Evaluation of the short-form 36-item questionnaire to measure health-related quality of life in patients with idiopathic pulmonary fibrosis

OBJECTIVE: To validate the use of the 36-item short-form questionnaire (SF-36) for measuring health-related quality of life (HRQL) in patients with idiopathic pulmonary fibrosis (IPF). DESIGN:: Observational data at a single point in time. SETTING:: A specialized outpatient respiratory clinic. PARTICIPANTS: Thirty-four patients (mean +/- SE age, 58.29 +/- 1.87 years) with IPF and no significant comorbidity. A matched control group for HRQL measurements was composed of 34 normal subjects (mean age, 58.00 +/- 1.89 years). MEASUREMENTS AND RESULTS: Dyspnea was measured by the baseline dyspnea index (BDI). Respiratory function evaluation included FVC, FEV(1), and resting arterial blood gases. IPF patients showed a mean BDI score of 5.21 +/- 0.46. The mean FVC and FEV(1) values were 62.41 +/- 2.96% and 66.41 +/- 3.33%, respectively. The mean PaO(2) was 67 +/- 2.51 mm Hg, and the mean PaCO(2) was 37 +/- 1. 05 mm Hg. Patients scored significantly worse than control subjects with respect to the SF-36 domains of physical functioning, physical role, general health perceptions, vitality, social functioning, emotional role, and mental health index. BDI scores were significantly correlated with five SF-36 components, and FVC and FEV(1) were significantly correlated with two SF-36 components. Significant negative correlations were found between arterial pH and four SF-36 domains. CONCLUSIONS: Patients with IPF have a significant impairment of HRQL in both physical and psychological functioning. Dyspnea is the most important factor influencing the quality of life in these subjects. The SF-36 questionnaire is a valid instrument to evaluate HRQL in IPF patients.     

Predictors of first-year survival in patients with advanced COPD treated using long-term oxygen therapy

Little evidence-based guidance is available to aid clinicians in determining short-term prognoses in very severe COPD patients. Therefore, the present study was designed to provide a prospective assessment (1) of the mortality rates and (2) whether the baseline measurements may be determinants of 1-year mortality in hypoxemic COPD patients receiving long-term oxygen therapy (LTOT). Seventy-eight clinically stable patients with advanced COPD treated using LTOT were enrolled in a prospective cohort study. Outcome variable: first-year mortality. Baseline measurements: categorical variables: age (<60 or > or = 60 years); gender; body mass index (<20 or > or = 20 kg/m(2)); fat-free mass (FFM) index (<16 [men] and <15 kg/m(2) [women]; baseline dyspnea index (BDI) (< or = 3 or >3); and corticosteroid use. Continuous variables: smoking history; lung function; FFM; fat mass; hemoglobin; hematocrit; arterial blood gases; forearm muscle strength; St. George's Respiratory Questionnaire (SGRQ); and comorbidity score. By the end of 1-year of follow-up, 12 patients (15.4%) had died. Kaplan-Meier curves showed that BDI < or = 3 was the only variable associated with higher mortality. Cox proportional hazards analysis revealed that lower PaO(2) and SpO(2), higher PaCO(2) and SGRQ scores were associated with reduced survival. In the multivariate analysis, BDI remained predictive of mortality (hazard ratio [HR], 0.50; 95% confidence interval [CI], 0.31-0.81), as did PaO(2) (HR, 0.49; 95% CI, 0.26-0.95). These data suggest that readily available parameters as dyspnea intensity and hypoxemia severity may be useful in predicting first-year survival rates in advanced COPD patients receiving LTOT.     

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.     

The evaluation of dyspnea and quality of life in COPD

Dyspnea defined as an uncomfortable sensation of breathing is the main cause of disability in chronic obstructive pulmonary disease (COPD) patients. There is evidence that the underlying mechanisms of dyspnea are multifactorial. The aim of this study was to investigate these mechanisms causing dyspnea in COPD patients and the relationship between functional parameters, dyspnea scales and quality of life questionnaire. For this purpose 56 patients (11 female, 45 male) were recruited. Pulmonary function tests including airflow rates, lung volumes, maximal respiratory muscle forces, diffusing capacity, breathing pattern, arterial blood gas analyses as well as dyspnea scales MRC, baseline dyspnea index (BDI) and The Saint George Respiratory Questionnaire (SGRQ) were performed. The overall group showed moderate obstructive disease (FEV1%= 59.02 +/- 3.30) and mild hypoxemia with some air trapping (RV/TLC%= 52.00 +/- 2.00). MRC scale did not show any significant correlation with pulmonary function parameters. There was significant positive correlation between BDI and airflow rates, PImax, DLCO and air trapping. Breathing pattern parameters (Ti/Ttot, VT/Ti) also correlated with BDI. There was positive correlation between PaO2 and BDI (p< 0.001). SGRQ scores correlated significantly with FEV1, PImax, RV/TLC and P 0.1. There was also strong correlation between BDI and SGRQ scores. In conclusion, dyspnea is the result of multiple factors such as airflow limitation, decreased respiratory muscle strength, changes breathing pattern, hypoxemia, and air trapping which in turn affects quality of life in patients with COPD.     

Both generic and disease specific health-related quality of life are deteriorated in patients with underweight COPD

This study evaluated the effects of body weight on both generic and disease-specific health-related quality of life (HRQoL) of patients with COPD. A total of 83 patients with stable COPD were enrolled (mean age: 74.6 yr, mean FEV1: 1.29 L). Patients were divided into two groups according to body mass index (BMI) (UW group: BMI < or = 20, NW group: 20 < BMI < or = 26). The degree of dyspnea and both disease-specific and generic HRQoL were compared between the two groups. An oxygen cost diagram (OCD) was used to assess the degree of dyspnea and St. George's Respiratory Questionnaire (SGRQ) and Medical Outcomes Study Short Form 36-item Questionnaire (SF-36) were used for HRQoL evaluation. The OCD was significantly lower in the UW group. Compared with the NW group, the UW group showed significant deterioration in the total score and three subscales of SGRQ. SF-36 also showed significantly worse scores for the parameters of physical functioning, role emotional, bodily pain, and general health. The results of stepwise multiple regression analysis showed that OCD, FEV1, %pred. BMI were independent variables in the total score on SGRQ. The results of stepwise multiple regression analysis also showed that OCD was an independent variable for four of eight components of SF-36, while BMI was three of eight components of SF-36. In conclusion, low body weight in patients with COPD is related to a worsening of dyspnea and deterioration of both generic and disease-specific HRQoL. The present results also indicate that nutritional intervention may be important for improving dyspnea and HRQoL in patients with COPD.     

Health-related quality of life and mortality in male patients with chronic obstructive pulmonary disease

To assess whether generic and specific health-related quality of life (HRQL) are independently associated with total and specific mortality in patients with chronic obstructive pulmonary disease (COPD), we followed until 1999 a cohort of 321 male patients with COPD, recruited in 1993-1994 at outpatient respiratory clinics. Baseline characteristics recorded under stable clinical conditions included forced spirometry, arterial blood gas tensions, dyspnea scales, 11 comorbid conditions, St. George's Respiratory Questionnaire (SGRQ), and SF-36 Health Survey. Vital status was assessed through reinterviews, the Mortality Register, and clinical records. Subjects who died (106) were older (69.8 versus 62.5 years) (p < 0.001), had lower body mass index (BMI) (25.4 versus 27.1) (p < 0.01), were more impaired in the clinical characteristics studied (%FEV(1), 34.0 versus 51.0) (p < 0.001), and had long-term oxygen therapy more frequently (31% versus 7%) (p < 0.001). Survival was shorter when worse HRQL was reported. SGRQ total and SF-36 physical summary scores were independently associated with total and respiratory mortality in Cox models, including age, FEV(1), and BMI. The total mortality-standardized hazard ratios for both HRQL measures were 1.3, whereas those for FEV(1) were 1.6. HRQL measures provide independent and relevant information on the health status of male patients with COPD. Their use should be considered for a more thorough evaluation and staging of patients with 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.     

Health-related quality of life measurement in patients with chronic respiratory failure

The improvement of health-related quality of life (HRQL) is an important goal in managing patients with chronic respiratory failure (CRF) receiving long-term oxygen therapy (LTOT) and/or domiciliary noninvasive ventilation (NIV). Two condition-specific HRQL questionnaires have been developed to specifically assess these patients: the Maugeri Respiratory Failure Questionnaire (MRF) and the Severe Respiratory Insufficiency Questionnaire (SRI). The MRF is more advantageous in its ease of completion; conversely, the SRI measures diversified health impairments more multi-dimensionally and discriminatively with greater balance, especially in patients receiving NIV. The SRI is available in many different languages as a result of back-translation and validation processes, and is widely validated for various disorders such as chronic obstructive pulmonary disease, restrictive thoracic disorders, neuromuscular disorders, and obesity hypoventilation syndrome, among others. Dyspnea and psychological status were the main determinants for both questionnaires, while the MRF tended to place more emphasis on activity limitations than SRI. In comparison to existing generic questionnaires such as the Medical Outcomes Study 36-item short form (SF-36) and disease-specific questionnaires such as the St. George's Respiratory Questionnaire (SGRQ) and the Chronic Respiratory Disease Questionnaire (CRQ), both the MRF and the SRI have been shown to be valid and reliable, and have better discriminatory, evaluative, and predictive features than other questionnaires. Thus, in assessing the HRQL of patients with CRF using LTOT and/or NIV, we might consider avoiding the use of the SF-36 or even the SGRQ or CRQ alone and consider using the CRF-specific SRI and MRF in addition to existing generic and/or disease-specific questionnaires.     

Assessment of health-related quality of life in patients with interstitial lung disease

STUDY OBJECTIVES: Health-related quality of life associated with interstitial lung disease has received little attention in clinical studies because there have been no validated methods for directly measuring it. We have assessed the validity of several generic and respiratory-specific quality-of-life instruments in patients with interstitial lung disease. DESIGN: Cross-sectional study. SETTING: Outpatient pulmonary clinic at a university referral center. PATIENTS: Fifty patients with interstitial disease such as idiopathic pulmonary fibrosis, sarcoidosis, hypersensitivity pneumonitis, and asbestosis. INTERVENTIONS: Patients were administered four quality-of-life questionnaires, the Medical Outcomes Study Short Form 36 (SF-36), the Quality of Well-being scale (QWB), the Chronic Respiratory Questionnaire (CRQ), and the St. George's Respiratory Questionnaire (SGRQ). Patients concomitantly underwent pulmonary function testing and performed a 6-min walk. Measurements and results: Validation of these instruments was based on testing an a priori hypothesis that worse quality-of-life scores should correlate with more severe physiologic impairment demonstrated by pulmonary function tests, exercise tolerance on the 6-min walk, and dyspnea scores. Our patients, on average, had a moderate degree of physiologic impairment and demonstrated moderately decreased quality-of-life scores. Scores from all four quality-of-life questionnaires correlated significantly with 6-min walk distance and dyspnea score. Scores from the SF-36, QWB, and SGRQ showed significant correlation with FVC, FEV(1), and diffusing capacity as well. The SF-36 and SGRQ consistently showed the strongest correlation with physical impairment. CONCLUSIONS: Our findings indicate that preexisting quality-of-life instruments can be applied to patients with interstitial lung disease and suggest that the SF-36 and the SGRQ, in particular, are sensitive tools for assessing quality of life in these patients. Future intervention studies of patients with interstitial lung disease should consider using these measures.     

Characteristics of a population of COPD patients identified from a population-based study. Focus on previous diagnosis and never smokers

OBJECTIVE: To identify factors associated with diagnosis and health-related quality of life (HRQL) impairment in chronic obstructive pulmonary disease (COPD) patients from a population-based epidemiological study. DESIGN AND PARTICIPANTS: This was an epidemiologic, multicenter, population-based study. Three hundred and sixty-three individuals diagnosed with COPD from a randomly general population sample of 4035 individuals aged 40-69 were included in the analyses. INTERVENTIONS: Forced spirometry was performed on eligible subjects, and the European Commission for Steel and Coal (ECSC) and the St. George's Respiratory Questionnaires (SGRQ) were completed. Logistic regression models were constructed to identify variables associated with the previous diagnosis of COPD and with COPD in never smokers. A multiple linear regression model attempted to identify variables influencing HRQL impairment. RESULTS: Only 79 (21.7%) COPD patients had been previously diagnosed. Disease severity based on FEV(1), worse SGRQ score, previous respiratory disease, as well as the presence of wheezing were significantly associated with previous diagnosis. Being a woman, older than 55, with previous respiratory disease and without expectoration or wheezing characterized COPD in never smokers. A worse HRQL was associated with chronic symptoms, especially dyspnea; and with older age, cardiac comorbidity and impairment in lung function. CONCLUSIONS: Diagnosis of COPD in the community is more likely in patients with worse lung function and HRQL, and wheezing is the symptom most strongly associated with a diagnosis of COPD. Women older than 55, with previous respiratory diseases, without respiratory symptoms and mild airflow obstruction constitute the majority of individuals with COPD who have never smoked. Chronic respiratory symptoms are strongly associated with impairment in HRQL.     

Are COPD patients with nocturnal REM sleep-related desaturations more prone to developing chronic respiratory failure requiring long-term oxygen therapy?

BACKGROUND: Nocturnal oxygen desaturations (NOD), especially during REM sleep, have been described in patients with COPD. However, the role of NOD in the evolution of COPD to chronic respiratory failure has not been well studied. OBJECTIVE: The aim of our study was to evaluate whether NOD is a risk factor for the development of chronic respiratory failure in COPD patients. METHODS: We studied 34 consecutive COPD patients with a stable daytime PaO(2) >60 mm Hg over a period of 42 months. We classified patients as desaturators (NOD) when episodic desaturations were found mainly during REM sleep, independently of baseline SaO(2) values. RESULTS: At enrollment 19 patients (55.8%) had NOD. Over the follow-up period, 10 patients (29.4%) were included in a long-term oxygen therapy (LTOT) programme (9 were desaturators). The LTOT was initiated a median time of 22 +/- 6.8 months after enrollment. Patients who were subsequently prescribed LTOT had lower values of FEV(1) at enrollment, with a higher degree of NOD and PaCO(2). Stable respiratory failure developed earlier in patients with NOD: the two enrollment curves for LTOT differed significantly (log-rank test 2.56, p = 0.005). PaCO(2), NOD and FEV(1) were statistically significantly associated, both in univariate and multivariate Cox proportional hazards analyses, with an increased risk of entering a LTOT programme. CONCLUSIONS: We conclude that NOD may represent an independent risk factor for the development of chronic respiratory failure in COPD patients with daytime PaO(2) >60 mm Hg. A larger study is needed to confirm the role of NOD in the natural history of COPD and subsequently to identify the most appropriate therapeutic approach.     

Health-related quality of life of persons with sarcoidosis

STUDY OBJECTIVES: To describe the health-related quality of life (HRQL) and mental health of persons with sarcoidosis, as well as to assess physician-patient agreement about the presence of sarcoidosis symptoms. DESIGN AND SETTING: Cross-sectional study at three university medical center outpatient pulmonary clinics. PATIENTS: One hundred eleven outpatients with sarcoidosis seen between March and July 2002. MEASUREMENTS: The HRQL of sarcoidosis patients was measured using generic and respiratory disease-specific forms (ie, Medical Outcomes Study 36-item short form survey [SF-36] and the St. George respiratory questionnaire [SGRQ], respectively). Depression was assessed using the Center for Epidemiologic Studies depression scale, and stress was assessed with the perceived stress scale four-item questionnaire. The kappa-statistic was calculated to compare physician-patient agreement in assessing sarcoidosis-related symptoms. RESULTS: Patients had moderate-to-severe reductions across all measured domains in perceived HRQL. Those patients who were prescribed oral corticosteroids had lower scores on both the SF-36 and the SGRQ than did those patients who were not. These differences were statistically significant and clinically important. The prevalence of depression was 66%, and that of significant stress was 55%. Spirometry values (FEV(1), 82% predicted; FVC, 86% predicted) were associated neither with HRQL nor with patients' perceived sarcoidosis symptoms, although they were correlated (r = 0.43; p < 0.0001) with physicians' perceptions that patients were symptomatic. Physicians and patients had only fair agreement (kappa-statistic range, 0.24 to 0.36 [by center]) in assessing perceived sarcoidosis symptoms. CONCLUSIONS: Outpatients with sarcoidosis had global reductions in measured HRQL and mental health indexes, although patients receiving therapy with oral corticosteroids had significantly worse HRQL. Experienced physicians based their assessments of patients' sarcoidosis symptoms on measures that were not related to issues of importance to patients. HRQL measurement may provide a unique insight into the impact that sarcoidosis may have on a patient's life that is not captured in traditional physiologic measures.     

Power of outcome measurements to detect clinically significant changes in pulmonary rehabilitation of patients with COPD

STUDY OBJECTIVES: Several validated instruments are used to measure outcomes, such as exercise performance, dyspnea, and health-related quality of life after pulmonary rehabilitation (PR) in patients with COPD. However, no study has simultaneously compared the responsiveness of the most frequently used outcome measurements after PR. We designed this study to investigate the capacity of several of the most frequently used outcome measurements to detect changes after PR in a population of patients with severe COPD who qualified for lung volume reduction surgery. DESIGN, PATIENTS, AND INTERVENTIONS: We evaluated 37 patients with severe COPD (FEV(1) < 40%) before and after 6 to 8 weeks of outpatient PR. The following frequently used tools were evaluated: the 6-min walk distance (6MWD); functional dyspnea with the Medical Research Council (MRC) scale; baseline and transitional dyspnea index (BDI/TDI); resting and 6MWD visual analog scale (VAS); quality of life with a generic tool (the Short Form-36 [SF-36]); and two disease-specific tools, the Chronic Respiratory Disease Questionnaire (CRQ) and the St. George's Respiratory Questionnaire (SGRQ). RESULTS: After PR, mean +/- SD 6MWD increased in 33 of 37 patients (89%), from 285 +/- 97 to 343 +/- 92 m (p = 0.009). Improvements were seen also in the MRC scale in 23 of 37 patients (62%; from 2.27 +/- 0.8 to 1.86 +/- 0.6; p = 0.01); in CRQ dyspnea in 25 of 37 patients (67%; from 3.25 +/- 0.9 to 3.90 +/- 1.4; p = 0.02); in CRQ mastery in 22 of 37 patients (60%; from 4.37 +/- 1.4 to 5.14 +/- 1.3; p = 0.01); and in BDI/TDI functional in 24 of 37 patients (64%; from 1.4 +/- 0.8 to 0.7 +/- 1.1; p = 0.002). There were smaller improvements in the SGRQ in 18 of 37 patients (48%) and in the SF-36 in 19 of 37 patients (51%), but they were not statistically significant. There were good correlations between the dyspnea components of all the tools. The 6MWD change did not correlate with the changes in the other outcomes. Clinically significant changes in the values for those outcome tools were detected in > 50% of patients for the BDI/TDI, 29% of patients for the MRC scale, in 37% of patients for the 6MWD, in 48% of patients for the VAS at peak exercise, in > 50% of patients for the CRQ, and in 40% of patients for the SGRQ. CONCLUSIONS: We conclude that the VAS peak exercise, BDI/TDI, and CRQ adequately reflect the beneficial effects of PR. The 6MWD evaluates a unique domain not related to quality of life. Due to their simplicity and sensitivity, VAS at peak exercise, 6MWD, and CRQ may be the best practical tools to evaluate responsiveness to PR.     

Relative responsiveness of the Chronic Respiratory Questionnaire, St. Georges Respiratory Questionnaire and four other health-related quality of life instruments for patients with chronic lung disease

BACKGROUND: Selection of heath-related quality of life (HRQL) instruments that are most responsive to changes in HRQL prevents investigators from drawing false-negative conclusions about the effectiveness of an intervention. The objective of this study was to compare the responsiveness of the Chronic Respiratory Questionnaire (CRQ), the St. Georges Respiratory Questionnaire (SGRQ) and four other HRQL instruments. METHODS: We enrolled 177 patients with chronic lung disease, primarily COPD (93%), who completed 8 weeks of respiratory rehabilitation. Patients completed the CRQ, the SGRQ and four generic measures (SF-36, Feeling Thermometer, Standard Gamble and Health Utilities index 3) at the beginning of the rehabilitation program and 12 weeks thereafter. We calculated standardized response means (SRMs) for each instrument, from the change score divided by the standard deviation of the change score. RESULTS: We observed the largest SRM for the CRQ (0.24-0.66 for the four CRQ domains on the interviewer-administered and 0.56-0.84 for the self-administered format) and the SGRQ (0.33-0.51 for the three SGRQ domains and total score). The CRQ dyspnea domain was statistically significantly more responsive than any other instrument including the SGRQ. For the SGRQ, the total and impacts domain were significantly more responsive than the generic and preference-based instruments. CONCLUSIONS: This study confirms that the CRQ and SGRQ are substantially more responsive than generic measures, and suggests particularly strong responsiveness for the self-administered CRQ.     

Dyspnea as clinical indicator in patients with chronic obstructive pulmonary disease

The aim of this study was to evaluate the relationship between dyspnea and functional, psychosocial and quality of life parameters among persons with chronic obstructive pulmonary disease (COPD). We conducted a cross-sectional study of 90 stable COPD patients recruited from a specialized respiratory clinic. Dyspnea was measured using the ATS-DLD-78 questionnaire modified dyspnea scale (1-5 scale). Physical and functional evaluation included spirometry and six minute walking tests. Subjects then completed five psychological questionnaires: the Coping Inventory for Stressful Situations, the State/Trait Anxiety Inventory, the Beck Depression Index, the NEO-Five Factor Personality Inventory, and the Interpersonal Relationships Inventory. Patients also completed two disease-specific health-related quality of life (HRQL) questionnaires: St. George's Respiratory Questionnaire (SGRQ) and Chronic Respiratory Questionnaire (CRQ). Subjects were predominantly male (n = 65) with a mean age of 68 years (+/- standard deviation 7.6). Over half (54%) the patients reported severe dyspnea (grade 5), and a quarter (24%) reported moderate dyspnea (grade 3-4). Mean FEV1 was 37.8 +/- 14.8% predicted. The mean total SGRQ score was 49 +/- 16 and the CRQ total score was 4.2 +/- 0.9. Dyspnea severity was associated with poorer HRQL scores and decreased physical performance. Based on linear regression, dyspnea scores--but not spirometric values--also correlated with indices of anxiety, depression, and neuroticism. Dyspnea correlated more strongly with HRQL and with indices of anxiety and depression than spirometric values. Although spirometry is often used to evaluate disease severity, dyspnea which is a patient centered outcome better reflect overall disease impact among COPD patients.     

Health-related quality of life in patients with chronic respiratory failure after long-term mechanical ventilation

STUDY OBJECTIVES: This study was aimed at assessing health-related quality of life (HRQL) in patients with chronic respiratory failure (CRF) and long-term survival following prolonged intensive care mechanical ventilation. DESIGN: Observational cohort study. SETTING: Patients with CRF who had been transferred to our specialized weaning centre due to prolonged mechanical ventilation (>14 days) and weaning failure. PATIENTS AND PARTICIPANTS: Out of 87 long-term survivors (>6 months), 73 patients (mean age: 60.3+/-13.6 years, chronic obstructive pulmonary disease (COPD, 43%), thoraco-restrictive (21%) or neuromuscular disorders (15%), various chronic diseases (22%)) returned the MOS 36-Item Short-Form Health Status Survey (SF-36) and the St. George's respiratory questionnaire (SGRQ). MEASUREMENTS AND RESULTS: The total ventilation time was 38.7+/-45.9 days. The time between discharge from ICU and HRQL assessment was 31.0+/-22.2 months. Physical health was markedly reduced compared to general population norm, but mental health was mildly impaired. HRQL was comparable to patients with stable CRF receiving non-invasive ventilation who did not need prolonged invasive MV. In addition, general HRQL was better in patients with restrictive respiratory disease compared to patients with neuromuscular diseases (P<0.05). Physiological parameters such as blood gases or lung function parameters were not correlated to any HRQL measurements. CONCLUSIONS: In patients with CRF surviving prolonged ventilation on ICU, the presence of CRF itself is the major determinant of HRQL. Here, the underlying cause of CRF is the major factor which determines the degree of HRQL impairment with patients suffering from restrictive ventilatory disorders reporting the best HRQL when compared to patients with COPD or neuromuscular diseases. Despite severe physical handicaps due to CRF mental health is only mildly compromised.     

Incidence of nocturnal desaturation while breathing oxygen in COPD patients undergoing long-term oxygen therapy

STUDY OBJECTIVE: It is suggested that oxygen flow be increased by 1 L/min during sleep in COPD patients undergoing long-term oxygen therapy (LTOT) in order to avoid nocturnal desaturations. The purpose of this study was to investigate the occurrence of nocturnal desaturations while breathing oxygen in COPD patients receiving LTOT. SETTING: Inpatient/university hospital. PATIENTS: We studied 82 consecutive COPD patients. Their functional characteristics were as follows (mean +/- SD): FVC, 2.15 +/- 0.69 L; FEV(1), 0.87 +/- 0.33 L; PaO(2), 51.6 +/- 5 mm Hg; and PaCO(2), 47 +/- 8 mm Hg. MEASUREMENTS: Overnight pulse oximetry (PO) was performed twice: (1) while breathing air and (2) while breathing supplemental oxygen assuring satisfactory diurnal resting oxygenation (mean PaO(2) during oxygen breathing, 67 +/- 6 mm Hg; mean arterial oxygen saturation [SaO(2)] during oxygen breathing, 93%). RESULTS: PO performed while patients were breathing air showed a mean overnight SaO(2) of 82.7 +/- 6.7%. Patients spent 90% of the recording time with an SaO(2) of < 90%. While breathing oxygen, 43 patients (52.4%) remained well oxygenated. Their mean overnight SaO(2) while breathing oxygen was 94.4 +/- 2.1%, and time spent with saturation < 90% was 6.9 +/- 8.6%. Thirty-nine patients (47.6%) spent > 30% of the night with an SaO(2) of < 90% while breathing supplemental oxygen. Their mean overnight SaO(2) while breathing oxygen was 87.1 +/- 4.5%, and time spent with an SaO(2) of < 90% was 66.1 +/- 24.7% of the recording time. Comparison of ventilatory variables and daytime blood gases between both groups revealed statistically significantly higher PaCO(2) on air (p < 0.001) and on oxygen (p < 0. 05), and lower PaO(2) on oxygen (p < 0.05) in the group of patients demonstrating significant nocturnal desaturation. CONCLUSIONS: We conclude that about half of COPD patients undergoing LTOT need increased oxygen flow during sleep. Patients with both hypercapnia (PaCO(2) > or = 45 mm Hg) and PaO(2) < 65 mm Hg while breathing oxygen are most likely to desaturate during sleep.     

Persistent hypoxemia and excessive daytime sleepiness in chronic obstructive pulmonary disease (COPD)

Fourteen patients with chronic obstructive pulmonary disease (COPD) and chronic hypoxemia were studied to evaluate the relationship between hypoxemia and objective and subjective daytime sleepiness. Patients were selected with a waking PaO2 of less than 70 mm Hg and less than 50 percent predicted FEV1. Clinically, none of these patients had complaints of significant daytime sleepiness. Each patient underwent standard all-night polysomnographic evaluation followed by a multiple sleep latency test (MSLT). There was no significant correlation between the mean sleep onset latency for the MSLT and the waking PaO2, PCO2, FEV1, or spontaneous desaturations during sleep. Patients with COPD exhibited a mean MSLT that was within normal limits, despite a short total sleep time and numerous arousals from sleep. We conclude that there appears to be no relationship between chronic daytime hypoxemia and subjective reports and objective measures of daytime sleepiness.