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International Journal of Clinical... Oct 2021To identify, systematically evaluate and summarise the best available evidence on the frequency of long COVID-19 (post-acute COVID-19 syndrome), its clinical... (Review)
Review
AIMS
To identify, systematically evaluate and summarise the best available evidence on the frequency of long COVID-19 (post-acute COVID-19 syndrome), its clinical manifestations, and the criteria used for diagnosis.
METHODS
Systematic review conducted with a comprehensive search including formal databases, COVID-19 or SARS-CoV-2 data sources, grey literature, and manual search. We considered for inclusion clinical trials, observational longitudinal comparative and non-comparative studies, cross-sectional, before-and-after, and case series. We assessed the methodological quality by specific tools based on the study designs. We presented the results as a narrative synthesis regarding the frequency and duration of long COVID-19, signs and symptoms, criteria used for diagnosis, and potential risk factors.
RESULTS
We included 25 observational studies with moderate to high methodological quality, considering 5440 participants. The frequency of long COVID-19 ranged from 4.7% to 80%, and the most prevalent signs/symptoms were chest pain (up to 89%), fatigue (up to 65%), dyspnea (up to 61%), and cough and sputum production (up to 59%). Temporal criteria used to define long COVID-19 varied from 3 to 24 weeks after acute phase or hospital discharge. Potentially associated risk factors were old age, female sex, severe clinical status, a high number of comorbidities, hospital admission, and oxygen supplementation at the acute phase. However, limitations related to study designs added uncertainty to this finding. None of the studies assessed the duration of signs/symptoms.
CONCLUSION
The frequency of long COVID-19 reached up to 80% over the studies included and occurred between 3 and 24 weeks after acute phase or hospital discharge. Chest pain, fatigue, dyspnea, and cough were the most reported clinical manifestations attributed to the condition. Based on these systematic review findings, there is an urgent need to understand this emerging, complex and challenging medical condition. Proposals for diagnostic criteria and standard terminology are welcome.
Topics: COVID-19; Cross-Sectional Studies; Dyspnea; Female; Humans; SARS-CoV-2; Post-Acute COVID-19 Syndrome
PubMed: 33977626
DOI: 10.1111/ijcp.14357 -
Forschende Komplementarmedizin (2006) 2015The aim of this review was to systematically assess the literature on herbal medicine for cough as a symptom of upper respiratory tract infections and common cold. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The aim of this review was to systematically assess the literature on herbal medicine for cough as a symptom of upper respiratory tract infections and common cold.
METHODS
The Cochrane Library, Scopus, MEDLINE/PubMed, and Embase were searched through March 2012 for RCTs testing the effects of herbal medicine for cough. Risk of bias was assessed using the Cochrane tool.
RESULTS
34 RCTs (N = 7,083) on Pelargonium sidoides (11 RCTs), Echinacea (8 RCTs), Andrographis paniculata (6 RCTs), ivy/primrose/thyme (4 RCTs), essential oils (4 RCTs) and bakumondoto (1 RCT) were included. Controls were mainly placebo. Most studies had a low risk of bias. The meta-analysis revealed strong evidence for A. paniculata (SMD = -1.00, 95% CI = -1.85, -0.15; P<0.001) and ivy/primrose/thyme (RR = 1.40, 95% CI = 1.23, 1.60; P<0.001) in treating cough; moderate evidence for P. sidiodes (RR = 4.60; 95% CI = 2.89,7.31; P<0.001), and limited evidence for Echinacea (SMD = -0.68; 95% CI = -1.32, -0.04; P = 0.04).
CONCLUSION
This review found strong evidence for A. paniculata and ivy/primrose/thyme-based preparations and moderate evidence for P. sidoides being significantly superior to placebo in alleviating the frequency and severity of patients' cough symptoms. Additional research, including other herbal treatments, is needed in this area.
Topics: Cough; Herbal Medicine; Plant Extracts; Respiratory Tract Infections; Treatment Outcome
PubMed: 26840418
DOI: 10.1159/000442111 -
Sleep Medicine Reviews Dec 2021Obstructive Sleep Apnea (OSA) is often treated with Mandibular Advancement Devices (MADs). It is unclear whether particular design features are superior to others in... (Meta-Analysis)
Meta-Analysis Review
Obstructive Sleep Apnea (OSA) is often treated with Mandibular Advancement Devices (MADs). It is unclear whether particular design features are superior to others in terms of OSA alleviation. In order to facilitate clinical decision-making, this systematic review summarizes the objective and subjective outcomes of different available MAD designs. Studies comparing different MAD designs in OSA treatment were searched. After screening 1887 titles and abstracts, 20 original RCTs and six cohort studies were included. 14 articles were systematically reviewed in a meta-analysis. The decrease in AHI was significantly different between some of the MAD designs. The clinical relevance of the observed differences was however limited. Monoblock appliances performed more favorable, compared to bilateral thrust (effect size:-0.37; CI:-1.81 to 0.07). Midline traction appliances performed more favorable, compared to other designs. Custom appliances performed more favorable, compared to thermoplastic appliances (effect size:0.86; CI:-0.62 to 2.35). Furthermore, there were no clinically relevant differences between MAD designs in reduction of ESS, compliance, preference, side effects, and cost effectiveness. With respect to the included trials, presently there is not one superior custom MAD design in OSA treatment regarding the effect on AHI reduction, ESS improvement, compliance, preference, side effects, cost effectiveness, and other disease-related outcomes. We confirm custom MAD designs perform superior to thermoplastic MAD designs.
Topics: Continuous Positive Airway Pressure; Humans; Mandibular Advancement; Occlusal Splints; Sleep Apnea, Obstructive; Treatment Outcome
PubMed: 34662769
DOI: 10.1016/j.smrv.2021.101557 -
Chest Dec 2020The recent pandemic highlights the essential nature of optimizing the use of invasive mechanical ventilation (IMV) in complex critical care settings. This review of...
BACKGROUND
The recent pandemic highlights the essential nature of optimizing the use of invasive mechanical ventilation (IMV) in complex critical care settings. This review of reviews maps evidence-based practices (EBPs) that are associated with better outcomes among adult patients with acute respiratory failure or ARDS on the continuum of care, from intubation to liberation.
RESEARCH QUESTION
What EPBs are recommended to reduce the duration of IMV and mortality rate among patients with acute respiratory failure/ARDS?
STUDY DESIGN AND METHODS
We identified an initial set of reports that links EBPs to mortality rates and/or duration of IMV. We conducted a review of reviews, focusing on preappraised guidelines, meta-analyses, and systematic reviews. We searched Scopus, CINAHL, and PubMed from January 2016 to January 2019 for additional evidence that has not yet been incorporated into current guidelines.
RESULTS
Our initial search produced 61 publications that contained 42 EBPs. We excluded 42 manuscripts during the data extraction process, primarily because they were not associated with improved patient outcomes. The remaining 19 preappraised guidelines, meta-analyses, and systematic reviews met our full inclusion criteria and spanned the continuum of IMV care from intubation to liberation. These contained 20 EBPs, a majority of which were supported with moderate levels of evidence. Of these, six EBPs focused on intubation and escalation of care, such as ventilator management and synchrony; ten EBPs reduced complications associated with IMV, which included spontaneous awakening and breathing trials and early mobility protocols; and four EBPs promoted timely extubation and postextubation recovery.
INTERPRETATION
This review describes EBPs that are associated with fewer ventilator days and/or lower mortality rates among patients who received IMV for acute respiratory failure/ARDS. Many of these EBPs are connected across the care continuum, which indicates the need to promote and assess effective implementation jointly, rather than individually.
Topics: Critical Pathways; Duration of Therapy; Evidence-Based Practice; Humans; Respiration, Artificial; Respiratory Distress Syndrome; Respiratory Insufficiency; Survival Analysis
PubMed: 32682771
DOI: 10.1016/j.chest.2020.06.080 -
Chest Jan 2018We performed systematic reviews using the population, intervention, comparison, outcome (PICO) format to answer the following key clinical question: Are the CHEST 2006...
BACKGROUND
We performed systematic reviews using the population, intervention, comparison, outcome (PICO) format to answer the following key clinical question: Are the CHEST 2006 classifications of acute, subacute and chronic cough and associated management algorithms in adults that were based on durations of cough useful?
METHODS
We used the CHEST Expert Cough Panel's protocol for the systematic reviews and the American College of Chest Physicians (CHEST) methodological guidelines and Grading of Recommendations Assessment, Development, and Evaluation framework. Data from the systematic reviews in conjunction with patient values and preferences and the clinical context were used to form recommendations or suggestions. Delphi methodology was used to obtain the final grading.
RESULTS
With respect to acute cough (< 3 weeks), only three studies met our criteria for quality assessment, and all had a high risk of bias. As predicted by the 2006 CHEST Cough Guidelines, the most common causes were respiratory infections, most likely of viral cause, followed by exacerbations of underlying diseases such as asthma and COPD and pneumonia. The subjects resided on three continents: North America, Europe, and Asia. With respect to subacute cough (duration, 3-8 weeks), only two studies met our criteria for quality assessment, and both had a high risk of bias. As predicted by the 2006 guidelines, the most common causes were postinfectious cough and exacerbation of underlying diseases such as asthma, COPD, and upper airway cough syndrome (UACS). The subjects resided in countries in Asia. With respect to chronic cough (> 8 weeks), 11 studies met our criteria for quality assessment, and all had a high risk of bias. As predicted by the 2006 guidelines, the most common causes were UACS from rhinosinus conditions, asthma, gastroesophageal reflux disease, nonasthmatic eosinophilic bronchitis, combinations of these four conditions, and, less commonly, a variety of miscellaneous conditions and atopic cough in Asian countries. The subjects resided on four continents: North America, South America, Europe, and Asia.
CONCLUSIONS
Although the quality of evidence was low, the published literature since 2006 suggests that CHEST's 2006 Cough Guidelines and management algorithms for acute, subacute, and chronic cough in adults appeared useful in diagnosing and treating patients with cough around the globe. These same algorithms have been updated to reflect the advances in cough management as of 2017.
Topics: Acute Disease; Adult; Algorithms; Asthma; Chronic Disease; Consensus; Cough; Humans; Practice Guidelines as Topic; Pulmonary Disease, Chronic Obstructive; Respiratory Tract Infections
PubMed: 29080708
DOI: 10.1016/j.chest.2017.10.016 -
Respirology (Carlton, Vic.) Jan 2022Despite the challenges of diagnosing and managing adult patients with chronic cough, a systematic synthesis of evidence on aetiological risk factor is lacking. We... (Meta-Analysis)
Meta-Analysis Review
Despite the challenges of diagnosing and managing adult patients with chronic cough, a systematic synthesis of evidence on aetiological risk factor is lacking. We systematically searched PubMed and EMBASE to synthesize the current evidence for longitudinal associations between a wide range of risk factors and chronic cough in the general adult population, following the meta-analysis of observational studies in epidemiology (MOOSE) guidelines. The Newcastle-Ottawa scale was used to assess the quality of the included studies. Fixed-effect meta-analysis was conducted where appropriate. Of 26 eligible articles, 16 domains of risk factors were assessed. There was consistent evidence that asthma (pooled adjusted OR [aOR] = 3.01; 95% CI: 2.33-3.70; I = 0%; number of articles [N] = 3) and low education levels/socioeconomic status (SES) (pooled aOR = 1.46; 95% CI: 1.20-1.72; I = 0%; N = 3) were associated with an increased risk of chronic cough after adjusting for smoking and other confounders. While continuous smoking was associated with chronic cough (aOR = 1.81; 95% CI: 1.36-2.26; I = 57%; N = 3), there was too little evidence to draw conclusions for occupational exposures, outdoor air pollution, early-life exposures, diet, snoring and other chronic conditions, including obesity, chronic obstructive pulmonary disease, gastro-oesophageal reflux disease and chronic pain. Asthma, persistent smoking and lower education/SES were associated with an increased risk of chronic cough. Longitudinal associations between other factors frequently mentioned empirically (i.e., occupational exposures, air pollution and chronic respiratory conditions) need further investigation, ideally with objective and standardized measurement.
Topics: Air Pollution; Chronic Disease; Cough; Humans; Pulmonary Disease, Chronic Obstructive; Risk Factors
PubMed: 34658107
DOI: 10.1111/resp.14169 -
The Lancet. Respiratory Medicine Jun 2022Awake prone positioning has been broadly utilised for non-intubated patients with COVID-19-related acute hypoxaemic respiratory failure, but the results from published... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Awake prone positioning has been broadly utilised for non-intubated patients with COVID-19-related acute hypoxaemic respiratory failure, but the results from published randomised controlled trials (RCTs) in the past year are contradictory. We aimed to systematically synthesise the outcomes associated with awake prone positioning, and evaluate these outcomes in relevant subpopulations.
METHODS
In this systematic review and meta-analysis, two independent groups of researchers searched MEDLINE, Embase, PubMed, Web of Science, Scopus, MedRxiv, BioRxiv, and ClinicalTrials.gov for RCTs and observational studies (with a control group) of awake prone positioning in patients with COVID-19-related acute hypoxaemic respiratory failure published in English from Jan 1, 2020, to Nov 8, 2021. We excluded trials that included patients intubated before or at enrolment, paediatric patients (ie, younger than 18 years), or trials that did not include the supine position in the control group. The same two independent groups screened studies, extracted the summary data from published reports, and assessed the risk of bias. We used a random-effects meta-analysis to pool individual studies. We used the Grading of Recommendations Assessment, Development, and Evaluation approach to assess the certainty and quality of the evidence. The primary outcome was the reported cumulative intubation risk across RCTs, and effect estimates were calculated as risk ratios (RR;95% CI). The analysis was primarily conducted on RCTs, and observational studies were used for sensitivity analyses. No serious adverse events associated with awake prone positioning were reported. The study protocol was prospectively registered with PROSPERO, CRD42021271285.
FINDINGS
A total of 1243 studies were identified, we assessed 138 full-text articles and received the aggregated results of three unpublished RCTs; therefore, after exclusions, 29 studies were included in the study. Ten were RCTs (1985 patients) and 19 were observational studies (2669 patients). In ten RCTs, awake prone positioning compared with the supine position significantly reduced the need for intubation in the overall population (RR 0·84 [95% CI 0·72-0·97]). A reduced need for intubation was shown among patients who received advanced respiratory support (ie, high-flow nasal cannula or non-invasive ventilation) at enrolment (RR 0·83 [0·71-0·97]) and in intensive care unit (ICU) settings (RR 0·83 [0·71-0·97]) but not in patients receiving conventional oxygen therapy (RR 0·87 [0·45-1·69]) or in non-ICU settings (RR 0·88 [0·44-1·76]). No obvious risk of bias and publication bias was found among the included RCTs for the primary outcome.
INTERPRETATION
In patients with COVID-19-related acute hypoxaemic respiratory failure, awake prone positioning reduced the need for intubation, particularly among those requiring advanced respiratory support and those in ICU settings. Awake prone positioning should be used in patients who have acute hypoxaemic respiratory failure due to COVID-19 and require advanced respiratory support or are treated in the ICU.
FUNDING
OpenAI, Rice Foundation, National Institute for Health Research, and Oxford Biomedical Research Centre.
Topics: COVID-19; Child; Humans; Patient Positioning; Prone Position; Respiratory Insufficiency; Wakefulness
PubMed: 35305308
DOI: 10.1016/S2213-2600(22)00043-1 -
PloS One 2020This systematic review and meta-analysis examines the associations of allergic rhinitis with sleep duration and sleep impairment. Observational studies published before... (Meta-Analysis)
Meta-Analysis
This systematic review and meta-analysis examines the associations of allergic rhinitis with sleep duration and sleep impairment. Observational studies published before August 2019 were obtained through English language literature searches in the PubMed, Embase, and CINAHL databases. Mean differences and odds ratios with 95% confidence intervals were extracted and used for meta-analysis. Heterogeneity was confirmed by the I2-heterogeneity test. Subgroup analysis was conducted to evaluate the influence of study design. The Grading of Recommendations Assessment, Development, and Evaluation approach was used to determine the level of evidence. In total, 2544 records were identified through database searches; 914 duplicate records were excluded, 1452 records were removed after screening of titles and abstracts, 151 records were excluded after full-text screening, and 27 articles were included in the final meta-analyses. A total of 240,706,026 patients (19,444,043 with allergic rhinitis) were considered. No significant difference in sleep duration between the allergic rhinitis and the control groups was found. Patients with allergic rhinitis presented with significantly higher sleep quality scores, sleep disturbances scores, and sleep latency scores; more frequent use of sleep medications; and lower sleep efficiency as measured by the Pittsburgh Sleep Quality Index and polysomnography. Meta-analyses for adjusted odds ratios showed that allergic rhinitis was also associated with higher risks of nocturnal dysfunctions, including insomnia, nocturnal enuresis, restless sleep, sleep-disordered breathing, obstructive sleep apnea, and snoring. Meta-analysis for adjusted odds ratio also showed that allergic rhinitis was associated with daytime dysfunction, including difficulty waking up, daytime sleepiness, morning headache, and the use of sleep medications. The overall quality of evidence ranged from low to very low, indicating that caution is required when interpreting these results. This study demonstrates that there is a significant association of AR with sleep characteristics.
Topics: Adolescent; Adult; Aged; Child; Child, Preschool; Humans; Middle Aged; Observational Studies as Topic; Polysomnography; Quality of Life; Rhinitis, Allergic; Sleep; Sleep Apnea Syndromes; Sleep Apnea, Obstructive; Sleep Wake Disorders; Snoring; Young Adult
PubMed: 32053609
DOI: 10.1371/journal.pone.0228533 -
The Cochrane Database of Systematic... Oct 2020Respiratory distress, particularly respiratory distress syndrome (RDS), is the single most important cause of morbidity and mortality in preterm infants. In infants with... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Respiratory distress, particularly respiratory distress syndrome (RDS), is the single most important cause of morbidity and mortality in preterm infants. In infants with progressive respiratory insufficiency, intermittent positive pressure ventilation (IPPV) with surfactant has been the usual treatment, but it is invasive, potentially resulting in airway and lung injury. Continuous positive airway pressure (CPAP) has been used for the prevention and treatment of respiratory distress, as well as for the prevention of apnoea, and in weaning from IPPV. Its use in the treatment of RDS might reduce the need for IPPV and its sequelae.
OBJECTIVES
To determine the effect of continuous distending pressure in the form of CPAP on the need for IPPV and associated morbidity in spontaneously breathing preterm infants with respiratory distress.
SEARCH METHODS
We used the standard strategy of Cochrane Neonatal to search CENTRAL (2020, Issue 6); Ovid MEDLINE and Epub Ahead of Print, In-Process & Other Non-Indexed Citations, Daily and Versions; and CINAHL on 30 June 2020. We also searched clinical trials databases and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.
SELECTION CRITERIA
All randomised or quasi-randomised trials of preterm infants with respiratory distress were eligible. Interventions were CPAP by mask, nasal prong, nasopharyngeal tube or endotracheal tube, compared with spontaneous breathing with supplemental oxygen as necessary.
DATA COLLECTION AND ANALYSIS
We used standard methods of Cochrane and its Neonatal Review Group, including independent assessment of risk of bias and extraction of data by two review authors. We used the GRADE approach to assess the certainty of evidence. Subgroup analyses were planned on the basis of birth weight (greater than or less than 1000 g or 1500 g), gestational age (groups divided at about 28 weeks and 32 weeks), timing of application (early versus late in the course of respiratory distress), pressure applied (high versus low) and trial setting (tertiary compared with non-tertiary hospitals; high income compared with low income) MAIN RESULTS: We included five studies involving 322 infants; two studies used face mask CPAP, two studies used nasal CPAP and one study used endotracheal CPAP and continuing negative pressure for a small number of less ill babies. For this update, we included one new trial. CPAP was associated with lower risk of treatment failure (death or use of assisted ventilation) (typical risk ratio (RR) 0.64, 95% confidence interval (CI) 0.50 to 0.82; typical risk difference (RD) -0.19, 95% CI -0.28 to -0.09; number needed to treat for an additional beneficial outcome (NNTB) 6, 95% CI 4 to 11; I = 50%; 5 studies, 322 infants; very low-certainty evidence), lower use of ventilatory assistance (typical RR 0.72, 95% CI 0.54 to 0.96; typical RD -0.13, 95% CI -0.25 to -0.02; NNTB 8, 95% CI 4 to 50; I = 55%; very low-certainty evidence) and lower overall mortality (typical RR 0.53, 95% CI 0.34 to 0.83; typical RD -0.11, 95% CI -0.18 to -0.04; NNTB 9, 95% CI 2 to 13; I = 0%; 5 studies, 322 infants; moderate-certainty evidence). CPAP was associated with increased risk of pneumothorax (typical RR 2.48, 95% CI 1.16 to 5.30; typical RD 0.09, 95% CI 0.02 to 0.16; number needed to treat for an additional harmful outcome (NNTH) 11, 95% CI 7 to 50; I = 0%; 4 studies, 274 infants; low-certainty evidence). There was no evidence of a difference in bronchopulmonary dysplasia, defined as oxygen dependency at 28 days (RR 1.04, 95% CI 0.35 to 3.13; I = 0%; 2 studies, 209 infants; very low-certainty evidence). The trials did not report use of surfactant, intraventricular haemorrhage, retinopathy of prematurity, necrotising enterocolitis and neurodevelopment outcomes in childhood.
AUTHORS' CONCLUSIONS
In preterm infants with respiratory distress, the application of CPAP is associated with reduced respiratory failure, use of mechanical ventilation and mortality and an increased rate of pneumothorax compared to spontaneous breathing with supplemental oxygen as necessary. Three out of five of these trials were conducted in the 1970s. Therefore, the applicability of these results to current practice is unclear. Further studies in resource-poor settings should be considered and research to determine the most appropriate pressure level needs to be considered.
Topics: Bronchopulmonary Dysplasia; Continuous Positive Airway Pressure; Humans; Infant, Low Birth Weight; Infant, Newborn; Infant, Premature; Intermittent Positive-Pressure Ventilation; Outcome Assessment, Health Care; Pneumothorax; Pulmonary Surfactants; Randomized Controlled Trials as Topic; Respiratory Distress Syndrome, Newborn; Respiratory Insufficiency; Selection Bias; Treatment Failure
PubMed: 33058208
DOI: 10.1002/14651858.CD002271.pub3 -
The Cochrane Database of Systematic... Aug 2021Chronic non-invasive ventilation (NIV) is increasingly being used to treat people with COPD who have respiratory failure, but the evidence supporting this treatment has... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Chronic non-invasive ventilation (NIV) is increasingly being used to treat people with COPD who have respiratory failure, but the evidence supporting this treatment has been conflicting.
OBJECTIVES
To assess the effects of chronic non-invasive ventilation at home via a facial mask in people with COPD, using a pooled analysis of IPD and meta-analysis.
SEARCH METHODS
We searched the Cochrane Airways Register of Trials, MEDLINE, Embase, PsycINFO, CINAHL, AMED, proceedings of respiratory conferences, clinical trial registries and bibliographies of relevant studies. We conducted the latest search on 21 December 2020.
SELECTION CRITERIA
We included randomised controlled trials (RCTs) comparing chronic NIV for at least five hours per night for three consecutive weeks or more (in addition to standard care) versus standard care alone, in people with COPD. Studies investigating people initiated on NIV in a stable phase and studies investigating NIV commenced after a severe COPD exacerbation were eligible, but we reported and analysed them separately. The primary outcomes were arterial blood gases, health-related quality of life (HRQL), exercise capacity (stable COPD) and admission-free survival (post-exacerbation COPD). Secondary outcomes for both populations were: lung function, COPD exacerbations and admissions, and all-cause mortality. For stable COPD, we also reported respiratory muscle strength, dyspnoea and sleep efficiency.
DATA COLLECTION AND ANALYSIS
We used standard methodological procedures expected by Cochrane. After inclusion of a study, we requested the IPD. We analysed continuous and time-to-event data using linear- and cox-regression mixed-effect models with a random effect on study level. We analysed dichotomous IPD using generalised estimating equations. We adjusted all models for age and sex. We assessed changes in outcomes after three and 12 months. We also conducted a meta-analysis on aggregated trial data.
MAIN RESULTS
We included 14 new RCTs in this review update, in addition to the seven previously included. Seventeen studies investigated chronic NIV in stable COPD and four studies investigated chronic NIV commenced after a severe COPD exacerbation. Three studies compared NIV to sham continuous positive airway pressure (2 to 4 cmHO). Seven studies used a nasal mask, one study used an oronasal mask and eight studies used both interfaces. Five studies did not report the interface. The majority of trials (20/21) were at high risk of performance bias due to an unblinded design. We considered 11 studies to have a low risk of selection bias and 13 to have a low risk of attrition bias. We collected and analysed the IPD from 13 stable COPD studies (n = 778, 68% of the participants included) and from three post-exacerbation studies (n = 364, 96% of the participants included). In the stable COPD group, NIV probably results in a minor benefit on the arterial partial pressure of oxygen (PaO) after three months (adjusted mean difference (AMD) 0.27 kPa, 95% CI 0.04 to 0.49; 9 studies, 271 participants; moderate-certainty evidence), but there was little to no benefit at 12 months (AMD 0.09 kPa, 95% CI -0.23 to 0.42; 3 studies, 171 participants; low-certainty evidence). The arterial partial pressure of carbon dioxide (PaCO) was reduced in participants allocated to NIV after three months (AMD -0.61 kPa, 95% CI -0.77 to -0.45; 11 studies, 475 participants; high-certainty evidence) and persisted up to 12 months (AMD -0.42 kPa, 95% CI -0.68 to -0.16; 4 studies, 232 participants; high-certainty evidence). Exercise capacity was measured with the 6-minute walking distance (minimal clinical important difference: 26 m). There was no clinically relevant effect of NIV on exercise capacity (3 months: AMD 15.5 m, 95% CI -0.8 to 31.7; 8 studies, 330 participants; low-certainty evidence; 12 months: AMD 26.4 m, 95% CI -7.6 to 60.5; 3 studies, 134 participants; very low-certainty evidence). HRQL was measured with the Severe Respiratory Insufficiency and the St. Georges's Respiratory Questionnaire and may be improved by NIV, but only after three months (3 months: standardised mean difference (SMD) 0.39, 95% CI 0.15 to 0.62; 5 studies, 259 participants; very low-certainty evidence; 12 months: SMD 0.15, 95% CI -0.13 to 0.43; 4 studies, 200 participants; very low-certainty evidence). Lastly, the risk for all-cause mortality is likely reduced by NIV (adjusted hazard ratio (AHR) 0.75, 95% CI 0.58 to 0.97; 3 studies, 405 participants; moderate-certainty evidence). In the post-exacerbation COPD group, there was little to no benefit on the PaO after three months, but there may be a slight decrease after 12 months (3 months: AMD -0.10 kPa, 95% CI -0.65 to 0.45; 3 studies, 234 participants; low-certainty evidence; 12 months: -0.27 kPa, 95% CI -0.86 to 0.32, 3 studies; 170 participants; low-certainty evidence). The PaCO was reduced by NIV at both three months (AMD -0.40 kPa, 95% CI -0.70 to -0.09; 3 studies, 241 participants; moderate-certainty evidence) and 12 months (AMD -0.52 kPa, 95% CI -0.87 to -0.18; 3 studies, 175 participants; high-certainty evidence). NIV may have little to no benefit on HRQL (3 months: SMD 0.25, 95% CI -0.01 to 0.51; 2 studies, 219 participants; very low-certainty evidence; 12 months: SMD 0.25, 95% -0.06 to 0.55; 2 studies, 164 participants; very low-certainty evidence). Admission-free survival seems improved with NIV (AHR 0.71, 95% CI 0.54 to 0.94; 2 studies, 317 participants; low-certainty evidence), but the risk for all-cause mortality does not seem to improve (AHR 0.97, 95% CI 0.74 to 1.28; 2 studies, 317 participants; low-certainty evidence).
AUTHORS' CONCLUSIONS
Regardless of the timing of initiation, chronic NIV improves daytime hypercapnia. In addition, in stable COPD, survival seems to be improved and there might be a short term HRQL benefit. In people with persistent hypercapnia after a COPD exacerbation, chronic NIV might prolong admission-free survival without a beneficial effect on HRQL. In stable COPD, future RCTs comparing NIV to a control group receiving standard care might no longer be warranted, but research should focus on identifying participant characteristics that would define treatment success. Furthermore, the optimal timing for initiation of NIV after a severe COPD exacerbation is still unknown.
Topics: Disease Progression; Dyspnea; Humans; Noninvasive Ventilation; Pulmonary Disease, Chronic Obstructive; Quality of Life; Respiratory Insufficiency
PubMed: 34368950
DOI: 10.1002/14651858.CD002878.pub3