scientific literature to determine whether the outcomes of endurance training based on heart rate variability (HRV) are more favorable than those of predefined training.

DESIGN

Systematic review and meta-analysis.

METHODS

PubMed and Web of Science were searched systematically in March of 2020 using keywords related to endurance, the ANS, and training. To compare the outcomes of HRV-guided and predefined training, Hedges' g effect size and associated 95% confidence intervals were calculated.

RESULTS

A total of 8 studies (198 participants) were identified comprising 9 interventions involving a variety of approaches. Compared to predefined training, most HRV-guided interventions included fewer moderate- and/or high-intensity training sessions. Fixed effects meta-analysis revealed a significant medium-sized positive effect of HRV-guided training on submaximal physiological parameters (g = 0.296, 95% CI 0.031 to 0.562, p = 0.028), but its effects on performance (g = 0.079, 95% CI -0.050 to 0.393, p = 0.597) and V̇O2peak (g = 0.171, 95% CI -0.213 to 0.371, p = 0.130) were small and not statistically significant. Moreover, with regards to performance, HRV-guided training was associated with fewer non-responders and more positive responders.

CONCLUSIONS

In comparison to predefined training, HRV-guided endurance training had a medium-sized effect on submaximal physiological parameters, but only a small and non-significant influence on performance and V̇O_2peak. There were fewer non-responders regarding performance with HRV-based training.

Cardiac Rehabilitation Following Percutaneous Coronary Intervention Is Associated With Superior Psychological Health and Quality of Life in Males but Not in Females

PURPOSE

Cardiac rehabilitation (CR) improves psychological health and health-related quality of life (HR-QoL). Yet, available evidence suggests that their degree of improvements following CR may depend on patient sex and the mode of revascularization. We examined the interplay between sex and mode of revascularization on the psychological health and HR-QoL of patients completing CR.

METHODS

We analyzed the longitudinal records of patients who completed a 3-mo outpatient CR program following coronary revascularization. Levels of anxiety and depression were measured by the Hospital Anxiety and Depression Scale and HR-QoL was measured by the Medical Outcomes Study Short Form-36 before and after CR. A two-by-two analysis of covariance (females vs males by coronary artery bypass graft surgery [CABG] vs percutaneous coronary intervention [PCI]) was used to examine the sex-by-revascularization procedure interaction effect on changes in psychological health and HR-QoL.

RESULTS

Of the 278 participants (age: 65 ± 9 yr) included in the analysis, 191 (69%) underwent PCI and 55 (20%) were females. Following CR, there was a significant sex-by-revascularization procedure interaction effect on anxiety (P = .033) and mental HR-QoL (mental component summary [MCS]; P = .040). Following CABG, females and males showed similar improvements in anxiety (-1.3 ± 3.4 vs -1.1 ± 3.6 points, P = .460) and MCS scores (5.4 ± 8.9 vs 4.5 ± 8.7 points, P = .887); following PCI, females experienced worse anxiety levels and mental component summary scores while males showed improvements (anxiety: +1.0 ± 3.8 vs -1.3 ± 3.8 points, P = .002; MCS: -1.6 ± 9.3 vs + 4.4 ± 8.9 points, P = .008, respectively). There was no interaction effect on depression.

CONCLUSIONS

Continued efforts are required to improve anxiety and mental HR-QoL in females treated with PCI participating in CR.

Sex differences in physical and mental health following high-intensity interval training in adults with cardiovascular disease who completed cardiac rehabilitation

This pre-post study examined sex-differences in peak aerobic power (V̇O2peak) and physical- and mental-health outcomes in adults with cardiovascular disease who completed high-intensity interval training (HIIT)-based cardiac rehabilitation. HIIT consisted of 25 minutes of alternating higher- (4×4 minutes 85-95% heart rate peak (HRpeak)) and lower- (3×3 minutes 60-70% HRpeak) intensity intervals twice weekly for 10 weeks. V̇O2peak estimated from a graded exercise test using the American College of Sports Medicine equation, body mass index (BMI), waist circumference, blood pressure, blood biomarkers and anxiety and depression were assessed at baseline and follow-up. Linear mixed-effects models for repeated measures were performed to examine differences over time between sexes. Of 140 participants (mean ± standard deviation: 58 ± 9 years), 40 were female. Improvements in V̇O2peak did not differ between sexes (interaction: p = 0.273, females: 28.4 ± 6.4 to 30.9 ± 7.6; males: 34.3 ± 6.3 to 37.4 ± 6.0 mL/kg/min). None of the time by sex interactions were significant. Significant main effects of time showed reductions in waist circumference, triglycerides, low-density lipoprotein (LDL), total cholesterol (TC)/high-density lipoprotein (HDL) and anxiety, and increases in V̇O2peak and HDL from baseline to follow-up. Significant main effects of sex revealed smaller V̇O2peak, BMI and waist circumference, and higher LDL, TC and HDL in females than males. HIIT led to similar improvements in estimated V̇O2peak (females: 8.8%, males: 9.0%) and additional health outcomes between sexes. Novelty: HIIT-based cardiac rehabilitation led to similar improvements in estimated V̇O2peak and other physical and mental health outcomes between sexes. The number of sessions attended was high (>70%) and did not differ by sex. Both sexes showed good compliance with the exercise protocol (HR target).

The effects of high-intensity interval training, Nordic walking and moderate-to-vigorous intensity continuous training on functional capacity, depression and quality of life in patients with coronary artery disease enrolled in cardiac rehabilitation: A randomized controlled trial (CRX study)

BACKGROUND

Coronary artery disease (CAD) patients undergoing revascularization procedures often experience ongoing, diminished functional capacity, high rates of depression and markedly low quality of life (QoL). In CAD patients, studies have demonstrated that high-intensity interval training (HIIT) is superior to traditional moderate-to-vigorous intensity continuous training (MICT) for improving functional capacity, whereas no differences between Nordic walking (NW) and MICT have been observed. Mental health is equally as important as physical health, yet few studies have examined the impact of HIIT and NW on depression and QoL. The purpose of this randomized controlled trial (RCT) was to compare the effects of 12 weeks of HIIT, NW and MICT on functional capacity in CAD patients. The effects on depression severity, brain-derived neurotrophic factor (BDNF) and QoL were also examined.

METHODS

CAD patients who underwent coronary revascularization procedures were randomly assigned to: (1) HIIT (4 × 4-min of high-intensity work periods at 85%-95% peak heart rate [HR]), (2) NW (resting HR [RHR] + 20-40 bpm), or (3) MICT (RHR + 20-40 bpm) twice weekly for 12 weeks. Functional capacity (six-min walk test [6MWT]), depression (Beck Depression Inventory-II [BDI-II]), BDNF (from a blood sample), and general (Short-Form 36 [SF-36]) and disease-specific (HeartQoL) QoL were measured at baseline and follow-up. Linear mixed-effects models for repeated measures were used to test the effects of time, group and time × group interactions.

RESULTS

N = 135 CAD patients (aged 61 ± 7 years; male: 85%) participated. A significant time × group interaction (p = 0.042) showed greater increases in 6MWT distance (m) for NW (77.2 ± 60.9) than HIIT (51.4 ± 47.8) and MICT (48.3 ± 47.3). BDI-II significantly improved (HIIT: -1.4 ± 3.7, NW: -1.6 ± 4.0, MICT: -2.3 ± 6.0 points, main effect of time: p < 0.001) whereas BDNF concentrations did not change (HIIT: -2.5 ± 9.6, NW: -0.4 ± 7.7, MICT: -1.2 ± 6.4 ng/mL, main effect of time: p > 0.05). Significant improvements in SF-36 and HeartQoL values were observed (main effects of time: p < 0.05). HIIT, NW and MICT participants attended 17.7 ± 7.5, 18.3 ± 8.0 and 16.1 ± 7.3 of the 24 exercise sessions, respectively (p = 0.387).

CONCLUSIONS

All exercise programmes (HIIT, NW, MICT) were well attended, safe and beneficial in improving physical and mental health for CAD patients. NW was, however, statistically and clinically superior in increasing functional capacity, a predictor of future cardiovascular events.

Active and machine learning-based approaches to rapidly enhance microbial chemical production

In order to make renewable fuels and chemicals from microbes, new methods are required to engineer microbes more intelligently. Computational approaches, to engineer strains for enhanced chemical production typically rely on detailed mechanistic models (e.g., kinetic/stoichiometric models of metabolism)-requiring many experimental datasets for their parameterization-while experimental methods may require screening large mutant libraries to explore the design space for the few mutants with desired behaviors. To address these limitations, we developed an active and machine learning approach (ActiveOpt) to intelligently guide experiments to arrive at an optimal phenotype with minimal measured datasets. ActiveOpt was applied to two separate case studies to evaluate its potential to increase valine yields and neurosporene productivity in Escherichia coli. In both the cases, ActiveOpt identified the best performing strain in fewer experiments than the case studies used. This work demonstrates that machine and active learning approaches have the potential to greatly facilitate metabolic engineering efforts to rapidly achieve its objectives.

Viral reduction of human blood by ultraviolet A-photosensitized vitamin K5

Blood product transfusion can transmit viral pathogens. Pathogen reduction methods for blood products have been developed but, so far, are not available for whole blood. We evaluated if vitamin K5 (VK5) and ultraviolet A (UVA) irradiation could be used for virus inactivation in plasma and whole blood. Undiluted human plasma and whole blood diluted to 20% were spiked with high levels of vaccinia or Zika viruses. Infectious titers were measured by standard TCID₅₀ assay before and after VK5/UVA treatments. Up to 3.6 log of vaccinia and 3.2 log of Zika were reduced in plasma by the combination of 500 μM VK5 and 3 J/cm² UVA, and 3.1 log of vaccinia and 2.9 log of Zika were reduced in diluted human blood (20%) by the combination of 500 μM VK5 and 70 J/cm² UVA. At end of whole blood treatment, hemolysis increased from 0.18% to 0.41% but remained below 1% hemolysis, which is acceptable to the Food and Drug Administration for red cell transfusion products. No significant alteration of biochemical parameters of red blood cells occurred with treatment. Our results provide proof of the concept that a viral pathogen reduction method based on VK5/UVA may be developed for whole blood.

COVID-19 pandemic - Inequities and inequalities to exercise and their consequences on the physical and mental health of women with cardiovascular disease: recommendations on how to address the needs of women

The coronavirus disease (COVID-19) pandemic disproportionately affects those with pre-existing conditions and has exacerbated gender inequalities. Cardiovascular disease (CVD) is the leading cause of death among Canadian women. Exercise improves physical and mental health and CVD management. Amid the pandemic, women are experiencing an increase in caregiving responsibilities, job insecurities, and domestic violence creating competing demands for prioritizing their health. Recommendations on how to meet the unique needs of Canadian women with CVD through exercise are provided. Novelty: Exercise recommendations amid the pandemic for women with CVD need to be flexible, feasible, and fun.

Prognostic value of cardio-hepatic-skeletal muscle syndrome in patients with heart failure

Although heart failure (HF) and liver dysfunction often coexist because of complex cardiohepatic interactions, the association between liver dysfunction and physical dysfunction, and between coexistence of both and prognosis in HF patients remains unclear. We reviewed 895 patients with HF (mean age, 69.4 ± 14.2 years) who underwent liver function test using model for end-stage liver disease excluding international normalized ratio (MELD-XI) score and physical function test (grip strength, leg strength, gait speed, and 6-min walking distance [6MWD]). In the multiple regression analysis, MELD-XI score was independently associated with lower grip strength, leg strength, gait speed, and 6MWD (all P < 0.001). One hundred thirty deaths occurred over a median follow-up period of 1.67 years (interquartile range: 0.62–3.04). For all-cause mortality, patients with high MELD-XI scores and reduced physical functions were found to have a significantly higher mortality risk even after adjusting for several covariates (grip strength, hazard ratio [HR]: 3.80, P < 0.001; leg strength, HR: 4.65, P < 0.001; gait speed, HR: 2.49, P = 0.001, and 6MWD, HR: 5.48, P < 0.001). Liver dysfunction was correlated with reduced physical function. Moreover, the coexistence of lower physical function and liver dysfunction considerably affected prognosis in patients with HF.

A virtual platform to deliver ambulatory care for patients with atrial fibrillation

Background

There are little data on the use of virtual care for patients with arrhythmia. We evaluated a virtual clinic platform, in conjunction with specialist care, for patients with symptomatic atrial fibrillation (AF).

Methods

This was a prospective, observational cohort study evaluating an online educational and treatment platform, with a randomized sub-study examining the use of an ambulatory single-lead electrocardiogram heart monitor (AHM). Follow-up was 6 months. The main outcome was patients’ platform use; success was defined as 90% of patients using the platform at least once, and 75% using it at least twice. The primary outcome in the AHM sub-study was Atrial Fibrillation Symptom Severity (AFSS) score. Other outcomes included patient satisfaction questionnaires, quality of life, emergency department visits, and hospitalizations for AF.

Results

We enrolled 94 patients between July 2018 and May 2019; 83% of patients logged in at least once and 54.3% more than once. Patients who were older, were male, or had new-onset AF were more likely to log in to the platform. Satisfaction scores were high; 70%–94% of patients responded favorably. Quality-of-life scores improved at 3 and 6 months. In the AHM sub-study (n = 71), those who received an AHM had lower AFSS scores (least square mean difference -2.52, 95% CI -4.48 to -0.25, P = .03). There was no difference in emergency department visits or hospitalizations.

Conclusion

The online platform did not reach our feasibility target but was well received. Allocation of an AHM was associated with improved quality of life. Virtual AF care shows promise and should be evaluated in further research.

Cost-effectiveness of Sexually Transmitted Infection Screening for Adolescents and Young Adults in the Pediatric Emergency Department

IMPORTANCE

Adolescents and young adults compose almost 50% of all diagnosed sexually transmitted infection (STI) cases annually in the US. Given that these individuals frequently access health care through the emergency department (ED), the ED could be a strategic venue for examining the identification and treatment of STIs.

OBJECTIVE

To examine the cost-effectiveness of screening strategies for Chlamydia trachomatis and Neisseria gonorrhoeae (chlamydia and gonorrhea) in adolescents and young adults who seek acute care at pediatric EDs.

DESIGN, SETTING, AND PARTICIPANTS

This economic evaluation is a component of an ongoing, larger multicenter clinical trial at the Pediatric Emergency Care Applied Research Network. A decision analytic model, created using literature-based estimates for the key parameters, was developed to simulate the events and outcomes associated with 3 strategies for screening and testing chlamydial and gonococcal infections in individuals aged 15 to 21 years who sought acute care at pediatric EDs. Data sources included published (from January 1, 1997, to December 31, 2019) English-language articles indexed in MEDLINE, bibliographies in relevant articles, insurance claims data in the MarketScan database, and reimbursement payments from the Centers for Medicare and Medicaid Services. Because the events and outcomes were simulated, a hypothetical population of 10 000 ED visits by adolescents and young adults was used.

INTERVENTIONS

The 3 screening strategies were (1) no screening, (2) targeted screening, and (3) universally offered screening. Targeted screening involved the completion of a sexual health survey, which yielded an estimated STI risk (at risk, high risk, or low risk).

MAIN OUTCOMES AND MEASURES

Outcome metrics included cost (measured in 2019 US dollars) and the detection and successful treatment of STIs. The incremental cost-effectiveness ratio (ICER) of each strategy was calculated in a base case analysis. The ICER reflects the cost per case detected and successfully treated.

RESULTS

A 3.6% prevalence of chlamydia and gonorrhea was applied to a hypothetical population of 10 000 ED visits by adolescents and young adults. Targeted screening resulted in the detection and successful treatment of 95 of 360 STI cases (26.4%) at a cost of $313 063, and universally offered screening identified and treated 112 of 360 STI cases (31.1%) at a cost of $515 503. The ICER for targeted screening vs no screening was $6444, and the ICER for universally offered screening vs targeted screening was $12 139.

CONCLUSIONS AND RELEVANCE

This economic evaluation found that targeted screening and universally offered screening compared with no screening appeared to be cost-effective strategies for identifying and treating chlamydial and gonococcal infections in adolescents and young adults who used the ED for acute care. Universally offered screening was associated with detecting and successfully treating a higher proportion of STIs in this population.

Effectiveness of a Universally Offered Chlamydia and Gonorrhea Screening Intervention in the Pediatric Emergency Department

PURPOSE

Adolescents represent more than half of the newly diagnosed sexually transmitted infections in the U.S. annually. Emergency departments (EDs) may serve as an effective, nontraditional setting to screen for chlamydia/gonorrhea (CT/GC). The objective was to evaluate the effectiveness of a universally offered CT/GC screening program in two pediatric ED settings.

METHODS

This was a prospective, delayed start pragmatic study conducted over 18 months in two EDs within the same academic institution among ED adolescents aged 14-21 years with any chief complaint. Using a tablet device, adolescents were confidentially informed of CT/GC screening recommendations and were offered screening. If patients agreed to CT/GC testing, a clinical decision support tool was triggered to inform the provider and order testing. The main and key secondary outcomes were the proportion of CT/GC testing and positive CT/GC test results in each respective ED.

RESULTS

Both EDs experienced modest but statistically significant increases in CT/GC testing post- versus pre-intervention (main: 11.5% vs. 7.9%; confidence interval [CI]: 2.9-4.2; p < .0001 and satellite: 3.8% vs. 2.6%; 95% CI: .7-1.7; p < .0001). Among those tested, the positivity rate at the main ED did not significantly change post- versus pre-intervention (24.1% vs. 23.2%; 95% CI: -1.9 to 3.8; p = .71) but significantly decreased at the satellite ED (7.6% vs. 14.8%; 95% CI: -12.2 to -2.2; p = .01).

CONCLUSIONS

A universally offered screening intervention increased the proportion of adolescents who were tested at both EDs and the detection rates for CT/GC at the main ED, but patient acceptance of screening was low.

Meeting the Canadian strength training recommendations: Implications for the cardiometabolic, psychological and musculoskeletal health of nurses

AIM

To examine the proportion of nurses meeting the strength training recommendation and its associated cardiometabolic, psychological and musculoskeletal benefits.

BACKGROUND

Strength training targets poor physical and mental health often reported by nurses; however, it is unknown whether nurses are meeting the strength training guidelines.

METHODS

Nurses from 14 hospitals completed a 7-day physical activity log. Nurses were considered meeting the recommendation if they reported ≥2 strength training sessions per week. Cardiometabolic, psychological and musculoskeletal health, and levels of motivation were compared between nurses meeting and not meeting the guidelines.

RESULTS

Of the 307 nurses (94% female; age: 43 ± 12 years), 29 (9.4%) met the strength training recommendation. These nurses had lower body mass index (24.1 ± 2.6 vs. 27.3 ± 5.5 kg/m² , p = .007) and waist circumference (73.8 ± 8.3 vs. 81.1 ± 11.7 cm, p = .017); and higher vigour-activity (18.0 ± 5.8 vs. 15.6 ± 6.5 points, p = .046) and self-determined motivation (relative autonomic index: 54.9 ± 20.3 vs. 45.0 ± 23.8 points, p = .042) scores than nurses not meeting the recommendation.

CONCLUSION

While the proportion of nurses meeting the strength training recommendation was small (<10%), they had lower body mass and waist circumference, and higher vigour-activity.

IMPLICATIONS FOR NURSING MANAGEMENT

Strategies to increase the strength training engagement may improve the cardiometabolic health and increase vigour among nurses.

Daily physical activity and sedentary behaviour across occupational classifications in Canadian adults

BACKGROUND

Adults spend a large proportion of their day at work. Physical activity (PA) and sedentary behaviour (SB) have been shown to vary considerably between occupations. The objective of this study is to describe occupational differences in accelerometer-measured and self-reported PA and SB for Canadian full-time workers.

DATA AND METHODS

Using combined data from three cycles of the nationally representative Canadian Health Measures Survey (N = 4,080), three activity groups (high, intermediate, low) were created based on a composite ranking of accelerometer-derived steps, proportion of time spent sedentary (SED%) and moderate-to-vigorous intensity physical activity (MVPA) in bouts of ⋝10 minutes (MVPAbouted). Differences between groups were assessed for accelerometer-derived and self-reported PA and SB, and sociodemographic and clinical characteristics.

RESULTS

On average, Canadians employed in full-time work were sedentary for 68.9% of their day (95% confidence interval [CI]: 68.3% to 69.6%), took 8,984 steps per day (95% CI: 8,719 to 9,249) and accumulated 79.5 minutes per week of MVPAbouted (95% CI: 71.1 to 87.9). Among Canadians employed in full-time work, 18.5% met the Canadian Physical Activity Guidelines. The high-activity group took significantly more steps and had a lower SED%, but spent a higher proportion of time in light-intensity PA compared with the intermediate- and low-activity groups. No differences were observed for MVPA. The low-activity group reported more recreational and active travel-related PA and leisure reading, while those in the high-activity group reported more work and domestic PA and leisure screen time.

DISCUSSION

The majority of full-time working adults are not getting adequate MVPA and spend most of their day sedentary, regardless of occupation. Findings support workplace policies to improve MVPA levels among Canadian workers and to promote awareness for the potential benefit of occupation-specific messaging around PA and SB.

Predefined vs data-guided training prescription based on autonomic nervous system variation: A systematic review

Monitoring variations in the functioning of the autonomic nervous system may help personalize training of runners and provide more pronounced physiological adaptations and performance improvements. We systematically reviewed the scientific literature comparing physiological adaptations and/or improvements in performance following training based on responses of the autonomic nervous system (ie, changes in heart rate variability) and predefined training. PubMed, SPORTDiscus, and Web of Science were searched systematically in July 2019. Keywords related to endurance, running, autonomic nervous system, and training. Studies were included if they (a) involved interventions consisting predominantly of running training; (b) lasted at least 3 weeks; (c) reported pre- and post-intervention assessment of running performance and/or physiological parameters; (d) included an experimental group performing training adjusted continuously on the basis of alterations in HRV and a control group; and (e) involved healthy runners. Five studies involving six interventions and 166 participants fulfilled our inclusion criteria. Four HRV-based interventions reduced the amount of moderate- and/or high-intensity training significantly. In five interventions, improvements in performance parameters (3000 m, 5000 m, Loadmax, Tlim) were more pronounced following HRV-based training. Peak oxygen uptake ( V ˙ O 2 peak ) and submaximal running parameters (eg, LT1, LT2) improved following both HRV-based and predefined training, with no clear difference in the extent of improvement in V ˙ O 2 peak . Submaximal running parameters tended to improve more following HRV-based training. Research findings to date have been limited and inconsistent. Both HRV-based and predefined training improve running performance and certain submaximal physiological adaptations, with effects of the former training tending to be greater.

Motivation Predicts Change in Nurses' Physical Activity Levels During a Web-Based Worksite Intervention: Results From a Randomized Trial

Background

Low physical activity levels can negatively affect the health of nurses. Given the low physical activity levels reported by nurses, there is a clear need for brief and economical interventions designed to increase physical activity levels in this population. We developed a web-based intervention that used motivational strategies to increase nurses’ physical activity levels. The intervention provided the nurses with feedback from an activity monitor coupled with a web-based individual, friend, or team physical activity challenge.

Objective

In this parallel-group randomized trial, we examine whether nurses’ motivation at baseline predicted changes in objectively measured physical activity levels during the 6-week intervention.

Methods

The participants were 76 nurses (n=74, 97% female; mean age 46, SD 11 years) randomly assigned to 1 of 3 physical activity challenge conditions: (1) individual, (2) friend, or (3) team. The nurses completed a web-based questionnaire designed to assess motivational regulations for physical activity levels before the intervention and wore a Tractivity activity monitor before and during the 6-week intervention. We analyzed data using multilevel modeling for repeated measures.

Results

The nurses’ physical activity levels increased (linear estimate=10.30, SE 3.15; P=.001), but the rate of change decreased over time (quadratic estimate=−2.06, SE 0.52; P<.001). External and identified regulations (ß=−2.08 to 11.55; P=.02 to .04), but not intrinsic and introjected regulations (ß=−.91 to 6.29; P=.06 to .36), predicted changes in the nurses’ physical activity levels.

Conclusions

Our findings provide evidence that an intervention that incorporates self-monitoring and physical activity challenges can be generally effective in increasing nurses’ physical activity levels in the short term. They also suggest that drawing solely on organismic integration theory to predict changes in physical activity levels among the nurses participating in web-based worksite interventions may have been insufficient. Future research should examine additional personal (eg, self-efficacy) and occupational factors (eg, shift length and shift type) that influence physical activity levels to identify potential targets for intervention among nurses.

Trial Registration

ClinicalTrials.gov NCT04524572; https://clinicaltrials.gov/ct2/show/NCT04524572

Model-driven analysis of mutant fitness experiments improves genome-scale metabolic models of Zymomonas mobilis ZM4

Genome-scale metabolic models have been utilized extensively in the study and engineering of the organisms they describe. Here we present the analysis of a published dataset from pooled transposon mutant fitness experiments as an approach for improving the accuracy and gene-reaction associations of a metabolic model for Zymomonas mobilis ZM4, an industrially relevant ethanologenic organism with extremely high glycolytic flux and low biomass yield. Gene essentiality predictions made by the draft model were compared to data from individual pooled mutant experiments to identify areas of the model requiring deeper validation. Subsequent experiments showed that some of the discrepancies between the model and dataset were caused by polar effects, mis-mapped barcodes, or mutants carrying both wild-type and transposon disrupted gene copies-highlighting potential limitations inherent to data from individual mutants in these high-throughput datasets. Therefore, we analyzed correlations in fitness scores across all 492 experiments in the dataset in the context of functionally related metabolic reaction modules identified within the model via flux coupling analysis. These correlations were used to identify candidate genes for a reaction in histidine biosynthesis lacking an annotated gene and highlight metabolic modules with poorly correlated gene fitness scores. Additional genes for reactions involved in biotin, ubiquinone, and pyridoxine biosynthesis in Z. mobilis were identified and confirmed using mutant complementation experiments. These discovered genes, were incorporated into the final model, iZM4_478, which contains 747 metabolic and transport reactions (of which 612 have gene-protein-reaction associations), 478 genes, and 616 unique metabolites, making it one of the most complete models of Z. mobilis ZM4 to date. The methods of analysis that we applied here with the Z. mobilis transposon mutant dataset, could easily be utilized to improve future genome-scale metabolic reconstructions for organisms where these, or similar, high-throughput datasets are available.