Oxygen therapy during exercise training in chronic obstructive pulmonary disease

 

Abstract

Background

Exercise training within the context of pulmonary rehabilitation improves outcomes of exercise capacity, dyspnea and health-related quality of life in individuals with chronic obstructive pulmonary disease (COPD). Supplemental oxygen in comparison to placebo increases exercise capacity in patients performing single-assessment exercise tests. The addition of supplemental oxygen during exercise training may enable individuals with COPD to tolerate higher levels of activity with less exertional symptoms, ultimately improving quality of life.

Objectives

To determine how supplemental oxygen in comparison to control (compressed air or room air) during the exercise-training component of a pulmonary rehabilitation program affects exercise capacity, dyspnea and health-related quality of life in individuals with COPD.

Search methods

All records in the Cochrane Airways Group Specialized Register of trials coded as 'COPD' were searched using the following terms: (oxygen* or O2*) AND (exercis* or train* or rehabilitat* or fitness* or physical* or activ* or endur* or exert* or walk* or cycle*). Searching the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), MEDLINE, EMBASE and CINAHL databases identified studies. The last search was carried out in June 2009.

Selection criteria

Only randomized controlled trials (RCTs) comparing oxygen-supplemented exercise training to non-supplemented exercise training (control group) were considered for inclusion. Participants were 18 years or older, diagnosed with COPD and did not meet criteria for long-term oxygen therapy. No studies with mixed populations (pulmonary fibrosis, cystic fibrosis, etc) were included. Exercise training was greater than or equal to three weeks in duration and included a minimum of two sessions a week.

Data collection and analysis

Two review authors independently selected trials for inclusion in the review and extracted data. Weighted mean differences (WMD) with 95% confidence intervals (CI) were calculated using a random-effects model. Missing data were requested from authors of primary studies.

Main results

Five RCTs met the inclusion criteria. The maximum number of studies compared in the meta-analysis was three (31 on oxygen versus 32 control participants), because all included studies did not measure the same outcomes. When two studies were pooled, statistically significant improvements of oxygen-supplemented exercise training were found in constant power exercise time, WMD 2.68 minutes (95% CI 0.07 to 5.28 minutes). Supplemental oxygen increased the average exercise time from 6 to 14 minutes; the control intervention increased average exercise time from 6 to 12 minutes. Constant power exercise end-of-test Borg score (on a scale from 1 to 10) also showed statistically significant improvements with oxygen-supplemented exercise training, WMD -1.22 units (95% CI -2.39 to -0.06). One study showed a significant improvement in the change of Borg score after the shuttle walk test, by -1.46 units (95% CI -2.72 to -0.19). There were no significant differences in maximal exercise outcomes, functional exercise outcomes (six-minute walk test), shuttle walk distance, health-related quality of life or oxygenation status. According to the GRADE system most outcomes were rated as low quality because they were limited by study quality.

Authors' conclusions

This review provides little support for oxygen supplementation during exercise training for individuals with COPD, but the evidence is very limited. Studies with larger number of participants and strong design are required to permit strong conclusions, especially for functional outcomes such as symptom alleviation, health-related quality of life and ambulation.

 

Plain language summary

Oxygen therapy during exercise training in chronic obstructive pulmonary disease (COPD)

People with COPD often have severe shortness of breath that prevents them from performing their everyday activities. Formal rehabilitation programs that include exercise training improve stamina, decrease breathlessness and enhance quality of life. Use of oxygen during exercise may provide additional benefit. We conducted a review to determine the effectiveness of adding oxygen to exercise training in comparison to exercise training without oxygen supplementation in people with COPD. Five studies addressed the question although, because of measurement of different outcomes, the maximum number available for looking at any individual outcome was three (31 patients receiving oxygen versus 32 not). People with COPD may exercise longer and have less shortness of breath when using oxygen during an exercise-training program. These studies did not look at the effect of oxygen on shortness of breath in daily life. From the evidence to date, it is not possible to determine whether individuals with COPD should use oxygen during exercise training. Stronger studies with more participants are required in order to understand how oxygen-supplemented exercise training for people with COPD will affect their shortness of breath, activity and quality of life.

 

摘要

背景

COPD病患運動訓練過程中使用氧氣療法

肺部復健中執行運動訓練可幫助COPD病患改善其運動能力、呼吸困難與健康有關生活品質等成果。病患進行單一評估之運動測試中，補充氧氣比使用安慰劑更能增加病患的運動能力。在運動訓練過程中額外補充的氧氣可能可以讓COPD病患減少費力耗竭的症狀而承受更大的活動量，甚至改善其生活品質。

目標

本研究比較COPD患者進行肺部復健的運動訓練過程中補充氧氣與對照組(提供壓縮空氣或室內空氣)是否會影響其運動能力、呼吸困難和健康相關生活品質。

搜尋策略

以下列關鍵字檢索所有在Cochrane Airways Group Specialized Register資料庫中有「COPD」編碼的試驗：(oxygen* or O2*) AND (exercis* or train* or rehabilitat* or fitness* or physical* or activ* or endur* or exert*or walk* or cycle*)，同時也檢索Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), MEDLINE, EMBASE and CINAHL資料庫，檢索至2007年6月

選擇標準

僅納入比較提供氧氣的運動訓練與未提供氧氣的運動訓練(對照組)的隨機性對照試驗。所有受試者都年滿18歲，被診斷患有COPD且不符合需接受長期氧氣療法之條件。排除混合診斷別者(如肺部纖維化或囊腫纖維化等)的試驗。運動訓練至少須維持3星期以上且一星期至少進行兩次的訓練課程。

資料收集與分析

兩個審閱者獨立篩選納入此文獻回顧的是燕並萃取資料。以隨機效應模式計算加權平均差(WMD)及95％信賴區間。此外，向原始作者索取遺漏的數據資料。

主要結論

5個臨床隨機試驗符合納入標準。因為所有納入的試驗並未測量相同的成果，統合分析中比較的研究值為3(31位接受氧氣受試者與32位對照受試者)。將兩個試驗放在一起時，接受氧氣的受試者在運動訓練過程中進行固定肌力運動訓練時間達統計上的顯著改善，WMD值為2.68分鐘(95％信賴區間介於0.07至5.28分鐘間)。提供氧氣可將平均運動時間由6分鐘增加至14分鐘，對照的介入治療可將平均運動時間由6分鐘提升至12分鐘。補充氧氣的運動訓練組之持續肌力訓練結束休息時的費力量表(Borg量表, 1至10分)的得分也顯?改善，WMD值為−1.22單位(95％信賴區間介於−2.39至−0.06間)。有一個試驗顯示在來回走路試驗(Shuttlewalking test)後，費力量表的得分明顯改善−1.46單位(95％信賴區間介於−2.72至−0.19間)。但在最大運動成果、功能性運動成果(6分鐘走路試驗)、來回走路試驗、健康相關生活品質或氧合狀態等並沒有明顯的差異。因為研究品質的限制，GRADE系統分析得多數成果都是低品質的。

作者結論

本文獻回顧對COPD病患進行運動訓練中補充氧氣的效果提供一些支持證據，但這些證據的效力有限。建議以更多樣本與更嚴謹的研究設計以獲得更有力的結論，如症狀緩解、健康相關生活品質和步行的功能性成果。

翻譯人

此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。

總結

對於COPD患者在運動訓練過程中進行氧氣治療。COPD患者通常會出現嚴重的呼吸短促症狀並影響其每天日常活動的表現，正規的復健過程包括了藉由進行運動訓練來提升耐力、減少無法喘氣的機率並且強化生活品質，在運動過程使用氧氣可能可以提供一些附加的效益，我們的藉由審閱的過程來決定在COPD患者進行運動訓練過程中添加氧氣的效益，並將其結果與在運動訓練過程中沒有提供氧氣的結果加以比較，有5個試驗研究滿足了這個疑問，雖然這些研究的試驗成果並不相同，察看任何個別試驗成果的最大可用數值為3(31名受試者接受補充氧氣，32名患者沒有接受補充氧氣)，在運動訓練課程中使用氧氣可以使COPD患者接受更長時間的訓練並可以減少發生呼吸短促的機率，這個研究並沒有針對補充氧氣對於每天生活中發生呼吸短促的影響進行討論，由目前可得的證據並無法確定是否COPD患者應該在進行運動訓練的過程中使用氧氣，因此需要藉由針對較大數量受試者進行研究以取得較有力的研究結果，以瞭解補充氧氣對於進行運動訓練的COPD患者是否會對其呼吸短促現象、活動力和生活品質產生影響。