Abstract
Background: Symptoms of anxiety, depression and exercise intolerance contribute to an impaired health status in patients with Chronic Obstructive Pulmonary Disease (COPD). Coping styles may also be related to symptoms and health status. Objectives of this study were to assess the distribution of coping styles in patients entering pulmonary rehabilitation (PR) with and without anxiety and/or depression; and to assess whether coping styles contribute to exercise intolerance and reduced health status. Methods: Coping styles were studied in 698 patients using the Utrecht Coping List (UCL). Disease-specific health status (St. George's Respiratory Questionnaire, SGRQ), anxiety and depression (Hospital Anxiety and Depression Scale, HADS), exercise tolerance (6-minute walking distance, 6MWD) and clinical characteristics were assessed. Results: High levels (16.5%) of active confronting coping style were rarely reported. A minority of patients used low levels (17.5%) of passive reaction pattern coping style. Differences in coping profiles were present between patients with and without anxiety and/or depression. A higher level of active confronting coping style was associated with a higher 6MWD (Beta 0.092, p < 0.01), while a higher level of avoidance coping style was associated with a lower 6MWD (Beta -0.074, p = 0.017). The UCL subscales were not related to SGRQ total score (p > 0.05). Conclusions: In COPD patients entering PR, coping styles were associated with symptoms of anxiety, depression and exercise intolerance, but not associated with disease-specific health status. Future studies should examine whether interventions aiming at optimizing coping styles during PR can improve outcomes for patients with COPD.
Introduction
Chronic Obstructive Pulmonary Disease (COPD) is an important cause of morbidity and mortality worldwide, and in turn, a major public health problem. COPD is defined as a progressive chronic inflammatory condition of the lungs, characterized by airflow limitation which is not completely reversible (Citation1). Although dyspnea, wheezing, chronic coughing and sputum are the main respiratory symptoms, skeletal muscle weakness and exercise intolerance are important extra-pulmonary features of COPD (Citation2–4).
Patients with COPD may also experience psychological disturbances such as anxiety and depression, low self-efficacy, decline in cognitive functioning and coping difficulties (Citation5, 6). Coping is defined as a combination of constantly changing behavioral and/or cognitive efforts to manage situational demands which are the result of a person's confrontation and evaluation of a stressor (Citation7). Patients’ coping with daily symptoms and limitations may have more influence on important patient-centered outcomes (i.e., exercise intolerance and health status) than the impaired lung function (Citation8). To date, this has not been confirmed. Therefore, the relationship between coping styles, exercise intolerance and disease-specific health status in patients with COPD remains unknown.
Previously, a coping style associated with withdrawal was correlated with higher levels of anxiety and depression and a reduced disease-specific health status in patients with COPD (Citation6). Moreover, the relationship between symptoms of anxiety and/or depression and an impaired disease-specific health status has been established in COPD (Citation5). Therefore, symptoms of anxiety and depression need to be considered as possible confounding variables of the relationship between coping styles and health status.
Medical care for patients with chronic illnesses nowadays emphasizes on patient-centered care provided by interdisciplinary teams, which involves self-management education and shared decision making (Citation9). For example, pulmonary rehabilitation (PR) is designed to reduce symptoms and to improve functional status and independence in patients with COPD, by offering a patient-tailored interdisciplinary program focusing on physical, psychological and social functioning (Citation10). It may be important that members of the PR team consider patient's individual coping style.
The aims of the present cross-sectional observational study were to assess the distribution of coping styles in COPD patients with and without clinically relevant symptoms of anxiety and depression entering PR; and to assess whether and to what extent coping styles contribute to exercise intolerance, as well as to disease-specific health status. We hypothesized a priori that the distribution of coping styles differs among patients with and without clinically relevant symptoms of anxiety and/or depression. Furthermore, we hypothesized that coping styles of patients with COPD entering PR are related to exercise intolerance and disease-specific health status.
Methods
Design
A cross-sectional observational study was used to assess the distribution of coping styles in COPD patients with and without clinically relevant symptoms of anxiety and depression entering PR.
Patients
Patients with mild-to-very-severe COPD, admitted between January 2005 and December 2009 to CIRO+, a center of expertise for chronic organ failure (Horn, the Netherlands) for a comprehensive interdisciplinary PR program were included in this study (Citation11). The diagnosis of COPD was based on the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria (Citation12). Ethical approval was not indicated because all of the tests were done as part of the clinical routine and retrospectively analyzed. The institutional board of directors of CIRO+, Horn, the Netherlands reviewed and approved the use of patients’ records, data analysis and reporting for the study.
Instruments
As part of the clinical routine, the following parameters were assessed before start of PR: demographics; exercise tolerance (6-minute walking distance (6MWD) (Citation13)); arterial blood gases; body composition (body-mass index (BMI) and fat-free mass index (FFMI) (Citation14)); dyspnea (Medical Research Council dyspnea scale (MRC) (Citation15)) and co-existing morbidities (Charlson co-morbidity index (Citation16)). Furthermore, pulmonary function was assessed using spirometry (Masterlab®, Germany). Post-bronchodilator forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC) were calculated from the flow-volume curve and were expressed as percentage of reference values (Citation17).
Coping Styles
The Utrecht Coping List (UCL) was used to assess coping styles (Citation18). It represents a generic measure of coping applicable to stressors in general or to a given situation (Citation18). The UCL consists of 47 items describing a specific coping behavior, divided in seven subscales: active confronting, palliative reaction, avoidance, seeking social support, passive reaction pattern, expressing emotions and reassuring thoughts (see online supplement for details). Response options for each item are: ‘seldom or never’ (1 point), ‘sometimes’ (2 points), ‘often’ (3 points) and ‘very often’ (4 points). Mean total scores are calculated for every subscale. A higher score indicates an increased tendency towards using that specific coping style. Furthermore, scores are categorized in: very low, low, medium, high, or very high; based on Dutch norm scores, which are calculated for men and women in different age categories (Citation18).
Symptoms of Anxiety and Depression
The Hospital Anxiety and Depression Scale (HADS) was used to evaluate the presence of symptoms of anxiety and/or depression (Citation19). The HADS is a self-administered questionnaire, consisting of 14 items divided into two subscales: anxiety (HADS-A) and depression (HADS-D). Scores for both subscales range from 0 (optimal) to 21 (worst) points. A score equal to or greater than 10 represents the presence of clinically relevant symptoms of anxiety or depression (Citation19). The HADS was used frequently among COPD patients undergoing PR (Citation5).
Disease-specific Health Status
Disease-specific health status was assessed using the self-administered St. George's Respiratory Questionnaire (SGRQ) (Citation20). A total score and three domain scores (symptoms, activity and impact) are provided. Scores range from 0 (best) to 100 points (worst).
Statistics
Data were analyzed using SPSS 17.0 (SPSS Inc. Chicago, IL). Continuous variables were tested for normality and are presented as mean and standard deviation (SD). Categorical variables were described as frequencies. Independent sample t-tests were used to study differences in mean UCL subscales scores between patients with and without symptoms of anxiety and/or depression. For the assessment of possible differences in coping profiles between patients with and without symptoms of anxiety and/or depression, two linear regression models using forced entry method were developed. For the first model, the mean UCL subscale scores were entered as dependent variables, while the HADS-A score (<10 points or ≥10 points), age, sex, FEV1, MRC and 6MWD were entered as independent variables. Model two only differs in the use of HADS-D score instead of HADS-A score.
Forced entry linear regression analysis was also used to assess the relationship between coping styles and exercise intolerance. The 6MWD was entered as dependent variable and the seven mean coping subscale scores were entered as independent variables. Additionally, the following variables that showed bivariate correlation with 6MWD (Pearson correlation coefficient >0.30) were also entered as independent variables: age, sex, MRC dyspnea scale, FEV1, BMI, FFMI, SGRQ total score, HADS-A score and HADS-D score.
Furthermore, to study the relationship between coping styles and disease-specific health status, we developed a linear regression model using forced entry method with the SGRQ total score as dependent variable and the seven mean coping subscales as independent variables. The 6MWD, FEV1, MRC dyspnea scale, HADS-A score and HADS-D score showed bivariate correlation with SGRQ total score and were also entered as independent variables. The following variables did not show bivariate correlation with SGRQ total score and were not included in the final model: sex, age, Charlson comorbidity index score, BMI and long-term oxygen therapy. All tests were two tailed with alpha set at p < 0.05 (Citation21).
Results
General Patient Characteristics
We included 698 patients (GOLD stage I and II, 280 patients (40.1%); GOLD stage III, 275 patients (39.4%); GOLD stage IV, 143 patients (20.5%)). In general, patients had a normal BMI and FFMI; an impaired exercise tolerance; and an impaired disease-specific health status (). Clinically relevant symptoms of anxiety were reported by 209 patients (29.9%), while clinically relevant symptoms of depression were reported by 162 patients (23.3%).
Table 1. General patient characteristics.
Coping Styles
High levels of active confronting coping style were reported by 16.5% of the patients (). Furthermore, about half of the patients reported medium levels of: palliative reaction, seeking social support, and/or reassuring thoughts coping styles. Additionally, most patients used a medium (38.5%) or high (43.9%) levels of passive reaction pattern coping style.
Figure 1. Distribution of UCL coping styles in COPD patients entering PR. Proportion of patients using a very low, low, medium, high or very high level of coping style.
Coping Styles and Symptoms of Anxiety
Statistically significant differences were found between patients with and without clinically relevant symptoms of anxiety in the following UCL coping styles: active confronting, palliative reaction, avoidance, passive reaction pattern and expressing emotions coping style (all p < 0.0005). This was confirmed by linear regression analysis after adjusting for age, sex, FEV1, MRC and 6MWD (). Indeed, patients with symptoms of anxiety reported a lower use of active confronting style (Beta = –0.177, p < 0.0005) and an increased use of palliative reaction (Beta = 0.131, p = 0.001), avoidance (Beta = 0.136, p < 0.0005), passive reaction pattern (Beta = 0.474, p < 0.0005) and expressing emotions (Beta = 0.177, p < 0.0005) coping styles. Mean UCL scores of seeking social support (Beta = –0.001, n.s.) and reassuring thoughts (Beta = 0.033, n.s.) coping styles were comparable for patients with and without clinically relevant symptoms of anxiety (p > 0.05).
Figure 2. UCL subscale scores of patients with and without symptoms of anxiety. Data are presented as mean (standard deviation, SD). #p < 0.0005, based on independent sample t-test; *p ≤ 0.001, based on linear regression analysis, adjusted for age, sex, FEV1, MRC and 6MWD. Abbreviations: FEV1: forced expiratory volume in the first second; MRC: Medical Research Council; 6MWD: 6-minute walking distance; HADS-A: Hospital Anxiety and Depression Scale, anxiety subscale.
Coping Styles and Symptoms of Depression
Mean UCL coping style scores of: active confronting, avoidance and passive reaction pattern coping style were statistically significant different between patients with and without clinically relevant symptoms of depression, as assessed by independent sample t-tests (all p < 0.0005). This was confirmed by linear regression analysis after adjusting for age, sex, FEV1, MRC and 6MWD (). Patients with symptoms of depression reported a lower use of active confronting coping style (Beta = –0.163, p < 0.0005) and an increased use of avoidance (Beta = 0.134, p = 0.001) and passive reaction pattern (Beta = 0.397, p < 0.0005) coping styles. Additionally, patients with symptoms of depression reported lower levels of seeking social support coping (Beta = –0.083, p = 0.04) than patients without symptoms of depression.
Figure 3. UCL subscale scores of patients with and without symptoms of depression. Data are presented as mean (standard deviation, SD). # p < 0.0005, based on independent sample t-test; * p < 0.05, based on linear regression analysis, adjusted for age, sex, FEV1, MRC and 6MWD. Abbreviations: FEV1: forced expiratory volume in the first second; MRC: Medical Research Council; 6MWD: 6-minute walking distance; HADS-D: Hospital Anxiety and Depression Scale, depression subscale.
See online supplement for distribution of UCL coping styles of patients with COPD, stratified for clinically relevant symptoms of anxiety and/or depression.
Coping Styles and Exercise Intolerance
Several coping styles showed a relationship with 6MWD, after controlling for sex, age, MRC, FEV1, BMI, FFMI, SGRQ total score, HADS-A score and HADS-D score (). A higher level of active confronting coping style was associated with a higher 6MWD, while a higher level of avoidance coping style was associated with a lower 6MWD. This linear regression model explained 51.2% of the variance in 6MWD.
Table 2. The relationship of UCL coping styles with 6MWD: linear regression model
Coping Styles and Disease-specific Health Status
Coping styles were not related to SGRQ total score after adjusting for FEV1, 6MWD, MRC dyspnea scale, HADS-A score and HADS-D score (). However, 6MWD, MRC dyspnea score, HADS-A score and HADS-D score were associated with disease-specific health status, explaining 48.2% of SGRQ total score. Excluding non-significant independent variables from both models above, did not change the models significantly (see online supplement, Table E3 and Table E4).
Table 3. The relationship of UCL coping styles with SGRQ total score: linear regression model
Discussion
Key Findings
The present study shows that only a minority of the COPD patients entering PR uses a high or very high level of active confronting coping style. Also, a minority of patients uses a very low or low level of passive reaction pattern coping style. Furthermore, patients with and without symptoms of anxiety and/or depression reported different coping profiles. Finally, coping styles are related to exercise intolerance, but not to disease-specific health status.
Coping Styles and Symptoms of Anxiety and/or Depression
The present study shows differences in coping profiles among COPD patients entering PR with and without clinically relevant symptoms of anxiety and/or depression. In fact, patients with symptoms of anxiety and/or depression reported a lower use of active confronting coping style and an increased use of avoidance and passive reaction pattern coping style than patients without symptoms of anxiety and/or depression. Studies including patients with rheumatoid arthritis and patients with chronic pain showed that the use of an active confronting coping style was associated with a higher life satisfaction, higher levels of daily functioning and psychological well-being, and better adjustment to the condition with a lower level of depression or helplessness (Citation7, Citation22–24). In patients with COPD hospitalized for an acute exacerbation was shown that a passive reaction pattern coping style and avoidance coping style were used more frequently by patients with psychological distress (Citation25). In addition, Scharloo and colleagues showed that a passive reaction pattern style is an important determinant of mental health (Citation26). Previous study demonstrated that patients with COPD who frequently used catastrophic withdrawal coping strategies experienced a higher level of anxiety and depression (Citation6). Our study, in the context of these prior studies shows the relationship of coping styles with psychological distress in patients with COPD entering PR.
Coping Styles and Exercise Intolerance
The present study shows that not only patient characteristics like age, dyspnea, lung function, body composition and disease-specific health status are determinants of exercise intolerance, but also coping styles. Indeed, a higher level of active confronting coping style is positively related to exercise tolerance, while higher levels of avoidance coping style are associated with increased impairment in exercise tolerance. This may be explained by the fact that the use of an active confronting coping style is related to higher self-esteem, life satisfaction and compliance with medical advice, whereas avoidance coping style refers to poorer physical functioning in terms of depression, well-being and functional disability (Citation24).
Coping Styles and Disease-specific Health Status
In contrast to our hypothesis, coping styles were not associated with disease-specific health status, after adjusting for FEV1, 6MWD, MRC dyspnea scale and HADS scores. Previously, Buchi and colleagues showed no relationship between coping styles, as assessed with the Freiburg Coping Questionnaire, and generic health status in COPD patients attending PR (Citation27). Nevertheless, McCathie showed a relationship between coping styles and disease-specific health status in outpatients with COPD (Citation6).
This disparity might be explained by the use of different instruments to assess coping styles. For example, McCathie and colleagues assessed coping styles using the Coping with Illness Questionnaire (Citation6). Furthermore, Scharloo and colleagues, showed a relationship between coping styles and generic health status, as assessed with Medical Outcomes Study SF-20 (Citation28). Moreover, in these studies symptoms of anxiety and depression were not taken into account as possible confounding variables of the relationship between coping styles and health status.
This may contribute to the fact that in the present study no relationship was found between coping styles and health status. It is also possible that differences in coping profiles exist between COPD patients entering PR and COPD outpatients. In fact, a previous study reported a difference in the use of coping styles between COPD outpatients and COPD patients who were hospitalized (Citation29). The COPD outpatients used predominantly optimistic, supporting and confronting coping styles, described as healthy coping styles, while hospitalized patients relied on fatalistic, palliative and supporting coping styles, described as both –healthy and less healthy coping styles (Citation29).
Clinical Implications
PR has been shown to improve disease-specific health status, exercise tolerance, dyspnea, symptoms of anxiety and depression and patients’ control over their disease (Citation30). Despite these benefits, part of the eligible patients declines participation or drops out during the program (Citation31). Moreover, the long-term outcome of PR may be predicted by coping styles (Citation27). Coping styles may be a target for interventions during PR. In fact, interventions can optimize coping styles. For example, a systematic review showed that self-management education interventions were able to improve coping styles of patients with rheumatoid arthritis (Citation23).
These interventions included: group sessions aimed at stimulating active confronting coping by teaching self-management skills or skills in dealing with stress; education support groups providing a climate for emotional support and recommendations on coping and self-treatments; and cognitive-behavioral therapy training coping strategies and improving skills in cognitive, emotional and behavioral dealing with the disease (Citation23).
Self-management education interventions are largely based on the principles of patient's cognitions and behavioral change with the aim to stimulate the patient's active participation in disease management (Citation32). Coping styles may be important factors to consider in self-management interventions. However, interventions targeting coping skills and behavior change are not routinely carried out in the current practice of PR (Citation33). Including coping interventions may be important for the best current disease control, as well as for future risk reduction of exacerbations, hospitalization, and the long-term consequences of COPD (Citation34). Future studies are needed to examine whether interventions aiming at optimizing coping styles during PR can improve outcomes for patients with COPD.
Limitations
Several methodological issues should be considered in interpreting the results of this study. First, the present study is a cross-sectional study and therefore does not allow conclusions about causal pathways between symptoms of anxiety and depression, exercise intolerance, and coping styles in patients with COPD. Hence, longitudinal studies are necessary to confirm the present findings. Second, we have chosen the UCL to assess coping styles. However, a variety of coping questionnaires is available (Citation6, 7, Citation18). The UCL was previously applied in COPD outpatients, and has shown satisfactory psychometric properties in a Dutch population (Citation18, Citation26). Other instruments define different coping styles categories and the use of another instrument might have changed our results. Third, multiple instruments exist for assessment of symptoms of anxiety and/or depression. We used the HADS, a well validated instrument frequently used in patients with COPD. However, the choice of the instrument might have influenced our results. Forth, the present study has only included COPD patients entering PR, which may limit the external validity of the present findings. It remains unknown whether and to what extent coping styles of patients with COPD entering PR are comparable with coping styles of patients with COPD who were not referred to, or refused PR. Nevertheless, insight into the coping styles of COPD patients entering PR might provide further directions for development of a patient-tailored PR program. Finally, the current findings need to be interpreted in the light of the number of comparisons that were made in the present study. Nonetheless, multiple findings in the same direction, rather than a single statistically significant result, suggest that these are not due to chance alone.
Conclusions
Most patients with COPD entering PR report a very low or low level of active confronting coping style and/or a medium, high or very high level of passive reaction pattern coping style. Coping profiles are different among COPD patients entering PR with and without clinically relevant symptoms of anxiety and/or depression. Finally, coping styles have a relationship with exercise intolerance, but are not related to disease-specific health status. Therefore, it is important to pay attention to coping styles in COPD patients entering PR. Future studies are warranted to examine whether interventions aiming at influencing coping styles can improve patient's coping and thereby, symptoms of anxiety, depression and exercise intolerance.
Declaration of Interest Statement
No financial or other potential conflicts of interest exist in any of the authors with respect to the subject of this manuscript. No grant was received for carrying out this research work. The authors are responsible for the content and the writing of this paper.
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