Health-related Quality Of Life In Chronic Obstructive Pulmonary Disease Research Articles

Roles of the physical environment in health-related quality of life in patients with chronic obstructive pulmonary disease

RationaleMany clinical and psychological factors are known to influence the health-related quality of life (HRQL) in chronic obstructive pulmonary disease (COPD). However, research on whether environmental factors, such as air pollution, noise, temperature, and blue/green spaces also influence HRQL in COPD has not been systematically investigated. ObjectiveTo assess the relationship between air pollution, road traffic noise, temperature, and distance to blue/green spaces and respiratory-specific HRQL in COPD. MethodsWe used cross-sectional data from a multicenter study in 407 stable mild-to-very severe COPD patients from Barcelona (Catalonia). Patients answered the COPD Assessment Test (CAT) and Clinical COPD Questionnaire (CCQ). Individual residential exposure to air pollutants (nitrogen dioxide [NO2] and particulate matters of varying aerodynamic diameters [PM2.5, PM10, and PM2.5absorbance]), road traffic noise (Lden), and land surface temperature were estimated using long-term averages from land-use regression models, 24-h noise maps, and land surface temperature maps, respectively. We measured residential distances to blue/green spaces from the Urban Atlas. We used mixed-effect negative binomial (for CAT) and linear (for CCQ) regression models, adjusted for potential confounders, with a random effect by center. ResultsOf those patients, 85 % were male and had a mean (SD) age of 69 (9) years, CAT score of 12 (7), CCQ-total score of 1.4 (1.0), and post-bronchodilator forced expiratory volume in 1 s (FEV1) of 57 (18) %predicted. We found that NO2 and PM2.5absorbance were associated with worsened CAT and CCQ-mental scores, e.g., 0.15-unit change in CAT score [regression coefficient (β) = 0.15; 95 % confidence interval (CI) = 0.03, 0.26] per interquartile range in NO2 [13.7 μg/m3]. Greater distances to blue/green spaces were associated with worsened CCQ-mental scores [0.08; 0.002, 0.15]. ConclusionsOur study showed that increased air pollution, particularly NO2 and PM2.5absorbance and greater distances to blue/green spaces negatively influence HRQL in COPD patients. These findings have important implications for the WHO promotion to develop healthy cities for our future.

The relationship between body mass index and health-related quality of life in COPD: real-world evidence based on claims and survey data

BackgroundBody mass index (BMI) is an important parameter associated with mortality and health-related quality of life (HRQoL) in chronic obstructive pulmonary disease (COPD). However, informed guidance on stratified weight recommendations for COPD is still lacking. This study aims to determine the association between BMI and HRQoL across different severity grades of COPD to support patient management.MethodsWe use conjunct analysis of claims and survey data based on a German COPD disease management program from 2016 to 2017. The EQ-5D-5L visual analog scale (VAS) and COPD Assessment Test (CAT) are used to measure generic and disease-specific HRQoL. Generalized additive models with smooth functions are implemented to evaluate the relationship between BMI and HRQoL, stratified by COPD severity.Results11,577 patients were included in this study. Mean age was 69.4 years and 59% of patients were male. In GOLD grades 1–3, patients with BMI of around 25 had the best generic and disease-specific HRQoL, whereas in GOLD grade 4, obese patients had the best HRQoL using both instruments when controlled for several variables including smoking status, income, COPD severity, comorbidities, emphysema, corticosteroid use, and days spent in hospital.ConclusionThis real-world analysis shows the non-linear relationship between BMI and HRQoL in COPD. HRQoL of obese patients with mild to severe COPD might improve following weight reduction. For very severe COPD, a negative association of obesity and HRQoL could not be confirmed. The results hint at the need to stratify COPD patients by disease stage for optimal BMI management.

Impact of Clinical Factors on Generic and Disease-Specific Quality of Life in COPD and Asthma-COPD Overlap with Exacerbations.

Purpose The health-related quality of life (HRQL) in chronic obstructive pulmonary disease (COPD) is worsened by frequent exacerbations, and it can be affected by the concomitant presence of bronchial asthma (asthma-COPD overlap (ACO)). The impacts of clinical factors associated with HRQL have not been compared in patients with COPD and ACO experiencing exacerbations. Patients and Methods. Patients with COPD (N =705) and ACO (N =148) belonging to C and D groups according to GOLD 2017 were recruited in stable condition. Demographic and clinical data were collected, spirometry was performed, and patients rated the intensity of respiratory symptoms during the previous week. The COPD Assessment Test (CAT) and the EQ-5D 3 level version (dimensions and visual analogue scale (VAS)) were used to assess disease-specific and generic HRQL, respectively. Fisher's exact test, χ2 test, ANOVA, and Pearson correlation were used for analysis (mean ± SD). Multiple linear regression was applied to identify variables related to CAT and EQ-5D VAS scores. Results The CAT and EQ-5D VAS scores showed similarly low HRQL in COPD and ACO (20.7 ± 6.7 vs. 21.1 ± 6.3 (p = 0.52) and 56.2 ± 17.8 vs. 53.7 ± 18.2 (p = 0.11)). There was a weak correlation between CAT and EQ-5D VAS scores (COPD: r = −0.345, p < 0.001; ACO: r = −0.245, p = 0.003). More patients with COPD had problems related to anxiety/depression in EQ-5D (63.7% vs. 55.4%, p = 0.06). Pack-years exerted a negative effect on HRQL measures both in ACO and COPD. Low HRQL in COPD was associated with female gender, dyspnea, cough, gastroesophageal reflux disease, and arrhythmia, while in ACO, it was related to arrhythmia, hypertension, and cough, but less to dyspnea. Conclusions Patients with COPD and ACO experiencing exacerbations have low quality of life, which is influenced by smoking history, symptoms, and comorbidities. These findings have important implications for the development of therapeutic strategies to improve the health status of patients with these conditions.

Quantifying heterogeneity of physical and mental health-related quality of life in chronic obstructive pulmonary disease patients in the United States

ABSTRACT Background Chronic obstructive pulmonary disease (COPD) is a heterogenous condition. This study aims to quantify the heterogeneity of Health-related Quality of Life (HRQoL), and identify subgroups with the lowest HRQoL, in COPD patients in the United States (US). Methods Data from 2008–2015 Medical Expenditure Panel Survey were used to examine the heterogeneity of HRQoL between different COPD subgroups using mixed-effects modeling and G-computation. The Physical Composite Summary (PCS) and Mental Composite Summary (MCS) scores from the Short-Form-12 questionnaire were utilized. We also compared the heterogeneity of HRQoL in our COPD cohort against that in a matched non-COPD cohort. Results The final sample consisted of 1,866 (weighted = 19,952,143) COPD patients with a mean age of 63.2 years (Standard error (SE):0.38), mean MCS score of 46.84 (SE:0.35), and mean PCS score of 35.65 (SE:0.32). The adjusted MCS and PCS scores ranged from 36.19 to 53.06, and from 25.52 to 48.27, respectively, for COPD subgroups. COPD patients had statistically significantly lower MCS and PCS scores by 4.61, and 5.86 points, respectively, compared to the matched non-COPD cohort, and MCS scores showed a wider variability in the COPD cohort. Conclusion Our study quantifies substantial heterogeneity of HRQoL in COPD in the US and provides evidence for prioritizing COPD subgroups with the lowest HRQoL for targeted interventions.

PRS60 IMPACT OF SLEEP DISTURBANCE ON HEALTH-RELATED QUALITY OF LIFE IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD): WHAT DO WE KNOW SO FAR?

Extrapulmonary impacts of chronic obstructive pulmonary disease (COPD) often include sleep disturbance, poor sleep quality, and daytime sleepiness resulting in detrimental impact on patients' overall health-related quality of life (HRQoL). This study evaluated the impact of sleep disturbance on HRQoL in patients with COPD. Literature searches were performed in biomedical databases until March 2019. Specific search terms identified observational studies assessing HRQoL in COPD that included sleep as a patient-reported outcome (PRO) endpoint. Only full text articles published in English were included. Out of total 1247 abstracts identified for initial screening, 177 were selected for full text review. Based on the inclusion criteria, PRO-related information from 36 studies are analyzed. Sleep disturbances and poor sleep quality was on average prevalent in more than one-third, ranging from 27%-100% of COPD patients. Sleep measures such as the Pittsburgh Sleep Quality Index (PSQI), PROMIS-sleep disturbance domain, Epworth Sleepiness Scale (ESS), Insomnia Severity Index (ISI), and COPD and Asthma Sleep Impact Scale (CASIS) showed significant correlations (all p<0.05) with HRQoL [determined by COPD Assessment Test (CAT), 36-Item Short Form Health Survey (SF-36), the Nottingham Health Profile (NHP) and the St George's Respiratory Questionnaire (SGRQ)]. Univariate and multivariate analyses showed that sleep quality (evaluated by PSQI) is an important determinant for HRQoL in COPD. Furthermore, HRQoL is an important predictor of sleep quality, thereby establishing bidirectional relationship. “Good sleepers” (PSQI<5) have better HRQoL compared to “poor sleepers” (PSQI≥5). Increased sleep disturbance is associated with emotional impact. Both significant (all p<0.05) and non-significant (all p>0.05) results were seen for associations of sleep with disease severity. Overall, there is a bidirectional relationship of sleep quality and HRQoL in COPD. Sleep quality is an independent significant predictor of HRQoL in COPD. Hence, sleep should be considered an important HRQoL component when evaluating the health status of COPD patients.

Investigating the association between medication adherence and health-related quality of life in COPD: Methodological challenges when using a proxy measure of adherence

BackgroundThe association between non-adherence to medication and health-related quality-of-life (HRQoL) in Chronic Obstructive Pulmonary Disease (COPD) remains poorly understood. Different ways to deal with methodological challenges to estimate this association have probably contributed to conflicting results. AimTo investigate the association between medication adherence and HRQoL, thereby illustrating methodological challenges that need to be addressed. MethodsWe used longitudinal patient-level data from a cluster-randomized controlled trial (i.e. RECODE) including three-year data on type and dose of COPD maintenance medication prescribed and HRQoL (Clinical COPD Questionnaire [CCQ], st. George Respiratory Questionnaire [SGRQ], EuroQol 5-dimensions [EQ-5D]) of 511 patients. A linear mixed model was used to assess the association between adherence and HRQoL using a fixed cut-off of 80% of the proportion of days covered (PDC) to define adherence. Subsequently, we investigated the impact of differences in disease severity; lifestyle; and reversed causality, representing the methodological challenges. Additionally, we investigated the impact of changing the definition of adherence. ResultsIn unadjusted analyses, and analyses adjusting for demographic characteristics only, SGRQ score was worse in the adherent compared to the non-adherent group. This association disappeared when correcting for disease severity and/or lifestyle. A better SGRQ score was predictive of decreased adherence in the following year. However, accounting for the previous HRQoL did not result in positive associations between adherence and HRQoL. When defining four categories of adherence, patients with a PDC between 80 and 99% had a significantly worse SGRQ score compared to patients with a PDC <60%, even after correction for lifestyle. There was no significant association between adherence and CCQ or EQ-5D. ConclusionThis study showed persistent methodological challenges in the investigation of the effect of medication adherence on HRQoL in COPD. A positive association of adherence and HRQoL was not found, even after adjusting for lifestyle, disease severity, and previous HRQoL.

Comorbid Influences on Generic Health-Related Quality of Life in COPD: A Systematic Review.

BackgroundChronic obstructive pulmonary disease (COPD) is a leading cause of mortality and of loss of disability-adjusted life years worldwide. It often is accompanied by the presence of comorbidity.ObjectivesTo systematically review the influence of COPD comorbidity on generic health-related quality of life (HRQoL).MethodsA systematic review approach was used to search the databases Pubmed, Embase and Cochrane Library for studies evaluating the influence of comorbidity on HRQoL in COPD. Identified studies were analyzed according to study characteristics, generic HRQoL measurement instrument, COPD severity and comorbid HRQoL impact. Studies using only non-generic instruments were excluded.Results25 studies met the selection criteria. Seven studies utilized the EQ-5D, six studies each used the SF-36 or SF-12. The remaining studies used one of six other instruments each. Utilities were calculated by four EQ-5D studies and one 15D study. Patient populations covered both early and advanced stages of COPD and ranged from populations with mostly stage 1 and 2 to studies with patients classified mainly stage 3 and 4. Evidence was mainly created for cardiovascular disease, depression and anxiety as well as diabetes but also for quantitative comorbid associations. Strong evidence is pointing towards the significant negative association of depression and anxiety on reduced HRQoL in COPD patients. While all studies found the occurrence of specific comorbidities to decrease HRQoL in COPD patients, the orders of magnitude diverged. Due to different patient populations, different measurement tools and different concomitant diseases the study heterogeneity was high.ConclusionsFacilitating multimorbid intervention guidance, instead of applying a parsimony based single disease paradigm, should constitute an important goal for improving HRQoL of COPD patients in research and in clinical practice.

Depression and heart failure associated with clinical COPD questionnaire outcome in primary care COPD patients: a cross-sectional study.

Background:Improvement in health-related quality of life (HRQoL) is one of the main goals in treating chronic obstructive pulmonary disease (COPD). Impaired HRQoL in COPD is associated with increased morbidity and mortality, hospitalisations and burden on our health-care system. The Clinical COPD Questionnaire (CCQ) is a validated, reliable, short questionnaire for the evaluation of disease-specific HRQoL in patients with COPD in primary care.Aims:To investigate factors that might be associated with CCQ outcome in COPD in a primary care setting.Methods:In a population of COPD patients in primary care, multiple regression analyses were used to assess associations between CCQ outcome and depression, heart failure, FEV1% predicted, FEV1/FVC, age, sex, body mass index and current smoking.Results:Data from 341 patients (mean age 68.1±10.3, COPD GOLD class I–III) were used for analyses. Together, heart failure and depression explained 23% of the variance in CCQ total score (P<0.001, N=93). Heart failure was most strongly associated with CCQ functional score (27% explained variance, P<0.001, N=100), whereas depression was most strongly associated with CCQ mental score (22% explained variance, P<0.001, N=93).Conclusions:CCQ outcomes are higher in COPD patients with heart failure and depression. These findings might imply that heart failure and depression affect HRQoL of patients with COPD, and thus emphasise the importance of a holistic approach of this complex disease, leading to a correct diagnosis of COPD and its comorbidities, to achieve better tailored treatment of chronic patients.

Identifying key domains of health-related quality of life for patients with chronic obstructive pulmonary disease: the patient perspective.

BackgroundNumerous instruments are available to measure health-related quality of life (HRQoL) in patients with Chronic Obstructive Pulmonary Disease (COPD), covering a wide array of domains ranging from symptoms such as dyspnea, cough and wheezing, to social and emotional functioning. Currently no information or guide is available yet to aid the selection of domains for a particular study or disease population. The aim of this paper is to identify which domains of HRQoL are most important with respect to COPD, from the patient perspective.MethodsTwenty-one Dutch patients with COPD were asked to describe important domains impacted by COPD freely; second, they were presented with cues (domains from the Patient-Reported Outcomes Measurement Information System (PROMIS) framework) and were asked to select the domains that were most relevant to them. During the interview, the patients were asked to indicate in which way the selected domains impact their lives. Both the answers to the open question, and the patient statements motivating nomination of PROMIS domains were coded into themes.ResultsThe most relevant (sub)domains of HRQoL for patients with COPD were: physical health (fatigue, physical functioning), social health (instrumental support, ability to participate in social roles and activities, companionship, and emotional support), and coping with COPD.ConclusionWe identified which domains of HRQoL are most important to patients with COPD. One of these (coping with COPD) is not explicitly covered by PROMIS, or by traditional questionnaires that are used to measure HRQoL in COPD.

Co-morbidities are the key nominators of the health related quality of life in mild and moderate COPD.

BackgroundCo-morbidities are common in chronic obstructive pulmonary disease (COPD). We assessed the contribution of common co-morbidities on health related quality of life (HRQoL) among COPD patients.MethodsUsing both generic (15D) and respiratory-specific (AQ20) instruments, HRQoL was assessed in a hospital based COPD population (N = 739, 64% males, mean age 64 years, SD 7 years) in this observational study with inferential analysis. The prevalence of their co-morbidities was compared with those of 5000 population controls. The patients represented all severity stages of COPD and the patterns of common concomitant disorders differed between patients.ResultsCo-morbidities such as psychiatric conditions, alcohol abuse, cardiovascular diseases, and diabetes were more common among COPD patients than in age and gender matched controls. Psychiatric conditions and alcohol abuse were the strongest determinants of HRQoL in COPD and could be detected by both 15D (Odds Ratio 4.7 and 2.3 respectively) and AQ20 (OR 2.0 and 3.0) instruments. Compared to respiratory specific AQ20, generic 15D was more sensitive to the effects of comorbidities while AQ20 was slightly more sensitive for the low FEV1. FEV1 was a strong determinant of HRQoL only at more severe stages of disease (FEV1 < 40% of predicted). Poor HRQoL also predicted death during the next five years.ConclusionsThe results suggest that co-morbidities may impair HRQoL at an early stage of the disease, while bronchial obstruction becomes a significant determinant of HRQoL only in severe COPD.

Depression and anxiety predict health-related quality of life in chronic obstructive pulmonary disease: systematic review and meta-analysis.

BackgroundThe causal association between depression, anxiety, and health-related quality of life (HRQoL) in chronic obstructive pulmonary disease (COPD) is unclear. We therefore conducted a systematic review of prospective cohort studies that measured depression, anxiety, and HRQoL in COPD.MethodsElectronic databases (Medline, Embase, Cumulative Index to Nursing and Allied Health Literature [CINAHL], British Nursing Index and Archive, PsycINFO and Cochrane database) were searched from inception to June 18, 2013. Studies were eligible for inclusion if they: used a nonexperimental prospective cohort design; included patients with a diagnosis of COPD confirmed by spirometry; and used validated measures of depression, anxiety, and HRQoL. Data were extracted and pooled using random effects models.ResultsSix studies were included in the systematic review; of these, three were included in the meta-analysis for depression and two were included for the meta-analysis for anxiety. Depression was significantly correlated with HRQoL at 1-year follow-up (pooled r=0.48, 95% confidence interval 0.37–0.57, P<0.001). Anxiety was also significantly correlated with HRQoL at 1-year follow-up (pooled r=0.36, 95% confidence interval 0.23–0.48, P<0.001).ConclusionAnxiety and depression predict HRQoL in COPD. However, this longitudinal analysis does not show cause and effect relationships between depression and anxiety and future HRQoL. Future studies should identify psychological predictors of poor HRQoL in well designed prospective cohorts with a view to isolating the mediating role played by anxiety disorder and depression.

Health-related quality of life in chronic obstructive pulmonary disease patients in Korea.

BackgroundThere are few publications on quality measurement of COPD health state according to the severity level using EQ-5D in Korea. The present study aimed to evaluate the health-related quality of life (HRQoL) in patients with chronic obstructive pulmonary disease (COPD) in terms of disease severity in Korea.MethodsTotally two hundred patients with COPD were consecutively recruited in one tertiary hospital of Korea. Each respondent was asked to fill out the questionnaire through a face-to-face interview after providing informed consent. The questionnaire included general and clinical characteristics as well as the EQ-5D and Clinical COPD Questionnaire (CCQ). HRQoL was evaluated according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria and severity of breathlessness.ResultsThe adjusted mean EQ-5D index scores were 0.83, 0.88, 0.81 and 0.60 in stage I, II, III and IV, respectively. The EQ-5D index tended to decrease with GOLD criteria. The adjusted mean EQ-Visual Analog Scale (VAS) scores ranged from 65.1 in stage IV to 73.9 in stage I. The CCQ total scores deteriorated with an increasing GOLD stage and severity of breathlessness (all P < 0.001). The correlation between CCQ total score and EQ-5D index was −0.69.ConclusionsOur study shows that HRQoL in COPD measured by EQ-5D and CCQ worsens with the GOLD stage and severity of breathlessness. EQ-5D and CCQ could be useful instruments for an evaluation of HRQoL in COPD patients in Korea.

Bayesian predictors of very poor health related quality of life and mortality in patients with COPD

BackgroundChronic obstructive pulmonary disease (COPD) is associated with increased mortality and poor health-related quality of life (HRQoL) compared with the general population. The objective of this study was to identify clinical characteristics which predict mortality and very poor HRQoL among the COPD population and to develop a Bayesian prediction model.MethodsThe data consisted of 738 patients with COPD who had visited the Pulmonary Clinic of the Helsinki and Turku University Hospitals during 1995–2006. The data set contained 49 potential predictor variables and two outcome variables: survival (dead/alive) and HRQoL measured with a 15D instrument (very poor HRQoL < 0.70 vs. typical HRQoL ≥ 0.70).In the first phase of model validation we randomly divided the material into a training set (n = 538), and a test set (n = 200). This procedure was repeated ten times in random fashion to obtain independently created training sets and corresponding test sets. Modeling was performed by using the training set, and each model was tested by using the corresponding test set, repeated in each training set. In the second phase the final model was created by using the total material and eighteen most predictive variables. The performance of six logistic regressions approaches were shown for comparison purposes.ResultsIn the final model, the following variables were associated with mortality or very poor HRQoL: age at onset, cerebrovascular disease, diabetes, alcohol abuse, cancer, psychiatric disease, body mass index, Forced Expiratory Volume (FEV1) % of predicted, atrial fibrillation, and prolonged QT time in ECG. The prediction accuracy of the model was 77%, sensitivity 0.30, specificity 0.95, positive predictive value 0.68, negative predictive value 0.78, and area under the ROC curve 0.69. While the sensitivity of the model reminded limited, good specificity, moderate accuracy, comparable or better performance in classification and better performance in variable selection and data usage in comparison to the logistic regression approaches, and positive and negative predictive values indicate that the model has potential in predicting mortality and very poor HRQoL in COPD patients.ConclusionWe developed a Bayesian prediction model which is potentially useful in predicting mortality and very poor HRQoL in patients with COPD.

Improving the quality of life in patients with chronic obstructive pulmonary disease: focus on indacaterol

Chronic obstructive pulmonary disease (COPD) is a common disease in the general population and it places a considerable burden on patients, with the disease negatively affecting quality of life. In practice, patients with COPD generally seek medical attention because of symptoms, particularly breathlessness, and the resulting physical limitations, which affect the health-related quality of life (HR-QOL) in patients. The defining feature of COPD is airflow limitation that causes air trapping and increased hyperinflation as the ventilation rate increases during physical effort. Hyperinflation causes or worsens breathlessness as breathing becomes inefficient, with the end result being an avoidance of physical exertion and a cycle of increasing dyspnea caused by inactivity and deconditioning, with deleterious effects on HR-QOL. Current published guidelines for COPD state that the goals of pharmacologic therapy should be to control symptoms, improve health status and exercise tolerance, and reduce the frequency of COPD exacerbations. Effective and sustained bronchodilation has emerged as a key strategy for improving dyspnea and ability to exercise. As there is no cure for COPD, a major goal of treatment and of research into new therapies is to improve HR-QOL in COPD patients.ConclusionMore recently, indacaterol, an inhaled ultra-long-acting β2-agonist (24-hour action), has been approved in many countries at different doses (between 75 and 300 μg once daily) for treatment of patients with stable but symptomatic COPD. The aim of this review was to explore once-daily indacaterol clinical data as related to improvement in HR-QOL in COPD. Indacaterol studies have shown significant improvements in lung function of COPD patients, and these improvements have also translated into clinically meaningful improvements in patient symptoms and HR-QOL.

Pain in people with chronic obstructive pulmonary disease (COPD)

The prevalence and characteristics of pain are not known in COPD patients. The purposes of this study were to determine if pain is more common in COPD patients than in healthy people and if it was related to self-reported physical activity, health related quality of life (HRQoL) and comorbidities. Participants returned a mailed survey package that contained: 1) McGill Pain Questionnaire (MPQ) and Brief Pain Inventory (BPI) to evaluate pain severity and how pain interferes with activities; 2) Tampa Scale for Kinesiophobia (TSK) to evaluate fear of movement related to pain; 3) Short Form-36 (SF-36), to measure HRQoL; 4) Community Health Activities Model Program for Seniors (CHAMPS) to evaluate physical activity; 5) a form to list medications and comorbidities. Forty-seven COPD patients and 47 age- and gender-matched healthy people responded. People with COPD demonstrated more pain (MPQ and BPI, p=0.000), a greater pain-related interference in their lives (BPI, p=0.000), a higher pain-related fear of movement, and lower frequency and energy expenditure of physical activities (CHAMPS, p=0.000) than healthy people (TSK, p<0.001). Pain severity (MPQ and BPI) was indirectly correlated to the Physical Component Score of the SF-36. COPD patients identified pain in the neck and trunk 3.1 times more often than healthy people. The number of comorbidities was the most consistent independent correlate of pain in COPD patients. COPD patients demonstrate more pain which interferes with activities more so than healthy people of similar age. Pain is also negatively associated with HRQoL in COPD.

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.