Disfunción autonómica en pacientes con enfermedad pulmonar obstructiva crónica: efectos del entrenamiento sobre la recuperación de la frecuencia cardiaca / Autonomic dysfunction in patients with chronic obstructive pulmonary disease: Effects of training on heart rate recovery

Introducción: La recuperación de la frecuencia cardíaca (RFC) tras un esfuerzo máximo es un índice de función autonómica y se asocia con mayor mortalidad en algunas patologías. El objetivo de este estudio fue evaluar la prevalencia de disfunción autonómica en pacientes con enfermedad pulmonar obstructiva crónica (EPOC) estable y sus eventuales cambios con un programa de rehabilitación pulmonar. Pacientes y métodos: Estudio transversal de 68 pacientes con EPOC en fase estable (edad media: 71 años [DE: 8]), 65 hombres y 3 mujeres, volumen espiratorio forzado en el primer segundo (%) medio: 36,8 (DE: 11,9), incluidos en programa de entrenamiento aeróbico y de fuerza y resistencia (25 sesiones). Se realizó prueba de esfuerzo cardiopulmonar (PECP), prerrehabilitación en todos los pacientes. En un subgrupo de 12 se realizó, además, PECP posrehabilitación. Se evaluó la RFC en valores absolutos y categorizada tras claudicación en la PECP respecto a la frecuencia cardíaca pico (normalidad RFC>12). Resultados: Hubo 52 (76,5%) pacientes con alteración de la RFC (cambios<12lpm en el primer minuto de la recuperación). La RCF no se asoció con la severidad de la EPOC, la gasometría ni los valores de DLCO. En el subgrupo con PECP, el entrenamiento mejoró la RFC en 4 (80%) y la normalizó en 3 (50%). No se observaron complicaciones durante la rehabilitación en ninguno de los pacientes con disfunción autonómica. Conclusiones: La disfunción autonómica es muy prevalente en pacientes con EPOC estable independientemente de la severidad de la enfermedad, y su relevancia ha sido subestimada. La rehabilitación pulmonar es segura en estos pacientes y modifica el grado de esta disfunción autonómica con tendencia beneficiosa. Si la morbilidad y la supervivencia de los pacientes tienen relación con la disfunción autonómica también en nuestro medio merece ser evaluada (AU)

Introduction: Heart rate recovery (HRR) after maximal effort is an indicator of autonomic function and is related to mortality in different diseases. This study was aimed to estimate prevalence of autonomic dysfunction in patients with chronic obstructive pulmonary disease (COPD) and assess potential clinical effects of a pulmonary rehabilitation program (PRP). Patients and methods: Transversal study of 68 stable COPD patients (71±8 years; 65 men and 3 women; FEV1 36.8±11.9%) who received a PRP consisting of 5-week general and specific training (25 sessions). Cycle ergometry test (CET) was performed in all patients prior to the PRP. In a subset of 12 patients, CET was performed both previously and after rehabilitation. The primary end point was the prevalence of autonomic dysfunction as assessed by abnormal heart rate recovery in the first minute of recovery following a maximal symptom limited CET, and the potential changes following a normalised PRP. Results: A total of 52 (76.5%) patients showed abnormal HRR (i.e. change from peak exercise to first recovery minute <12bpm). HRR was not associated with the severity of COPD, arterial blood gases or DLCO values. The PRP induced significant changes in exercise capacity which was related to improvement of HRR in 4 (80%) and was normalised in 3 (50%). No complications or adverse effects were observed during rehabilitation. Conclusions Autonomic dysfunction is a highly prevalent impairment in COPD patients, irrespective the severity of the disease as assessed by conventional pulmonary function test. Relevance of autonomic dysfunction has been understimated in COPD. Pulmonary rehabilitation is safe and modifies the degree of autonomic dysfunction with potential benefits. The relatioship of morbidity and mortality with autonomic dysfunction in COPD in our setting remains to be evaluated (AU)

Entrenamiento de los músculos respiratorios: ¿sí o no? / Respiratory muscle training: yes or no?

Introducción Existen numerosos ensayos clínicos y experimentales que han puesto en evidencia los beneficios del entrenamiento de los músculos respiratorios (EMR) en pacientes con enfermedades crónicas respiratorias o extrapulmonares. Específicamente, estos estudios han demostrado que el entrenamiento de músculos inspiratorios y espiratorios mediante la respiración ante cargas específicas y controladas produce beneficios funcionales clínicamente relevantes, predecibles y mesurables. A pesar de esta relativa plétora de información respecto a la función y a la estructura muscular respiratoria, hay todavía algunos interrogantes pendientes de contestar que parecen justificar la controversia entre defensores y detractores del EMR. Objetivo El objetivo de este trabajo es revisar críticamente la información disponible para ofrecer un instrumento de consenso basado en la evidencia que oriente el EMR hacia decisiones clínicas y farmacoeconómicas relevantes. Conclusión Este artículo se centra en 5 grupos de cuestiones en los campos de la investigación fisiopatológica, básica, clínica, traslacional y farmacoeconómica del EMR en pacientes con enfermedades respiratorias y en atletas de élite(AU)

Introduction It is clear that circumstantial, experimental and clinical trial evidences support respiratory muscle training as a beneficial strategy in patients with chronic respiratory disease. In recent years, a number of studies have demonstrated that, when training loads are controlled, inspiratory and expiratory muscle training result in important functional benefits. Nevertheless, despite this relative plethora of information regarding not only respiratory muscle function but also structure, there are critical and valuable questions that still remain to be answered and appear to stimulate controversies around the rationale for respiratory muscle training. These controversies translate into the fact that respiratory muscle training has both detractors and defenders in the context of rehabilitation. Objective One critical point is how detractors and defenders can reach an evidence-based consensus to orientate respiratory muscle training towards clinically and pharmaco-economically relevant decisions. Conclusion This article focuses in five groups of questions on the fields of physiopathological, basic, clinical, and pharmaco-economic research regarding respiratory muscle training in patients with respiratory diseases and elite sport athletes(AU)

Oxidised proteins and superoxide anion production in the diaphragm of severe COPD patients.

In the diaphragms of chronic obstructive pulmonary disease (COPD) patients, the nature of oxidatively modified proteins and superoxide anion production were explored. Diaphragm specimens were obtained through thoracotomy because of localised lung lesions in COPD patients (16 severe and eight moderate) and 10 control subjects. Lung and respiratory muscle functions were evaluated. Oxidised proteins were identified using immunoblotting and mass spectrometry. Protein and activity levels of the identified proteins were determined using immunoblotting and activity assays. Lucigenin-derived chemiluminescence signals in a luminometer were used to determine superoxide anion levels in muscle compartments (mitochondria, membrane and cytosol) using selective inhibitors. In severe COPD patients compared with controls, respiratory muscle function was impaired; creatine kinase, carbonic anhydrase III, actin and myosin were oxidised; myosin carbonylation levels were increased five-fold; creatine kinase content and activity and myosin protein were reduced; superoxide anion levels were increased in both mitochondria and membrane compartments; and the percentage of superoxide anion inhibition achieved by rotenone was significantly greater. In severe COPD patients, oxidation of diaphragm proteins involved in energy production and contractile performance is likely to partially contribute to the documented respiratory muscle dysfunction. Furthermore, generation of the superoxide anion was increased in the diaphragms of these patients.

Upregulation of pro-inflammatory cytokines in the intercostal muscles of COPD patients.

Muscle dysfunction is a characteristic feature of chronic obstructive pulmonary disease (COPD). Recent studies suggest that cytokines may operate as local regulators of both muscle function and regeneration. The aim of the present study was to characterise the expression of different cytokines in the external intercostal muscle of COPD. Muscle biopsies were obtained from 25 stable COPD patients and eight healthy controls. Local tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta, -6 and -10 expressions (real-time PCR and ELISA), sarcolemmal damage (immunohistochemistry), and the transcript levels of CD18 were assessed. Muscle TNF-alpha and IL-6 transcripts were significantly higher in COPD patients compared with controls, and IL-1beta and sarcolemmal damage showed a strong tendency in the same direction. Similar results were observed at protein level. The CD18 panleukocyte marker was similar in COPD and controls. Respiratory muscle function was impaired in COPD patients and it correlated to both the severity of lung function impairment and TNF-alpha muscle expression. Chronic obstructive pulmonary disease is associated with the upregulation of pro-inflammatory cytokines in the intercostal muscles. This phenomenon might be involved in respiratory muscle dysfunction.