Impact of lifetime air pollution exposure patterns on the risk of chronic disease.

Long-term exposure to air pollution can lead to cardiovascular disease, metabolic syndrome, and chronic respiratory disease. However, from a lifetime perspective, the critical period of air pollution exposure in terms of health risk is unknown. This study aimed to evaluate the impact of air pollution exposure at different life stages. The study participants were recruited from community centers in Northern Taiwan between October 2018 and April 2021. Their annual averages for fine particulate matter (PM2.5) exposure were derived from a national visibility database. Lifetime PM2.5 exposures were determined using residential address information and were separated into three stages (<20, 20-40, and >40 years). We employed exponentially weighted moving averages, applying different weights to the aforementioned life stages to simulate various weighting distribution patterns. Regression models were implemented to examine associations between weighting distributions and disease risk. We applied a random forest model to compare the relative importance of the three exposure life stages. We also compared model performance by evaluating the accuracy and F1 scores (the harmonic mean of precision and recall) of late-stage (>40 years) and lifetime exposure models. Models with 89% weighting on late-stage exposure showed significant associations between PM2.5 exposure and metabolic syndrome, hypertension, diabetes, and cardiovascular disease, but not gout or osteoarthritis. Lifetime exposure models showed higher precision, accuracy, and F1 scores for metabolic syndrome, hypertension, diabetes, and cardiovascular disease, whereas late-stage models showed lower performance metrics for these outcomes. We conclude that exposure to high-level PM2.5 after 40 years of age may increase the risk of metabolic syndrome, hypertension, diabetes, and cardiovascular disease. However, models considering lifetime exposure showed higher precision, accuracy, and F1 scores and lower equal error rates than models incorporating only late-stage exposures. Future studies regarding long-term air pollution modelling are required considering lifelong exposure pattern. .1.

Exposure to PM2.5 is associated with malignant pleural effusion in lung cancer patients.

Air pollution has been recognized to be a risk factor for lung cancer. The objective of this study was to investigate the effects of air pollution on heavy metal alterations in the pleural effusion of lung cancer patients. Pleural effusion was collected from patients with lung cancer and congestive heart failure (CHF). One-year average levels of particulate matter with an aerodynamic diameter of < 10 µm (PM10), PM2.5, NO2, and SO2 were linked to the exposure of these subjects. Traffic-related metals, included Al, Fe, Cu, Zn, and Pb, were determined in the pleural effusion. Logistic regression models were used to examine their associations. There were 63 lung cancer patients and 31 CHF patients enrolled in the current study. We found that PM10, PM2.5, and NO2 were negatively correlated with Al in the pleural effusion, whereas PM2.5 was positively correlated with Zn in the pleural effusion. Increases in 1 µg/m3 of PM2.5 and 1 ng/mL of Zn were associated with lung cancer (adjusted OR=2.394, 95% CI= 1.446-3.964 for PM2.5; adjusted OR=1.003, 95% CI=1.000-1.005 for Zn). Increases in PM2.5 and Zn in the pleural effusion increased the risk of malignant pleural effusion in lung cancer patients (adjusted OR=1.517; 95% CI=1.082-2.127 for PM2.5; adjusted OR=1.002, 95% CI=1.000-1.005 for Zn). Furthermore, we observed that adenocarcinomas increased in association with a 1-µg/m3 increase in PM2.5 (crude OR=1.683; 95% CI=1.006-2.817) in lung cancer patients. In conclusion, PM2.5 exposure and the possible resultant Zn in the pleural effusion associated with the development of malignant pleural effusion in lung cancer.

Chikungunya infection: First autochthonous cases in Taiwan.

The first autochthonous case and the first outbreak of chikungunya in Taiwan occurred during July-October 2019, with a total of 21 cases confirmed. Genetic analysis revealed the strains belonged to East/Central/South African genotype and had 99.95%-100% identity with the strains from the imported cases from Myanmar in 2019. This event confirmed that the imported chikungunya cases has the potential to cause autochthonous transmission in Taiwan; intensified surveillance and vector control measures are essential to contain the outbreak.

Human Case of Severe Fever with Thrombocytopenia Syndrome Virus Infection, Taiwan, 2019.

We report on a 70-year-old man with fever, leukopenia, thrombocytopenia, vomiting, malaise, dyspnea, and consciousness disturbance who was infected with severe fever with thrombocytopenia syndrome virus in northern Taiwan, 2019. This autochthonous case was confirmed by reverse transcription PCR, virus isolation, and genomic sequencing.

Normal saline instillation before suctioning: A meta-analysis of randomized controlled trials.

BACKGROUND: For airway management of intensive care unit (ICU) patients who are intubated, a 5-10-mL bolus of sterile normal saline (NS) solution is commonly instilled into an endotracheal or tracheostomy tube before suctioning. However, NS instillation has been associated with adverse events such as dyspnea, increasing heart rate, decreasing of oxygenation, blood pressure, and other vital parameters. OBJECTIVE: To conduct a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the necessity of NS instillation before suctioning in ICU patients. DATA SOURCES: The PubMed, Embase, Cochrane Library, and Scopus databases and the ClinicalTrials.gov registry were searched for studies published before May 2016. REVIEW METHODS: RCTs evaluating the outcome of NS instillation before suctioning in ICU patients undergoing endotracheal intubation or tracheostomy were included. Individual effect sizes were standardised, and a meta-analysis was conducted to calculate the pooled effect size by using a random-effect model. The primary outcome was the oxygen saturation immediately and 2 and 5min after suctioning. The secondary outcomes were the heart rate and blood pressure after suctioning. RESULTS: We reviewed 5 RCTs including 337 patients. Oxygen saturation was significantly higher in the non-NS group than in the NS group 5min after suctioning. The pooled mean difference in oxygen saturation was -1.14 (95% confidence interval: -2.25 to -0.03). The heart rate and blood pressure did not differ significantly between the non-NS and NS groups. CONCLUSION: NS instillation before suctioning does not benefit patients undergoing endotracheal intubation or tracheostomy. Moreover, it reduces oxygen saturation 5min after suction. However, our reviewed studies had a low methodological quality. Thus, additional studies involving large-scale RCTs are warranted.

Imported Chikungunya Virus Strains, Taiwan, 2006-2014.

We identified 78 imported chikungunya cases in Taiwan during 2006-2014. Sixty-six (84.6%) cases were initially suspected to be dengue, which indicates the necessity for laboratory diagnostics in differentiation between dengue and chikungunya. Results also emphasize the need for active surveillance of febrile illness at points of entry.

Susceptibility of Aedes albopictus and Aedes aegypti to three imported Chikungunya virus strains, including the E1/226V variant in Taiwan.

BACKGROUND/PURPOSE: An E1/226V variant Chikungunya virus (CHIKV) efficiently transmitted by Aedes albopictus to humans poses a significant threat to public health for those areas with the presence of Aedes albopictus, including Taiwan. METHODS: We infected three imported CHIKV isolates including the E1/226V variant with Ae. albopictus and Aedes aegypti in the laboratory to understand the disease risk. Viral RNA was measured by real time reverse transcription polymerase chain reaction. RESULTS: The viral susceptibility varied by virus strain and mosquito species and strain. The Asian virus strain started to replicate at 5-6 days post infection (dpi) with the maximum virus yield, ranging from 10(3.63) to 10(3.87) at 5-10 dpi in both species. The variant CHIKV Central/East/South African (CESA) virus genotype replicated earlier at 1 dpi with the maximum virus yield ranging from 10(5.63) to 10(6.52) at 3-6 dpi in Ae. albopictus females while the nonvariant virus strain replicated at 1-2 dpi with the maximum virus yield ranging from 10(5.51) to 10(6.27) at 6-12 dpi. In Ae. aegypti, these viruses replicated at 1-2 dpi, with maximum yields at 4-5 dpi (range from 10(5.38) to 10(5.62)). CONCLUSION: We concluded that the risk of CHIKV in Taiwan is high in all distribution areas of Ae. aegypti and Ae. albopictus for the CESA genotype and that the E1/226V variant virus strain presents an even higher risk.

Combined effects of maternal inflammation and neonatal hyperoxia on lung fibrosis and RAGE expression in newborn rats.

BACKGROUND: Receptors for advanced glycation end products (RAGE) have been implicated in fibrotic processes. We hypothesized that lung fibrosis induced by maternal lipopolysaccharide (LPS)-mediated inflammation and neonatal hyperoxia involves RAGE in newborn rats. METHODS: Pregnant Sprague-Dawley rats received intraperitoneal injections of LPS or normal saline (NS) on 20 and 21 d of gestation. The pups were reared in room air (RA) or an O2-enrich atmosphere (O2), creating the four study groups, NS + RA, NS + O2, LPS + RA, and LPS + O2. The O2 treatment was >95% O2 for 7 d, followed by 60% O2 for 14 d. RESULTS: Rat pups born to LPS-injected dams exhibited significantly higher lung interferon-γ and interleukin-1ß (IL-1ß) on postnatal day 7 than the pups born to NS-injected dams. Rat pups reared in hyperoxia expressed higher lung IL-10 on postnatal day 7, compared with the RA-reared pups. The LPS + O2 group had significantly higher total collagen and transforming growth factor-ß1 on postnatal days 7 and 21 than the NS+RA group. RAGE mRNA and sRAGE protein expression were significantly lower in the LPS + O2 group on postnatal day 7 than the NS+RA group. CONCLUSION: RAGE may be involved in the pathogenesis of lung fibrosis induced by maternal systemic inflammation and postnatal hyperoxia in rat neonates.

Comparison of domiciliary oxygen using liquid oxygen and concentrator in northern Taiwan.

BACKGROUND/PURPOSE: Long-term oxygen therapy has become standard treatment for patients with chronic respiratory insufficiency. However, patterns of long-term home oxygen therapy have not been well studied in Taiwan. Oxygen concentrator systems are commonly used in Taiwan, but liquid oxygen delivery systems are portable and may provide advantages over the concentrator system. This study compared oxygen usage between patients from a liquid oxygen group (LOG) and an oxygen concentrator group (OCG). The authors also assessed the physiologic responses of patients with chronic obstructive pulmonary disease (COPD) to ambulatory oxygen use at home. METHODS: The study used a retrospective, cross-sectional, observational survey design. The LOG comprised 42 patients, and the OCG comprised 102 patients. We recruited participants in northern Taiwan from July 2009 to April 2010. The questionnaire instruments that were used to collect data consisted of three parts: demographic characteristics, devices used in respiratory care, and activity status with portable oxygen. Two-minute walking tests were performed on COPD patients in their homes. RESULTS: COPD was the most common diagnosis in our study, with more than 50% of patients who received oxygen long term in both groups having received this diagnosis. The LOG used oxygen for an average of 21.7 hours per day, whereas OCG averaged 15.2 hours per day (p<0.001). In the OCG, 92.2% of patients used a concentrator alone, whereas 23.8% of the LOG used liquid oxygen alone (p<0.001). The LOG patients were involved in significantly more outdoors activities (p=0.002) and reported traveling with oxygen more often (p<0.001) than the OCG patients. For patients with the same dyspnea level of COPD severity, those using liquid oxygen had a lower increase in pulse rate after the walking test, in comparison with the concentrator users. CONCLUSION: Patients in the LOG used oxygen for longer hours, went on more outings, and were more likely to travel with oxygen than patients in the OCG. Being ambulatory with liquid oxygen might enable patients with COPD to walk more effectively.

Epidemiology of Murine Typhus in Taiwan from 2013 to 2020.

Murine typhus is a flea-borne disease caused by Rickettsia typhi infection. The disease is a notifiable infectious disease in Taiwan. Specimens from suspected cases are required to be sent to the Taiwan Centers for Disease Control and Prevention for laboratory diagnosis. In this study, 204 cases of murine typhus were identified by bacterial isolation, real-time polymerase chain reaction, or indirect immunofluorescence assay between 2013 and 2020. The average incidence rate was 0.11/100,000 person-years (95% CI: 0.08-0.13). Murine typhus occurred throughout the year, but it was most prevalent in summer (May to August). The majority of patients were males (75%), residents of Kaohsiung city (31%), and worked in agriculture, forestry, fishing, and animal husbandry (27%). Fever was the most common symptom, present in 95.6% of patients, followed by headache (41%), myalgia (33%), and liver dysfunction (33%). Only 13% of patients had a rash. Up to 80% of cases were among hospitalized patients, and 43% of patients developed severe manifestations. Serological assays also indicated coinfection events. Seven patients showed a 4-fold increase in antibody titers against Orientia tsutsugamushi (N = 2), Coxiella burnetii (n = 2), and Leptospira (N = 3). In conclusion, murine typhus is an endemic and important zoonotic rickettsial disease in Taiwan that cannot be ignored. Further epidemiological surveillance and clinical characteristics should be continuously investigated to prevent and control murine typhus.

Amelioration of superoxide dismutase on ventilator-induced lung injury by suppressing leukocyte in the lungs and systemic circulation.

Superoxide dismutase (SOD) is a free radical scavenger and a broad-spectrum antioxidant. Its anti-inflammatory and immunomodulatory effects have recently been noted. We studied the effects of this antioxidant on lung damage, oxidative stress, and inflammation in a model of ventilator-induced lung injury (VILI), using 8- to 12-wk-old Sprange-Dawley rats (n = 40). Animals were randomized and evenly divided into two experimental groups, low tidal volume (V(T)) ventilation (V(T) = 9 ml/kg) and high V(T) ventilation (V(T) = 28 ml/kg). Each group was evenly divided into two subgroups: ten animals were treated with superoxide dismutase (SOD; 10,000 U/kg i.v., 2 h prior to the ventilation) and the rests were treated with vehicle. Lung injury was evaluated by histological examination, and cells counts of red blood cells (RBC) and white blood cells (WBC) in the alveoli and the septal wall thickness in lung tissues and serum lactate dehydrogenase (LDH). The lung permeability was assessed by the wet-to-dry weight ratio (W/D), lung weight to body weight ratio (LW/BW) and protein concentration in broncholavage fluid (BALF). Levels of oxidative stress and lipid peroxidation in the lungs were evaluated by tissue malondialdehyde (MDA) and methylguanidine (MG) in BALF, respectively. SOD pretreatment significantly decreased WBC counts in systemic circulation and in alveoli, and effectively attenuated high V(T) ventilation induced lung injury by reducing hyaline membrane development, septal wall thickness, lung W/D and LW/BW and serum LDH in relation to those of the control. In addition, lung tissues MDA and MG in BALF were also notably reduced.

Risk of herpes zoster in CKD: a matched-cohort study based on administrative data.

BACKGROUND: Immune system dysregulation is associated with end-stage renal disease. Although decreased cellular immunity increases susceptibility to herpes zoster, the risk of herpes zoster in patients with earlier stages of chronic kidney disease (CKD) is unclear. STUDY DESIGN: A matched-cohort study. SETTING & PARTICIPANTS: Data from the Taiwan Longitudinal Health Insurance Database (LHID) for 2004-2006 were analyzed. The study cohort included patients 18 years or older given a diagnosis of CKD (excluding patients treated by dialysis or transplant) in 2004-2005 (n = 13,321). The comparison cohort (n = 66,605) included 5 randomly selected age- and sex-matched controls for each patient in the study cohort. PREDICTOR: CKD. Incident cases of CKD were identified using the Taiwan LHID. CKD was ascertained from International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. OUTCOMES: Herpes zoster, ascertained from ICD-9-CM codes. All participants were followed up from the date of cohort entry until they developed herpes zoster or the end of 2006. Cox proportional hazard regressions were performed to compare the hazard rates of herpes zoster in the CKD cohort and the age- and sex-matched comparison cohort. RESULTS: We identified 13,321 patients with a diagnosis of CKD who matched the inclusion criteria. 1,602 patients developed herpes zoster during the study period, of whom 353 were from the CKD cohort and 1,249 were from the comparison cohort. After adjusting for potential confounding factors, CKD was associated independently with greater risk of herpes zoster (HR, 1.60; 95% CI, 1.41-1.81). LIMITATIONS: Some patients with CKD or herpes zoster may have chosen not to seek medical care. Misclassification of CKD due to use of diagnostic codes also is a limitation. CONCLUSIONS: This population-based cohort study indicated that patients with CKD are at increased risk of herpes zoster compared with the general population.

Preventive use of noninvasive ventilation after extubation: a prospective, multicenter randomized controlled trial.

BACKGROUND: The effectiveness of noninvasive ventilation (NIV) after extubation in preventing post-extubation respiratory failure is still controversial. METHODS: We conducted a prospective, multicenter randomized controlled study involving patients on mechanical ventilation for > 48 hours who tolerated a 2-hour spontaneous breathing trial and were subsequently extubated. The patients were randomized to NIV or standard medical therapy. Re-intubation rate within 72 hours was the primary outcome measure. Multivariable logistic regression analysis was used to determine predictors for extubation failure. RESULTS: We randomized 406 patients to either NIV (no. = 202) or standard medical therapy (no. = 204). The 2 groups had similar baseline clinical characteristics. There were no differences in extubation failure (13.2% in control and 14.9% in NIV), intensive care unit or hospital mortality. Cardiac failure was a more common cause of extubation failure in control than in NIV. There was no difference in rapid shallow breathing index (RSBI) in extubation failure patients between control (80) and NIV (73). When using data from all patients, we found Acute Physiology and Chronic Health Evaluation (APACHE II) scores (odds ratio [OR] 1.13, 95% CI 1.07-1.20, P < .001), maximal inspiratory pressure (OR 1.04, 95% CI 1.00-1.08, P = .03), and RSBI (OR 1.03, 95% CI 1.02-1.05, P < .001) to be predictors of extubation failure. Abundant secretions were the most common reason (35.1%) for extubation failure identified by attending physicians. CONCLUSIONS: Preventive use of NIV after extubation in patients who passed spontaneous breathing trial did not show benefits in decreasing extubation failure rate or the mortality rate.

Synthesis and antibacterial activities of novel 4-hydroxy-7-hydroxy- and 3-carboxycoumarin derivatives.

Coumarin derivatives are used as fluorescent dyes and medicines. They also have some notable physiological effects, including the acute hepatoxicity and carcinogenicity of certain aflatoxins, the anticoagulant action of dicoumarol, and the antibiotic activity of novobicin and coumerymycin A1. Because the number of drug resistant strains is increasing at present, the synthesis of new antibacterial compounds is one of the critical methods for treating infectious diseases. Therefore, a series of coumarinsubstituted derivatives, namely 4-hydroxy- and 7-hydroxycoumarins, and 3-carboxycoumarins were synthesized. 4-Hydroxycoumarin derivatives 4a-c underwent rearrangement reactions. Both 4- and 7-hydroxycoumarins were treated with activated aziridines which produced series of ring-opened products 7, 8, 10, and 11. 3-Carboxy-coumarin amide dimer derivatives 14-21 were prepared by reacting aliphatic alkylamines and alkyldiamines with PyBOP and DIEA. In this study, we use a new technique called modified micro-plate antibiotic susceptibility test method (MMAST), which is more convenient, more efficient, and more accurate than previous methods and only a small amount of the sample is required for the test. Some of the compounds were produced by reactions with acid anhydrides and demonstrated the ability to inhibit Gram-positive microorganisms. The dimer derivatives displayed lower antibacterial activities.

Correction: Molecular epidemiology of scrub typhus in Taiwan during 2006-2016.

[This corrects the article DOI: 10.1371/journal.pntd.0010369.].

Molecular epidemiology of scrub typhus in Taiwan during 2006-2016.

Scrub typhus is the most common endemic vector-borne disease in Taiwan. We identified a total of 4,857 laboratory-confirmed cases during 2006-2016 with hyperendemic foci on offshore islands, including Penghu (778 cases, 16.0%) and Kinmen (716 cases, 14.7%), and eastern Taiwan, including Taitung (628 cases, 12.9%) and Hualien (508 cases, 10.5%). Scrub typhus cases occur year-round throughout Taiwan, with a summer peak in June and July. A total of 545 O. tsutsugamushi isolates were successfully obtained from patients infected in diverse geographic areas, including Taiwan and three offshore islands, and the complete open reading frame of the 56 kDa type-specific antigen gene (tsa56) sequence of these isolates was examined. High phylogenetic diversity was found in these isolates, which could be grouped into 36 distinct sequence types. Most isolates belonged to the Karp (49.9%; 272/545), followed by the TW-22 (17.8%; 97/454) and Kawasaki (14.7%; 80/545) genotypes. In conclusion, our data indicate the widespread presence of tsa56 genotypes closely related to Thailand and Korean strains and the presence of the unique endemic strains TW-12, TW-22, TW-29, and TW-36 in Taiwan.

Associations between lung-deposited dose of particulate matter and culture-positive pulmonary tuberculosis pleurisy.

Epidemiological studies identified the relationship between air pollution and pulmonary tuberculosis. Effects of lung-deposited dose of particulate matter (PM) on culture-positive pulmonary tuberculosis remain unclear. This study investigates the association between lung-deposited dose of PM and pulmonary tuberculosis pleurisy. A case-control study of subjects undergoing pleural effusion drainage of pulmonary tuberculosis (case) and chronic heart failure (control) was conducted. Metals and biomarkers were quantified in the pleural effusion. The air pollution exposure was measured and PM deposition in the head, tracheobronchial, alveolar region, and total lung region was estimated by Multiple-path Particle Dosimetry (MPPD) Model. We performed multiple logistic regression to examine the associations of these factors with the risk of tuberculosis. We observed that 1-µg/m3 increase in PM10 was associated with 1.226-fold increased crude odds ratio (OR) of tuberculosis (95% confidence interval (CI): 1.023-1.469, p<0.05), 1-µg/m3 increase in PM2.5-10 was associated with 1.482-fold increased crude OR of tuberculosis (95% CI: 1.048-2.097, p < 0.05), 1-ppb increase in NO2 was associated with 1.218-fold increased crude OR of tuberculosis (95% CI: 1.025-1.447, p < 0.05), and 1-ppb increase in O3 was associated with 0.735-fold decreased crude OR of tuberculosis (95% CI: 0.542 0.995). We observed 1-µg/m3 increase in PM deposition in head and nasal region was associated with 1.699-fold increased crude OR of tuberculosis (95% CI: 1.065-2.711, p < 0.05), 1-µg/m3 increase in PM deposition in tracheobronchial region was associated with 1.592-fold increased crude OR of tuberculosis (95% CI: 1.095-2.313, p < 0.05), 1-µg/m3 increase in PM deposition in alveolar region was associated with 3.981-fold increased crude OR of tuberculosis (95% CI: 1.280-12.386, p < 0.05), and 1-µg/m3 increase in PM deposition in total lung was associated with 1.511-fold increased crude OR of tuberculosis (95% CI: 1.050-2.173, p < 0.05). The results indicate that particle deposition in alveolar region could cause higher risk of pulmonary tuberculosis pleurisy than deposition in other lung regions.

Physical training is beneficial to functional status and survival in patients with prolonged mechanical ventilation.

BACKGROUND/PURPOSE: Early physical training is necessary for severely deconditioned patients undergoing prolonged mechanical ventilation (PMV), because survivors often experience prolonged recovery. Long-term outcomes after physical training have not been measured; therefore, we investigated outcome during a 1-year period after physical training for the PMV patients. METHODS: We conducted a prospective randomized control trial in a respiratory care center. Thirty-four patients were randomly assigned to the rehabilitation group (n = 18) and the control group (n = 16). The rehabilitation group participated in supervised physical therapy training for 6 weeks, and continued in an unsupervised maintenance program for 6 more weeks. The functional independence measurement (FIM) was used to assess functional status. Survival status during the year after enrollment, the number of survivors discharged, and the number free from ventilator support were collected. These outcome parameters were assessed at entry, immediately after the 6 weeks physical therapy training period, after 6 weeks unsupervised maintenance exercise program, and 6 months and 12 months after study entry. RESULTS: The scores of total FIM, motor domain, cognitive domain, and some sub-items, except for the walking/wheelchair sub-item, increased significantly in the rehabilitation group at 6 months postenrollment, but remained unchanged for the control group. The eating, comprehension, expression, and social interaction subscales reached the 7-point complete independence level at 6 months in the rehabilitation group, but not in the control group. The 1-year survival rate for the rehabilitation group was 70%, which was significantly higher than that for the control group (25%), although the proportion of patients discharged and who were ventilator-free in the rehabilitation and control groups did not differ significantly. CONCLUSION: Six weeks physical therapy training plus 6 weeks unsupervised maintenance exercise enhanced functional levels and increased survival for the PMV patients compared with those with no such intervention. Early physical therapy interventions are needed for the PMV patients in respiratory care centers.

Effects of pulmonary rehabilitation program on amyotrophic lateral sclerosis: A meta-analysis of randomized controlled trials.

BACKGROUND: Patients with amyotrophic lateral sclerosis (ALS) develop respiratory failure and progressive muscle weakness. The effects of pulmonary rehabilitation on the lung function of patients with ALS are unclear. OBJECTIVE: Through this meta-analysis of randomized controlled trials (RCTs), we evaluated the effects of pulmonary rehabilitation, such as type of treatment, on patients with ALS and compared the effectiveness of this treatment. METHODS: PubMed, EMBASE, Web of Science, and Cochrane databases were searched until December 2020. The methodological quality of each study was assessed using the updated Cochrane Risk of Bias tool (RoB 2.0). Data were analyzed using Review Manager version 5.4 (Cochrane Collaboration, Oxford, England), and the meta-analysis was performed in accordance with Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) guidelines. RESULTS: Of 2168 articles, 10 trials were reviewed; among these trials, two focused on respiratory training and eight on physical exercise, three of which involved a combination of aerobic and resistance training. Our meta-analysis demonstrated no difference in the ALSFRS-R score and % FVC among patients with ALS. CONCLUSIONS: Respiratory training or physical exercise did not significantly affect the ALSFRS-R score and % FVC of patients with ALS. At 12 months after intervention, the ALSFRS-R score in the physical exercise group was higher than that in the usual care group. Further clinical trials are warranted to develop approaches for improving the lung function of patients with ALS.

High-flow nasal cannula for reducing hypoxemic events in patients undergoing bronchoscopy: A systematic review and meta-analysis of randomized trials.

BACKGROUND: Patients undergoing bronchoscopic procedures may develop hypoxemia and severe complications. High-flow nasal cannula (HFNC) may prevent hypoxemic events during bronchoscopy. We conducted a systematic review of randomized controlled trials (RCTs) to evaluate the effectiveness of HFNC in these patients. METHODS: We conducted a search in PubMed, Embase, and the Cochrane Library for RCTs published before November 2021. Individual effect sizes were standardized, and a meta-analysis was performed to calculate the pooled effect size using random-effects models. The primary outcome was the incidence of hypoxemic events (oxygen saturation [SpO2] < 90%) during bronchoscopy. Secondary outcomes included the incidence of interrupted bronchoscopy due to desaturation, lowest SpO2 during bronchoscopy, partial pressure of oxygen (PaO2), partial pressure of carbon dioxide (PaCO2), end-tidal CO2 (EtCO2) at the end of bronchoscopy, and the incidence of intubation after the procedure. RESULTS: Five trials involving 257 patients were reviewed. The incidence of hypoxemic events was lower in the HFNC group than in the conventional oxygen therapy group (risk ratio, 0.25; 95% confidence interval [CI], 0.14-0.42). The lowest SpO2 during the procedure was significantly higher in the HFNC group than in the conventional oxygen therapy group (weighted mean difference [WMD], 7.12; 95% CI, 5.39-8.84). PaO2 at the end of the procedure was significantly higher in the HFNC group than in the conventional oxygen therapy group (WMD, 20.36; 95% CI, 0.30-40.42). The incidence of interrupted bronchoscopy due to desaturation, PaCO2 and EtCO2 at the end of the procedure, and the incidence of intubation after the procedure were not significantly different between groups. CONCLUSIONS: HFNC may reduce the incidence of hypoxemic events and improve oxygenation in patients undergoing bronchoscopy.