Physical Activity Measurement Accuracy in Individuals With Chronic Lung Disease: A Systematic Review With Meta-Analysis of Method Comparison Studies

Risk Factors of Severe COVID-19: A Review of Host, Viral and Environmental Factors

The clinical course and outcome of COVID-19 are highly variable, ranging from asymptomatic infections to severe disease and death. Understanding the risk factors of severe COVID-19 is relevant both in the clinical setting and at the epidemiological level. Here, we provide an overview of host, viral and environmental factors that have been shown or (in some cases) hypothesized to be associated with severe clinical outcomes. The factors considered in detail include the age and frailty, genetic polymorphisms, biological sex (and pregnancy), co- and superinfections, non-communicable comorbidities, immunological history, microbiota, and lifestyle of the patient; viral genetic variation and infecting dose; socioeconomic factors; and air pollution. For each category, we compile (sometimes conflicting) evidence for the association of the factor with COVID-19 outcomes (including the strength of the effect) and outline possible action mechanisms. We also discuss the complex interactions between the various risk factors.

Measuring intensity during free-living physical activities in people with chronic obstructive pulmonary disease: a systematic literature review

BACKGROUND

Measuring intensity of physical activity (PA) is important to ensure safety and the effectiveness of PA interventions in chronic obstructive pulmonary disease (COPD).

OBJECTIVE

This systematic review identified which outcomes, outcome measures and instruments have been used to assess single free-living PA-related intensity in people with COPD and compared the intensity level (light, moderate, vigorous) obtained by different outcome measures.

METHODS

PubMed, Scopus, Web of Science, Cochrane Library and EBSCO were searched for original studies of COPD and assessing single free-living PA-related intensity were included. Agreement was calculated as the number of agreements between 2 measures [same intensity level]/ number of comparisons using both measures*100.

RESULTS

We included 43 studies (1282 people with COPD, mean age 66 years, 65% men, 49% FEV_1%pred) and identified 13 outcomes, 46 outcome measures and 22 instruments. The most-reported outcomes, outcome measures and instruments were dyspnoea with the Borg scale 0-10; cardiac function, via heart rate (HR) using HR monitors; and pulmonary gas exchange, namely oxygen consumption (VO₂), using portable gas analysers, respectively. The most frequently assessed PAs were walking and lifting, changing or moving weights/objects. Agreement between the outcome measures ranged from 0 (%VO_2peak vs metabolic equivalent of task [MET]; %HR_peak vs Fatigue Borg; MET vs walking speed) to 100% (%HR_reserve vs dyspnoea Borg; fatigue and exertion Borg vs walking speed). %VO_{2peak/reserve} elicited the highest intensity. Hence, Borg scores, %HR_reserve and MET may underestimate PA-related intensity.

CONCLUSIONS

Various methodologies are used to assess single free-living PA-related intensity and yield different intensity levels for the same PA. Future studies, further exploring the agreement between the different outcome measures of PA-related intensity and discussing their advantages, disadvantages and applicability in real-world settings, are urgent. These would guide future worldwide recommendations on how to assess single free-living PA-related intensity in COPD, which is essential to optimise PA interventions and ensure patient safety.

Interventions for promoting physical activity in people with chronic obstructive pulmonary disease (COPD)

BACKGROUND

Escalating awareness of the magnitude of the challenge posed by low levels of physical activity in people with chronic obstructive pulmonary disease (COPD) highlights the need for interventions to increase physical activity participation. The widely-accepted benefits of physical activity, coupled with the increasing availability of wearable monitoring devices to objectively measure participation, has led to a dramatic rise in the number and variety of studies that aimed to improve the physical activity of people with COPD. However, little was known about the relative efficacy of interventions tested so far.

OBJECTIVES

In people with COPD, which interventions are effective at improving objectively-assessed physical activity?

SEARCH METHODS

We identified trials from the Cochrane Airways Trials Register Register, which contains records identified from bibliographic databases including the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, CINAHL, AMED, and PsycINFO. We also searched PEDro, ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform portal and the Australian New Zealand Clinical Trials Registry (from inception to June 2019). We checked reference lists of all primary studies and review articles for additional references, as well as respiratory journals and respiratory meeting abstracts, to identify relevant studies.

SELECTION CRITERIA

We included randomised controlled trials of interventions that used objective measures for the assessment of physical activity in people with COPD. Trials compared an intervention with no intervention or a sham/placebo intervention, an intervention in addition to another standard intervention common to both groups, or two different interventions.

DATA COLLECTION AND ANALYSIS

We used standard methods recommended by Cochrane. Subgroup analyses were possible for supervised compared to unsupervised pulmonary rehabilitation programmes in clinically-stable COPD for a range of physical activity outcomes. Secondary outcomes were health-related quality of life, exercise capacity, adverse events and adherence. Insufficient data were available to perform prespecified subgroup analyses by duration of intervention or disease severity. We undertook sensitivity analyses by removing studies that were at high or unclear risk of bias for the domains of blinding and incomplete outcome data.

MAIN RESULTS

We included 76 studies with 8018 participants. Most studies were funded by government bodies, although some were sponsored by equipment or drug manufacturers. Only 38 studies had physical activity as a primary outcome. A diverse range of interventions have been assessed, primarily in single studies, but improvements have not been systematically demonstrated following any particular interventions. Where improvements were demonstrated, results were confined to single studies, or data for maintained improvement were not provided. Step count was the most frequently reported outcome, but it was commonly assessed using devices with documented inaccuracy for this variable. Compared to no intervention, the mean difference (MD) in time in moderate- to vigorous-intensity physical activity (MVPA) following pulmonary rehabilitation was four minutes per day (95% confidence interval (CI) -2 to 9; 3 studies, 190 participants; low-certainty evidence). An improvement was demonstrated following high-intensity interval exercise training (6 minutes per day, 95% CI 4 to 8; 2 studies, 275 participants; moderate-certainty evidence). One study demonstrated an improvement following six months of physical activity counselling (MD 11 minutes per day, 95% CI 7 to 15; 1 study, 280 participants; moderate-certainty evidence), but we found mixed results for the addition of physical activity counselling to pulmonary rehabilitation. There was an improvement following three to four weeks of pharmacological treatment with long-acting muscarinic antagonist and long-acting beta2-agonist (LAMA/LABA) compared to placebo (MD 10 minutes per day, 95% CI 4 to 15; 2 studies, 423 participants; high-certainty evidence). These interventions also demonstrated improvements in other measures of physical activity. Other interventions included self-management strategies, nutritional supplementation, supplemental oxygen, endobronchial valve surgery, non-invasive ventilation, neuromuscular electrical stimulation and inspiratory muscle training.

AUTHORS' CONCLUSIONS

A diverse range of interventions have been assessed, primarily in single studies. Improvements in physical activity have not been systematically demonstrated following any particular intervention. There was limited evidence for improvement in physical activity with strategies including exercise training, physical activity counselling and pharmacological management. The optimal timing, components, duration and models for interventions are still unclear. Assessment of quality was limited by a lack of methodological detail. There was scant evidence for a continued effect over time following completion of interventions, a likely requirement for meaningful health benefits for people with COPD.

A randomized controlled trial on inspiratory muscle training in pulmonary hypertension: Effects on respiratory functions, functional exercise capacity, physical activity, and quality of life

BACKGROUND

Impaired respiratory muscle function may be one of the causes of increased dyspnea, reduced exercise capacity, and physical activity (PA), and poor quality of life in pulmonary hypertension (PH).

OBJECTIVE

To investigate the effects of threshold inspiratory muscle training (TIMT) on respiratory functions, functional exercise capacity, PA, and QoL in patients with PH.

METHODS

Thirty patients with PH were randomly allocated to a TIMT (n = 15) and sham group (n = 15). Three patients in the sham group could not participate in the program. The TIMT group (n = 15) trained at 30% of the maximal inspiratory pressure (MIP), and the sham group (n = 12) performed at lowest pressure without change in threshold pressure. In both groups, patients performed TIMT at home for 15 min, twice per day, with the MIP load determined by the trainer, and were supervised once weekly at the hospital for eight weeks. The primary outcomes were MIP and maximal expiratory pressure (MEP). The secondary outcome measures included spirometric measurements, six-minute walking distance (6MWD), PA (SenseWear armband and International Physical Activity Questionnaire-Short Form-IPAQ-Short Form), and QoL (Minnesota Living with Heart Failure-MLHF).

RESULTS

After the training, changes in MIP (p = 0.023) were higher in the intervention group compared with the sham group. Differences in MEP, FEV1 (%), FVC (%), FEV1/FVC (%), 6MWD, %6MWD, IPAQ-SF, MLHFQ, and armband parameters were not significantly different between the groups (p > 0.05).

CONCLUSIONS

The results of the study demonstrated that TIMT could increase MIP and did not improve other parameters of respiratory functions, functional exercise capacity, PA, and QoL in patients with PH.

Exercise and Cystic Fibrosis

Cystic fibrosis (CF) is an autosomal recessive, inherited congenital disease caused by the mutation of the family autosomal CF gene, with cumulative exocrine secretion characterized by inflammation, tracheal remodeling, and mucus accumulation. With the development of modern medical technology, CF patients are living longer lives and receiving more and more treatments, including traditional drugs, physical therapy, and gene therapy. Exercise is widely used to prevent and treat metabolic diseases such as cardiovascular diseases, obesity, diabetes, and metabolic syndrome. Regular exercise is beneficial to aerobic capacity and lung health. Exercise therapy has been of great interest since people realized that CF can be affected by exercise. Exercise alone can be used as an ACT (airway clearance technique), which promotes the removal of mucosal cilia. Exercise therapy is more easily accepted by any society, which helps to normalize the lives of CF patients, rather than placing a psychological burden on them. In this chapter, we will review the latest research progress about exercise in CF.

Validity and Reliability of Accelerometers in Patients With COPD: A SYSTEMATIC REVIEW

PURPOSE

Reduced physical activity is associated with poor prognosis in chronic obstructive pulmonary disease (COPD). Accelerometers have greatly improved quantification of physical activity by providing information on step counts, body positions, energy expenditure, and magnitude of force. The purpose of this systematic review was to compare the validity and reliability of accelerometers used in patients with COPD.

METHODS

An electronic database search of MEDLINE and CINAHL was performed. Study quality was assessed with the Strengthening the Reporting of Observational Studies in Epidemiology checklist while methodological quality was assessed using the modified Quality Appraisal Tool for Reliability Studies.

RESULTS

The search yielded 5392 studies; 25 met inclusion criteria. The SenseWear Pro armband reported high criterion validity under controlled conditions (r = 0.75-0.93) and high reliability (ICC = 0.84-0.86) for step counts. The DynaPort MiniMod demonstrated highest concurrent validity for step count using both video and manual methods.

DISCUSSION

Validity of the SenseWear Pro armband varied between studies especially in free-living conditions, slower walking speeds, and with addition of weights during gait. A high degree of variability was found in the outcomes used and statistical analyses performed between studies, indicating a need for further studies to measure reliability and validity of accelerometers in COPD.

CONCLUSION

The SenseWear Pro armband is the most commonly used accelerometer in COPD, but measurement properties are limited by gait speed variability and assistive device use. DynaPort MiniMod and Stepwatch accelerometers demonstrated high validity in patients with COPD but lack reliability data.

Physical activity in incident patients with pulmonary arterial and chronic thromboembolic hypertension

INTRODUCTION

The cardinal symptom of pulmonary hypertension (PH) is dyspnea on exertion, leading to decreased activity in daily living. The aim of this study was to analyze daily physical activity in incident patients with arterial or chronic thromboembolic PH (PAH/CTEPH) and to investigate its correlation with pulmonary hemodynamics, symptoms, exercise capacity, and other outcomes.

METHODS

Incident patients with PAH/CTEPH had a 1-week activity assessment by the arm-worn accelerometer SenseWear within - 3 months/+ 2 weeks of the diagnostic right heart catheterization (RHC) and baseline assessments including 6-minute walking distance (6MWD). Activity was correlated to RHC data at rest and exercise and to other outcomes.

RESULTS

Thirty-nine PH-patients (24 PAH, 15 CTEPH, 23 females, 65(54;73) years, mean pulmonary artery pressure (mPAP) 38(30;46) mmHg, cardiac output (CO) 5.2(4.6;6.3) l/min, 6MWD 458(300;593) m) were included. 64% had a sedentary lifestyle ( < 5000 steps/day), 26% were moderately active (5000-9999 steps/day), and 10% were active. In a multivariate stepwise regression analysis including age, gender, 6MWD and hemodynamics at rest and during exercise (heart rate, mPAP, stroke volume), the 6MWD was the only independent predictor of steps/day (B = 16.8 (95% CI 11.6-22.0), p < 0.001).

CONCLUSION

Daily physical activity as steps/day assessed in incident patients with PAH/CTEPH did not well correlate with invasive hemodynamics at rest or during exercise, but very well with the 6MWD. Whether daily activity assessments provide additional information to simple walk distance on risk factor profiles during follow-up in patients with PAH/CTEPH remains to be clarified.

Counting Steps: A New Way to Monitor Patients with Pulmonary Arterial Hypertension

RATIONALE

Activity levels in patients with pulmonary arterial hypertension (PAH) have correlated with surrogate markers of disease severity. It is not known whether physical activity measures are useful in monitoring patients with PAH.

OBJECTIVES

This pilot study aimed to evaluate whether change in physical activity measured by an accelerometer correlates with changes in six-minute walk distance (6MWD), echocardiographic parameters, NT-proBNP, or health-related quality-of-life measures (HRQOL).

METHODS

The study design was a prospective, observational study in subjects with prevalent PAH. Subjects wore a wrist-worn accelerometer (Fitbit Charge HR®) between two outpatient visits. Daily step count and activity levels were recorded, and the change over time was correlated with changes in 6MWD, echocardiographic parameters, HRQOL, and NT-proBNP.

MEASUREMENTS AND MAIN RESULTS

30 subjects were enrolled, of which 20 patients had adequate accelerometer data to be analyzed over the study duration. The mean duration of follow-up was 136.4 ( ± 47.3) days. The change in daily step count correlated with a change in 6MWD (r 0.43, p 0.05). Changes in duration spent in moderately active (r 0.52, p 0.02), lightly active (r 0.48, p 0.05), and sedentary activity levels (r - 0.54, p 0.02) correlated with a change in HRQOL. Changes in activity levels did not correlate with echocardiographic measures or NT-pro BNP.

CONCLUSIONS

Changes in daily step count and time spent at fairly active, lightly active, and sedentary activity levels correlate with changes in 6MWD, and HRQOL in subjects with PAH suggesting that accelerometry may be a useful monitoring tool.

The feasibility of early pulmonary rehabilitation and activity after COPD exacerbations: external pilot randomised controlled trial, qualitative case study and exploratory economic evaluation

BACKGROUND

Chronic obstructive pulmonary disease (COPD) affects > 3 million people in the UK. Acute exacerbations of COPD (AECOPD) are the second most common reason for emergency hospital admission in the UK. Pulmonary rehabilitation is usual care for stable COPD but there is little evidence for early pulmonary rehabilitation (EPR) following AECOPD, either in hospital or immediately post discharge.

OBJECTIVE

To assess the feasibility of recruiting patients, collecting data and delivering EPR to patients with AECOPD to evaluate EPR compared with usual care.

DESIGN

Parallel-group, pilot 2 × 2 factorial randomised trial with nested qualitative research and an economic analysis.

SETTING

Two acute hospital NHS trusts. Recruitment was carried out from September 2015 to April 2016 and follow-up was completed in July 2016.

PARTICIPANTS

Eligible patients were those aged ≥ 35 years who were admitted with AECOPD, who were non-acidotic and who maintained their blood oxygen saturation level (SpO₂) within a prescribed range. Exclusions included the presence of comorbidities that affected the ability to undertake the interventions.

INTERVENTIONS

(1) Hospital EPR: muscle training delivered at the patient's hospital bed using a cycle ergometer and (2) home EPR: a pulmonary rehabilitation programme delivered in the patient's home. Both interventions were delivered by trained physiotherapists. Participants were allocated on a 1 : 1 : 1 : 1 ratio to (1) hospital EPR (n = 14), (2) home EPR (n = 15), (3) hospital EPR and home EPR (n = 14) and (4) control (n = 15). Outcome assessors were blind to treatment allocation; it was not possible to blind patients.

MAIN OUTCOME MEASURES

Feasibility of recruiting 76 participants in 7 months at two centres; intervention delivery; views on intervention/research acceptability; clinical outcomes including the 6-minute walk distance (6WMD); and costs. Semistructured interviews with participants (n = 27) and research health professionals (n = 11), optimisation assessments and an economic analysis were also undertaken.

RESULTS

Over 7 months 449 patients were screened, of whom most were not eligible for the trial or felt too ill/declined entry. In total, 58 participants (76%) of the target 76 participants were recruited to the trial. The primary clinical outcome (6MWD) was difficult to collect (hospital EPR, n = 5; home EPR, n = 6; hospital EPR and home EPR, n = 5; control, n = 5). Hospital EPR was difficult to deliver over 5 days because of patient discharge/staff availability, with 34.1% of the scheduled sessions delivered compared with 78.3% of the home EPR sessions. Serious adverse events were experienced by 26 participants (45%), none of which was related to the interventions. Interviewed participants generally found both interventions to be acceptable. Home EPR had a higher rate of acceptability, mainly because patients felt too unwell when in hospital to undergo hospital EPR. Physiotherapists generally found the interventions to be acceptable and valued them but found delivery difficult because of staffing issues. The health economic analysis results suggest that there would be value in conducting a larger trial to assess the cost-effectiveness of the hospital EPR and hospital EPR plus home EPR trial arms and collect more information to inform the hospital cost and quality-adjusted life-year parameters, which were shown to be key drivers of the model.

CONCLUSIONS

A full-scale randomised controlled trial using this protocol would not be feasible. Recruitment and delivery of the hospital EPR intervention was difficult. The data obtained can be used to design a full-scale trial of home EPR. Because of the small sample and large confidence intervals, this study should not be used to inform clinical practice.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN18634494.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 11. See the NIHR Journals Library website for further project information.

Activity monitors in pulmonary disease

Physical activity is reduced in patients with chronic pulmonary diseases. Activity monitors can measure physical activity objectively and accurately over prolonged periods of time. Research grade and commercially available devices, using accelerometer technology, are being increasingly used in clinical studies. Physical activity levels have been found to have a moderate to strong correlation with important measures such as pulmonary function, exercise capacity, quality of life, and mortality and hospitalizations in patients with COPD, interstitial lung disease, pulmonary arterial hypertension and cystic fibrosis. Their use as a clinical trial end-point and as a tool to augment rehabilitation efforts has also been explored in patients with COPD with variable results. Due to the ease of use, economic viability, widespread availability and good patient compliance, their use in adult and pediatric medicine is expanding. This narrative review summarizes the current evidence of use of activity monitors in COPD, interstitial lung disease, asthma, pulmonary arterial hypertension, cystic fibrosis and lung transplant patients for the purposes of prognostication, monitoring, outcome measures and intervention.

Physical Activity Monitoring in Patients with Neurological Disorders: A Review of Novel Body-Worn Devices

Aim

The aim was to conduct a systematic review to examine the literature reporting the validity and reliability of wearable physical activity monitoring in individuals with neurological disorders.

Method

A systematic search of the literature was performed using a specific search strategy in PubMed and CINAHL. A search constraint of articles published in English, including human participants, published between January 2008 and March 2017 was applied. Peer-reviewed studies which enrolled adult participants with any neurological disorder were included. For the studies which sought to explore the validity of activity monitors, the outcomes measured using the monitor were compared to a criterion measure of physical activity. The studies' methodological quality was assessed using an adapted version of the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) framework. Data extracted from each study included the following: characteristics of the study participants, study setting, devices used, study protocol/methods, outcomes measured, and the validity/reliability of measurement produced.

Results

Twenty-three studies examining the validity and reliability of 16 different monitors were included. The identified studies comprised participants with a range of different disorders of neurological origin. The available evidence suggests that biaxial or triaxial accelerometer devices positioned around the ankle produce the most accurate step count measurements in patients with neurological disorders. The findings regarding the reliability and validity of activity counts and energy expenditure are largely inconclusive in this population.

Discussion

Ankle-worn biaxial or triaxial accelerometer-type devices provide the most accurate measurement of physical activity. However, further work is required in this field before wearable activity monitoring can be more widely implemented clinically. Standardised activity monitoring protocols are required for implementing these devices in clinical trials and clinical practice, and consensus is required as to the reporting and interpretation of derived variables.

Elosulfase alfa (BMN 110) for the treatment of mucopolysaccharidosis IVA (Morquio A Syndrome)

INTRODUCTION

Morquio A syndrome is a rare, autosomal recessive, lysosomal storage disorder caused by a deficiency in the enzyme N-acetylgalactosamine-6-sulfatase (GALNS). In 2014, the use of recombinant human GALNS, elosulfase alfa, was approved in the European Union, Canada, the United States, Australia, and Brazil for the treatment of Morquio A syndrome. Elosulfase alfa is administered intravenously once-weekly at a dose of 2.0 mg/kg. Areas covered: This is a review of the efficacy, safety and tolerability, pharmacokinetics and pharmacodynamics, and other outcomes of elosulfase alfa treatment of patients with Morquio A. A discussion of other treatment considerations, limitations, and future directions in the use of elosulfase alfa is provided. Expert commentary: Pharmacokinetic studies outside of clinical trials and in 'real-world' clinical settings need to be performed. We cannot currently predict which patient is going to respond well to enzyme replacement therapy; thus, all patients should be given the option to receive treatment for at least 12 months. Additionally, accurate biomarkers for evaluating disease state and drug responsiveness would greatly aid in the treatment of patients with Morquio A. In addition, improved and innovative daily lifestyle measures are greatly needed to adequately measure clinical response and true impact on quality of life.

The role of an activity monitor in the objective evaluation of patients with pulmonary hypertension

INTRODUCTION

Patients with pulmonary hypertension (PH) show no symptoms at rest, but symptoms are triggered by physical activities.

OBJECTIVES

The primary aim of our study was to assess physical activity of patients with PH by using an activity monitor. The secondary aim was to evaluate the correlation between the activity monitor parameters and 6-min walk distance (6MWD), activity of daily living (ADL), quality of life, WHO functional class and PH classification.

METHODS

Thirty-eight patients with pulmonary arterial hypertension (PAH) and seven patients with chronic thromboembolic PH were included in the study. Physical activity was assessed using a SenseWear arm band. A 6-min walk test was performed. Daily living activities were assessed using the 'nottingham extended activity of daily living index' (NEADL). For quality of life assessments, 'Minnesota living with heart failure' (MLHF) and 'Short form-36' (SF-36) surveys were used.

RESULTS

Physical activity, exercise capacity, quality of life and contribution to ADL were lower in patients with PH. These data were associated with the 6MWD, quality of life and ADL index scores. We also found weak and moderate correlations between activity monitor data and SF-36 sub-group scores, MLHF and NEADL scores (P < 0.05). For the group with PAH, idiopathic PAH patients had more exercise capacity and total energy expenditure compared with patients with scleroderma-associated PAH.

CONCLUSION

Correlation between activity monitor data and 6MWD, most of SF-36 sub-group scores, MLHF scores and NEADL index scores suggest that activity monitor can be used in the evaluation of patients with PH.