פעילות גופנית במחלות נשימה כרוניות

Transcription

1 פעילות גופנית במחלות נשימה כרוניות ד"ר רונן בר-יוסף מכון ריאות ילדים מרפאת פעילות גופנית ותזונה נכונה בי"ח רות לילדים, רמב"ם פברואר 2014 במסגרת "רפואת ספורט" - שנה א' SPORTS MEDICINE

2 Physical activity Physical activity as a behavior is probably determined by a complex set of factors including: Health beliefs Personality charatcteristics Exercise-associated symptoms Mood Past behaviors Social Cultural factors External factors (such as climate) Activity level has a strong behavioral component as well as a physical component

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5 PHYSICAL ACTIVITY IN COPD Physical inactivity is common in COPD and is associated with poor outcomes, independent of lung function abnormality Individuals with COPD are physically inactive resulting from their adoption of a sedentary lifestyle One study of directly measured physical activity in 50 individuals with COPD compared with 25 healthy elderly individuals patients with COPD spent significantly less time walking and standing and more time sitting and lying Walking time correlated poorly with the degree of airflow limitation Another study of 163 individuals with COPD and 29 with chronic bronchitis but no airflow limitation directly measured physical activity decreases as disease severity increases

6 Other studies - Physical activity in COPD was found to be associated with: Diffusing capacity 6-minute walk distance Peak aerobic capacity Quadriceps and expiratory muscle strength Fibrinogen C-reactive protein Tumor necrosis factor-α levels Health status Dyspnea Fatigue Degree of emphysema Frequency of exacerbations FEV 1

7 Physical inactivity poor outcome, mortality risk COPD patients + long-term oxygen therapy + regular outdoor activity 4-year survival of 35% vs 18% if they reported no regular outdoor activity 2 Danish cohorts, questionnaire-assessed activity predicted 10-year survival in individuals with COPD high activity level 75% survival versus 45% low activity level 2 longitudinal studies of physical activity directly measured by motion detectors worn on the body relationship between physical inactivity and increased mortality risk

8 Study of 170 clinically stable patients with COPD, directly measured physical activity using an activity monitor was the strongest predictor of 4-year survival physical activity was a stronger predictor of survival than: Lung function 6 MWT Ehocardiographic assessment Doppler-assessed peripheral vascular disease Body mass index Fat-free mass index Dyspnea Health status Depression symptoms Multiple systemic biomarkers

9 Study of 173 patients with moderate-severe COPD physical activity measured from a triaxial accelerometer predicted survival over 5 8 years Lower levels of physical activity hospitalization and rehospitalization in individuals with COPD hospitalized for an exacerbation May be associated with a faster decline in lung function

10 Physiology of Exercise Limitation (COPD) May result from: Ventilatory constraints Pulmonary gas exchange Abnormalities Peripheral muscle dysfunction Cardiac dysfunction Anxiety Depression Poor motivation Any combination of the above Direct association has not been established

11 Ventilatory limitation Ventilatory requirements during exercise are high because : Increased work of breathing Increased dead space ventilation Impaired gas exchange Increased ventilatory demand as a consequence of deconditioning and peripheral muscle dysfunction + Limitation to maximal ventilation during exercise resulting from: Expiratory airflow obstruction Dynamic hyperinflation work of breathing, load and mechanical constraints on the respiratory muscles intensified sense of dyspnea

12 Expiratory airflow obstruction

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14 Gas exchange limitation Hypoxia directly increases pulmonary ventilation through augmenting peripheral chemoreceptor output and indirectly through stimulation of lactic acid production Anaerobic metabolism lactic acidemia muscle task failure

15 מה קורה במחלה?

16 Cardiac limitation Increase in right ventricular afterload Contributing factors: Elevated pulmonary vascular resistance resulting from: Combinations of hypoxic vasoconstriction Vascular injury and/or remodeling Increased effective pulmonary vascular resistance due to erythrocytosis Overloaded right ventricle right ventricular hypertrophy and failure Right ventricular hypertrophy may also compromise left ventricular filling by septal shifts

17 Cardiac limitation Other cardiac complications include: Tachyarrythmias Elevated right atrial pressure (due to air trapping) Some of the substantial physiologic benefits from exercise training may be due to an improvement in cardiovascular function

18 Limitation due to lower limb muscle dysfunction Lower limb muscle dysfunction is frequent in individuals with chronic respiratory disease and is an important cause of their exercise limitation Peripheral muscle dysfunction in individuals with chronic respiratory disease may be attributable to single or combined effects of: Inactivity-induced deconditioning Systemic inflammation Oxidative stress Smoking Blood gas disturbances Nutritional impairment Low anabolic hormone levels Aging Corticosteroid use Skeletal muscle dysfunction is frequently reported as fatigue

19 Limitation due to lower limb muscle dysfunction In many individuals this is the main limiting symptom, particularly during cycle-based exercise lactic acid production for a given exercise work rate ventilatory requirement Improving skeletal muscle function is therefore an important goal of exercise training programs

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21 Limitations due to respiratory muscle dysfunction Static and dynamic hyperinflation respiratory muscles at a mechanical disadvantage Functional inspiratory muscle strength Inspiratory muscle endurance Hypercapnia, dyspnea, nocturnal oxygen desaturation, and reduced exercise performance

22 Mechanical disadvantage

23 FITT of endurance training ACSM s Guidelines for Exercise Testing and Prescription on Frequency, Intensity, Time, and Type [FITT]) can be applied in PR Frequency: three to five times per week Intensity: A high level of continuous exercise (>60% maximal work rate) Time: 20 to 60 min/per session maximizes physiologic benefits (i.e., exercise tolerance, muscle function, and bioenergetics) A Borg dyspnea or fatigue score of 4 to 6 (moderate to severe) or Rating of Perceived Exertion of 12 to 14 (somewhat hard) is often considered a target training intensity

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25 ILD/Pulmonary Fibrosis ILD (diffuse parenchymal lung disease) is a heterogeneous group of disorders in which the lung interstitium and/or alveolar spaces are involved with varying degrees of inflammation or fibrosis

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27 ILD/Pulmonary Fibrosis Typical symptoms of ILD include: Disabling exertional dyspnea Nonproductive cough Fatigue Other symptoms as part of a systemic disease

28 ILD/Pulmonary Fibrosis and exercise Patients with ILD have: Reduced exercise tolerance Low physical activity levels Experience depression and impaired QOL Exercise limitation in ILD has a multifactorial basis including: Ventilatory Cardiocirculatory Gas exchange derangements Skeletal muscle dysfunction

29 Ventilatory People with ILD exhibit a rapid, shallow breathing pattern that is present at rest and worsens during exercise More pronounced in those with more severe disease Respiratory mechanics are not thought to be the major contributor to exercise limitation in most patients 2 studies: most participants had a large ventilatory reserve at the end of exercise despite reduced exercise performance Addition of oxygen and external dead space increased both exercise performance and minute ventilation, suggesting that factors other than ventilatory mechanics are the major limitation Chron Respir Dis. 2010;7(2):101-11

30 Impaired gas exchange Destruction of the pulmonary capillary bed or thickening of the alveolar capillary membrane Ventilation perfusion (V/Q) mismatch Oxygen diffusion limitation Low mixed venous partial pressure of oxygen (PO 2 ) Impressive desaturation on both maximal and submaximal exercise tests, especially in patients with idiopathic pulmonary fibrosis (IPF) Chron Respir Dis. 2010;7(2):101-11

31 Circulatory limitation Peak VO 2 correlated better with measures of circulatory impairment than with measures of ventilatory or gas exchange impairment Results from pulmonary capillary destruction and hypoxic pulmonary vasoconstriction leading to pulmonary hypertension (PHT) cardiac dysfunction PHT is common in patients with IPF Strong relationship PHT and both maximal and submaximal exercise performance An abnormal heart rate response to exercise has also been documented in IPF Chron Respir Dis. 2010;7(2):101-11

32 Skeletal muscle dysfunction Important contributor to exercise limitation in ILD In 41 patients with IPF, Quadriceps force was an independent predictor of VO 2 peak, along with vital capacity and ventilatory equivalent for CO 2 at end exercise Sarcoidosis inverse relationship between quadriceps peak power to the mean daily dose of corticosteroids received (myopathy) Respiratory muscle strength may also have an impact on exercise performance Chron Respir Dis. 2010;7(2):101-11

33 ILD/Pulmonary fibrosis - Skeletal muscle dysfunction Study of 12 persons with ILD leg fatigue was the principal cause of cessation of exercise in 17% and led to cessation of exercise together with the symptom of dyspnea in 58% of patients Quadriceps force correlates to: Symptom of leg fatigue during exercise VO 2 max 6MWD Depression

34 Exercise limitation as a marker of prognosis Resting pulmonary function testing does not reliably predict exercise limitation in ILD Measures of exercise limitation provide an integrated assessment of contributors to functional limitation and disease progression in ILD Strong relationships between exercise test performance and mortality Exercise variables are frequently stronger predictors of prognosis than resting lung function Exercise capacity and exercise-induced hypoxaemia (maximal on submaximal exercise tests), have been linked to prognosis Chron Respir Dis. 2010;7(2):101-11

35 Physical activity recommendations ATS/ERS statement on PR (2013) should be performed Freuqency: most days of the week Intensity: >60% peak VO2 Time: 30 min of aerobic exercise Type: Aerobic/endurance Freuqency: 2-3 times a week Intensity: moderate intensity (50% 85% of the RM1), 2-4 sets of 6-12 repetitions Type: Resistance

36 Let s go to rehab

37 כתובת לשאלות ד"ר רונן בר-יוסף מכון ריאות ילדים מרפאת פעילות גופנית ותזונה נכונה בילדים מכון לאורח חיים בריא בילדים בי"ח רות לילדים, רמב"ם טל' : פקס: סלולרי: מייל: r_bar-yoseph@rambam.health.gov.il