Knowledge and perceptions regarding pulmonary rehabilitation amongst Ecuadorian physicians following COVID-19 outbreak

Background

Pulmonary rehabilitation is already an established technique for patients with chronic respiratory disease, aimed at improving breathlessness, exercise capacity, health status, and well-being. The aim of this study was to assess the knowledge and perceptions about pulmonary rehabilitation post-COVID-19 infection among Ecuadorian physicians.

Methods

We conducted a cross-sectional online survey-based study using a 27-item questionnaire to assess the knowledge about specific topics related to pulmonary rehabilitation. The sample comprised Ecuadorian physicians who were currently enrolled to an active medical practice that included care to COVID-19 patients. Descriptive statistics were applied for demographic variables of interest. A chi-square goodness of fit test was used to determine whether the observed frequencies of each of the answers per query were within or outside of the expected frequencies by chance.

Results

In total, 295 participants answered the survey, out of which 57.3% were general practitioners. Most agreed that COVID-19 infected patients must be followed-up with some measurement of respiratory function (81.4%, p=0.000), but only 18.3% (n=54, p=0.000) were aware of specific guidelines related to rehabilitation. 93.6% (n=276, p=0.000) considered that pulmonary rehabilitation provides a benefit, of any kind, to patients with past COVID-19 infection.

Conclusions

Most physicians considered pulmonary rehabilitation beneficial following COVID-19. However, there is uncertainty on how to adequately follow up patients, complementary tests, and specific guidelines outlining rehabilitative interventions.

Residual pulmonary infiltrates, symptoms and diffusion impairment at one-year after severe COVID-19 infection have different associated factors

INTRODUCTION

After severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia, patients may show lung sequelae on radiology and functional impairment at the 1-year follow-up. We aimed to describe the persistence of symptoms, radiological alterations, or reduced diffusing capacity of the lung for carbon monoxide (D_LCO ) at 1-year follow-up in patients from the Spanish Registry RECOVID.

METHODS

RECOVID collected symptom and radiological and functional lung tests data on hospitalised patients with coronavirus disease 2019 during the acute phase and at the 6- and 12-month follow-up visits.

RESULTS

Of the 2500 enrolled survivors (90% admitted to the ward), 1874 had follow-up visits for up to a year. Of these, 42% continued to present with symptoms, 27% had radiological sequelae, and 31% had reduced D_LCO . Independently associated factors included female sex, asthma, and the requirement for invasive or non-invasive mechanical ventilation. Complete radiological resolution was 72.2% at 12 months; associated factors with incomplete recovery were age, male sex, oxygen or respiratory support, corticosteroids and an initial SpO₂ /FiO₂ <450 or CURB65 ≥2. Reduced D_LCO was observed in 31% of patients at 12 months; associated factors were older age, female sex, smoking habit, SpO₂ /FiO₂ <450 and CURB-65 ≥2, and the requirement of respiratory support. At 12 months, a proportion of the asymptomatic patients showed reduced D_LCO (9.5%), radiological findings (25%), or both (11%).

CONCLUSIONS

The factors associated with symptom persistence, incomplete radiological resolution, and D_LCO <80% differed according to age, sex, comorbidities, and respiratory support. The burden of symptoms, reduced D_LCO , and incomplete radiological resolution were considerable in patients with SARS-CoV-2 pneumonia at the 1-year follow-up after hospitalisation. This article is protected by copyright. All rights reserved.

Impact of high-flow oxygen therapy during exercise in idiopathic pulmonary fibrosis: a pilot crossover clinical trial

BACKGROUND

Supplemental oxygen delivered with standard oxygen therapy (SOT) improves exercise capacity in patients with idiopathic pulmonary fibrosis (IPF). Although high-flow nasal cannula oxygen therapy (HFNC) improves oxygenation in other respiratory diseases, its impact on exercise performance has never been evaluated in IPF patients. We hypothesized that HFNC may improve exercise capacity in IPF subjects compared to SOT.

METHODS

This was a prospective, crossover, pilot randomized trial that compared both oxygenation methods during a constant submaximal cardiopulmonary exercise test (CPET) in IPF patients with exertional oxygen saturation (SpO₂) ≤ 85% in the 6-min walking test. The primary outcome was endurance time (Tlim). Secondary outcomes were muscle oxygen saturation (StO₂) and respiratory and leg symptoms.

RESULTS

Ten IPF patients [71.7 (6) years old, 90% males] were included. FVC and DL_CO were 58 ± 11% and 31 ± 13% pred. respectively. Tlim during CPET was significantly greater using HFNC compared to SOT [494 ± 173 vs. 381 ± 137 s, p = 0.01]. HFNC also associated with a higher increase in inspiratory capacity (IC) [19.4 ± 14.2 vs. 7.1 ± 8.9%, respectively; p = 0.04], and a similar trend was observed in StO₂ during exercise. No differences were found in respiratory or leg symptoms between the two oxygen devices.

CONCLUSIONS

This is the first study demonstrating that HFNC oxygen therapy improves exercise tolerance better than SOT in IPF patients with exertional desaturation. This might be explained by changes in ventilatory mechanics and muscle oxygenation. Further and larger studies are needed to confirm the benefits of HFNC in IPF patients and its potential usefulness in rehabilitation programs.

Pulmonary valve replacement in women with repaired tetralogy of Fallot. Contrasting indications compared with men

Background

Recent data suggest that in pulmonary regurgitation (PR) after repair of Tetralogy of Fallot (rToF) sex may influence right ventricular (RV) size, mass and function. We hypothesized that women with rToF and PR constitute a patient population with different preoperative clinical characteristics and different postoperative outcomes compared with men.

Methods

We collected retrospectively demographic data, clinical variables, imaging and functional variables in a cohort of 166 rToF patients (50% males; median age 35; IQR 26–41 years) with at least moderate PR. A transannular patch was used in 73 and 79% of men and women, respectively. The most recent data preceding death and pulmonary valve replacement (PVR) were requested. Variables were compared between men and women.

Results

Over follow-up, none of the patients died but 35 (42.7%) men and 23 (27.4%) women underwent PVR (p=0.05) at a median age of 32.5 (IQR 23.7–42.7 years). Women are more likely to undergo surgery after developing symptoms, while the criterion for surgery in men was ventricular size. At surgery, women were nearly twice as likely to have class III or IV symptoms preoperatively as men. Although PR fraction was similar between the two groups, indexed ventricular volumes were substantially higher and RV function was lower in males, compared to females. 20% of women had a RVEDVi ≥160ml and a RVESVi ≥80ml, compared with 35 and 32% of men, respectively (p=0.06), and only 6% of woman had an RVEDVi &gt;180ml, compared with 18% of men (p=0.01). Fibrosis detected on late gadolinium was observed in 100% of men but only in 20% of women (p=0.009).

Conclusions

Under comparable loading conditions, a striking difference was noted in the condition leading to the surgical indication. These results suggest that the generalization of the RV dimension surgical criteria results in criteria almost never reached by women. Recommendations need more focus on sex differences.

Funding Acknowledgement

Type of funding sources: None.

Telerehabilitation Programme as a Maintenance Strategy for COPD Patients: A 12-Month Randomized Clinical Trial

BACKGROUND

There is uncertainty regarding efficacy of telehealth-based approaches in COPD patients for sustaining benefits achieved with intensive pulmonary rehabilitation (PR).

RESEARCH QUESTION

To determine whether a maintenance pulmonary telerehabilitation (TelePR) programme, after intensive initial PR, is superior to usual care in sustaining over time benefits achieved by intensive PR.

STUDY DESIGN AND METHODS

A multicentre open-label pragmatic parallel-group randomized clinical trial was conducted. Two groups were created at completion of an 8-week intensive outpatient hospital PR programme. Intervention group (IG) patients were given appropriate training equipment and instructed to perform three weekly training sessions and send performance data through an app to a web-based platform. Patients in the control group (CG) were advised to exercise regularly (usual care).

RESULTS

Ninety-four patients (46 IG, 48 CG) were randomized. The analysis of covariance showed non-significant improvements in 6-min walk distance [19.9m (95% CI -4.1/+43.8)] and Chronic Respiratory Disease Questionnaire - Emotion score [0.4 points (0-0.8)] in the IG. Secondary linear mixed models showed improvements in the IG in Short Form-36 mental component summary [9.7, (4.0-15.4)] and Chronic Respiratory Disease Questionnaire - Emotion [0.5, (0.2-0.9)] scores, but there was no association between compliance and outcomes. Acute exacerbations were associated with a marginally significant decrease in 6-minute walk distance of 15.8m (-32.3/0.8) in linear models.

CONCLUSIONS

The TelePR maintenance strategy was both feasible and safe but failed to show superiority over usual care, despite improvements in some HRQoL domains. Acute exacerbations may have an important negative influence on long-term physical function. CLINICALTRIALS.

GOV IDENTIFIER

NCT03247933.

Benefits of Long-Term Pulmonary Rehabilitation Maintenance Program in Patients with Severe Chronic Obstructive Pulmonary Disease. Three-Year Follow-up

RATIONALE

In chronic obstructive pulmonary disease (COPD), the benefits of pulmonary rehabilitation (PR) tend to wane over time. Whether maintenance techniques may help sustain the benefits achieved after completion of the initial PR program remains controversial.

OBJECTIVES

To determine whether a long-term (3-yr) maintenance program after PR preserves the short-term effects on outcomes in patients with COPD.

METHODS

This was a multicenter prospective randomized trial including 143 patients with moderate-severe COPD, with 3 years of PR maintenance following an 8-week outpatient PR program. Patients were randomized to maintenance intervention group (IG) and standard monitoring program or control group (CG). The effects on BODE index, 6-minute-walk test distance (6MWD), and health-related quality of life were compared at 12, 24, and 36 months.

MEASUREMENTS AND MAIN RESULTS

A total of 138 (96.5%) completed the 8-week program. At this time, all outcomes (BODE, 6MWD, and health-related quality of life) showed clinically and statistically significant improvements (P ≤ 0.001). During the follow-up period, the magnitude of change in 6MWD differed between IG and CG (P = 0.042), with a slight initial increase in the IG during the first year and smaller decline afterward. The BODE index changes differed between baseline and measurements at Month 24 (P = 0.043). At 3 years, the adherence rate of IG patients was 66% and 17% for the CG group (P < 0.001).

CONCLUSIONS

This study shows a 2-year beneficial effect of a program of rehabilitation maintenance on the BODE index and 6MWD when compared with a standard strategy. This effect vanishes after the second year of follow-up. Clinical trial registered with www.clinicaltrials.gov (NCT 01090999).

The role of daily physical activity and nutritional status on bone turnover in cystic fibrosis: a cross-sectional study

BACKGROUND

Nutritional status and daily physical activity (PA) may be an excellent tool for the maintenance of bone health in patients with cystic fibrosis (CF).

OBJECTIVE

To evaluate the relationship between nutritional status, daily physical activity and bone turnover in cystic fibrosis patients.

METHOD

A cross-sectional study of adolescent and adult patients diagnosed with clinically stable cystic fibrosis was conducted. Total body, femoral neck, and lumbar spine bone mineral density (BMD) were determined by dual energy X-ray absorptiometry and bone metabolism markers ALP, P1NP, PICP, and ß-CrossLaps. PA monitoring was assessed for 5 consecutive days using a portable device. Exercise capacity was also determined. Serum 25-hydroxyvitamin D and vitamin K were also determined in all participants.

RESULTS

Fifty patients (median age: 24.4 years; range: 16-46) were included. BMI had positive correlation with all BMD parameters, with Spearman's coefficients ranging from 0.31 to 0.47. Total hip bone mineral density and femoral neck BMD had positive correlation with the daily time spent on moderate PA (>4.8 metabolic equivalent-minutes/day; r=0.74, p<0.001 and r=0.72 p<0.001 respectively), daily time spent on vigorous PA (>7.2 metabolic equivalent-minutes/day; r=0.45 p<0.001), body mass index (r=0.44, p=0.001), and muscle mass in limbs (r=0.41, p=0.004). Levels of carboxy-terminal propeptide of type 1 collagen were positively associated with the daily time spent on moderate (r=0.33 p=0.023) and vigorous PA (r=0.53, p<0.001).

CONCLUSIONS

BMI and the daily time spent on moderate PA were found to be correlated with femoral neck BMD in CF patients. The association between daily PA and biochemical markers of bone formation suggests that the level of daily PA may be linked to bone health in this patient group. Further research is needed to confirm these findings.

Guidelines for the evaluation and treatment of muscle dysfunction in patients with chronic obstructive pulmonary disease

In patients with chronic obstructive pulmonary disease (COPD), skeletal muscle dysfunction is a major comorbidity that negatively impacts their exercise capacity and quality of life. In the current guidelines, the most recent literature on the various aspects of COPD muscle dysfunction has been included. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) scale has been used to make evidence-based recommendations on the different features. Compared to a control population, one third of COPD patients exhibited a 25% decline in quadriceps muscle strength, even at early stages of their disease. Although both respiratory and limb muscles are altered, the latter are usually more severely affected. Numerous factors and biological mechanisms are involved in the etiology of COPD muscle dysfunction. Several tests are proposed in order to diagnose and evaluate the degree of muscle dysfunction of both respiratory and limb muscles (peripheral), as well as to identify the patients' exercise capacity (six-minute walking test and cycloergometry). Currently available therapeutic strategies including the different training modalities and pharmacological and nutritional support are also described.

Pulmonary rehabilitation. Sociedad Española de Neumología y Cirugía Torácica (SEPAR)

Pulmonary rehabilitation (PR) has been shown to improve dyspnea, exercise capacity and health-related quality of life in patients with chronic obstructive pulmonary disease (COPD). PR has also shown benefits in diseases other than COPD but the level of evidence is lower. The fundamental components of PR programs are muscle training, education and chest physiotherapy. Occupational therapy, psychosocial support and nutritional intervention should also be considered. Home programs have been shown to be as effective as hospital therapy. The duration of rehabilitation programs should not be less than 8 weeks or 20 sessions. Early initiation of PR, even during exacerbations, has proven safe and effective. The use of oxygen or noninvasive ventilation during training is controversial and dependent on the patient's situation. At present, the best strategy for maintaining the benefits of PR in the long term is unknown. Longer PR programs or telemedicine could play a key role in extending the results obtained.

Exercise training in patients with chronic respiratory failure due to kyphoscoliosis: a randomized controlled trial

BACKGROUND

Research has provided evidence for the safety, feasibility, and efficacy of exercise training in patients with COPD. However, little is known about the impact of exercise training in patients with chronic respiratory failure due to kyphoscoliosis. We evaluated the effect of an exercise training program on exercise capacity, muscle strength, dyspnea, and quality-of-life indices in subjects with chronic respiratory failure due to kyphoscoliosis.

METHODS

The 34 subjects were clinically stable, had been receiving nighttime home mechanical ventilation for ≥ 6 months, and were randomly assigned to the exercise group (n = 17) or the control group (n = 17). The exercise group conducted cycle and strength training on 3 non-consecutive days per week for 12 weeks. We measured pulmonary function, exercise capacity, peripheral muscle strength, dyspnea scores, and quality of life.

RESULTS

Statistical analysis was carried out on the data from 16 subjects in the exercise group and in 11 subjects in the control group. Three of the lung-function parameters in the exercise group significantly changed: PaCO2 (P = .04), inspiratory pressure (P = .03), and expiratory pressure (P = .04); and endurance time (P = .002) and shuttle walk distance (P = .001) increased significantly. The exercise group had significantly greater improvements in peripheral muscle strength, dyspnea, and quality of life.

CONCLUSIONS

In patients with chronic respiratory failure due to kyphoscoliosis, exercise training improved exercise capacity, peripheral muscle strength, dyspnea, and quality of life. (Deutschen Register Klinischer Studien DRKS00000443).

Impact of bronchodilator responsiveness on quality of life and exercise capacity in patients with COPD

BACKGROUND

Bronchial variability in COPD patients may be a phenotypic feature associated with clinical characteristics and differential treatment response. We analyzed whether symptoms, quality of life, and exercise capacity varied in COPD patients as a function of bronchodilator test results, and compared responses to an exercise program.

METHODS

A positive bronchodilator test result was defined as FVC and/or FEV1 improvement of > 12% plus > 200 mL after 400 μg of salbutamol. We studied 198 COPD subjects: 94 with positive reversibility, and 104 with negative reversibility. Training sessions were carried out on 3 non-consecutive days each week, for 12 weeks, and consisted of a combination of resistance and strength training. Subjects were evaluated on 2 consecutive days at baseline, and at the end of the 12-week training program.

RESULTS

Those with positive reversibility had shorter time to exhaustion in the endurance test (19.1 ± 12.6 min vs 24.5 ± 14.5 min, P = .03), shorter shuttle walk test distance (380.6 ± 158.2 m vs 438.5 ± 149.1 m, P = .02), and lower Chronic Respiratory Disease Questionnaire scores (18.7 ± 4.6 vs 19.8 ± 4.3, P = .01). There were no significant differences in peak exercise, peripheral muscle strength, dyspnea, or improvement after exercise training.

CONCLUSIONS

Compared to COPD subjects with negative reversibility, those with positive reversibility walked for shorter distances, and had shorter endurance times and worse quality of life, but the improvements after exercise training were similar.

Determination of inflammatory biomarkers in patients with COPD: a comparison of different assays

Background

Chronic obstructive pulmonary disease (COPD) is an inflammatory pulmonary disorder with systemic inflammatory manifestations that are mediated by circulating acute-phase reactants. This study compared an enzyme-linked immunosorbent assay (ELISA) to a nephelometric technique for the measurement of serum C-reactive protein (CRP) and serum amyloid A (SAA) and investigated how the choice of assay influenced the estimation of inflammation in patients with stable COPD.

Methods

CRP and SAA concentrations measured by ELISA and nephelometry in 88 patients with COPD and 45 control subjects were used to evaluate the performance of these methods in a clinical setting.

Results

With both assays, the concentrations of CRP and SAA were higher in COPD patients than in controls after adjustment for age and sex. There was a moderate correlation between the values measured by ELISA and those measured by nephelometry (logCRP: r = 0.55, p < 0.001; logSAA: r = 0.40, p < 0.001). However, the concentrations of biomarkers determined by nephelometry were significantly higher than those obtained with ELISA for CRP (mean difference = 2.7 (9.4) mg/L) and SAA (mean difference = 0.31 (14.3) mg/L).

Conclusion

Although the serum CRP and SAA concentrations measured by ELISA and nephelometry correlated well in COPD patients, the ELISA values tended to be lower for CRP and SAA when compared with nephelometric measurements. International standardization of commercial kits is required before the predictive validity of inflammatory markers for patients with COPD can be effectively assessed in clinical practice.

Cyclooxygenase-2 -765G>C polymorphism is associated with C-reactive protein levels in resistant smokers but not in chronic obstructive pulmonary disease patients

We sought to investigate whether the serum concentrations of several inflammatory biomarkers are related to the cyclooxygenase-2 (COX2) -765G>C polymorphism in chronic obstructive pulmonary disease (COPD) and a control group of non-COPD smokers. Serum inflammatory markers (CRP, SAA, CXCL8, and sICAM-1) were measured by ELISA in 144 patients with COPD and in 55 control subjects. Genomic DNA was extracted from peripheral blood leukocytes, and the COX2 -765G>C (rs20417) polymorphism was genotyped. After adjustment for age and active smoking, CRP and SAA concentrations were associated with the COX2 polymorphism in controls (p=0.041 and 0.014, respectively) but not in COPD patients. The CXCL8 and sICAM-1 concentrations were not associated with the COX2 polymorphism for either cases or controls. The results of the present study indicate that there is a relationship between the COX2 -765G>C polymorphism and the concentrations of CRP and SAA in non-COPD smokers and that this relationship does not exist in COPD patients.

Overexpression of Aquaporin-1 in lung adenocarcinomas and pleural mesotheliomas

Aquaporin-1 (AQP1) is the main water channel responsible for water transport through many epithelia and endothelia. The latest evidence pointed toward an important role of this protein also in gas permeation, angiogenesis, cell proliferation and migration. In the present work we studied the expression of AQP1 by immunohistochemical staining of 92 lung biopsies from patients diagnosed with a pleuro-pulmonary tumor (71 lung and 21 pleural neoplasms). AQP1 expression was analyzed comparing the results among the different histological patterns and against 9 control cases (5 parenchyma and 4 healthy pleura). Clear staining of AQP1 was detected in 39 of the 92 tumors analyzed. In parenchyma, AQP1 was more frequently detected in primary lung adenocarcinomas (55%, P<0.001); in contrast, small cell carcinomas were the least AQP1 expressive tumors studied (93% of negative staining, P<0.05). Carcinomas analyzed in pleura (mesotheliomas and metastatic adenocarcinomas) also revealed strong expression of AQP1. High expression of this protein was detected in small capillaries in areas near or surrounding the tumor, and novel intense AQP1 immunostaining was detected over thicker alveolar walls in alveoli inside or next to the tumoral tissue regardless of the tumor type. An important role of AQP1 in tumor angiogenesis is sustained by the abundant expression of this protein in the endothelia of tumor capillaries. Further studies are necessary to elucidate the potential pathophysiological role of this protein in pleuro-pulmonary neoplasms.

Effectiveness of a cognitive orientation program with and without nicotine replacement therapy in stopping smoking in hospitalised patients

INTRODUCTION

We analysed the effectiveness of a high intensity behavioural-cognitive intervention compared to minimal intervention started during a hospital stay, to see if the combination of nicotine replacement therapy (NRT) can increase the quitting rate at 12 months of follow up.

METHOD

A total of 2560 active smokers were studied during their hospital stay. Of these, 717 smokers refused to enter the study and after a minimal intervention they were asked if we could telephone them after one year to ask if they still smoked. The remaining 1843 smokers who received high intensity cognitive therapy were randomised to receive or not receive NRT. The follow up after discharge was carried out by outpatient visits or with telephone sessions.

RESULTS

At one year of follow up, 7% of those who declined to enter the study had stopped smoking compared to 27% of those who entered the study (p<0.001). There were significant differences between the group that only had behavioural therapy (21% stopped) compared to the group that also had NRT (33% stopped; p=0.002). In this latter group there were significant differences (p=0.03) between those who had follow up in clinics (39% stopped) compared to those who were followed up telephone sessions (30%). In the multivariate analysis, the predictors of quitting at 12 months were: to have used NRT (OR 12.2; 95% CI, 5.2-32; p=0.002) and a higher score in the Richmond Test (OR 10.1; 95% CI, 3.9-24.2; p=0.01).

CONCLUSIONS

A cognitive type intervention started on smokers when admitted to hospital increases quitting rates at 12 months, compared to a minimal intervention, and these rates increase even more significantly if NRT is added.

Factors associated with quality of life in patients with chronic respiratory failure due to kyphoscoliosis

OBJECTIVES

Patients with chronic respiratory failure due to kyphoscoliosis (CHRF-KS) constitute a specific population with impaired health-related quality of life (HRQL). Thus far, no studies have examined factors related to HRQL. The objective of the present study was to identify clinical, functional and exertion-related factors associated with HRQL.

METHODS

We investigated 27 patients (12 males). Respiratory function tests, dyspnea ratings, peripheral and respiratory muscle function and exercise testing were performed. The Chronic Respiratory Disease Questionnaire (CRDQ) was used to assess HRQL. Bivariate correlations were used to investigate the relationships between CRDQ dimensions and the clinical, functional and exertion-related characteristics of the study participants.

RESULTS

The general characteristics of the study sample were as follows: age: 61 (IQR: 12) years, FVC: 32.6% (IQR: 10.2) and pCO2: 48 mmHg (IQR: 8.7). Peripheral muscle strength, dyspnea and exercise capacity were identified as significant factors associated with poorer HRQL. The CRDQ dimensions of fatigue and emotional function showed greater correlations with the patients' general characteristics. Dyspnea CRDQ scores did not correlate with dyspnea in any of the scales used.

CONCLUSION

Of the various factors examined, dyspnea, exercise capacity and peripheral muscle strength have been identified as significant factors associated with HRQL in CHRF-KS patients.

Shuttle walking versus maximal cycle testing: clinical correlates in patients with kyphoscoliosis

A cross-sectional prospective design was used to compare the effectiveness of the shuttle walking test (SWT) and the maximal cycle ergometry test (CET) to assess the functional capacity of patients with chronic hypercapnic respiratory failure due to severe kyphoscoliosis. Twenty-four patients completed both the SWT and CET. Heart rate, blood pressure, leg fatigue, chest pain and dyspnea (Borg's scale) were measured immediately after each test. Correlation coefficients and Bland-Altman analysis were used to compare the two methods. Borg's dyspnea, leg and chest pain after exercise were not significantly different between tests. Only heart rate (SWT 130[20.7] versus CET 116[28.75]; p = 0.048) and diastolic blood pressure (SWT: 85.5[13.75] versus CET 95[17.5]; p = 0.021) were slightly but significantly different between the two protocols. There was a good positive correlation between the distance walked in SWT and maximal oxygen consumption (r = 0.675; p < 0.001). SWT and CET testing elicited similar clinical and hemodynamic responses. SWT is a feasible measure of functional capacity in this patient group.

Exercise training in mitochondrial myopathy: A randomized controlled trial

Patients with mitochondrial myopathies (MM) usually suffer from exercise intolerance due to their impaired oxidative capacity and physical deconditioning. We evaluated the effects of a 12-week supervised randomized rehabilitation program involving endurance training in patients with MM. Twenty MM patients were assigned to a training or control group. For three nonconsecutive days each week, patients combined cycle exercise at 70% of their peak work rate with three upper-body weight-lifting exercises performed at 50% of maximum capacity. Training increased maximal oxygen uptake (28.5%), work output (15.5%), and minute ventilation (40%), endurance performance (62%), walking distance in shuttle walking test (+95 m), and peripheral muscle strength (32%-62%), and improved Nottingham Health Profile scores (21.47%) and clinical symptoms. Control MM patients did not change from baseline. Results show that our exercise program is an adequate training strategy for patients with mitochondrial myopathy.

Comparison of effects of strength and endurance training in patients with chronic obstructive pulmonary disease

We determined the effect of different exercise training modalities in patients with chronic obstructive pulmonary disease, including strength training (n = 17), endurance training (n = 16), and combined strength and endurance (n = 14) (half of the endurance and half of the strengthening exercises). Data were compared at baseline, the end of the 12-week exercise-training program, and 12 weeks later. Improvement in the walking distance was only significant in the strength group. Increases in submaximal exercise capacity for the endurance group were significantly higher than those observed in the strength group but were of similar magnitude than those in the combined training modality, which in turn were significantly higher than for the strength group. Increases in the strength of the muscle groups measured in five weight lifting exercises were significantly higher in the strength group than in the endurance group but were of similar magnitude than in the combined training group, which again showed significantly higher increases than subjects in the endurance group. Any training modality showed significant improvements of the breathlessness score and the dyspnea dimension of the chronic respiratory questionnaire. In conclusion, the combination of strength and endurance training seems an adequate training strategy for chronic obstructive pulmonary disease patients.

Human hepatic stellate cells secrete adrenomedullin: potential autocrine factor in the regulation of cell contractility

BACKGROUND/AIMS

Hepatic stellate cells (HSCs) are perisinusoidal pericytes which have receptors for vasoactive factors, such as endothelin-1, which can regulate cell contractility in an autocrine manner. It is unknown whether human HSCs have receptors for and are able to synthesize the vasodilator peptide adrenomedullin (ADM), a peptide produced by most contractile cells.

METHODS AND RESULTS

Stimulation of HSCs with ADM resulted in a dose-dependent raise in cAMP concentration (radioimmunoassay) and markedly blunted the endothelin-induced increase in [Ca2+]i and cell contraction, as assessed in cells loaded with fura-2 using a morphometric method. The existence of the receptor CRLR for ADM and their associated proteins RAMP-1 and RAMP-2 was demonstrated by reverse transcriptase-polymerase chain reaction (RT-PCR). Moreover, activated human HSCs spontaneously secreted ADM in the culture medium in a time-dependent manner. ADM secretion was markedly enhanced by tumour necrosis factor-alpha and interleukin-1beta. Specific mRNA for ADM (RT-PCR and Northern blot) was detected in HSCs and increased after incubation of cells with cytokines.

CONCLUSIONS

Human HSCs have functional receptors for ADM, the stimulation of which blunts the contractile effect of endothelin-1. Cultured human HSCs secrete ADM in baseline conditions. This secretion is markedly increased by cytokines. These results suggest that ADM can regulate HSCs' contractility in an autocrine manner.

Long-term aquaretic efficacy of a selective nonpeptide V(2)-vasopressin receptor antagonist, SR121463, in cirrhotic rats

Water retention in experimental cirrhosis can be reversed by blocking V(2)-vasopressin (AVP) receptors with the nonpeptide antagonist OPC-31260 or by using the kappa-opioid receptor agonist niravoline, a compound inhibiting central AVP release. However, reluctance to use these drugs in human beings has emerged because the former loses aquaretic efficacy in rats after 2 days of treatment and the latter may have adverse effects in humans. Recently, a new potent and selective nonpeptide V(2)-AVP receptor antagonist, SR121463, has been developed that could be useful for the treatment of dilutional hyponatremia in human cirrhosis. The current study assessed the aquaretic efficacy of 10-day chronic oral administration of SR121463 (0.5 mg/kg/day) in cirrhotic rats with ascites and impaired water excretion after a water load (minimum urinary osmolality >160 mOsm/kg and percentage of water load excreted <60%). Urine volume (UV), osmolality (U(Osm)V), and sodium excretion (U(Na)V) were measured daily. At the end of the 10-day treatment, mean arterial pressure also was measured. In basal conditions cirrhotic rats showed ascites, sodium retention, and impaired water excretion. UV, U(Osm)V, and U(Na)V did not change throughout the study in cirrhotic rats receiving the vehicle. In contrast, SR121463 increased UV and reduced U(Osm)V during the 10-day treatment. This resulted in a greater renal ability to excrete a water load and normalization in serum sodium and osmolality. During the first 6 days of treatment, SR121463 also increased U(Na)V without affecting mean arterial pressure. These data suggest that SR121463 could be of therapeutical value for chronic management of human cirrhosis.

Vascular endothelial growth factor production in peritoneal macrophages of cirrhotic patients: regulation by cytokines and bacterial lipopolysaccharide

Vascular endothelial growth factor (VEGF) is an angiogenic peptide with vascular permeability and relaxing properties. This study assessed whether peritoneal macrophages of cirrhotic patients can be up-regulated to produce VEGF under proper stimulatory conditions. Macrophages were isolated from ascites. VEGF protein secretion and mRNA expression were measured in basal conditions and after stimulation with lipopolysaccharide (LPS), tumor necrosis factor alpha (TNF-alpha), and interleukin-1 (IL-1). These substances induced a time- and dose-dependent increase in both VEGF production and transcript expression. Assays with actinomycin D showed that VEGF mRNA induction is secondary to both higher VEGF gene transcription and mRNA stability. Ascites and plasma concentration of VEGF was also measured in cirrhotic patients with (n = 15) and without (n = 10) spontaneous bacterial peritonitis (SBP). Plasma values did not differ between both groups of patients. However, ascites VEGF levels were higher in SBP patients than in noninfected cirrhotic patients (710 +/- 183 vs. 94 +/- 15 pg/mL; P <.025). These results indicate that cytokines and LPS markedly increase VEGF protein secretion and mRNA expression in macrophages of cirrhotic patients, and suggest that this substance could be an important mediator of the pronounced arterial vasodilation frequently occurring in SBP patients.

[Peripheral muscle strength in stable COPD patients: correlation with respiratory function variables and quality of life]

The aim of this study was to assess peripheral muscle strength in patients with chronic obstructive pulmonary disease (COPD) using a simple test and to look for correlation with function variables, physiological strength variables and quality of life parameters. Twenty-three COPD patients with moderate to severe air-flow limitation (FEV1 = 39 +/- 12%) in stable phase but displaying inability to carry out daily tasks were enrolled. Peripheral muscle strength was assessed in all patients by measuring the maximum load in a single repetition of five simple upper and lower extremity exercises performed at a multi-gymnastics station. Results were compared to respiratory function variables (FVC, FEV1, FEV1/FVC and gasometry), to results of an exercise test on a cycle ergometer with monitoring of respiratory gases (VEmax, VO2max and Wmax), to endurance (minutes) to dyspnea (Mahler's scale) and to quality of life (Chronic Respiratory Disease Questionnaire-CRDQ). No relation between functional parameters and endurance in minutes was found. Minute ventilation (VE) proved to be significantly related to oxygen intake (VO) and maximum work in the stress test. Dyspnea on Mahler's scale was unrelated, but fatigue variables and emotional function variables on the CRDQ were related. We conclude that peripheral muscle strength is unrelated to level of flow limitation or exercise tolerance in COPD patients. Peripheral muscle strength is related, however, to maximum work load and some aspects of quality of life.

[Efficacy of a program for tobacco use cessation with a combined substitution treatment of nicotine (patches plus chewing gum) at 6 months of follow-up]

Our aim was to assess the efficacy after 6 months of combined smoking cessation therapy using nicotine substitution with both chewing gum and patches. Sixty-six (25 women, 41 men) heavy smokers (38.04 packs/year and 8.42 mean score on Fagerström test) were followed between September 1995 and March 1997. Most patients were referred by respiratory, cardiology or ear-nose-and-throat outpatient clinics. The patients were prescribed 24-hour nicotine substitution therapy with 21 mg patches, plus chewing gum providing 2 mg of nicotine (3 to 10 per day) for a minimum of 8 weeks and a maximum of 12, with gradually decreasing doses. The patients were checked 1, 2, 4, 8, 12 and 24 weeks after enrollment. Expired air carbon monoxide was measured to confirm abstinence at each checkup and a simple questionnaire was filled in to assess abstinence syndrome and detect the presence of treatment side effects. Rate of abstinence achieved with this protocol after six months of follow-up was 37.9%. The failure rate was highest in the first week (33%) but gradually decreased until week 12. No patients had to abandon treatment due to side effects.