Association of tissue oxygen saturation levels with skeletal muscle injury in the critically ill.

This study aimed to investigate the association between the level of tissue oxygen saturation (StO2) and quadriceps/skeletal muscle dysfunction, measured using the Medical Research Council (MRC) scale and ultrasonography, in critically ill patients. Thirty-four patients hospitalized at the Critical Care Medicine Center of Kindai University Hospital, between January 2022 and March 2023, were enrolled in this study. The StO2 of the quadriceps muscle was measured via near-infrared spectroscopy. Muscle atrophy was measured by the thickness, cross-sectional area (CSA), and echo intensity of the rectus femoris (RF). These values were evaluated every alternate day until 13 days after admission or until discharge, whichever occurred first. Muscle weakness was assessed using the sum score of the MRC scale (MRC-SS), with the patient sitting at bedside. The mean age of the patients was 67.3 ± 15.3 years, and 20 (59%) were men. Seven patients (21%) were admitted for trauma, and 27 (79%) were admitted for medical emergencies or others. The mean score for the MRC-SS was 51.0 ± 7.9 points. RF thickness and CSA significantly decreased after day 7 (p < 0.05). There were no significant changes in StO2 levels during hospitalization. However, there were positive correlations between the nadir StO2 during hospitalization and MRC-SS, and changes in RF thickness and CSA at discharge (r = 0.41, p = 0.03; r = 0.37, p = 0.03; and r = 0.35, p = 0.05, respectively). StO2 in the quadriceps muscle may be useful for predicting muscle atrophy and dysfunction in patients with critical illnesses.

Evaluation of patients with chronic obstructive pulmonary disease by maximal inspiratory pressure and diaphragmatic excursion with ultrasound sonography.

BACKGROUND: Decreased respiratory muscle strength and muscle mass is key in diagnosing respiratory sarcopenia. However, the role of reduced diaphragm activity, expressed as the maximal level of diaphragmatic excursion (DEmax), in diagnosing respiratory sarcopenia in patients with chronic obstructive pulmonary disease (COPD) remains unclear. This study aimed to characterize patients with COPD and low DEmax and maximal inspiratory pressure (MIP), a measure of inspiratory muscle strength, and assess the role of DEmax in respiratory sarcopenia. METHODS: Patients with COPD underwent spirometry, exercise tolerance (VO2peak) test, and MIP measurement. DEmax and sternocleidomastoid thickness at the maximal inspiratory level (TscmMIL) were assessed using ultrasound sonography. RESULTS: Overall, 58 patients with COPD (median age, 76 years; median %FEV1, 51.3 %) were included, 28 of whom showed a %MIP of ≥80 %, defined as having preserved MIP. Based on the %MIP of 80 % and median value of DEmax (48.0 mm) as thresholds, the patients were stratified into four groups: both-high (n = 18), %MIP-alone low (n = 11), DEmax-alone low (n = 10), and both-low (n = 19) groups. The both-low group exhibited the lowest %FEV1, Δinspiratory capacity, VO2peak, and TscmMIL, and these values were significantly lower than those of the both-high group. Except for %FEV1, these values were significantly lower in the both-low group than in the %MIP-alone low group despite adjusting DEmax level for body mass index. CONCLUSION: Measuring DEmax along with MIP can characterize patients with COPD, reduced exercise capacity, and decreased accessory respiratory muscle mass and can help diagnose respiratory sarcopenia.

Quantitative emphysema on computed tomography imaging of chest is a risk factor for prognosis of esophagectomy: A retrospective cohort study.

The low attenuation area percentage (LAA%) is gaining popularity. LAA% is an index of quantitative emphysema on computed tomography (CT) imaging of the chest. This study aims to retrospectively investigate whether preoperative LAA% is associated with postoperative prognosis in patients with esophageal cancer who were scheduled for esophagectomy. From January 2016 to March 2020, 105 patients with esophageal cancer underwent esophagectomy via right thoracotomy and neoadjuvant chemotherapy. A Synapse Vincent volume analyzer (Fujifilm Medical, Tokyo, Japan) was used for measurement. The software automatically quantified LAA% using a threshold of less than - 950 Hounsfield units on CT images of lung regions. Cox proportional hazard analyses were performed in univariable and multivariable forms. Estimates of the receiver operating curve are used to determine the cutoff value for death of LAA%, and the binary value is then inserted into Cox proportional hazard analyses. The preoperative LAA% cutoff value was ≥ 6.3%. Patients with a preoperative LAA% ≥6.3% had a significantly worse prognosis than those with a preoperative LAA% of < 6.3%. LAA% ≥6.3% (hazard ratio: 6.76; 95% confidence interval: 2.56-17.90, P < .001) was the most influential preoperative factor for overall survival after esophagectomy in multivariate Cox proportional hazard analyses. LAA% is one of the preoperative risk factors for survival after esophagectomy and an indicator of lung condition using routinely performed preoperative CT images. We quantified the extent of preoperative emphysema in patients with esophageal cancer, who were scheduled for surgery, and for the first time, reported LAA% as one of the preoperative risk factors for survival after esophagectomy.

Diaphragm dome height on chest radiography as a predictor of dynamic lung hyperinflation in COPD.

Background and objective: Dynamic lung hyperinflation (DLH) can play a central role in exertional dyspnoea in patients with COPD. Chest radiography is the basic tool for assessing static lung hyperinflation in COPD. However, the predictive capacity of DLH using chest radiography remains unknown. This study was conducted to determine whether DLH can be predicted by measuring the height of the right diaphragm (dome height) on chest radiography. Methods: This single-centre, retrospective cohort study included patients with stable COPD with pulmonary function test, cardiopulmonary exercise test, constant load test and pulmonary images. They were divided into two groups according to the median of changes of inspiratory capacity (ΔIC=IC lowest - IC at rest). The right diaphragm dome height and lung height were measured on plain chest radiography. Results: Of the 48 patients included, 24 were classified as having higher DLH (ΔIC ≤-0.59 L from rest; -0.59 L, median of all) and 24 as having lower DLH. Dome height correlated with ΔIC (r=0.66, p<0.001). Multivariate analysis revealed that dome height was associated with higher DLH independent of % low attenuation area on chest computed tomography and forced expiratory volume in 1 s (FEV1) % predicted. Furthermore, the area under the receiver operating characteristic curve of dome height to predict higher DLH was 0.86, with sensitivity and specificity of 83% and 75%, respectively, at a cut-off of 20.5 mm. Lung height was unrelated to ΔIC. Conclusion: Diaphragm dome height on chest radiography may adequately predict higher DLH in patients with COPD.

Sternocleidomastoid Muscle Thickness Correlates with Exercise Tolerance in Patients with COPD.

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) have difficulties inhaling as the diaphragm becomes flattened and weakened due to lung hyperinflation. This weakened respiratory function is compensated for by the increased activity of the accessory respiratory muscles, such as the sternocleidomastoid muscle (SCM). OBJECTIVES: This study aimed to evaluate the difference in the SCM thickening fraction (SCM TF) of each respiratory phase (end-expiration, resting inspiration, and end-inspiration), as measured using ultrasonography (US), between patients with COPD and control subjects. We also evaluate the correlation between the SCM TF of each respiratory phase and exercise tolerance in patients with COPD. METHODS: Patients with COPD (n = 44) and age-matched controls (n = 20) underwent US for determination of the SCM TF. Ventilation parameters, including the peak oxygen uptake (peak VO2) and the change in the inspiratory capacity, were measured during cardiopulmonary exercise testing. The SCM thickness and TF was measured during end-expiration, resting breathing, and end-inspiration. RESULTS: The SCM was significantly thinner in patients with COPD than in controls at end-expiration. The increase in the SCM TF from end-expiration to end-inspiration in patients with COPD did not differ significantly from that in control subjects. In contrast, the SCM TF from end-expiration to resting inspiration was significantly greater in patients with COPD than in control subjects. The peak VO2 was strongly positively correlated with the SCM TF from end-expiration to end-inspiration in patients with COPD (r = 0.71, p < 0.01). CONCLUSIONS: The SCM may be thinner in patients with COPD than in controls. The SCM TF may also be associated with exercise tolerance.

Adipose-derived exosomes block muscular stem cell proliferation in aged mouse by delivering miRNA Let-7d-3p that targets transcription factor HMGA2.

Sarcopenia is an aging-associated attenuation of muscular volume and strength and is the major cause of frailty and falls in elderly individuals. The number of individuals with sarcopenia is rapidly increasing worldwide; however, little is known about the underlying mechanisms of the disease. Sarcopenia often copresents with obesity, and some patients with sarcopenia exhibit accumulation of peri-organ or intra-organ adipose tissue as ectopic fat deposition, including atrophied skeletal muscle. In this study, we showed that transplantation of the perimuscular adipose tissue (PMAT) to the hindlimb thigh muscles of young mice decreased the number of integrin α7/CD29-double positive muscular stem/progenitor cells and that the reaction was mediated by PMAT-derived exosomes. We also found that the inhibition of cell proliferation was induced by Let-7d-3p miRNA that targets HMGA2, which is an important transcription factor for stem cell self-renewal, in muscular stem/progenitor cells and the composite molecular reaction in aged adipocytes. Reduction of Let-7 miRNA repressor Lin28 A/B and activation of nuclear factor-kappa B signaling can lead to the accumulation of Let-7d-3p in the exosomes of aged PMAT. These findings suggest a novel crosstalk between adipose tissue and skeletal muscle in the development of aging-associated muscular atrophy and indicate that adipose tissue-derived miRNAs may play a key role in sarcopenia.

Effectiveness of Rehabilitation for Cancer Patients with Bone Metastasis.

Objectives: Advances in cancer treatment have led to extended survival, and, as a result, the number of patients with bone metastases is increasing. Activities of daily living (ADL) decrease with bone metastasis and the need for rehabilitation is increasing. This study examined the effects of rehabilitation in patients with bone metastases. Methods: We retrospectively reviewed data of cancer patients with bone metastasis who received rehabilitation between 2016 and 2018. Efficacy of rehabilitation was evaluated in 92 patients as the change in the Functional Independence Measure (FIM) score divided by rehabilitation days (FIM change/day) and assessed by different metastatic sites. Results: Overall FIM scores significantly improved after rehabilitation. Moreover, FIM change/day improved in patients with pelvic metastases (n=44) more than in patients with other metastatic sites (n=48) (P=0.015). In FIM motor components, improvements in toilet, tub/shower, walk/wheelchair, and stairs were significantly greater in patients with pelvic metastasis than in those with other metastasis sites. Conclusions: Rehabilitation improved ADL status to a greater extent in patients with pelvic metastases than in those with other metastasis sites. Patients with pelvic metastases may fear fractures, limiting their ADL, but rehabilitation could eliminate this fear and improve FIM.

Decreased Tongue Strength is Related to Skeletal Muscle Mass in COPD Patients.

Dysphagia is frequently observed in patients with chronic obstructive pulmonary disease (COPD). Decreased tongue strength is one of the causes of dysphagia, and it is often observed in patients with sarcopenia. Sarcopenia is also frequently observed in COPD patients. We hypothesized that tongue strength is lower in COPD patients compared to normal subjects. This was a single-center, observational, cross-sectional study. Maximum tongue pressure (MTP) was measured in 27 patients with COPD and 24 age-matched control subjects. We also evaluated handgrip strength, gait speed, and appendicular skeletal muscle mass to define subjects as having sarcopenia. We used bioelectrical impedance analysis to assess body composition. The eating assessment test-10 was used to diagnose dysphagia. MTP was significantly lower in COPD patients than in control subjects (33.8 ± 8.4 vs 38.0 ± 5.3; p = 0.032). All measures of muscle and fat free body mass, handgrip strength, and gait speed were also significantly lower in COPD patients compared to control subjects (p < 0.01). The prevalence of sarcopenia in COPD patients was higher than that in control subjects (6/27 versus 0/24; p = 0.007), but the prevalence of dysphagia was not different between groups (COPD: 5/27, versus control: 1/24; p = 0.112). MTP was moderately correlated with skeletal muscle mass index (r = 0.56, p = 0.003) and handgrip strength (r = 0.43, p = 0.027) in COPD patients. Tongue strength was lower in COPD patients compared to normal subjects, and decreased tongue strength may be correlated with sarcopenia in COPD patients.

Diaphragmatic excursion is correlated with the improvement in exercise tolerance after pulmonary rehabilitation in patients with chronic obstructive pulmonary disease.

BACKGROUND: In patients with chronic obstructive pulmonary disease (COPD), the maximum level of diaphragm excursion (DEmax) is correlated with dynamic lung hyperinflation and exercise tolerance. This study aimed to elucidate the utility of DEmax to predict the improvement in exercise tolerance after pulmonary rehabilitation (PR) in patients with COPD. METHODS: This was a prospective cohort study. Of the 62 patients with stable COPD who participated in the outpatient PR programme from April 2018 to February 2021, 50 completed the programme. Six-minute walk distance (6MWD) was performed to evaluate exercise tolerance, and ultrasonography was performed to measure DEmax. Responders to PR in exercise capacity were defined as patients who demonstrated an increase of > 30 m in 6MWD. The receiver operating characteristic (ROC) curve was used to determine the cut-off point of DEmax to predict responses to PR. RESULTS: Baseline levels of forced expiratory volume in 1 s, 6MWD, maximum inspiratory pressure, DEmax and quadriceps muscle strength were significantly higher, and peak dyspnoea of modified Borg (mBorg) scale score was lower in responders (n = 30) than in non-responders (n = 20) to PR (p < 0.01). In multivariate analysis, DEmax was significantly correlated with an increase of > 30 m in 6MWD. The area under the ROC curve of DEmax to predict responders was 0.915, with a sensitivity and specificity of 83% and 95%, respectively, at a cut-off value of 44.9 mm of DEmax. CONCLUSION: DEmax could adequately predict the improvement in exercise tolerance after PR in patients with COPD.

Effect of Pulmonary Rehabilitation on Erector Spinae Muscles in Individuals With COPD.

BACKGROUND: A recent paper reported that low muscle mass in the erector spinae muscles (ESM) was strongly associated with poor prognosis and declining muscle mass over time in subjects with COPD. However, effects of pulmonary rehabilitation (PR), if any, on ESM mass have not been reported. We hypothesized that PR reduces the annual decline in ESM mass. METHODS: This was a retrospective cohort study. Thirty-nine subjects with COPD who received PR and underwent chest computed tomography before and after PR were evaluated (rehabilitation group). We also evaluated 39 age-matched subjects with COPD who did not receive PR (nonrehabilitation group). Data were collected from August 2010 until March 2020 in both groups. The ESM cross-sectional area (ESMCSA) was measured using axial computed tomography images, and annual changes were calculated. The 6-min walk distance (6MWD) was measured before and after PR; the minimum clinically important difference was defined as 30 m. RESULTS: ESMCSA declined in the nonrehabilitation group over time (-116.0 ± 141.2 mm2/y) but increased in the PR group (51.0 ± 95.3 mm2/y; P < .001). The annual increase in ESMCSA was significantly higher among subjects with an increase in 6MWD that exceeded the minimum clinically important difference compared with nonresponders in the rehabilitation group. The annual change in ESMCSA was negatively correlated with comorbidity index, and triple therapy (long-acting ß2-agonist/long-acting muscarinic antagonist/inhaled corticosteroid) had a favorable effect on annual change in ESMCSA. Multiple regression analysis revealed that only PR was an independent factor for annual change in ESMCSA. CONCLUSIONS: ESM mass was shown to decline yearly in subjects with COPD. The annual decline in muscle mass was reduced by PR.

Effect of pulmonary rehabilitation programs including lower limb endurance training on dyspnea in stable COPD: A systematic review and meta-analysis.

Pulmonary rehabilitation (PR) is recommended as an effective treatment for patients with chronic obstructive pulmonary disease (COPD). Previous meta-analyses showed that PR improves exercise capacity and health-related quality of life (HRQOL). However, they did not evaluate the effect of PR on the sensation of dyspnea. We searched six databases in May 2019 for randomized controlled trials (RCTs) that examined PR, including supervised lower limb endurance training as a minimal essential component that was continued for 4-12 weeks, in patients with stable COPD, with changes from baseline dyspnea as a primary outcome. Secondary outcomes were changes in exercise capacity, HRQOL, activity of daily life (ADL), physical activity (PA), and adverse events. We calculated the pooled weighted mean difference (MD) using a random effects model. We identified 42 studies with 2150 participants. Compared with the control, PR improved dyspnea, as shown using the British Medical Research Council (MRC) questionnaire (MD, -0.64; 95% CI, -0.99 to -0.30; p = 0.0003), transitional dyspnea index (MD, 1.95; 95% CI, 1.09 to 2.81; p = 0.0001), modified Borg score during exercise (MD, -0.62; 95% CI, -1.10 to -0.14; p = 0.01), and Chronic Respiratory Questionnaire (CRQ) dyspnea score (MD, 0.91; 95% CI, 0.39 to 1.44; p = 0.0007). PR significantly increased exercise capacity measured by the 6 min walking distance time, peak workload, and peak VO2. It improved HRQOL measured by the St. George's Respiratory Questionnaire and CRQ, but not on PA or ADL. These results indicated that PR programs including lower limb endurance training improve dyspnea, HRQOL, and exercise capacity in patients with stable COPD.

Ability to categorize end-feel joint movement according to years of clinical experience: an experiment with an end-feel simulator.

[Purpose] Discrimination between end-feel types is difficult, and years of clinical experience is considered a factor for improving the accuracy of the discrimination. The present study investigated whether the accuracy of classification of end-feel types improves with the increase in years of clinical experience. [Participants and Methods] In total, 44 therapists (range of years of clinical experience: 1-26 years) and 13 students were included. The participants identified the type of end feel simulated by our newly developed simulator. The proportion of correct answers of the therapists was compared with that of the students. For the therapists, years of clinical experience and their awareness of end feel were examined, and their relationships with the ability to classify end-feel types were analyzed. [Results] The therapists showed a higher ability to identify end-feel type than the students. The ability of the therapists improved according to their years of clinical experience. The cutoff values for years of clinical experience to improve the ability for identifying bone-to-bone, muscular, and tissue approximations were 15, 6, and 15, respectively. The therapists who were always conscious about end feel were associated with a higher ability to classify end-feel types. [Conclusion] Our present study demonstrated that the ability to classify end feel improves with the increase in years of clinical experience.

Diaphragmatic excursion correlates with exercise capacity and dynamic hyperinflation in COPD patients.

BACKGROUND: Although the pathophysiological mechanisms involved in the development of dyspnoea and poor exercise tolerance in patients with COPD are complex, dynamic lung hyperinflation (DLH) plays a central role. Diaphragmatic excursions can be measured by ultrasonography (US) with high intra- and interobserver reliability. The objective of this study was to evaluate the effect of diaphragmatic excursions as assessed by US on exercise tolerance and DLH in patients with COPD. METHODS: Patients with COPD (n=20) and age-matched control subjects (n=20) underwent US, which was used to determine the maximum level of diaphragmatic excursion (DEmax). Ventilation parameters, including the change in inspiratory capacity (ΔIC), were measured in the subjects during cardiopulmonary exercise testing (CPET). We examined the correlations between DEmax and the ventilation parameters. RESULTS: The DEmax of patients with COPD was significantly lower than that of the controls (45.0±12.8 mm versus 64.6±6.3 mm, respectively; p<0.01). The perception of peak dyspnoea (Borg scale) was significantly negatively correlated with DEmax in patients with COPD. During CPET, oxygen uptake/weight (V'O2 /W) and minute ventilation (V'E) were significantly positively correlated with DEmax, while V'E/V'O2 and V'E/carbon dioxide output (V'CO2 ) were significantly negatively correlated with DEmax in patients with COPD. DEmax was also significantly positively correlated with ΔIC, reflecting DLH, and with V'O2 /W, reflecting exercise capacity. CONCLUSION: Reduced mobility of the diaphragm was related to decreased exercise capacity and increased dyspnoea due to dynamic lung hyperinflation in COPD patients.

Involvement of Allosteric Effect and KCa Channels in Crosstalk between ß2-Adrenergic and Muscarinic M2 Receptors in Airway Smooth Muscle.

To advance the development of bronchodilators for asthma and chronic obstructive pulmonary disease (COPD), this study was designed to investigate the mechanism of functional antagonism between ß2-adrenergic and muscarinic M2 receptors, focusing on allosteric effects and G proteins/ion channels coupling. Muscarinic receptor antagonists (tiotropium, glycopyrronium, atropine) synergistically enhanced the relaxant effects of ß2-adrenergic receptor agonists (procaterol, salbutamol, formoterol) in guinea pig trachealis. This crosstalk was inhibited by iberitoxin, a large-conductance Ca2+-activated K⁺ (KCa) channel inhibitor, whereas it was increased by verapamil, a L-type voltage-dependent Ca2+ (VDC) channel inhibitor; additionally, it was enhanced after tissues were incubated with pertussis or cholera toxin. This synergism converges in the G proteins (Gi, Gs)/KCa channel/VDC channel linkages. Muscarinic receptor antagonists competitively suppressed, whereas, β2-adrenergic receptor agonists noncompetitively suppressed muscarinic contraction. In concentration-inhibition curves for β2-adrenergic receptor agonists with muscarinic receptor antagonists, EC50 was markedly decreased, and maximal inhibition was markedly increased. Hence, muscarinic receptor antagonists do not bind to allosteric sites on muscarinic receptors. ß2-Adrenergic receptor agonists bind to allosteric sites on these receptors; their intrinsic efficacy is attenuated by allosteric modulation (partial agonism). Muscarinic receptor antagonists enhance affinity and efficacy of ß2-adrenergic action via allosteric sites in ß2-adrenergic receptors (synergism). In conclusion, KCa channels and allosterism may be novel targets of bronchodilator therapy for diseases such as asthma and COPD.

Physical activity in daily life in patients with idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is characterized by progressive impairment of lung function and degradation of daily activity; however, this degradation has not been adequately elucidated. The objective of this study was to measure the physical activity of patients with IPF to determine its relationships with physiological parameters and survival rate. METHODS: In total, 31 patients with IPF and 20 age-matched healthy participants were enrolled in this study. Physical activity was assessed using a physical activity monitor. The relationships among physical activity, physiological data, questionnaire-based patient-centered data, and survival were examined. RESULTS: Physical activity, expressed as daily activity energy expenditure (AEE), was significantly lower, and the percentage of sedentary time was significantly longer in patients with IPF than in healthy participants. Moreover, AEE was moderately correlated with body-mass index, forced vital capacity, diffusing capacity of carbon monoxide, and partial arterial pressure of oxygen. Relatively strong correlation was also observed between AEE and the 6-min walk distance, but not with daily dyspnea, depression, and health-related quality of life scores. Prognostic analysis indicated that daily AEE was a significant predictor of survival. CONCLUSIONS: Patients with IPF were significantly inactive compared with age-matched healthy participants. In patients with more impaired physiological functions, the lower the physical activity was, the more was the sedentary time increased. Furthermore, lower daily physical activity resulted in significantly worse survival.

Factors associated with the effect of pulmonary rehabilitation on physical activity in patients with chronic obstructive pulmonary disease.

AIM: Although the effects of pulmonary rehabilitation (PR) have been well defined for chronic obstructive pulmonary disease (COPD), it remains controversial whether PR improves physical activity (PA). The purpose of the present study was to identify factors associated with the effect of PR on PA. METHODS: This was a prospective study of 29 patients with COPD. They underwent pulmonary rehabilitation twice weekly for 12 weeks, and were assessed using the hospital anxiety and depression score, 6-min walk distance (6MWD), and the St. George Respiratory Questionnaire (SGRQ) before and after they underwent PR. The PA of patients was measured by a three-axis accelerometer. Physical activity level (PAL) was calculated by dividing each patient's total energy expenditure by basal metabolic rate. Correlations between changes in PAL after PR and 6MWD, St. George Respiratory Questionnaire, and hospital anxiety and depression score scores, and clinical parameters, including forced expiratory volume in 1 s were determined. RESULTS: 6MWD was significantly increased, but PAL was unchanged after PR. PAL was positively correlated with 6MWD, but not with percent predicted forced expiratory volume in 1 s nor St. George Respiratory Questionnaire scores before PR. The increase in PAL was negatively correlated with changes in hospital anxiety and depression score anxiety and depression scores, but was not correlated with the change in 6MWD. CONCLUSIONS: A PR program for COPD patients improved results of the 6MWD, but not PAL. Increased PAL was associated with improvements in anxiety and depression, but not with increased exercise capacity. Treating the depression and anxiety of patients with COPD might not only reduce emotional distress, but also improve their PAL. Geriatr Gerontol Int 2017; 17: 17-23.

Fat-free mass index predicts survival in patients with idiopathic pulmonary fibrosis.

BACKGROUND AND OBJECTIVE: Detailed body composition, such as fat-free mass, has not been examined in idiopathic pulmonary fibrosis (IPF). We investigated whether the fat-free mass index (FFMI), an index of lean body mass, predicted survival. METHODS: Forty-four patients with IPF were enrolled in the study. Their body composition was assessed using direct segmental multi-frequency bioelectrical impedance analysis. The degree of correlation between variables of body composition and other variables such as forced vital capacity (FVC) and survival was examined. RESULTS: There was a significant positive correlation between FFMI and FVC, diffusion capacity of the lung for carbon monoxide (DLCO ) and 6-min walk distance, and a significant negative correlation with age. However, there was no significant correlation between FFMI and percentage predicted FVC or DLCO , with the degree of correlation being similar to that observed for BMI. The mean observation period in the survival analysis was 837.5 ± 407.5 days. A univariate Cox proportional hazard model showed that several variables, but not BMI, were associated significantly with survival. FFMI (hazard ratio (HR): 0.64, 95% CI: 0.43-0.94, P = 0.02) and percentage predicted FVC (HR: 0.96, 95% CI: 0.93-0.99, P=0.008) were significant factors in a multivariate model. CONCLUSION: We conclude that FFMI is a significant independent predictor of survival in patients with IPF.

Clinical Features and Outcomes of IPF Patients Hospitalized for Pulmonary Infection: A Japanese Cohort Study.

Many patients with idiopathic pulmonary fibrosis (IPF) undergo hospitalizations due to pulmonary infections. We retrospectively investigated the characteristics of hospitalizations due to pulmonary infection in patients with IPF to elucidate causative pathogens and mortality. We reviewed patients with IPF who were admitted between January 2008 and December 2014 for pulmonary infections including pneumonia and bronchitis. The causative pathogen, the relationship between the site of pneumonia and existing IPF radiological patterns on high-resolution chest CT, and predictors of mortality were evaluated. Forty-eight IPF patients were hospitalized a totally of 81 times due to pulmonary infection during the study period. In the 48 first-time admissions after IPF diagnosis, causative pathogens were detected in 20 patients (41.6%). The most common pathogen was Haemophilus influenzae (14.5%) followed by Pseudomonas aeruginosa (4.1%), Staphylococcus aureus (4.1%), Branhamella catarrhalis (4.1%), and Klebsiella pneumoniae (4.1%). Among all 81 admissions, the most common pathogen was P. aeruginosa (12.3%), followed by H. influenzae (8.6%), S. aureus (6.1%) and Escherichia coli (4.9%). No relationship was observed between the detected pathogen and the site of pneumonia. The 30-day and hospital mortality rates were 14.5% and 18.7%, respectively. Pneumonia severity index on admission was significantly associated with both 30-day and hospital mortality. In conclusion, IPF patients hospitalized for pulmonary infections had high 30-day and hospital mortality. In contrast to community-acquired pneumonia, the causative pathogens mainly consisted of gram-negative bacteria. The PSI score may be a significant predictor of mortality. These results provide information for empiric antibiotic selection when treating IPF patients with pulmonary infections.

Pulmonary Hemodynamics and Six-Minute Walk Test Outcomes in Patients with Interstitial Lung Disease.

Background. Six-minute walk test (6MWT) has 3 measurement outcomes, which are walk distance, desaturation, and symptom. The aim of this study was to examine whether routinely measured right-heart catheter (RHC) data correlate with 6MWT outcomes in patients with interstitial lung disease (ILD). Methods. Between June 2010 and December 2012, consecutive patients with ILD who underwent evaluation, including pulmonary function test, hemodynamic studies with right-heart catheter, and 6MWT as routine general practice, were recruited. Correlates of 3 outcomes of 6MWT were examined to reveal significant predictors. Results. Forty-six patients consisting of 20 with idiopathic pulmonary fibrosis, 14 with collagen vascular disease associated ILD, and 12 with other idiopathic interstitial pneumonia were recruited (mean % predicted FVC: 76.7 ± 17.1%). Several physiological variables, including mean pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR), were correlated with each 6MWT outcome. Stepwise multivariate regression analyses showed that % predicted FVC and % predicted DLco were independent predictors of walk distance (r (2) = 0.35, p = 0.0002). For SpO2 at the end of 6MWT, % predicted DLco and PVR were selected as independent predictors (r (2) = 0.46, p < 0.0001). For dyspnea at the end of 6MWT, % predicted DLco was only one predictor (r (2) = 0.18, p = 0.005). Conclusion. Mean PAP had little impact on 6MWT outcomes in ILD patients who were nonselectively recruited, although PVR was one of predictors of desaturation.