Fernanda Maria Machado Rodrigues

Correlation between heart rate variability indexes and aerobic physiological variables in patients with COPD

Previous studies have shown a relationship between the level of physical fitness and autonomic variables. However, these relationships have not been investigated in patients with chronic obstructive pulmonary disease (COPD). The objective of this study was to correlate the resting heart rate variability (HRV) indexes with aerobic physiological variables obtained at a maximal exercise test in patients with COPD.

Effects of Cigarette Smoking Intensity on the Mucociliary Clearance of Active Smokers

Background: Smoking impairs mucociliary clearance and increases respiratory infection frequency and severity in subjects with and without smoking-related chronic lung diseases. Objective: This study evaluated the effects of smoking intensity on mucociliary clearance in active smokers. Methods: Seventy-five active smokers were grouped into light (1-10 cigarettes/day; n = 14), moderate (11-20 cigarettes/day; n = 34) and heavy smokers (≥21 cigarettes/day; n = 27) before starting a smoking cessation programme. Smoking behaviour, nicotine dependence, pulmonary function, carbon monoxide in exhaled air (exCO), carboxyhaemoglobin (COHb) and mucociliary clearance measured by the saccharin transit time (STT) test were all evaluated. An age-matched non-smoker group (n = 24) was assessed using the same tests. Results: Moderate (49 ± 7 years) and heavy smokers (46 ± 8 years) had higher STT (p = 0.0001), exCO (p < 0.0001) and COHb (p < 0.0001) levels compared with light smokers (51 ± 15 years) and non-smokers (50 ± 11 years). A positive correlation was observed between STT and exCO (r = 0.4; p < 0.0001), STT and cigarettes/day (r = 0.3, p = 0.02) and exCO and cigarettes/day (r = 0.3, p < 0.01). Conclusion: Smoking impairs mucociliary clearance and is associated with cigarette smoking intensity.

Principles of rehabilitation and reactivation.

Skeletal muscle dysfunction and physical inactivity are two clinically important features of a wide range of acute and chronic respiratory conditions. Optimisation of both of these features is important in order to improve physical function, prevent clinical deterioration and maximise community participation. One of the most potent and evidence-based interventions to address these physical deficits is pulmonary rehabilitation (PR). Whilst the majority of PR research has been conducted in patients with chronic obstructive pulmonary disease, there is widespread recognition that PR can benefit many other respiratory patient groups. These include patients with interstitial lung diseases, asthma, pulmonary hypertension, pre-/post-lung surgery (e.g. lung cancer, transplantation) and cystic fibrosis to name a few. Exercise training must be appropriately prescribed by a skilled healthcare professional with comprehensive knowledge of the pathology and physiology of these conditions, as well as a sound understanding of the exercise physiology and core principles of exercise prescription, monitoring and progression. It has also become increasingly recognised that people with respiratory conditions, particularly those with chronic disease, are considerably less active than those of good health. PR should therefore aim to induce behavioural change to facilitate the adoption and maintenance of an active lifestyle. In addition, PR should pay attention to the psychological well-being of patients and self-management of their lung disease in all its aspects. To that end, multidisciplinary individualised programs should be offered. This review sets the scene of PR principles for a series of papers that will focus on specific diseases other than chronic obstructive pulmonary disease where rehabilitation may offer a clinically important aspect of care over and above conventional pharmacological treatment.

Nasal Mucociliary Clearance in Subjects With COPD After Smoking Cessation

BACKGROUND: Exposure to cigarette smoke causes significant impairment in mucociliary clearance (MCC), which predisposes patients to secretion retention and recurrent airway infections that play a role in exacerbations of COPD. To determine whether smoking cessation may influence MCC and frequency of exacerbations, the following groups were evaluated: ex-smokers with COPD, smokers with COPD, current smokers with normal lung function, and nonsmokers with normal lung function. METHODS: Ninety-three subjects were divided into 4 groups: ex-smokers with COPD (n = 23, 62.4 ± 8.0 y, 13 males), smokers with COPD (n = 17, 58.2 ± 8.0 y, 6 males), current smokers (n = 27, 61.5 ± 6.4 y, 17 males), and nonsmokers (n = 26, 60.8 ± 11.3 y, 7 males). MCC was evaluated using the saccharin transit time (STT) test, and the frequency of exacerbations in the last year was assessed by questionnaire. The Kruskal-Wallis test followed by Dunns test were used to compare STT among groups, and the Goodman test was used to compare the frequency of exacerbations. RESULTS: STT of smokers with COPD (16.5 [11–28] min; median [interquartile range 25–75%]) and current smokers (15.9 [10–27] min) was longer compared with ex-smokers with COPD (9.7 [6–12] min) and nonsmokers (8 [6–16] min) (P < .001). There was no difference in STT values between smokers with COPD and current smokers, and these values in ex-smokers with COPD were similar to the control group (P > .05). The frequency of exacerbations was lower in ex-smokers with COPD compared with smokers with COPD. CONCLUSIONS: One year after smoking cessation, subjects with COPD had improved mucociliary clearance.

Analysis of autonomic modulation after an acute session of resistance exercise at different intensities in chronic obstructive pulmonary disease patients

Purpose Physical exercises are employed as part of the treatment of patients with chronic obstructive pulmonary disease (COPD); however information regarding cardiac autonomic modulation after an acute session of resistance exercise (RE) is unknown. The aim of this study was to evaluate the cardiac autonomic modulation, via heart rate variability after an acute session of RE applied at different intensities in COPD patients. Patients and methods Twelve COPD patients underwent an acute session of RE with an intensity of 60% and another of 90% of the one repetition maximum test. For analysis of autonomic modulation, heart rate was recorded beat-by-beat for 20 minutes at rest and after the training session. Heart rate variability indexes were obtained in the time and frequency domains for the assessment of autonomic modulation. Results Regardless of exercise intensity, RE acute sessions influenced the autonomic modulation when the recovery period was compared with the baseline. An increase in standard deviation of normal to normal RR intervals was observed throughout recovery time after the RE, as compared to baseline in both protocols: 60% and 90% of the one repetition maximum test. The spectral component of low frequency index (ms) was higher throughout recovery when compared to baseline in both protocols. The same was also observed in the spectral component of high frequency index (ms) for the protocols of 60% and 90%. Conclusion RE sessions impact on the autonomic modulation of COPD patients by promoting differences in the recovery period compared to baseline, regardless of the intensity of the exercise performed.

Validity and reliability of strain gauge measurement of volitional quadriceps force in patients with COPD

This study investigated the validity and reliability of fixed strain gauge measurements of isometric quadriceps force in patients with chronic obstructive pulmonary disease (COPD). A total cohort of 138 patients with COPD were assessed. To determine validity, maximal volitional quadriceps force was evaluated during isometric maximal voluntary contraction (MVC) manoeuvre via a fixed strain gauge dynamometer and compared to (a) potentiated non-volitional quadriceps force obtained via magnetic stimulation of the femoral nerve (twitch (Tw); n = 92) and (b) volitional computerized dynamometry (Biodex; n = 46) and analysed via correlation coefficients. Test–retest and absolute reliability were determined via calculations of intra-class correlation coefficients (ICCs), smallest real differences (SRDs) and standard errors of measurement (SEMs). For this, MVC recordings in each device were performed across two test sessions separated by a period of 7 days (n = 46). Strain gauge measures of MVC demonstrated very large correlation with Tw and Biodex results (r = 0.86 and 0.88, respectively, both p < 0.0001). ICC, SEM and SRD were numerically comparable between strain gauge and Biodex devices (ICC = 0.96 vs. 0.93; SEM = 8.50 vs. 10.54 N·m and SRD = 23.59 vs. 29.22 N·m, respectively). The results support that strain gauge measures of quadriceps force are valid and reliable in patients with COPD.

Grundlagen der Rehabilitation und Reaktivierung

Eine Dysfunktion der Skelettmuskulatur und Bewegungsmangel sind 2 klinisch bedeutsame Merkmale zahlreicher akuter und chronischer Atemwegserkrankungen. Die Optimierung dieser beiden Faktoren ist sehr wichtig dafür, die körperliche Funktionsfähigkeit zu verbessern, einer klinischen Verschlechterung vorzubeugen und die Teilhabe am Sozialleben zu maximieren. Zu den wirksamsten und am besten belegten Maßnahmen, mit denen diesen physischen Defiziten begegnet wird, zählt die pulmonale Rehabilitation (PR). Der Großteil der Studien zur PR ist zwar bei Patienten mit chronisch-obstruktiver Lungenerkrankung durchgeführt worden, doch es ist weithin anerkannt, dass die PR auch bei vielen anderen Atemwegserkrankungen hilfreich sein kann. Dies gilt beispielsweise für Patienten mit interstitieller Lungenerkrankung, Asthma, pulmonaler Hypertonie, vor/nach einer Lungenoperation (z.B. bei Lungenkarzinom, Transplantation) oder mit Mukoviszidose, um nur einige zu nennen. Ein körperliches Trainingsprogramm muss von kompetentem medizinischem Fachpersonal mit umfassender Kenntnis der Pathologie und Physiologie dieser Krankheiten und fundiertem Verständnis der Sportphysiologie und Grundlagen der Gestaltung, Überwachung und Steigerung eines Bewegungstrainings verordnet werden. Zunehmend wird auch anerkannt, dass Menschen mit - insbesondere chronischen - Atemwegserkrankungen körperlich erheblich weniger aktiv sind als Gesunde. Das Ziel einer PR sollte daher auch sein, Verhaltensumstellungen im Sinne der dauerhaften Annahme eines aktiven Lebensstils herbeizuführen. Außerdem sollte eine PR auch das psychische Wohlbefinden des Patienten und sein Selbstmanagement der Lungenkrankheit in all seinen Facetten berücksichtigen. Dazu sollten individualisierte interdisziplinäre Programme angeboten werden. Die vorliegende Übersichtsarbeit skizziert die Grundlagen der PR als Hintergrund für eine Serie von Artikeln, in denen einzelne Krankheiten behandelt werden, bei denen ähnlich wie bei chronisch-obstruktiver Lungenerkrankung die Rehabilitation einen klinisch bedeutsamen Aspekt der Versorgung über die medikamentöse Therapie hinaus darstellen kann.

Acute Mucociliary Clearance Response to Aerobic Exercise in Smokers

BACKGROUND: Mucociliary clearance is the main defense mechanism of the respiratory system, and it is influenced by several stimuli, including aerobic exercise and cigarette smoking. We evaluated the acute response of mucociliary clearance to aerobic exercise in smokers and nonsmokers compared with that found after acute smoking and smoking combined with exercise. Also, we investigated whether there was a correlation between mucociliary clearance and the autonomic nervous system under these conditions. METHODS: Twenty-one smokers were evaluated for mucociliary clearance by saccharin transit time (STT), and the response of the autonomic nervous system was evaluated by heart rate variability after aerobic exercise, after exercise followed by smoking, after acute smoking, and after rest. For comparison, 17 nonsmokers were also assessed during exercise. Repeated-measures analysis of variance with the Tukey test or the Friedman test followed by the Dunn test was used to evaluate the STT, autonomic response, and other variables to exercise and/or smoking in smokers. A paired t test or Wilcoxon test was used to analyze responses to exercise in nonsmokers. Correlations were evaluated using Pearson or Spearman coefficients. RESULTS: The STT was reduced after exercise in both groups, with similar responses between them. Other stimuli also reduced the STT. The STT showed a negative correlation with sympathetic activity in smokers and a positive correlation with the parasympathetic system in nonsmokers. CONCLUSIONS: Although impaired in smokers, mucociliary clearance responded to the stimulus of exercise, as demonstrated by similar STTs compared with nonsmokers. This response was correlated with the autonomic nervous system in both groups. In smokers, mucociliary clearance also responded to the stimuli of smoking and exercise followed by smoking.

Is dynamometry able to infer the risk of muscle mass loss in patients with COPD

Introduction Sarcopenia is characterized by a progressive and generalized decrease of strength and muscle mass. Muscle mass loss is prevalent in patients with chronic obstructive pulmonary disease (COPD) as a result of both the disease and aging. Some methods have been proposed to assess body composition (and therefore identify muscle mass loss) in this population. Despite the high accuracy of some methods, they require sophisticated and costly equipment. Aim The purpose of this study was to infer the occurrence of muscle mass loss measured by a sophisticated method (dual energy X-ray absorptiometry [DEXA]) using a more simple and affordable equipment (dynamometer). Methods Fifty-seven stable subjects with COPD were evaluated for anthropometric characteristics, lung function, functional exercise capacity, body composition, and peripheral muscle strength. A binary logistic regression model verified whether knee-extension strength (measured by dynamometry) could infer muscle mass loss (from DEXA). Results Patients with decreased knee-extension strength were 5.93 times more likely to have muscle mass loss, regardless of sex, disease stage, and functional exercise capacity (P=0.045). Conclusion Knee-extension dynamometry was able to infer muscle mass loss in patients with COPD.

Evaluation of a 12 Week-Smartphone-based Physical Activity Telecoaching Intervention in Chronic Obstructive Pulmonary Disease: Patient Experiences and Lessons for Implementation. (Preprint)

BACKGROUND Telecoaching approaches can enhance physical activity (PA) in patients with chronic obstructive pulmonary disease (COPD). However, their effectiveness is likely to be influenced by intervention-specific characteristics. OBJECTIVE This study aimed to assess the acceptability, actual usage, and feasibility of a complex PA telecoaching intervention from both patient and coach perspectives and link these to the effectiveness of the intervention. METHODS We conducted a mixed-methods study based on the completers of the intervention group (N=159) included in an (effective) 12-week PA telecoaching intervention. This semiautomated telecoaching intervention consisted of a step counter and a smartphone app. Data from a project-tailored questionnaire (quantitative data) were combined with data from patient interviews and a coach focus group (qualitative data) to investigate patient and coach acceptability, actual usage, and feasibility of the intervention. The degree of actual usage of the smartphone and step counter was also derived from app data. Both actual usage and perception of feasibility were linked to objectively measured change in PA. RESULTS The intervention was well accepted and perceived as feasible by all coaches present in the focus group as well by patients, with 89.3% (142/159) of patients indicating that they enjoyed taking part. Only a minority of patients (8.2%; 13/159) reported that they found it difficult to use the smartphone. Actual usage of the step counter was excellent, with patients wearing it for a median (25th-75th percentiles) of 6.3 (5.8-6.8) days per week, which did not change over time (P=.98). The smartphone interface was used less frequently and actual usage of all daily tasks decreased significantly over time (P<.001). Patients needing more contact time had a smaller increase in PA, with mean (SD) of +193 (SD 2375) steps per day, +907 (SD 2306) steps per day, and +1489 (SD 2310) steps per day in high, medium, and low contact time groups, respectively; P for-trend=.01. The overall actual usage of the different components of the intervention was not associated with change in step count in the total group (P=.63). CONCLUSIONS The 12-week semiautomated PA telecoaching intervention was well accepted and feasible for patients with COPD and their coaches. The actual usage of the step counter was excellent, whereas actual usage of the smartphone tasks was lower and decreased over time. Patients who required more contact experienced less PA benefits. TRIAL REGISTRATION ClinicalTrials.gov NCT02158065; http://clinicaltrials.gov/ct2/show/NCT02158065 (Archived by WebCite at http://www.webcitation.org/73bsaudy9).