Measurement of short-term changes in dyspnea and disease-specific quality of life following an acute COPD exacerbation

STUDY OBJECTIVE: To determine whether currently available measurement tools can be used to obtain valid measurements of short-term changes in dyspnea and disease-specific quality of life (QOL) in outpatients with an acute COPD exacerbation. DESIGN: Prospective cohort study. METHODS: Sixty-six patients with an acute COPD exacerbation who presented to the emergency department completed the chronic respiratory disease index questionnaire (CRQ) and the baseline dyspnea index (BDI) and were discharged home receiving 10 days of medical therapy. Reassessment with the CRQ and the transitional dyspnea index (TDI) occurred within 48 h of relapse (defined as an urgent hospital revisit within 10 days because of worsening respiratory symptoms), or 10 days later if relapse did not occur. RESULTS: Patients who did not relapse (n = 49) showed moderate-to-large improvements in disease-specific QOL across all four CRQ domains (improvements in each domain of 1.4 to 1.9 U; p < 0.001 for all domains) and large positive changes in the TDI (total TDI score, + 5.02 plus minus 0.55 U; p = 0.0001). In contrast, patients who had a relapse (n = 17) did not have improved CRQ or TDI scores (mean negative change in three of four CRQ domains, total TDI score - 3.06 plus minus 1.14 U; p = 0.02). Changes in the CRQ dyspnea score and TDI correlated with each other (r = 0.78; p = 0.0001) and with changes in FEV(1) (CRQ, r = 0.48 and p = 0.0001; TDI, r = 0.46 and p = 0.0002). Ten control patients with stable COPD showed no changes in the CRQ or TDI over 10 days. CONCLUSION: The CRQ and BDI/TDI can be used to obtain valid, responsive measures of acute changes in QOL and dyspnea associated with a COPD exacerbation. The direction and magnitude of change in these scores was highly correlated with clinical outcome and with other health measures. Most outpatients treated for a COPD exacerbation experience significant short-term improvements in QOL and dyspnea, with the exception of patients who have a clinical relapse of symptoms.     

Effect of dynamic hyperinflation on exertional dyspnea, exercise performance and quality of life in COPD

There is increasing evidence that dynamic hyperinflation (DH) have negative effects on exercise performance and quality of life in chronic obstructive pulmonary disease (COPD) patients. The aim of this study was to investigate effect of dynamic hyperinflation on exertional dyspnea, exercise performance and quality of life in patients with COPD. 72 clinically stable patients with moderate to severe COPD and 30 healthy age-matched control subjects were included in this study. Pulmonary function tests including lung volumes and maximal respiratory muscle forces, arterial blood gas analyses, evaluation of exertional dyspnea with the Borg scale, and The Saint George Respiratory Questionnaire (SGRQ, Turkish version) were performed at rest and after a 6-min walk test. We measured the change in inspiratory capacity (AlphaIC) after exercise to reflect DH. 80% of patients with COPD significantly decreased IC after exercise (DH). AlphaIC were -0.27 +/- 0.26 L in COPD and 0.8 +/- 0.17 L in controls (p= 0.001). A stepwise multiple regression analysis showed that to be a patient with COPD, Basal Dyspnea Index (BDI) and AlphaIC were the best predictors of 6 MWD (r(2)= 0.53, p< 0.001). FEV1 added an additinal 9% to the variance in 6 MWD. Exertional dyspnea (AlphaBorg) correlated with AlphaIC (r= -0.44, p= 0.0001) and BDI (r= 0.34, p= 0.02). AlphaIC significantly correlated with symptom (r= -0.36, p= 0.008), activity (r= -0.31, p= 0.03) and total scores (r= -0.30, p= 0.04) of SGRQ. Dynamic hyperinflation can often occur during exersice in patients with COPD. Extent of dynamic hyperinflation could able to explain exercise capacity limitation, exercise dyspnea, and poor quality of life in patients with COPD.     

Inspiratory muscle training in patients with COPD: effect on dyspnea, exercise performance, and quality of life

OBJECTIVE: The aim of the study was to assess the effect of target-flow inspiratory muscle training (IMT) on respiratory muscle function, exercise performance, dyspnea, and health-related quality of life (HRQL) in patients with COPD. PATIENTS AND METHODS: Twenty patients with severe COPD were randomly assigned to a training group (group T) or to a control group (group C) following a double-blind procedure. Patients in group T (n = 10) trained with 60 to 70% maximal sustained inspiratory pressure (SIPmax) as a training load, and those in group C (n = 10) received no training. Group T trained at home for 30 min daily, 6 days a week for 6 months. MEASUREMENTS: The measurements performed included spirometry, SIPmax, inspiratory muscle strength, and exercise capacity, which included maximal oxygen uptake (VO(2)), and minute ventilation (VE). Exercise performance was evaluated by the distance walked in the shuttle walking test (SWT). Changes in dyspnea and HRQL also were measured. RESULTS: Results showed significant increases in SIPmax, maximal inspiratory pressure, and SWT only in group T (p < 0.003, p < 0.003, and p < 0.001, respectively), with significant differences after 6 months between the two groups (p < 0.003, p < 0.003, and p < 0.05, respectively). The levels of VO(2) and VE did not change in either group. The values for transitional dyspnea index and HRQL improved in group T at 6 months in comparison with group C (p < 0.003 and p < 0.003, respectively). CONCLUSIONS: We conclude that targeted IMT relieves dyspnea, increases the capacity to walk, and improves HRQL in COPD patients.     

Activity limitation and quality of life in COPD

Limitation of activity and impaired quality of life are important outcomes of COPD. There is an association between measures of self-reported physical activity and overall health status, and they appear to change together spontaneously over time and in response to treatment. The relationship between symptoms and activity limitation is complex, because activity can be limited entirely by symptoms, or impaired by symptoms so that it requires greater effort or causes discomfort. The patient has the choice of whether to restrict their activity or maintain it at the cost of having symptoms. In theory, this may make it difficult to produce reliable standardized assessments of activity limitation because it may not be clear exactly what is being measured. Analysis of items in the St George's Respiratory Questionnaire (SGRQ) concerned with activities that are either not possible due to breathlessness, or are a cause of breathlessness, show that they contribute to a unidimensional model of activity limitation in daily life and a unidimensional model of overall COPD-related health status. The items lie distributed evenly along the same severity continuum, from very mild to very severe, along with other items concerned with symptoms and the psycho-social impact of the disease. This suggests that self-reported limitation of activity may form a reliable construct, and may also provide a good surrogate marker of health status in COPD.     

A comparison of the level of dyspnea vs disease severity in indicating the health-related quality of life of patients with COPD

STUDY OBJECTIVES: To compare categorizations of the level of dyspnea with the staging of disease severity as defined by the FEV(1) in representing how the health-related quality of life (HRQOL) is distributed in patients with COPD. DESIGN: Cross-sectional study. SETTING: Outpatient clinic at the respiratory department of a university hospital. PATIENTS: A total of 194 consecutive male patients with stable, mild-to-severe COPD. MEASUREMENTS: The score distributions for the components of the St. George's respiratory questionnaire (SGRQ) were used as disease-specific HRQOL measures, and the scores from the Medical Outcomes Study Short Form 36-item questionnaire (SF-36) were used as generic HRQOL measures. These scores were stratified according to the level of dyspnea, as defined by the Medical Research Council (MRC) dyspnea scale, and the stage of disease severity, as defined by the American Thoracic Society (ATS). Differences in the HRQOL scores among the subgroups were compared by an analysis of variance (ANOVA). Multiple pairwise comparisons were made with Fisher's least significant difference (LSD) method, with the overall alpha-level set at 0.05. RESULTS: In those groups classified according to the level of dyspnea, significant differences were observed for the scores on the SGRQ and SF-36 (ANOVA, p < 0.05). The scores for activity and impact, and the total scores of the SGRQ and all scales, except for bodily pain and general health on the SF-36, were significantly worse for patients with severe dyspnea (MRC scale grades, 3, 4, and 5, respectively) than for those with moderate dyspnea (MRC grade level, 2; Fisher's LSD method, p < 0.05). Significant differences were recognized among the different stages of disease severity with respect to the scores from all scales of the SF-36, except for bodily pain, and all scores from the SGRQ (ANOVA, p < 0.05). However, differences in the scores on the SGRQ and SF-36 between patients with ATS stage II disease (FEV(1), 35 to 49% predicted) and stage III disease (FEV(1), < 35% predicted) were not statistically significant. CONCLUSIONS: Using the SGRQ and SF-36, the HRQOL of patients with COPD was more clearly separated by the level of dyspnea than by the ATS disease staging. In addition to the ATS disease staging, categorizations based on the level of dyspnea may be useful to clinicians in terms of the HRQOL of COPD patients.     

Exercise dyspnea in patients with COPD

Dyspnea, a symptom limiting exercise capacity in patients with COPD, is associated with central perception of an overall increase in central respiratory motor output directed preferentially to the rib cage muscles. On the other hand, disparity between respiratory motor output, mechanical and ventilatory response of the system is also thought to play an important role on the increased perception of exercise in these patients. Both inspiratory and expiratory muscles and operational lung volumes are important contributors to exercise dyspnea. However, the potential link between dyspnea, abnormal mechanics of breathing and impaired exercise performance via the circulation rather than a malfunctioning ventilatory pump per se should not be disregarded. Change in arterial blood gas content may affect dyspnea via direct or indirect effects. An increase in carbon dioxide arterial tension seems to be the most important stimulus overriding all other inputs from dyspnea in hypercapnic COPD patients. Hypoxia may act indirectly by increasing ventilation and indirectly independent of changes in ventilation. A greater treatment effect is often achieved after the addition of pulmonary rehabilitation with pharmacological treatment.     

The significance of health related quality of life for the evaluation of interventional measures in patients with COPD

Health related quality of life (HRQOL) is an important criterion for the evaluation of rehabilitation measures in patients with chronic obstructive pulmonary disease (COPD). The present paper reviews the current literature about the effects of pulmonary rehabilitation on the HRQOL of patients with COPD. The aim is to summarize critically methods, results and unanswered issues of the present research on the effects of pulmonary rehabilitation on HRQOL. The rehabilitation of patients suffering of COPD is mainly based on six types of interventions: 1. long-term oxygen therapy (LTO), 2. pharmacological management, 3. surgical therapy (bilateral reduction of lung volume), 4. physical therapy, 5. nutritional therapy (special diets), and 6. psycho-social interventions (e.g. psychotherapy, training and education). Thirty-one studies could be included in which HRQOL served as an outcome criterion for the rehabilitation of COPD patients. In 14 (45%) studies exclusively a disease-specific measure for the assessment of HRQOL was employed, while in 12 (39%) studies a generic instrument was applied. In the remaining five (16%) studies two ore more measures were used, whereas four of them combined a generic and a disease-specific method. The St. Georges Respiratory Questionnaire (SGRQ) und the Chronic Respiratory Disease Questionnaire (CRDQ) belonged to the group of the specific instruments, while among the generic measures the Sickness Impact Profile (SIP), the Nottingham Health Profile (NHP), the SF-36 and the Quality of Well-Being Scale (QWB) were most frequently used in COPD patients. The surgical bilateral reduction of lung volume, pharmacological therapy, upper extremities muscle training and psychological measures as single interventions proved to have persistent positive effects on the HRQOL. Several rehabilitation programs, composed of a wide variety of different interventions were effective in terms of HRQOL. On the other hand, at follow-up, the short-term positive effects had decreased in two of the three studies, where the rehabilitation took place exclusively in an inpatient setting. However, in three of four programs implemented in an outpatient setting, a persistent positive effect on HRQOL could be demonstrated. In conclusion from the as of yet available findings, we suggest for future studies to use only such measures of HRQOL which have been tested psychometrically in patients with COPD and to combine disease-specific and generic measures. In order to achieve lasting positive effects of rehabilitation on HRQOL, outpatient settings or ambulatory refreshment sessions following rehabilitation on an inpatient basis should be preferred.     

The relation between measures of health status and quality of life in COPD

Because quality of life (QoL) and health status (HS) scales contain different kinds of items and are shown not to be equivalent, there is a recommendation to use both types of scales. We investigated the relationship between either type of scale but focusing on the subscales of HS measures. A sample of chronic obstructive pulmonary disease (COPD) patients completed two QoL scales and two HS scales (BPQ and SGRQ), neuroticism, six-minute walk test and FEV1. Factor analysis revealed a two-factor structure (consistent with previous research), and showed that one type of HS subscale is different from QoL but another is equivalent to QoL. If total HS scores are used then it is valuable to include a QoL measure, but if HS subscales are reported, then these cover both latent variables, with the BPQ providing a clearer separation of the latent variables than the SGRQ.     

Palliative management of refractory dyspnea in COPD

COPD is a progressive illness with worldwide impact. Patients invariably reach a point at which they require palliative interventions. Dyspnea is the most distressing symptom experienced by these patients; when not relieved by traditional COPD management strategies it is termed “refractory dyspnea” and palliative approaches are required. The focus of care shifts from prolonging survival to reducing symptoms, increasing function, and improving quality of life. Numerous pharmacological and non-pharmacological interventions can achieve these goals, though evidence supporting their use is variable. This review provides a summary of the options for the management of refractory dyspnea in COPD, outlining currently available evidence and highlighting areas for further investigation. Topics include oxygen, opioids, psychotropic drugs, inhaled furosemide, Heliox, rehabilitation, nutrition, psychosocial support, breathing techniques, and breathlessness clinics.     

The influence of co-morbidity on health-related quality of life in asthma and COPD patients

This study examines the association between somatic co-morbidity and both general and disease-specific health-related quality of life (HRQoL) in patients with asthma and chronic obstructive pulmonary disease (COPD). A cross-sectional analysis was done among 161 COPD patients and 395 asthma patients, aged 40-75 years, recruited from general practice. In the total study population, 47% had no, 32% had one, and 21% had two or more somatic co-morbid conditions, with no significant differences between asthma and COPD patients. Co-morbidity appeared to be associated with poor disease-specific HRQoL in asthma [odds ratio (OR) = 2.08 (1.37-3.18)] and with poor general HRQoL in asthma [OR = 2.96 (1.93-4.53)] and COPD [1.81 (0.91-3.60)] patients. Poorest HRQoL was found in patients with more than one co-morbid condition. Cardiac disease and hypertension were associated with poor disease-specific HRQoL in asthma. Of all co-morbid conditions, musculoskeletal disorders were most strongly associated with poor general HRQoL. Cardiac disease was found to be associated with general and disease-specific HRQoL in asthma but not in COPD. In studies on patients with asthma or COPD aged 40-75 years, co-morbidity should be treated as a determinant of HRQoL.     

Depression in COPD �C management and quality of life considerations

Depression is common in COPD patients. Around 40% are affected by severe depressive symptoms or clinical depression. It is not easy to diagnose depression in COPD patients because of overlapping symptoms between COPD and depression. However, the six-item Hamilton Depression Subscale appears to be a useful screening tool. Quality of life is strongly impaired in COPD patients and patients’ quality of life emerges to be more correlated with the presence of depressive symptoms than with the severity of COPD. Nortriptyline and imipramine are effective in the treatment of depression, but little is known about the usefulness of newer antidepressants. In patients with milder depression, pulmonary rehabilitation as well as cognitive-behavioral therapy are effective. Little is known about the long-term outcome in COPD patients with co-morbid depression. Preliminary data suggest that co-morbid depression may be an independent protector for mortality.     

Functional capacity (dyspnea) and quality of life in patients with chronic obstructive lung disease (COPD): instruments of assessment and methodological aspects

Functional capacity (dyspnea) and quality of life are important criteria for the assessment of disease impact and treatment outcome in patients with chronic obstructive pulmonary disease (COPD). We will review measures for dyspnea and quality of life with particular emphasis on their methodological properties. Because asthma and COPD exhibit important differences and are therefore not comparable, we discuss only those measures which have been verified methodologically in patients with COPD. A critical review of current measures for dyspnea reveals at best an only fair association between perceived dyspnea and physiological lung function, sharing not more than 30% of common variance. Moreover, the affective state of the patients, their individual adaptation level and further psychological variables serve as mediators between lung function and perceived dyspnea. However, several valid and reliable measures for dyspnea are available for research and clinical practice. While the term "quality of life" is rather broad and unspecified, many researches in the field prefer the more restrictive term "health-related quality of life (HRQOL), that is the quality of life as affected by health status. The concept of HRQOL encompasses the impact of the individual's health on his or her ability to perform activities of daily living such as social role functioning, home management, social and family relationships, self-care, mobility, recreation and hobbies. In the past 15 years there has been an increasing body of literature on the measurement of HRQOL in patients with COPD. Several disease-specific and generic instruments for the use in COPD patients have been published. There is a growing consensus about the methodological criteria a given instrument has to fulfill. These are validity, sensitivity (for change) and reliability. They have to be tested in patients suffering from the illness for which the HRQOL instrument is planned to be applied in clinical studies or routine. The disease-specific instruments are supposed to be more sensitive to small therapeutically induced changes. However, the empirical results in patients with COPD are mixed and do not clearly favour disease-specific instruments. Lung function, dyspnea measures and exercise tolerance as well do not correlate strongly with HRQOL. Most associations cover only between 10% and 16% of shared variance. Exercise tolerance is not well associated with lung function but correlates better with HRQOL. Nowadays we can rely on several measures for dyspnea and HRQOL which have been thoroughly verified methodologically in COPD patients. However, some disease-specific and generic instruments exhibit substantial flaws, so that they need to be revised and it seems better not to use them at present. Many methodological and conceptual questions remain unanswered in the field indicating a strong need for more research.     

Effects of aging on sensation of dyspnea and health-related quality of life in elderly asthmatics

BACKGROUND AND AIMS: As the awareness of sensory stimuli is often impaired in older subjects, it has been hypothesized that the aging process may influence the perception of dyspnea. This study aimed at evaluating the aging-related difference in perception of spontaneously occurring dyspnea in adult asthmatics and at whether any such aging-related differences have an effect on the health-related quality of life (HRQOL). METHODS: 18 elderly asthmatics (EA) aged >65 years and 20 young asthmatics (YA) (age range 16-44 years) were recruited. In all subjects, 12-month asthma symptom score and respiratory function were recorded. Dyspnea was measured at rest by the Visual Analog Scale (VAS) and HRQOL by the St. George's Respiratory Questionnaire (SGRQ). RESULTS: Although the groups did not differ for FEV1% predicted, the EA showed lower VAS scores (9.9+/-19.8 mm vs 19.5+/-17.0, p<0.05). As regards HRQOL, only the "Symptom" section of SGRQ showed lesser impairment in EA. CONCLUSIONS: Aging is associated with blunted sensation of dyspnea. This only partly attenuates the disease-related impairment in quality of life, and other factors are presumed to counterbalance this effect.     

Use of medication and quality of life among patients with COPD

STUDY OBJECTIVES: To determine the medications prescribed to patients with chronic obstructive pulmonary disease (COPD) and their relationship to health-related quality of life (HRQL). METHODS: Cross-sectional study of 611 consecutive patients with stable, mild-to-severe COPD who attended at the respiratory service of a single hospital during a 1-year period. HRQL was evaluated using the St. George Respiratory Questionnaire (SGRQ) and the Short Form 36-item (SF-36) questionnaires. Linear regression analysis was used to determine the influence of the number or type of medication on the total SGRQ score, adjusting by disease severity and other relevant variables. RESULTS: Significant differences were observed among the number of drugs prescribed according to dyspnea levels, percentage of predicted FEV1 (FEV1%), SGRQ scores and some areas of SF-36. Fifty-nine percent of patients with an FEV1%>50% were prescribed inhaled corticosteroids (ICS). Those who took an ICS had a worse HRQL than patients with an FEV1%>50% who did not receive ICS. CONCLUSIONS: A relationship exists between the number of medicines prescribed to patients with COPD and their HRQL, measured by the total SGRQ score, after adjustment by severity of the disease. Within the group of patients who should not have been prescribed ICS, there are subgroups that might benefit from this medication.