PULMONARY REHABILITATION has become an established

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1 1788 ORIGINAL ARTICLE Psychosocial Conditions Do Not Affect Short-Term Outcome of Multidisciplinary Rehabilitation in Chronic Obstructive Pulmonary Disease Jacob C. Trappenburg, MSc, PT, Thierry Troosters, PhD, PT, Martijn A. Spruit, PhD, PT, Nele Vandebrouck, MSc, PT, Marc Decramer, MD, PhD, Rik Gosselink, PhD, PT ABSTRACT. Trappenburg JC, Troosters T, Spruit MA, Vandebrouck N, Decramer M, Gosselink R. Psychosocial conditions do not affect short-term outcome of multidisciplinary rehabilitation in chronic obstructive pulmonary disease. Arch Phys Med Rehabil 2005;86: Objectives: To characterize patients referred for pulmonary rehabilitation on a large number of psychologic and sociodemographic variables and to determine the contribution of these variables on the response to rehabilitation. Design: Cross-sectional, explorative. Setting: University hospital and outpatient clinic. Participants: Eighty-one consecutive patients with chronic obstructive pulmonary disease (forced expiratory volume in 1 second, 40% 16% of predicted) were included in outpatient pulmonary rehabilitation. Intervention: Multidisciplinary rehabilitation program. Main Outcome Measures: Pulmonary function, exercise capacity (Wmax, 6-minute walk test [6MWT]), Chronic Respiratory Disease Questionnaire (CRDQ), Modified Pulmonary Functional Status and Dyspnea Questionnaire (PFSDQ-M), anxiety and depression (Hospital Anxiety and Depression Scale [HADS]) were assessed before and after 3 months rehabilitation. In addition, psychosocial adjustment, social support, marital status, mode of transportation, education, employment, and smoking status were assessed at the start of the rehabilitation. Results: Rehabilitation improved exercise performance (Wmax, 6 12W; P.01; 6MWT, 41 72m; P.001), quality of life (CRDQ score, points; P.001), functional status (PFSDQ-M activity score, 8 11 points; PFSDQ-M dyspnea score, 6 12 points; PFSDQ-M fatigue score, 4 8 points; all P.01), HADS anxiety score ( 2 3 points, P.01), and HADS depression score ( 3 3 points, P.001). In single regression analysis, only baseline depression was weakly negatively correlated with the change in maximal workload. No other relations of initial psychologic or sociodemographic variables with outcome were observed. Conclusions: The effects of rehabilitation are not affected by baseline psychosocial factors. Patients with less favorable psychologic or sociodemographic conditions can also benefit from pulmonary rehabilitation. The multidisciplinary approach From the Respiratory Rehabilitation and Respiratory Division, University Hospitals, Katholieke Universiteit, Leuven; and Faculty of Kinesiology and Rehabilitation Sciences, Katholieke Universiteit, Leuven, Belgium. Supported by FWO-Vlaanderen (grant nos , G ) and Katholieke Universiteit (grant no. PDM 04/230). No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors or upon any organization with which the authors are associated. Reprint requests to Rik Gosselink, PhD, PT, Div Respiratory Rehabilitation, University Hospital Gasthuisberg, Herestraat 49, 3000 Leuven, Belgium, rik.gosselink@uz.kuleuven.ac.be /05/ $30.00/0 doi: /j.apmr of the rehabilitation program might have contributed to this improvement. Key Words: Pulmonary disease, chronic obstructive; Rehabilitation by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation PULMONARY REHABILITATION has become an established part of the management of chronic obstructive pulmonary disease (COPD) and partially restores function and quality of life (QOL) of these patients. A meta-analysis 1 and recent studies 2-5 have demonstrated improvements in exercise capacity, health-related quality of life (HRQOL), daily functioning, cognitive and psychologic functioning, and a decrease in utilization of health care resources. Although effects of pulmonary rehabilitation have been recognized in patient groups, responses of individual patients to this intervention are highly variable. Knowledge about baseline variables that can affect the outcome of pulmonary rehabilitation might be important to refine selection criteria or to adjust interventions to individual patients needs. Until recently, only general selection criteria have been used to refer patients for pulmonary rehabilitation. ZuWallack 6 proposed the most commonly used criteria for patient selection, that is, reduced functional status, absence of comorbidity, and significant level of motivation. However, these are mainly based on empirical observations. Two studies 7,8 reported that less severe ventilatory limitation during incremental exercise was associated with a greater improvement in walking distance. A lower baseline exercise capacity and muscle weakness 8 explained only 32% of the variance in exercise improvement in a multiple discriminant analysis. 8 Age, 9 smoking status, 10 and degree of pulmonary function impairment 11,12 did not affect outcome of pulmonary rehabilitation programs. We hypothesized that psychologic and sociodemographic conditions could also interfere with rehabilitation outcome. Psychologic and social problems are more prevalent in COPD 13,14 and have been shown to influence adherence to pulmonary rehabilitation. Therefore, consideration of these factors may be helpful in appropriate patient selection. 15 In the present study, we aimed to characterize a group of patients referred for pulmonary rehabilitation on a large number of psychologic and sociodemographic variables. In addition, we investigated whether baseline psychologic and sociodemographic variables could be identified as determinants of changes in exercise performance and HRQOL after pulmonary rehabilitation. METHODS Subjects and Design We investigated 81 consecutive patients with COPD visiting the outpatient clinic for enrollment in a pulmonary rehabilita-

2 PSYCHOSOCIAL CONDITIONS AND OUTCOME OF PULMONARY REHABILITATION, Trappenburg 1789 tion program, prospectively. Patients who met the following 4 criteria were eligible for inclusion: (1) forced expiratory volume in 1 second (FEV 1 ) and forced vital capacity (FVC) below 70%; (2) clinical condition stable at inclusion with no recent exacerbation; (3) symptoms of dyspnea and reduced exercise capacity present despite optimal medical care; and (4) willing to participate in the program. We assessed patients using physiologic tests, QOL questionnaires, and specific psychosocial questionnaires. In addition, we collected sociodemographic variables. Outcome of pulmonary rehabilitation was assessed after 3 months. The study was approved by the ethics commission of the hospital and all patients gave informed consent to participate in the study. Pulmonary Function All patients underwent spirometry and whole body plethysmography (Vmax Autobox). a All tests were performed according to the European Respiratory Society guidelines for pulmonary testing and results were expressed as a percentage of predicted value using the normative values of Quanjer et al. 16 Transfer factor for carbon monoxide (TLCO) was measured by the single breath method (SensorMedics 6200). a Exercise Capacity We measured functional exercise performance with a 6-minute walk test (6MWT). This test was performed in a 53-m hospital corridor. Encouragement was standardized. To avoid learning effects, the walking test was performed 2 times at the initial visit. 3 Results were expressed as a percentage of the predicted value. 17 We assessed maximal exercise capacity by maximal cycle ergometry (SensorMedics Vmax29C). a After 3 minutes unloaded pedaling, patients cycled at an incremental workload ( 10W/min) until symptom limitation. Ventilation and oxygen consumption (V O2 ) were continuously monitored. V O2 max was referred to normative values as proposed by Jones et al. 18 Ventilation and heart rate were referred to the measured maximal voluntary ventilation and maximum predicted heart rate, respectively. Health-Related Quality of Life We used the Chronic Respiratory Disease Questionnaire (CRDQ) to assess HRQOL. 19 This 20-item questionnaire scores HRQOL into 4 domains: dyspnea, mastery, emotional functions, and fatigue; it has been validated for the Dutch language by Gosselink et al. 20 Total CRDQ score was obtained by summation of the 4 above mentioned domains. Functional Status Functional status was measured with a Flemish translation of the Modified Pulmonary Functional Status and Dyspnea Questionnaire (PFSDQ-M). 21 This questionnaire has 30 items that assess both symptoms and change of activity levels in patients with pulmonary impairment. The activity domain evaluates the change in activity level based on their perception in performing 10 activities. The other 2 domains give separate scores for fatigue and dyspnea levels during these 10 activities. Higher scores indicate more impairment and higher level of dyspnea or fatigue. Emotional Distress To measure the psychologic impact of impairment and disability, we used the Hospital Anxiety and Depression Scale (HADS) to assess emotional distress. 22 The HADS consists of 14 items and has separate scores for anxiety (7 items) and depression (7 items). A score of 10 or greater on the HADS anxiety or depression scale suggests a clinically significant anxiety or depression. 22 Psychosocial Adjustment To measure the psychosocial impact of impairment and disability and possible adjustment to illness problems, we administered the Psychosocial Adjustment to Illness Scale Self- Report (PAIS-SR). 23 The PAIS-SR is a 46-item self-administered questionnaire and includes 7 domains; health care orientation, vocational environment, domestic environment, sexual relationships, extended family relationships, social environment, and psychological distress. A separate score for each domain was calculated by summation of the item scores. The total PAIS-SR score was calculated by summation of each domain score. High scores indicate more psychosocial impact and worse adjustment to illness. A score of less than 35 indicates successful adjustment to illness problems, 35 to 51 indicates moderate adjustment to illness problems, greater than 51 indicates a lack of adjustment to illness problems. 24 Social Support The Social Support List (SSL) evaluates social support received by the patients. 25 The SSL consists of 41 items and gives separate scores for positive social interactions (SSL-P) and negative social interactions (SSL-N). This questionnaire includes 6 domains of positive interactions of social support: (1) daily emotional interactions, (2) emotional support during problems, (3) appreciation, (4) material support, (5) social companionship, and (6) informative support. Negative interaction was scored separately. A total score of positive interactions was calculated by summation of the different domains. High scores indicate high social support. Score for negative interactions is obtained by summation of the item scores. High scores indicate more negative interactions. Sociodemographic Measurements Through a semi-structured interview, marital status, family composition, formal work activities, education level, current and former smoking status, the distance between patient s residence and the rehabilitation center, and the mode of transportation were recorded. Rehabilitation Program The 12-week rehabilitation program was administered as a multidisciplinary outpatient program. Caregivers active in this program were a pulmonary physician, physiotherapists, dietitian, psychologist, occupational therapist, nurse, and social assistant. Patients attended the 2-hour rehabilitation sessions 3 times a week. High-intensity exercise training (1.5h) consisted of cycling, treadmill walking, arm cycling, step exercise (60% of the maximal performance), and resistance training for upperand lower-limb muscle groups (70% of the 1-repetition maximum). Guidelines were available for all exercises to increase training intensity every week and are reported in detail elsewhere. 3 During the training sessions, patients were closely supervised and encouraged by physiotherapists. Oxygen saturation, heart rate, and Borg scores for dyspnea and fatigue were measured during the training sessions. If necessary, supplemental oxygen was given to maintain oxygen saturation above 90%. Based on the initial assessment, other interventions, such as occupational therapy, psychosocial interventions, and nutritional supplementation, were scheduled for 30 minutes every session as needed.

3 1790 PSYCHOSOCIAL CONDITIONS AND OUTCOME OF PULMONARY REHABILITATION, Trappenburg Statistical Methods All statistical analyses were performed using the SAS package. b All initial variables were related to predicted values, data were tested for normality, and means and standard deviations (SDs) were calculated. Paired t tests were used to analyze differences between the initial measurements and measurements after 3 months of rehabilitation. Either the Pearson or the Spearman rank correlation coefficient was used to determine the relationship between the psychosocial assessments and outcomes of rehabilitation depending on the distribution of the data. Rehabilitation outcome across sociodemographic groups was compared using analysis of variance testing or unpaired t test in case of dichotomous variables. Level of significance was set at.05. RESULTS Eighty-one patients entered the outpatient rehabilitation program, while 65 patients completed the 12-week program. Baseline physiologic characteristics of the rehabilitation group are shown in table 1. On the average, patients fell in stage II through IV of the Global Initiative for Chronic Obstructive Lung Disease scale and had impaired maximal and functional exercise capacity. Psychologic and sociodemographic parameters are summarized in table 2. HRQOL was markedly impaired, as can be concluded from the reduced CRDQ scores. The scores on the PFSDQ-M indicate that the majority of the studied group had a moderate change in functional status compared to the predisease state. 21 Twenty-five (38%) patients exhibited high levels of anxiety (HADS anxiety score 10) and 27 (42%) patients had significant depression (HADS depression score 10). The total score for the SSL-P indicates an average level of social support, compared with earlier studies. 25 Fifty-nine percent of the group had severe adjustment problems (PAIS-SR score 51), which means that the illness had a high impact on psychosocial adjustment. Baseline sociodemographic characteristics are summarized in table 3. The majority of the patients were married, and educational level was low on average. Half of the patients traveled independently from friends or family. Sixteen patients did not complete the program, because of lung transplantation (n 1), death (n 1), psychosocial problems (n 7), transportation problems (n 2), and comorbidity severely interfering with the rehabilitation (n 5). These patients had similar age, gender, pulmonary function, QOL, and psychosocial characteristics, but had significantly lower body mass index (22 6kg/m 2 vs 25 5kg/m 2, P.05) and lower maximal exercise capacity (48 16W vs 65 30W, P.02). Because no data on the effects of rehabilitation were available, these patients were not included in further analysis. The Table 1: Baseline Physiologic Characteristics Parameter Age (y) BMI (kg/m 2 ) FEV 1 (%pred) FVC (%pred) TLC (%pred) TLCO (%pred) 6MWT (%pred) Wmax (W) V O2 max (%pred) Mean SD Abbreviations: BMI, body mass index; %pred, percentage predicted; TLC, total lung capacity. Table 2: Baseline Psychologic and HRQOL Characteristics Parameter (Range) CRDQ Total score (20 140) Dyspnea (5 35) Emotion (7 49) Fatigue (4 28) Mastery (4 28) PFSDQ-M Activities (0 100) Dyspnea (0 100) Fatigue (0 100) HADS Anxiety (0 21) Depression (0 21) PAIS-SR Total score (0 138) SSL-P Total score (0 102) SSL-N Total score (0 21) Mean SD effects of the rehabilitation program are listed in table 4. After 3 months of rehabilitation, the group showed significant improvements in functional exercise capacity, maximal exercise capacity, HRQOL, functional status, depression, and anxiety. No improvements were found in measures of pulmonary function. Large individual variability in improvement of 6MWT, maximal workload, and HRQOL was observed. Univariate correlation analysis between the baseline psychosocial variables (HADS, PAIS, SSL-P, SSL-N) and the changes in outcome variables on exercise performance and QOL, revealed only a negative correlation for depression and Table 3: Baseline Sociodemographic Characteristics Characteristic Value Marital status Married 82 Divorced/widowed/single 18 Family composition Living alone 12 Living together 88 Educational level Primary/secondary education 71 Higher education/university 29 Travel Independent 52 Dependent on driver, own car 15 Dependent on driver, carpooling 17 Public traffic 12 Employment Blue collar working 59 White collar working 18 Independent profession 23 Smoking status Current 27 Former/never 73 Pack years (y) Distance to the rehab center (km) NOTE. Values are percentage or as otherwise indicated and mean SD.

4 PSYCHOSOCIAL CONDITIONS AND OUTCOME OF PULMONARY REHABILITATION, Trappenburg 1791 Table 4: Changes After Rehabilitation Parameter Change FEV 1 Liters Percentage MWT Meters Percentage Wmax Watts 6 12* Percentage 10 27* CRDQ Points PFSDQ-M Activities (points) 8 11* Dyspnea (points) 6 12* Fatigue (points) 4 8* HADS anxiety Points 2 3 HADS depression Points 3 3 NOTE. Values are mean SD. *P.01; P.001. change in absolute maximal workload (table 5). No other baseline measures were related to any of the outcome variables, and no significant difference in improvement related to the sociodemographic variables was observed. DISCUSSION The patients studied in the present trial had considerable impairment of physical and functional performance, psychologic problems (40%), average level of social support, and severe psychosocial adjustment problems (60%). The present study demonstrates that outcome of rehabilitation was independent of baseline psychologic and sociodemographic characteristics. Patients with depression and anxiety also responded to rehabilitation. Level of social support, marital status, family composition, level of education, mode of transportation, distance, and smoking status were not predictive for outcome of pulmonary rehabilitation. Some criticism of the results may be expressed. Selection of patients for rehabilitation was not random. By definition, only enrolled patients agreed to participate in the rehabilitation program. Patients who were not enrolled might have had more psychosocial problems and emotional distress, which discouraged them from starting the rehabilitation program. This bias might have resulted in selecting more motivated patients or patients with more appropriate coping style. We confirmed that age, smoking status, and gender did not significantly determine changes in exercise capacity and HRQOL. 7,9,10 Indeed, international guidelines state that current cigarette smokers are reasonable candidates for pulmonary rehabilitation and probably obtain benefits similar to nonsmokers or exsmokers. 10,26 Smoking cessation intervention is an obviously important component of the pulmonary rehabilitation process for smokers. 26 In contrast, Foy et al 27 showed similar results after a 3-month rehabilitation program but found that female participants had less added benefit in HRQOL after a long-term exercise program. In the present study, depression explained 8% of the variance in improvement of maximal workload. Similarly, in cardiac rehabilitation, depression has been reported to account for 9% of the variance in the change in aerobic capacity. 28 In contrast to our study, Withers et al 29 found that COPD patients with higher anxiety scores on the HADS at baseline showed larger improvements in exercise capacity following pulmonary rehabilitation. A possible explanation is that the latter study also found a relation between lower baseline exercise capacity and higher anxiety and depression scores. Psychosocial adjustment, functional status, and HRQOL were not significantly related to any change of the outcome variables. Wedzicha et al 30 found that improvement in exercise performance and HRQOL in patients with COPD after an exercise program was dependent on the initial degree of dyspnea. In the latter study, however, 2 different programs (home and outpatient) were used for severe and moderate dyspnoic patients, respectively, making the findings difficult to interpret. The multidisciplinary approach of this rehabilitation program may be an important factor in controlling the impact of less favorable psychosocial and sociodemographic conditions. In fact, exercise training has been shown to decrease the level of emotional distress in patients with COPD. 4 This is also demonstrated in the present study as the level of anxiety and depression significantly decreased. Moreover, the addition of psychotherapy to a pulmonary rehabilitation program showed more improvement in anxiety and depression. 5 Education, although not yet well investigated in rehabilitation, is part of most pulmonary rehabilitation programs, 31 and might be helpful for patients to cope with the physical and psychologic changes that occur with chronic illness. 32 Other studies show that teaching coping strategies improves HRQOL and psychosocial adjustment to illness. 33 The social worker of the rehabilitation team assisted to overcome practical problems such as transportation, financial and social problems. This multidisciplinary approach can decrease the potential disturbing concomitants during the rehabilitation progress. Although baseline psychologic and sociodemographic variables were not good predictors of outcome of rehabilitation, they have impact on adherence and compliance in patients with COPD. 15 Compliance to the training program has shown to be a factor contributing to the success of rehabilitation. Troosters et al 8 found that the number of sessions attended was significantly different between responders and nonresponders of rehabilitation. In the present analysis, factors potentially determining compliance did not affect the outcome of rehabilitation. This was probably due to the multidisciplinary approach described in the previous paragraph. CONCLUSIONS Irrespective of their psychologic and sociodemographic conditions prior to rehabilitation, patients with COPD can benefit from pulmonary rehabilitation. Symptoms of anxiety or depression, psychosocial adjustment problems or lack of social support per se are not exclusion criteria for a multidisciplinary Table 5: Correlations of Baseline Psychosocial Characteristics With Changes in Exercise Performance and QOL After Rehabilitation Characteristics Wmax 6MWD CRDQ HADS depression.34 (.008).16 (.23).18 (.18) HADS anxiety.20 (.12).07 (.61).08 (.55) PAIS total.24 (.10).08 (.57).09 (.56) SSL-P.05 (.69).06 (.68).13 (.35) SSL-N.15 (.28).04 (.78).16 (.26) NOTE. Values are r (P).

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