PULMONARY REHABILITATION IN COPD PATIENTS. OBSERVATIONAL STUDY

Med. Surg. J. Rev. Med. Chir. Soc. Med. Nat., Iaşi 2018 vol. 122, no. 3 INTERNAL MEDICINE - PEDIATRICS ORIGINAL PAPERS PULMONARY REHABILITATION IN COPD PATIENTS. OBSERVATIONAL STUDY Mara Bălteanu 1, C. Kamal 2, Diana Kamal 3, Paraschiva Postolache 4,5*, Rodica Trăistaru 2 1. Marius Nasta National Institute of Pneumophtysiology, Bucharest University of Medicine and Pharmacy Craiova 2. Faculty of Medicine 3. Elga Polyclinic, Craiova Grigore T. Popa University of Medicine and Pharmacy Iasi Faculty of Medicine 4. Department of Medical Specialties (I) 5. Rehabilitation Clinical Hospital, Iasi * Corresponding author. E-mail: par.postolache@umfiasi.ro PULMONARY REHABILITATION IN COPD PATIENTS-OBSERVATIONAL STUDY (Abstract): The aim was to analyze the effects of an 8-week pulmonary rehabilitation (PR) program on quality of life (QoL), physical performance (6MWD value - six-minute walk test) and pulmonary function in patients with mild and moderate COPD. Material and methods: 23 subjects with COPD with FEV1 50% were assigned to a clinic treatment group (n=12) or a home exercise group (n=11). Subjects in the first group received supervised exercise program over a 6-week period after 2 weeks inpatient PR program. Subjects in the second group received the same exercise program initially in hospital, followed by 6 weeks of home exercises, reinforced by a clinic visit at 2 weeks. Measured outcomes were the 6MWD, the generic QoL scale St. George s Respiratory Questionnaire Disease (SCRQ) and statist i- cal analysis by ANOVA test. Results: Both groups showed clinically and statistically significant improvements in 6MWD and SCRQ scores at 8 weeks; improvements were still evident in both groups at 3 months. By 8 weeks, SGRQ scores had improved in both groups with 28% and 24%; 6 MWD had improved with 13% and 5%, and important differences were observed in the mean changes of 6MWD: 56.42 m in the first group, 17.7 m in the second group. At 3 months, the results of both groups were substantially and about equally i m- proved over baseline measurements. Conclusions: Subjects in the first group were more satisfied with the overall outcome of their rehabilitation treatment compared with subjects in the second group. Keywords: PULMONARY REHABILITATION, COPD, QUALITY OF LIFE, PHYSICAL PERFORMANCE, PULMONARY FUNCTION. Chronic Obstructive Pulmonary Disease (COPD) is a common preventable and treatable disease, characterized by persistent airflow limitation that is usually progressive and associated with an enhanced chronic inflammatory response in the airways and the lung to noxious particles or gases (1). COPD patients must face limitations in daily activities and reduced quality of life (QoL) caused by dyspnea, airflow limitation, skeletal muscle dysfunction and comorbidities (1, 2, 3, 4, 5). The major 474

Pulmonary rehabilitation in COPD patients. Observational study goals of stable COPD management are to reduce symptoms, increase participation in daily living activities and improve healthrelated quality of life (HRQoL) (1, 2, 3, 6). The pharmacological treatment of COPD is main target is to reduce the degree of airflow limitation and there is evidence that FEV1 has a relatively poor correlation with symptoms, HRQoL and daily functioning (7, 8, 9). American Thoracic Society (ATS) and European Respiratory Society (ERS) recommendations for the management of COPD are to use of pulmonary rehabilitation programs (PRPs) for all groups of risk of the illness (A, B, C, D), especially selfmanagement techniques to improve exercise tolerance and HRQoL, and to reduce symptoms like dyspnea and fatigue (1, 2, 10, 11). PRPs have been shown not only to improve exercise capacity and health status and to reduce dyspnea and but also to diminish the use of healthcare resources (2, 6, 12-18). We carried out a comparative study single blind to analyze the effects of an 8 weeks rehabilitation program on dyspnea, HRQoL, physical performance and pulmonary function in patients with mild and moderate COPD (19, 20). The aim of the study was to evaluate functional capacity and health status at 8 weeks of physical treatment and at 3 months after conclusion of PRP in patients regularly followed in respiratory health services. MATERIAL AND METHODS All patients with a confirmed diagnosis of COPD with FEV1>50% admitted to a PRP at Physical Medicine and Rehabilitation Department, Hospital No. 2, Craiova, between January 2018 and May 2018 were recruited (tab. I). The diagnosis of COPD was made according to GOLD definition and classification (1, 7, 9). All patients received pharmaceutical treatment according with COPD GOLD stage. The respiratory specialist oversaw confirming the diagnoses, treatment and verifying exclusion criteria. PRP of mild/moderate COPD patients included: the patient selection and initial evaluation, the goal developing, the ensuring the smooth running of the program, the evaluation of patient outcomes, the performing of long/term follow-up. On admission, patients were excluded from this study if they had a diagnosis of other pulmonary disease, with unstable cardiac conditions, neuromotor limitation or COPD patients with a recent exacerbation (in the preceding 4 weeks). TABLE I The main characteristics of the study patients Study group 1 (G1) Study group 2 (G2) No of patients 12 11 Gender 10 M / 2 W 8 M / 3 W Mean age 46 (±8) years old 48 (±7) years old Own place 7 V, 5 T 6 V, 5 T Smokers 13 10 Tobacco index 23 PA 26 PA (mean) Onset of COPD 3.2 years 4.4 years (mean) FEV 1 initial 65.5 % 67.82 % W = women, M = men, V = village, T = town Study design The study design as a flow diagram: pre-to-post comparisons were made in those patients (fig. 1). 475

Mara Bălteanu et al. Fig. 1. A flow diagram of study design The patients with mild and moderate COPD were begun 8 weeks of PRP in the hospital. Sessions were supervised by a rehabilitation therapist. According with patient s preference and to the probability that patient maintain the exercise at home, patient was randomized in two study groups. Both groups started PRP in hospital for 2 weeks. After, the study group (G1) - received supervised exercise in hospital (outpatient PRP). The second group of patients (G2) received the same exercise program initially - in hospital, followed by 6 weeks of PRP at home residence, reinforced by a clinic visit at 2 weeks. We performed a complete history, physical examination, chest radiography, laboratory and pulmonary function data. The studied parameters were: dyspnea - using Medical Research Council (MRC) scale (16); pulmonary lung function: FEV1 and FEV1/FVC % using a spirometer (Vitalograph) connected to a computer, for a data analysis (1,8,9); exercise capacity: six-minute walking distance (6 MWD) according to the ATS Guidelines (17); 476

Pulmonary rehabilitation in COPD patients. Observational study QoL using St. George s Respiratory Questionnaire Disease (SGRQ) - a standardized, self-administered questionnaire for measuring impaired health and perceived HRQL in airways disease (21, 22). All evaluations were performed by the pulmonary physician, without knowing the location of the PRP. Patients were able to perform the inpatient (2 weeks) and outpatient (6 weeks) RPPs. The size of group at any session was limited to 5 patients. The rehabilitation methods we used were: monitoring pharmacotherapy, education 15 minutes daily sessions (breathing retraining, energy conservation, nutritional and medication education, smoking cessation, teaching the patients how to cope with feelings of dyspnea), physical training and educational and psychological management. The second part was devoted to physical training, preceded by Jacobson s technique, for twice-daily, 3 days a week, for eight weeks, 30-minute sessions, at 75-80% of the load achieved on the incremental pre-exercise test carried out at enrollment, and consisted of: respiratory muscle training - inspiring against a closed glottis, pursed lips breathing, expiratory abdominal augmentation and synchronization of thoracic and abdominal movements; modified proprioceptive neuromuscular training (four periods with 5 minutes of repetitive large muscle dynamic exercise separated by 1 minute with mild exercise), including stretching as part of the warm-up period and of the cool-down, respectively; complete lower extremity aerobic training on a cycle ergometer (Aerobic 2100) / the morning session; training workload was assessed daily in the inpatients and weekly in the outpatients. After 2 weeks of inpatients PRP, the patient of G1 continued physical therapy in hospital 3 days a week like outpatient PRP. The patient of G2 continued PRP at home. The study was approved by the Ethics Committee of the University of Medicine and Pharmacy Craiova and was carried out in concordance with the World Medical Association Declaration of Helsinki (2000). We have obtained informed consent from our patients for the treatment and for their medical data to be used in a study. Statistical analysis Data are presented as mean ± standard deviation for continuous variable and percentages for categorical variables. The difference between means was determined using Student s t-test. Differences parameter values between groups were tested by ANOVA test. A p-value <0.05 was considered statistically significant. The statistical analysis was performed using SPSS 8.0 for Windows; SPSS Inc., Chicago, IL, SUA and applied according to the current methodology. RESULTS After 8 weeks of PR all subjects reduce dyspnea - we obtained a fall in breathlessness mean score, had a significant, albeit small, improvement in mean FEV1, extended exercise endurance (6 MWD increased significantly), enhanced HRQoL (we considered 4 points as minimal clinically important difference as stated by Paul Jones), reduced use of pharmacological agents (tab. II). For G1 we did not identify any significant difference between the mean values for FEV1 measured at three points (p ANOVA = 0.759> 0.050). Spirometry showed at all patients, especially in younger, small increases in FEV1 after 8-week 477

Mara Bălteanu et al. inpatient PR. At 3-month FEV1 increased at 67.83 %. For G2 we did not identify any significant difference between the mean FEV1values at three points (p ANO- VA=0,913>0,050); spirometry showed small increases in FEV1 after 8-week PR (FEV1=69.05%) compared to initial (FEV1=68.8%). For FEV1 we have ident i- fied no statistically significant difference between G1 and G2 (tab. II). Parameter Study group TABLE II Results of PRP in the two-study group Baseline After 8-week rehabilitation After 3 months Mean Std.dev. CI.95% p Mean Std.dev. CI.95% p Mean Std.dev. CI.95% p FEV1 % predicted G1=12 65.50 7.62 G2=11 67.82 7.32 60.66-70.34 62.90-72.73 0.466 66.58 7.90 69.09 7.58 61.56-71.60 64.00-74.18 0.447 67.83 7.47 68.73 6.68 63.09-72.58 64.24-73.21 0.766 MRC scale score G1=12 1.67 0.89 1.10-2.23 0.92 0.79 0.41-1.42 0.92 0.79 0.41-1.42 0.10 0.103 0.360 G2=11 0.73 0.68 0.27-1.19 0.45 0.44 0.16-0.75 0.64 0.62 0.22-0.75 Well-being (SGRQ total score) G1=12 31.50 6.50 G2=11 28.36 9.91 27.37-35.63 21.70-35.02 0.376 22.58 7.28 20.91 9.39 17.96-27.21 14.60-27.21 0.636 24.00 6.94 26.36 7.07 19.59-28.41 21.61-31.12 0.428 6 MWD (m) G1=12 434.08 30.83 G2=11 407.82 70.44 414.50-453.67 360.50-455.14 490.50 43.26 0.253 425.55 68.82 463.01-517.99 379.31-471.78 500.25 45.91 0.012 416.09 71.16 471.08-529.42 368.29-463.90 0.003 For G1, we obtained a fall in breathlessness mean score (MCR scale) with 45% of the initial score after 8 weeks; we identified a significant difference at the boundary between the MRC mean values to three times (p ANOVA = 0.049 <0.050). In the G2, MCR mean score decreased with 38% after 8 weeks, but at 3 months was decreased only with 12%, without significant difference between the mean values (p ANOVA = 0.553> 0.050). We have identified a statistically significant difference only for the initial investigation (p = 0.010 Student <0.050), between G1 and G2. For G1, we identified a significant difference between the mean values measured for SGRQ at three points (p ANOVA = 0.007<0.050). At the end of PRP there was an improvement in health status in both groups. At 8 weeks in G1, mean SGRQ score increased with 28% and with 24% in 3 months after PRP compared by baseline (tab. II). On the contrary, in G2, if at 8 weeks SGRQ score was better that before PRP with 26%, there were changes in total SGRQ score, with a tendency to get worst at 3 months after PRP, when the mean SGRQ score was increased only with 7% 478

Pulmonary rehabilitation in COPD patients. Observational study compared by baseline (tab. II). Comparing the results between G1 and G2 we have not identified at any of the three points, any statistically significant difference. After PRP, in the G1, mean 6MWD was clinically and statistically significant increased at 8 weeks (+13%) (tab. II). We identified a significant difference between the mean 6MWD values at three points for G1 (p ANOVA = 0.001<0.050). In G2, mean 6MWD was increased at 8 weeks (+17.7m =5%) compared with initial values. After completing PRP inpatient, 6MWD was increased only with 2% compared with baseline (tab. II). For G2 did not identify any significant difference at three points (p ANOVA = 0.840> 0.050). Comparing the results between the two groups we have not identified at baseline, a statistically significant difference, but the investigation of the second and the final difference between the two groups became statistically significant difference (the end p Student = 0.003, the intermediate p Student = 0.012). Although all parameters studied had a favorable evolution, when we performed linear regression equation for the mean initial values and intermediary, respectively final values of the studied parameters, we found that initial value are predictive for both intermediary and final values only in G1 (fig. 2, 3, 4). Fig. 2. The frequency graphs of linear regression equations for MRC Fig. 3. The frequency graphs of linear regression equations for SGRQ 479

Mara Bălteanu et al. Fig. 4. The frequency graphs of linear regression equations for 6MWD DISCUSSION The benefits of the PRP in the management of patients with chronic respiratory disease already known and well-established (1, 2, 3, 6-12, 14, 15), were also observed in this study. The studies published so far in the literature show the positive effects rehabilitation has in patients with moderate to severe (23, 24), very severe COPD (25) or comorbidities (26). The present study highlights the benefits of PR in patients diagnosed with COPD with FEV1> 50% without comorbidities, rehabilitation initially performed under hospital conditions, then at home. In both groups, after PRP, patients showed improvement in health status and but not in functional capacity. Studied patients have carried out a PRP during two weeks in hospital treatment, followed by six weeks at home (G2) or hospital (G1). 2017 GOLD appreciates the minimum duration of an effective PRP is at least 6 weeks, the effectiveness increases with increasing duration (1). Our program duration was greater than the minimum recommended two weeks of GOLD 2014 and the British Thoracic Society (6 weeks) (27). Compared with other studies (24, 25), the duration of the program is average, and there are programs for 4 weeks or three years (23), in moderate-severe COPD (24), and 26 weeks for patients with severe ventilatory dysfunction (25). Other studies evidenced that longer programs seem to enhance long-term effects (23, 28). Initiation of the program was carried out under hospital conditions, which is considered necessary given the fact that patients have never carried out such a program and requiring the careful monitoring of respiratory function during exercise. Subsequent completion (out-patient and home-training) was done to capture the effects of PR in the two situations. We mention that carrying home-training program was accepted in patients who did not have easy access to the out-patient services. In the literature we didn t find any studies we could refer to, the more often patients performing an outpatient PRP (24, 25, 29). The limited number of patients compared to other studies (25, 30, 31), is explained by the inclusion only patients with FEV1>50%, without comorbidities and poor adherence for this form of nonpharmacological treatment. We do not have an explanation for the poor adherence of G2 to the PRP, as both groups were similar in terms of baseline clinical and demo- 480

Pulmonary rehabilitation in COPD patients. Observational study graphic characteristics and similar PRP benefits in both groups (tab. I). Translation of the acquired skills to patient s lifestyle may be prevented by different barriers: lack of self-confident, cognitive impairment and behavioral issues, lack of motivation and the presence of physical barriers at home or in the community (25, 32). The G2 poor adherence to follow-up testing could be explained by the fact they were also less compliant to exercise. A possible explanation for the worst longterm results with patients that did cycling during PRP, could be the difficult maintaining this exercise regularly at home and consequently they became less active. We mention that most patients with COPD have a respiratory function with a severe or very severe reduction (FEV1 < 50%), highlighting the absence or ineffectiveness of programs for early detection of smoking-induced pathology or respiratory hazards. Most patients included in the study came from rural areas. Unlike other studies in which correlations are made between respiratory function parameters (29, 30, 31), in our study we followed the recovery program effects on pulmonary function, exercise capacity (6MWD), dyspnea (MRC) and quality of life (SGRQ) after 6 weeks of rehabilitation and three months after the end of the program. In our study we didn t set out to achieve a target intensity of 80% of peak work rate but strived that in the first 2 weeks of the rehabilitation program, patients would learn a correct respiratory pattern (4 stage), with physical effort during exhale. For FEV1 parameter we cannot appreciate an improvement percentage, given the irreversible character of the lesions and respiratory function degradation in COPD, regardless of the therapeutic method applied. 6MWD values were in the concordance with the literature (29, 31). The improvement of 6MWD after the rehabilitation was higher compared with other published results (29,31). This is because our patients perform daily physical exercises; most of them come from rural areas. Also, our patients were complaining to proprioceptive training. Like other literature data (33) our results confirmed that regular aerobic exercise is associated with minimal increase in overall health status and walking selfefficacy, expressed through 6 MWD, as well as a reducing progression of dyspnea, especially during activities of daily living effort. After 12 weeks the results of PR program are decreasing, similar another publication (34), perhaps due to limiting interest for constant and daily proprioception training. As limitations of this study we can consider the small number of patients, the short duration of follow-up phase, compared with other studies (35, 36) and lack of comorbidities. Poor adherence has a detrimental effect on morbidity, mortality and health care resources (37). In appropriate future, PRP in Romania should become a current medical option in all disabled patients, so the mentioned limits will be eliminated. CONCLUSIONS The results of the present study show that the proprioception is fundamental for sensory/motor control over thorax joint stability, so our proprioceptive neuromuscular training offers optimal control of respiratory movements and is essential in patients with COPD. Combining in-patient / out-patient or in- 481

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