Impaired Sleep Reduces Quality of Life in Chronic Obstructive Pulmonary Disease

Disturbed sleep is reportedly common in chronic obstructive pulmonary disease (COPD), but the impact of quality of sleep on health-related quality of life (HRQL) has not been previously investigated in these individuals. The purpose of this study was to assess the impact of quality of sleep on HRQL in patients with COPD. In 30 clinically stable patients with moderate to very severe COPD, we evaluated subjective sleep quality using the Pittsburgh Sleep Quality Index (PSQI) and HRQL using the Saint George’s Respiratory Questionnaire. Additionally, lung function was assessed by spirometry, severity of dyspnea by the Modified Medical Research Council scale, and functional exercise capacity by the Six-Minute Walk Test. Twenty-one (70%) patients showed poor quality of sleep (PSQI > 5). HRQL was significantly correlated with quality of sleep (P = 0.02), post-bronchodilator FEV1 (P = 0.04), and severity of dyspnea (P < 0.01). Multiple regression analysis showed that quality of sleep was the best predictor of quality of life in our subjects. Our data suggest that quality of sleep is major determinant of HRQL in COPD. Increased efforts to diagnose and treat sleep problems, including measures to improve factors that adversely affect sleep should receive great attention in the daily management of these patients.     

Pulmonary Rehabilitation Improves Sleep Quality in Chronic Lung Disease

Abstract

Sleep-related disorders are common in patients with chronic obstructive pulmonary disease (COPD) and, possibily, other lung disorders. Exercise has been shown to improve sleep disturbances. In patients with COPD, pulmonary rehabilitation (PR) produces important health benefits with improvement in symptoms, exercise tolerance, and quality of life. However, the effect of PR on sleep quality remains unknown. The aim of this observational study was to evaluate sleep quality in patients with chronic lung disease and the role of PR as a non-pharmacologic treatment to improve sleep. Sixty-four patients with chronic lung disease enrolled in an 8-week comprehensive PR program, and completed the study (48% male; obstructive [72%], restrictive [20%], mixed [8%]; 44% on supplemental oxygen). Baseline spirometry [mean (SD)]: FEV₁% pred = 48.9 (17.4), FVC% pred = 72.5 (18.1), and FEV₁/FVC% = 53.1 (18.9). Exercise tolerance and questionnaires related to symptoms, health-related quality of life (HRQL), and sleep quality using the Pittsburgh Sleep Quality Index (PSQI) were obtained before and after PR. 58% reported poor sleep quality (PSQI > 5) at baseline. Sleep quality improved by 19% (p = 0.017) after PR, along with significant improvements in dyspnea, exercise tolerance, self-efficacy, and HRQL. Sleep quality in patients with chronic lung disease was poor. In addition to expected improvements in symptoms, exercise tolerance, and HRQL after PR, the subgroup of patients with COPD had a significant improvement in sleep quality. These findings suggest that PR may be an effective, non-pharmacologic treatment option for sleep problems in patients with COPD.     

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.     

Health-related quality of life in COPD: why both disease-specific and generic measures should be used.

Although research has consistently demonstrated that chronic obstructive pulmonary disease (COPD) impairs health-related quality of life (HRQL), little agreement has been evidenced regarding the factors identified as contributing to impaired HRQL. The aim was to study such factors using well established generic and specific HRQL instruments. The patients (n=68) were stratified by forced expiratory volume in one second (FEV1) to represent a wide range of disease severity. Pulmonary function, blood gases and 6-min walking distance test (6MWD) were assessed. HRQL instruments included: St George's Respiratory Questionnaire (SGRQ), Sickness Impact Profile (SIP), Hospital Anxiety and Depression Scale and Mood Adjective Check List. The strength of the impact of COPD on HRQL was represented along a continuum ranging from lung function, functional status (physical and psychosocial) to wellbeing. Although correlations between FEV1 versus SGRQ total and SIP overall scores (r=-0.42 and -0.32) were stronger than previously reported, multiple regression analyses showed that lung function contributed little to the variance when dyspnoea-related limitation, depression scores and 6MWD were included in the models. These three factors were important to varying degrees along the whole range of HRQL. Physiological, functional and psychosocial consequences of chronic obstructive pulmonary disease are only poorly to moderately related to each other. The present study concludes that a comprehensive assessment of the effects of chronic obstructive pulmonary disease requires a battery of instruments that not only tap the disease-specific effects, but also the overall burden of the disease on everyday functioning and emotional wellbeing.     

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.     

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.     

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.     

Short-burst oxygen therapy for COPD patients: a 6-month randomised, controlled study.

Short-burst oxygen therapy (SBOT) remains widely advocated for patients with chronic obstructive pulmonary disease (COPD), despite a lack of supporting evidence. The aim of this randomised, double-blind, placebo-controlled, parallel group study was to determine whether SBOT improves health-related quality of life (HRQL) or reduces acute healthcare utilisation in patients discharged following an acute exacerbation of COPD. Consecutive patients were screened; 78 of 331 were eligible for randomisation to cylinder oxygen, cylinder air or usual care following discharge. Patients were elderly with high acute healthcare utilisation, forced expiratory volume in one second of <1 L and had dyspnoea limiting daily activity but were not hypoxaemic at rest. Over the 6-month study period, there were no significant differences between patient groups in HRQL (Chronic Respiratory Questionnaire (CRQ), 36-item Short-Form Health Survey, Hospital Anxiety and Depression Scale) except for CRQ emotion domain. There were no significant differences in acute healthcare utilisation. Time to readmission was greatest in the usual care group. Cylinder use was high initially, but rapidly fell to very low levels within weeks in both cylinder oxygen and air groups. In conclusion, the availability of short-burst oxygen therapy for chronic obstructive pulmonary disease patients discharged from hospital following an acute exacerbation did not improve health-related quality of life or reduce acute healthcare utilisation. These results provide no support for the widespread use of short-burst oxygen therapy.     

Resistance versus endurance training in patients with COPD and peripheral muscle weakness.

The effects of endurance training on exercise capacity and health-related quality of life (HRQL) in chronic obstructive pulmonary disease (COPD) patients have been studied thoroughly, while resistance training has been rarely evaluated. This study investigated the effects of resistance training in comparison with endurance training in patients with moderate to severe COPD and peripheral muscle weakness (isometric knee extension peak torque <75% predicted). Forty-eight patients (age 64+/-8 yrs, forced expiratory volume in one second 38+/-17% pred) were randomly assigned to resistance training (RT, n=24) or endurance training (ET, n=24). The former consisted of dynamic strengthening exercises. The latter consisted of walking, cycling and arm cranking. Respiratory and peripheral muscle force, exercise capacity, and HRQL were re-evaluated in all patients who completed the 12-week rehabilitation (RT n=14, ET n=16). Statistically significant increases in knee extension peak torque (RT 20+/-21%, ET 42+/-21%), maximal knee flexion force (RT 31+/-39%, ET 28+/-37%), elbow flexion force (RT 24+/-19%, ET 33+/-25%), 6-min walking distance (6MWD) (RT 79+/-74 m, ET 95+/-57 m), maximum workload (RT 15+/-16 Watt, ET 14+/-13 Watt) and HRQL (RT 16+/-25 points, ET 16+/-15 points) were observed. No significant differences in changes in HRQL and 6MWD were seen between the two treatments. Resistance training and endurance training have similar effects on peripheral muscle force, exercise capacity and health-related quality of life in chronic obstructive pulmonary disease patients with peripheral muscle weakness.     

The Italian multicentre study on noninvasive ventilation in chronic obstructive pulmonary disease patients.

Chronic obstructive pulmonary disease (COPD) patients with chronic ventilatory failure (CVF) are more likely to develop exacerbations, which are an important determinant of health-related quality of life (HRQL). Long-term noninvasive positive-pressure ventilation (NPPV) has been proposed in addition to long-term oxygen therapy (LTOT) to treat CVF but little information is available on its effects on HRQL and resource consumption. Therefore, the current authors undertook a 2-yr multicentric, prospective, randomised, controlled trial to assess the effect of NPPV+ LTOT on: 1) severity of hypercapnia; 2) use of healthcare resources, and 3) HRQL, in comparison with LTOT alone. One hundred and twenty-two stable hypercapnic COPD patients on LTOT for > or = 6 months were consecutively enrolled. After inclusion and 1-month run-in, 90 patients were randomly assigned to NPPV+LTOT (n=43) or to LTOT alone (n=47). Arterial blood gases, hospital and intensive care unit (ICU) admissions, total hospital and ICU length of stay and HRQL were primary outcome measures; survival and drop-out rates, symptoms (dyspnoea and sleep quality) and exercise tolerance were secondary outcome measures. Follow-up was performed at 3-month intervals up to 2 yrs. Lung function, inspiratory muscle function, exercise tolerance and sleep quality score did not change over time in either group. By contrast the carbon dioxide tension in arterial blood on usual oxygen, resting dyspnoea and HRQL, as assessed by the Maugeri Foundation Respiratory Failure Questionnaire, changed differently over time in the two groups in favour of NPPV+LTOT. Hospital admissions were not different between groups during the follow-up. Nevertheless, overall hospital admissions showed a different trend to change in the NPPV+LTOT (decreasing by 45%) as compared with the LTOT group (increasing by 27%) when comparing the follow-up with the follow-back periods. ICU stay decreased over time by 75% and 20% in the NPPV+LTOT and LTOT groups, respectively. Survival was similar. Compared with long-term oxygen therapy alone, the addition of noninvasive positive-pressure ventilation to long-term oxygen therapy in stable chronic obstructive pulmonary disease patients with chronic ventilatory failure: 1) slightly decreased the trend to carbon dioxide retention in patients receiving oxygen at home and 2) improved dyspnoea and health-related quality of life. The results of this study show some significant benefits with the use of nocturnal, home noninvasive positive-pressure ventilation in patients with chronic ventilatory failure due to advanced chronic obstructive pulmonary disease patients. Further work is required to evaluate the effect of noninvasive positive-pressure ventilation on reducing the frequency and severity of chronic obstructive pulmonary disease exacerbation.     

Pulmonary rehabilitation reduces depression and enhances health-related quality of life in COPD patients--especially in patients with mild or moderate disease

The first objective of the study was to evaluate a 4-week inpatient pulmonary rehabilitation program on exercise capacity, health-related quality of life (HRQL) and psychological distress in patients with COPD. The second objective was to investigate the influence of gender, age, disease severity, co-morbidity, anxiety and depression on improved HRQL after rehabilitation. The study comprised 136 consecutive patients from baseline to follow-up with mild-to-severe COPD. Exercise capacity was measured by the 6-min walking distance test, disease severity by spirometric tests, HRQL by The St. George's Respiratory Questionnaire and psychological distress by the The Hospital Anxiety and Depression Scale. Variables on socio-demography and co-morbidity were self-reported. Exercise capacity was improved from baseline to follow-up with a score difference of +44 metres (p = 000). Except for the activity score, HRQL was significantly improved: a change of -3.5 for the symptom score (p = 014), -3.1 for the total score (p = 003) and a clinical significant change of - 4.0 for the impact score (p = 002). The anxiety score did not change significantly after rehabilitation (-0.1, p = 545), though there was a significant reduction of the depression score (-0.8, p = 002) and a 10.4% reduction in the prevalence of possible depression cases (p = 017). Patients with forced expiratory volume in 1 second ≥50% predicted were 4.2 times more likely to achieve a clinical significant improved HRQL after rehabilitation than patients with forced expiratory volume in 1 second <50% predicted (95% confidence interval [CI] 1.7-10.3, p = 002). A 4-week inpatient rehabilitation program improves HRQL and exercise capacity and reduces depression in COPD patients. Patients with mild or moderate disease are more likely to achieve an improved HRQL after rehabilitation than patients with severe or very severe disease.     

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.     

慢性阻塞性肺疾病评估测试对生存质量的评估价值研究

目的探讨慢性阻塞性肺疾病(COPD)评估测试(CAT)用于我国COPD患者生存质量的应用价值。方法选择2010年4月至2011年2月中国医科大学附属第一医院呼吸内科就诊和定期随访的COPD患者107例,其中男57例,女50例,年龄40～86岁,平均(67.4±9.8)岁。分别对患者进行中文版CAT和圣.乔治呼吸问卷(SGRQ)调查,同时进行肺功能测定。验证CAT的信度及效度,采用Spearman秩相关分析CAT评分与SGRQ评分、CAT评分与肺功能指标之间的相关性。结果 CAT的克龙巴赫α系数为0.796;CAT每个问题单项分值与总分值的Spearman秩相关系数为0.413～0.758(P<0.01);通过因子分析,最终抽取2个维度,可以解释总体方差的59.18%,各维度与量表总体的相关系数(0.960,0.549,P<0.01)大于维度间的相关系数(0.292)(P<0.01)。CAT总评分与SGRQ总评分呈显著正相关(r=0.735,P<0.01),第一秒用力呼气容积占预计值百分比(FEV1%)呈显著负相关(r=-0.441,P<0.01),与FEV1占用力肺活量(FVC)百分比(FEV1/FVC)亦呈显著负相关(r=-0.324,P<0.01)。结论中文版CAT是一种简易、可靠、有效的新型COPD患者生存质量评估问卷,可以很好地反映中国COPD患者的生存质量,适用于中国COPD患者的生存质量的评估。     

Lack of additional effect of adjunct of assisted ventilation to pulmonary rehabilitation in mild COPD patients

Different modalities of assisted ventilation improve breathlessness and exercise tolerance in patients with chronic obstructive pulmonary disease (COPD).The aim of this study was to evaluate the effects of the addition of assisted ventilation during exercise training on the outcome of a structured pulmonary rehabilitation programme (PRP) in COPD patients. Thirty-three male patients with stable COPD (mean (SD) forced expiratory volume in 1 s (FEV1) 44 (16) % pred), without chronic ventilatory failure, undergoing a 6-week multidisciplinary outpatient PRP including exercise training, were randomised to training during either mask proportional assist ventilation (PAV: 18 patients) or spontaneous breathing (SB: 15 patients). Assessment included exercise tolerance, dyspnoea, leg fatigue, and health-related quality of life (HRQL). Five out of 18 patients (28%) in the PAV group dropped out due to lack of compliance with the equipment. Both groups showed significant post-PRP improvements in exercise tolerance (peak work rate difference: 20 (95% Cl 2.4-37.6) and 14 (3.8% CI to 24.2) W in PAV and SB group, respectively), dyspnoea and leg fatigue, but not in HRQL, without any significant difference between groups. It is concluded that with the modality and in the patients assessed in this study assisted ventilation during training sessions included in a multidisciplinary PRP was not well tolerated by all patients and gave no additional physiological benefit in comparison with exercise training alone.     

Natural history of emphysema

Chronic obstructive pulmonary disease (COPD) is a progressive disease with studies of disease progression generally focusing on measures of airflow and mortality. In nonsmokers, maximal lung function is attained around age 15 to 25 years, and after a variable plateau phase, subsequently declines at approximately 20 to 25 ml/year. Smoking may reduce the maximal FEV(1) achieved, shorten or eliminate the plateau phase, and may accelerate the rate of decline in lung function in a dose-dependent manner. Some smokers are predisposed to more rapid declines in lung function than others, and recent reports suggest that females may be at higher risk of lung damage related to smoke exposure than males. Progressive deterioration in dyspnea, functional status, and health-related quality of life (HRQL) in patients with COPD is well known, but the magnitude and rate of decline and its association with severity of airflow obstruction remains poorly defined. Many studies have identified pulmonary function, in particular the FEV(1), as the single best predictor of survival. An impaired diffusing capacity and overall impairment in functional status have also been associated with impaired survival in COPD. The National Emphysema Treatment Trial has provided additional insight into these features in a large, well-characterized group of patients with severe airflow obstruction and structural emphysema.     

Health-related quality of life in patients by COPD severity within primary care in Europe

Pan-European data on health-related quality of life (HRQL) in chronic obstructive pulmonary disease (COPD) are lacking. This cross-sectional epidemiological study evaluated health status in 1817 COPD patients from an 'all-comers' primary care population in seven European countries (87% stable disease; 13% with current exacerbation) using: St George's Respiratory Questionnaire-COPD specific (SGRQ-C), the short form health survey (SF-12) and the Functional Assessment of Chronic Illness Therapy (FACIT) Fatigue scale. Mean total score for SGRQ was 44.7?±?19.4 showing marked impairment of HRQL. Scores differed little between countries (range 39.2-50.1). Impairment was associated with the severity of airway obstruction, but within each GOLD stage the variation (SD) was wide [Stage I: 38.5?±?19.3 (n?=?223); Stage II: 40.4?±?18.1 (n?=?868); Stage III: 50.2?±?18.6 (n?=?551); Stage IV: 58.6?±?17.7 (n?=?144)]. Patients suffering an exacerbation had a worse SGRQ score (54.9?±?19.3) than those with stable disease (43.3?±?19.0). The presence of ≥3 co-morbidities (CM) was also associated with a significantly worse score (49.9?±?19.1) vs. 1-2 CM (42.1?±?19.1) or no CM (42.3?±?18.6). Findings with the SF-12 and FACIT-F results were consistent with those from the SGRQ-C. This large observational primary care study shows that health status is significantly impaired in COPD patients of all severities, even in those with mild airway obstruction. Within each GOLD stage of severity there is considerable heterogeneity in HRQL impairment among patients. (Study number: 111749).     

Content comparison of health-related quality of life instruments for COPD

BACKGROUND: Due to the increasing importance of quality of life assessments in chronic obstructive pulmonary disease (COPD) patients, and the increased use of the International Classification of Functioning, Disability and Health (ICF) for comparative purposes it is essential to understand the relationship between health-related quality of life (HRQL) instruments and the ICF. OBJECTIVE: The objective of this study was to compare the content of recommended COPD-specific HRQL instruments using the ICF as reference. COPD-specific instruments mentioned in widely accepted guidelines were linked to the ICF using standardized linking rules. The degree of agreement between various health professionals was assessed by calculating the kappa statistic. RESULTS: Eleven instruments were included. They varied strongly in the number of concepts contained and the number of ICF categories used to map these concepts. A total of 548 concepts were identified and linked to 60 different ICF categories. Only the single category 'dyspnea' was covered by all instruments, whilst 21 categories were unique to specific instruments. The relationships of the measures with the ICF were identified. CONCLUSIONS: This study may aid researchers and clinicians to choose the most appropriate instrument for a specific purpose as well as help compare studies that have used different instruments for HRQL assessment.     

Health-Related Quality of Life in Long Term Oxygen-Treated Chronic Obstructive Pulmonary Disease Patients

Chronic obstructive pulmonary disease (COPD) induces changes in daily activities and mood. Health-related quality of life (HRQL) measures are of particular relevance in the management of such patients, but predictors of HRQL have rarely been investigated. The aim of this study was to seek factors predicting HRQL in severe COPD patients under long term oxygen therapy (LTOT). The pulmonary function parameters at the start of LTOT were studied as potential predictors of future HRQL. HRQL was assessed after an average of 40 months follow-up by the Duke Health Profile (Duke) and by the St. George Respiratory Questionnaire (SGRQ). Sixty-one patients (47 males and 14 females) with a mean age of 66 years were included in the study. Stepwise multiple regression analyses conducted in each HRQL dimension identified few significantly predictive factors. By the Duke, higher Self-esteem scores were associated with higher Pao ₂ (p < 0.01) and with older age (p < 0.05); higher Social Health scores were associated with older age (p < 0.005), and higher Pain scores were associated with a higher FEV₁/FVC ratio (p < 0.05). By the SGRQ, the Activity score correlated with FEV₁/FVC (p < 0.05). The proportion of the variance in each score accounted for by covariates in the model did not exceed 10%. No other significant regression models could be identified using the other HRQL dimensions. Our findings demonstrated weak relations between lung function at the start of LTOT and some dimensions of HRQL measured by the Duke and the SGRQ at the end of follow-up. Accepted for publication: 9 July 1996     

Evaluation of health-related quality of life in low-income patients with COPD receiving long-term oxygen therapy

STUDY OBJECTIVE: To assess health-related quality of life (HRQL) in a low-income population of patients with hypoxemia and COPD receiving long-term oxygen therapy (LTOT). DESIGN: Cross-sectional study. SETTING: Large, tertiary care, university teaching hospital. Patients or participants: Thirty-six patients with COPD requiring LTOT (mean age, 63.5 years; mean FEV(1), 32.1% of predicted; PaO(2), 50.2 mm Hg) and 33 control subjects with COPD but no severe hypoxemia (mean age, 63.1 years; FEV(1), 35.7%; PaO(2), 66.5 mm Hg). INTERVENTIONS: Patients underwent pulmonary function testing to assess physiologic function and the degree of respiratory impairment. A baseline dyspnea index (BDI) was used to determine levels of dyspnea, and a 6-min walk test was performed to evaluate physical performance and exercise capacity. The St. George Respiratory Questionnaire (SGRQ) and the Medical Outcomes Study Short-Form 36-item questionnaire (SF-36) were used to assess health status and HRQL. Measurements and results: The scores on the SGRQ and SF-36 indicated severe impairment. Patients receiving LTOT showed a trend toward worse scores on most dimensions of the SGRQ and SF-36, but differences between groups were only statistically significant for the physical functioning and social functioning dimensions of the SF-36. Dyspnea, as measured by the BDI, significantly correlated with all questionnaire domains except the SF-36 pain index. CONCLUSIONS: The HRQL of these low-income patients with COPD was markedly impaired, with more pronounced impairment in those receiving LTOT. The severity of dyspnea was a significant predictor of various components of quality of life in these patients.     

Quality of life in patients with chronic alveolar hypoventilation.

Measurements of health-related quality of life (HRQL) have not been reported in patients with chronic alveolar hypoventilation (CAH) before starting home mechanical ventilation. The purpose of this study was to investigate quality of life in a population of such patients. Forty-four consecutive patients with CAH due to previous polio, scoliosis, healed pulmonary tuberculosis or neuromuscular disease answered a battery of condition specific and generic (Sickness Impact Profile, Hospital Anxiety and Depression scale, Mood Adjective Check List) self-report questionnaires. Spirometry, arterial blood gases and overnight oxygen saturation were measured. Patients with untreated CAH had significantly impaired HRQL compared to historical data from a healthy reference population. Sleep-related problems were frequent. Age, underlying disease, and standard bicarbonate correlated significantly with HRQL measures, albeit with modest levels of explained variance (8-37%). Patients with chronic alveolar hypoventilation due to neuromuscular or restrictive chest wall disorders had severely impaired health-related quality of life. Age, the underlying disease and severity of hypoventilation are each related to the health-related quality of life decrements. Health-related quality of life measurements add important information to traditional clinical observations.