Does inspiratory muscle training provide additional benefits during pulmonary rehabilitation in people with interstitial lung disease? A randomized control trial.

Zaki S ，Moiz JA ，Mujaddadi A ，Ali MS ，Talwar D ... -  《-》

Inspiratory muscle training, with or without concomitant pulmonary rehabilitation, for chronic obstructive pulmonary disease (COPD).

Inspiratory muscle training (IMT) aims to improve respiratory muscle strength and endurance. Clinical trials used various training protocols, devices and respiratory measurements to check the effectiveness of this intervention. The current guidelines reported a possible advantage of IMT, particularly in people with respiratory muscle weakness. However, it remains unclear to what extent IMT is clinically beneficial, especially when associated with pulmonary rehabilitation (PR).   OBJECTIVES: To assess the effect of inspiratory muscle training (IMT) on chronic obstructive pulmonary disease (COPD), as a stand-alone intervention and when combined with pulmonary rehabilitation (PR). We searched the Cochrane Airways trials register, CENTRAL, MEDLINE, Embase, PsycINFO, Cumulative Index to Nursing and Allied Health Literature (CINAHL) EBSCO, Physiotherapy Evidence Database (PEDro) ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform on 20 October 2021. We also checked reference lists of all primary studies and review articles. We included randomized controlled trials (RCTs) that compared IMT in combination with PR versus PR alone and IMT versus control/sham. We included different types of IMT irrespective of the mode of delivery. We excluded trials that used resistive devices without controlling the breathing pattern or a training load of less than 30% of maximal inspiratory pressure (PImax), or both. We used standard methods recommended by Cochrane including assessment of risk of bias with RoB 2. Our primary outcomes were dyspnea, functional exercise capacity and health-related quality of life.  MAIN RESULTS: We included 55 RCTs in this review. Both IMT and PR protocols varied significantly across the trials, especially in training duration, loads, devices, number/ frequency of sessions and the PR programs. Only eight trials were at low risk of bias. PR+IMT versus PR We included 22 trials (1446 participants) in this comparison. Based on a minimal clinically important difference (MCID) of -1 unit, we did not find an improvement in dyspnea assessed with the Borg scale at submaximal exercise capacity (mean difference (MD) 0.19, 95% confidence interval (CI) -0.42 to 0.79; 2 RCTs, 202 participants; moderate-certainty evidence).   We also found no improvement in dyspnea assessed with themodified Medical Research Council dyspnea scale (mMRC) according to an MCID between -0.5 and -1 unit (MD -0.12, 95% CI -0.39 to 0.14; 2 RCTs, 204 participants; very low-certainty evidence).  Pooling evidence for the 6-minute walk distance (6MWD) showed an increase of 5.95 meters (95% CI -5.73 to 17.63; 12 RCTs, 1199 participants; very low-certainty evidence) and failed to reach the MCID of 26 meters. In subgroup analysis, we divided the RCTs according to the training duration and mean baseline PImax. The test for subgroup differences was not significant. Trials at low risk of bias (n = 3) demonstrated a larger effect estimate than the overall. The summary effect of the St George's Respiratory Questionnaire (SGRQ) revealed an overall total score below the MCID of 4 units (MD 0.13, 95% CI -0.93 to 1.20; 7 RCTs, 908 participants; low-certainty evidence).  The summary effect of COPD Assessment Test (CAT) did not show an improvement in the HRQoL (MD 0.13, 95% CI -0.80 to 1.06; 2 RCTs, 657 participants; very low-certainty evidence), according to an MCID of -1.6 units.  Pooling the RCTs that reported PImax showed an increase of 11.46 cmH2O (95% CI 7.42 to 15.50; 17 RCTs, 1329 participants; moderate-certainty evidence) but failed to reach the MCID of 17.2 cmH2O.  In subgroup analysis, we did not find a difference between different training durations and between studies judged with and without respiratory muscle weakness.  One abstract reported some adverse effects that were considered "minor and self-limited". IMT versus control/sham Thirty-seven RCTs with 1021 participants contributed to our second comparison. There was a trend towards an improvement when Borg was calculated at submaximal exercise capacity (MD -0.94, 95% CI -1.36 to -0.51; 6 RCTs, 144 participants; very low-certainty evidence). Only one trial was at a low risk of bias. Eight studies (nine arms) used the Baseline Dyspnea Index - Transition Dyspnea Index (BDI-TDI). Based on an MCID of +1 unit, they showed an improvement only with the 'total score' of the TDI (MD 2.98, 95% CI 2.07 to 3.89; 8 RCTs, 238 participants; very low-certainty evidence). We did not find a difference between studies classified as with and without respiratory muscle weakness. Only one trial was at low risk of bias. Four studies reported the mMRC, revealing a possible improvement in dyspnea in the IMT group (MD -0.59, 95% CI -0.76 to -0.43; 4 RCTs, 150 participants; low-certainty evidence). Two trials were at low risk of bias. Compared to control/sham, the MD in the 6MWD following IMT was 35.71 (95% CI 25.68 to 45.74; 16 RCTs, 501 participants; moderate-certainty evidence). Two studies were at low risk of bias. In subgroup analysis, we did not find a difference between different training durations and between studies judged with and without respiratory muscle weakness.  Six studies reported theSGRQ total score, showing a larger effect in the IMT group (MD -3.85, 95% CI -8.18 to 0.48; 6 RCTs, 182 participants; very low-certainty evidence). The lower limit of the 95% CI exceeded the MCID of -4 units. Only one study was at low risk of bias. There was an improvement in life quality with CAT (MD -2.97, 95% CI -3.85 to -2.10; 2 RCTs, 86 participants; moderate-certainty evidence). One trial was at low risk of bias. Thirty-two RCTs reported PImax, showing an improvement without reaching the MCID (MD 14.57 cmH2O, 95% CI 9.85 to 19.29; 32 RCTs, 916 participants; low-certainty evidence). In subgroup analysis, we did not find a difference between different training durations and between studies judged with and without respiratory muscle weakness.   None of the included RCTs reported adverse events. IMT may not improve dyspnea, functional exercise capacity and life quality when associated with PR. However, IMT is likely to improve these outcomes when provided alone. For both interventions, a larger effect in participants with respiratory muscle weakness and with longer training durations is still to be confirmed.

Ammous O ，Feki W ，Lotfi T ，Khamis AM ，Gosselink R ，Rebai A ，Kammoun S ... -  《Cochrane Database of Systematic Reviews》

Effect of inspiratory muscle training on dyspnea-related kinesiophobia in chronic obstructive pulmonary disease: A randomized controlled trial.

The major symptom of chronic obstructive pulmonary disease (COPD) is dyspnea, which causes dyspnea-related kinesiophobia resulting in avoidance of activities associated with dyspnea or compensation by reducing the rate of activity. The aim of this study was to assess dyspnea-related kinesiophobia and determine the effect of inspiratory muscle training (IMT) on dyspnea-related kinesiophobia in COPD. Forty COPD subjects were randomly allocated to either the IMT or sham group. Both groups' maximal inspiratory pressure (MIP) was assessed weekly. All patients were instructed to perform the training exercises for 15 min twice a day, 5 days a week for a total of 8 weeks. In the IMT group, intensity was set at 30% of MIP and adjusted according to weekly MIP value. In the sham group, intensity remained constant at 15% of initial MIP. Pulmonary function test (PFT), respiratory muscle strength, 6-min walk test (6 MWT), Breathlessness Beliefs Questionnaire (BBQ), Modified Medical Research Council scale (MMRC), modified Borg scale, Hospital Anxiety and Depression Scale (HADS), Saint George's Respiratory Questionnaire (SGRQ), and COPD Assessment Test (CAT) were assessed before and after the intervention. BBQ scores ranged from 18 to 51, with mean values in the IMT and sham groups of 39.80 ± 7.62 and 43.00 ± 6.58, respectively. When between-group differences of all outcome scores were compared, there was a statistically significant improvement in the IMT group than in the sham group (p < 0.05). After IMT, statistically significant decreases in BBQ and modified Borg scores were observed in within groups (p ≤ 0.001). These decreases were significantly greater in the IMT group (p ≤ 0.001). MMRC decreased significantly only in the IMT group (p < 0.001). There was a statistically significant increase in PFT values in the IMT group (p = 0.007-0.045), but no difference in the sham group (p = 0.129-0.886). Both groups showed statistically significant improvement in respiratory muscle strength, 6 MWT distance, and CAT score after 8 weeks (p < 0.05). All HADS and SGRQ scores decreased significantly in the IMT group (p < 0.001), whereas only the SGRQ activity score decreased significantly in the sham group (p = 0.017). Our study provides data on the presence and level of dyspnea-related kinesiophobia in COPD patients. All patients had BBQ scores higher than 11, indicating dyspnea-related kinesiophobia. IMT reduced BBQ score and improved respiratory function, and exercise capacity. Our results also support the other known benefits of IMT such as reduced dyspnea and symptom perception, decreased anxiety and depression, and improved quality of life.

Saka S ，Gurses HN ，Bayram M 《-》

Inspiratory muscle training during pulmonary rehabilitation in chronic obstructive pulmonary disease: A randomized trial.

Although recommended by international guidelines, the benefit of inspiratory muscle training (IMT) in addition to rehabilitation remains uncertain. The objective was to demonstrate the effectiveness of IMT on dyspnea using Borg scale and multidimensional dyspnea profile questionnaire at the end of a 6-minute walk test (6MWT) in patients with chronic obstructive pulmonary disease (COPD) with preserved average maximum inspiratory pressure (PImax) of 85 cm H2O (95% of predicted (pred.) value) and admitted for a rehabilitation program in a dedicated center. In a randomized trial, comparing IMT versus no IMT in 32 COPD patients without inspiratory muscle weakness (PImax >60 cm H2O) who were admitted for pulmonary rehabilitation (PR) for 3 weeks, we evaluated the effect of IMT on dyspnea, using both Borg scale and multidimensional dyspnea profile (MDP) at the end of the 6MWT, and on functional parameters included inspiratory muscle function (PImax) and 6MWT. All testings were performed at the start and the end of PR. In unadjusted analysis, IMT was not found to be associated with an improvement of either dyspnea or PImax. After adjustment on confounders (initial Borg score) and variables of interaction (forced expiratory volume in 1 second (FEV1)), we found a trend toward an improvement of "dyspnea sensory intensity", items from MDP and a significant improvement on the variation in the 2 items of MDP ("tight or constricted" and "breathing a lot"). In the subgroup of patients with FEV1 < 50% pred., 5 items of MDP were significantly improved, whereas no benefit was observed in patients with FEV1 > 50% pred. IMT did not significantly improve dyspnea or functional parameter in COPD patients with PImax > 60 cm H2O. However, in the subgroup of patients with FEV1 < 50% pred., MDP was significantly improved.

Beaumont M ，Mialon P ，Le Ber-Moy C ，Lochon C ，Péran L ，Pichon R ，Gut-Gobert C ，Leroyer C ，Morelot-Panzini C ，Couturaud F ... -  《-》

Effectiveness of 12-week inspiratory muscle training with manual therapy in patients with COPD: A randomized controlled study.

The benefits of inspiratory muscle training (IMT) in patients with COPD were reported. However, its effects are limited in severe COPD patients. Further researches are required in new and complementary modalities demonstrating IMT efficacy in severe COPD patients. This study aims to investigate effects of manual therapy (MT) additional over IMT on functional capacity, respiratory muscle strength, pulmonary function, dyspnea, fatigue, and quality of life in severe COPD patients. Sixty patients with COPD in GOLD stage III-IV were included in this prospective single-blind randomized trial. Patients were randomly assigned to receive either MT additional over IMT at 40% of maximal inspiratory pressure (MIP) (n = 30) or only IMT (n = 30) for 12 weeks. MT group received MT during 12 weeks for 30 min additional to IMT. Pulmonary function, respiratory muscle strength, functional capacity, dyspnea, fatigue, and quality of life were evaluated by spirometry, mouth pressure device, six-minute walk test, Modified Medical Research Council (mMRC) dyspnea scale, fatigue severity scale, and St. George's Respiratory Questionnaire (SGRQ), respectively. MT group had significantly greater improvement in FEV1%, FVC%, PEF%, respiratory muscle strength, function, dyspnea, fatigue, and quality of life compared with IMT group (p < 0.05). 6MWT (p < 0.001, effect size Cohen's d: 0.915), MIP (p < 0.001, effect size Cohen's d: 1.235), and mMRC score (p < 0.001, effect size Cohen's d: 0.982) were significantly improved in IMT with MT group. This study demonstrated that subjects in IMT with MT group had improved outcomes in functional capacity, respiratory muscle strength, pulmonary function, dyspnea, fatigue perception, and quality of life compared with alone IMT group.

Buran Cirak Y ，Yilmaz Yelvar GD ，Durustkan Elbasi N 《-》