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

[Risk factors for mortality in chronic obstructive pulmonary disease]

OBJECTIVE

Although the factors predictive of survival in patients with chronic obstructive pulmonary disease (COPD) have been widely studied, full consensus has yet to be reached. The objective of this study was to further clarify how lung function parameters, exercise tolerance, and quality of life influence survival in patients with COPD.

PATIENTS AND METHODS

This prospective study included 60 patients diagnosed with COPD. At the start of the study, patients underwent respiratory function tests, exercise testing, and 6-minute walk test. They also answered a chronic respiratory disease questionnaire to measure health-related quality of life. Follow-up lasted 7 years.

RESULTS

Five of the 60 patients withdrew from the study. Twenty-six of the remaining 55 patients (47%) died during the study. Univariate Cox regression analysis showed a correlation between survival and age, degree of obstruction, inspiratory capacity, carbon monoxide diffusing capacity, and peak exercise tolerance. No correlation was found between survival and body mass index, PaO2, PaCO2, total lung capacity, residual volume, maximal respiratory pressures, 6-minute walk distance, or health-related quality of life. Age, degree of obstruction (measured as the ratio of forced expiratory volume in 1 second to forced vital capacity after administration of bronchodilator), and maximum minute ventilation in the exercise test were introduced initially in the multivariate Cox stepwise regression analysis, but only maximum minute ventilation remained in the final model (relative risk, 0.926; P< .001).

CONCLUSIONS

Our findings show that peak exercise tolerance is the best predictor of survival in patients with COPD.

Chronic obstructive pulmonary disease: a chronic systemic inflammatory disease

Chronic obstructive pulmonary disease (COPD) is characterized by chronic inflammation in both the airways causing airway obstruction and the lung tissues causing emphysema. The disease is induced by inhalation of noxious gasses and particulate matter resulting in a chronic persistent inflammatory response in the lung, and the extent of the inflammatory reaction correlates with the severity of the disease. This chronic inflammatory response in the lung is also associated with a significant systemic inflammatory response with downstream adverse clinical health effects. The systemic response in COPD is associated with mortality, specifically cardiovascular mortality. This review describes the nature of the systemic inflammatory response in COPD and the clinical manifestations associated with the systemic response, with a focus on the potential mechanisms for these adverse health effects.

The SAFE (SGRQ score, air-flow limitation and exercise tolerance) Index: a new composite score for the stratification of severity in chronic obstructive pulmonary disease

BACKGROUND

This study was proposed to develop a composite of outcome measures using forced expiratory volume percentage of predicted, exercise capacity and quality of life scores for assessment of chronic obstructive pulmonary disease (COPD) severity.

MATERIALS AND METHODS

Eighty-six patients with COPD were enrolled into a prospective, observational study at the respiratory outpatient clinic, National University Hospital Malaysia (Hospital Universiti Kebangsaan Malaysia--HUKM), Kuala Lumpur.

RESULTS

Our study found modest correlation between the forced expiratory volume in 1 s (FEV(1)), 6 min walk distance and the SGRQ scores with mean (SD) values of 0.97 (0.56) litres/s, 322 (87) m and 43.7 (23.6)%, respectively. K-Means cluster analysis identified four distinct clusters which reached statistical significance which was refined to develop a new cumulative staging system. The SAFE Index score correlated with the number of exacerbations in 2 years (r = 0.497, p<0.001).

CONCLUSION

We have developed the SGRQ, Air-Flow limitation and Exercise tolerance Index (SAFE Index) for the stratification of severity in COPD. This index incorporates the SGRQ score, the FEV(1) % predicted and the 6 min walk distance. The SAFE Index is moderately correlated with the number of disease exacerbations.

Using the St. George Respiratory Questionnaire To Ascertain Health Quality in Persons With Treated Pulmonary Tuberculosis

INTRODUCTION

Pulmonary tuberculosis (PTB) can result in anatomic and functional changes that are associated with pulmonary impairment after tuberculosis that occurs frequently and varies in severity. We completed the St. George Respiratory Questionnaire (SGRQ), a health-related quality-of-life (HRQoL) instrument validated for several types of lung disease, for patients in whom PTB or latent tuberculosis infection (LTBI) has been diagnosed. We measured HRQoL pattern changes and the usefulness of the SGRQ in their ascertainment.

METHODS

Participants with known pulmonary function and a history of PTB or LTBI completed HRQoL questionnaires. The SGRQ was validated for content and construct using pulmonary function tests and the Medical Outcomes Study questionnaire. Internal consistency and test-retest methods assessed reliability. Significance of findings was determined with one-way analysis of variance with between-group comparisons.

RESULTS

Over 15 months, 313 subjects completed the SGRQ. The SGRQ was valid and reliable in the study population (intraclass correlation, 0.927; p<0.01; Cronbach alpha, 0.93). The mean total score for posttuberculosis patients was significantly higher than for that for LTBI score (23.5 [SE, 2.2] vs 10.3 [SE, 1.0], respectively; p<0.001).

CONCLUSIONS

We validated the SGRQ in a diverse population microbiologically cured of tuberculosis and found a mean 13.5-U difference in SGRQ score between these patients and a comparison group with similar risk factors (p<0.001). This difference indicates impairment after PTB has a substantial impact on human health worldwide. The microbiological cure of tuberculosis is not sufficient to avert chronic health loss. More aggressive treatment of LTBI and other case-preventing strategies is warranted worldwide.

Characterisation of phenotypes based on severity of emphysema in chronic obstructive pulmonary disease

BACKGROUND

Airflow limitation in chronic obstructive pulmonary disease (COPD) is caused by a mixture of small airway disease and emphysema, the relative contributions of which may vary among patients. Phenotypes of COPD classified purely based on severity of emphysema are not well defined and may be different from the classic phenotypes of "pink puffers" and "blue bloaters".

METHODS

To characterise clinical phenotypes based on severity of emphysema, 274 subjects with COPD were recruited, excluding those with physician-diagnosed bronchial asthma. For all subjects a detailed interview of disease history and symptoms, quality of life (QOL) measurement, blood sampling, pulmonary function tests before and after inhalation of salbutamol (0.4 mg) and high-resolution CT scanning were performed.

RESULTS

Severity of emphysema visually evaluated varied widely even among subjects with the same stage of disease. No significant differences were noted among three groups of subjects classified by severity of emphysema in age, smoking history, chronic bronchitis symptoms, blood eosinophil count, serum IgE level or bronchodilator response. However, subjects with severe emphysema had significantly lower body mass index (BMI) and poorer QOL scores, evaluated using St George's Respiratory Questionnaire (SGRQ), than those with no/mild emphysema (mean (SD) BMI 21.2 (0.5) vs 23.5 (0.3) kg/m(2), respectively; SGRQ total score 40 (3) vs 28 (2), respectively; p<0.001 for both). These characteristics held true even if subjects with the same degree of airflow limitation were chosen.

CONCLUSIONS

The severity of emphysema varies widely even in patients with the same stage of COPD, and chronic bronchitis symptoms are equally distributed irrespective of emphysema severity. Patients with the phenotype in which emphysema predominates have lower BMI and poorer health-related QOL.

Costs of chronic obstructive pulmonary disease (COPD) in Italy: the SIRIO study (social impact of respiratory integrated outcomes)

Chronic respiratory diseases affect a large number of subjects in Italy and are characterized by high socio-health costs. The aim of the Social Impact of Respiratory Integrated Outcomes (SIRIO) study was to measure the health resources consumption and costs generated in 1 year by a population of patients with chronic obstructive pulmonary disease (COPD) in a real-life setting. This bottom-up, observational, prospective, multicentric study was based on the collection of demographic, clinical, diagnostic, therapeutic and outcome data from COPD patients who reported spontaneously to pneumological centers participating in the study, the corresponding economic outcomes being assessed at baseline and after a 1-year survey. A total of 748 COPD patients were enrolled, of whom 561 [408 m, mean age 70.3 years (SD 9.2)] were defined as eligible by the Steering Committee. At the baseline visit, the severity of COPD (graded according to GOLD 2001 guidelines) was 24.2% mild COPD, 53.7% moderate and 16.8% severe. In the 12 months prior to enrollment, 63.8% visited a general practitioner (GP); 76.8% also consulted a national health service (NHS) specialist; 22.3% utilized Emergency Care and 33% were admitted to hospital, with a total of 5703 work days lost. At the end of the 1-year survey, the severity of COPD changed as follows: 27.5% mild COPD, 47.4% moderate and 19.4% severe. Requirement of health services dropped significantly: 57.4% visited the GP; 58.3% consulted an NHS specialist; 12.5% used Emergency Care and 18.4% were hospitalized. Compared to baseline, the mean total cost per patient decreased by 21.7% (p<0.002). In conclusion, a significant reduction in the use of health resources and thus of COPD-related costs (both direct and indirect costs) was observed during the study, likely due to a more appropriate care and management of COPD patients.

Predictors of Mortality in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) has become a major and growing health problem, with a mortality rate that continues to increase. Several factors, have been identified as individual predictors of mortality in COPD. This article reviews individual predictors for mortality. It also discusses the ability of an integrated, multidimensional tool to more broadly characterize COPD severity, assess response to therapeutic interventions and exacerbations, and predict mortality.

Advanced chronic obstructive pulmonary disease: innovative approaches to palliation

By the year 2020, chronic obstructive pulmonary disease (COPD) will be the third leading cause of death globally. While there have been consistent calls for increased palliative care involvement in the care of patients with advanced COPD, these calls should be based on empirical evidence that such an approach improves the symptom burden and poor quality of life associated with advanced COPD. Rather than reviewing the traditional treatments of airflow obstruction and palliative measures familiar to the palliative care community, we will focus on some novel approaches to the management of patients with advanced COPD from the perspective of clinicians involved in end of life care provision and research. By combining the clinical and research skills of pulmonologists and palliative medicine specialists we can advance the care of patients with this progressive and incurable disease.

Physiologic variables and functional status independently predict COPD hospitalizations and emergency department visits in patients with severe COPD

Using clinical and claims records from the National Emphysema Treatment Trial, we sought to identify factors that accurately predicted COPD exacerbations. This prospective cohort study consisted of subjects with severe emphysema randomized to medical therapy. Exacerbations were defined as a hospitalization or emergency department visit for COPD. Patient characteristics obtained before randomization were entered as independent variables in multivariable logistic regression models to estimate the risk of exacerbation. Discrimination was determined using the area under the receiver operator characteristic curve (AUC). Baseline measures included demographics, body mass index, pulmonary function, arterial blood gases, radiology studies, dyspnea (Shortness of Breath Questionnaire - SOBQ), health-related quality of life (St. George's Respiratory Questionnaire - SGRQ), 6-minute walk, exercise capacity, medication use, prior exacerbations and co-morbidity. In 610 participants, 26.6% had a COPD exacerbation over 1-year follow-up. In a model incorporating spirometry, PaO2, dyspnea, prior exacerbations and co-morbidity, a 5-point decrement in percent predicted FEV1 (OR 1.16, 95% CI 1.00-1.34) and a 5-point worsening in SOBQ (OR 1.08, 1.02-1.14) independently predicted exacerbations (AUC for full model 0.68). Combining physiologic variables, dyspnea, prior exacerbations and co-morbidity may be useful in identifying patients at high risk for COPD exacerbations.

Walking distance is a predictor of exacerbations in patients with chronic obstructive pulmonary disease

BACKGROUND

Patients with chronic obstructive pulmonary disease (COPD) are responsible for a high utilisation of the health care resources, and the cost is expected to increase. Physiological measures of lung function often fail to describe the impact the symptoms have on exacerbations, days of hospitalisation, and on a patient's health.

METHODS

Twenty-one patients (14 female) with COPD (65 years, 40-79 years) admitted to the Department of Respiratory Medicine in Uppsala, performed a pulmonary function test (FEV(1)% predicted=37) and health status measurement (St. Georges Respiratory Questionnaire, SGRQ) at discharge. Four to six weeks after discharge, when they were in a stable clinical condition, they performed an exercise test (Incremental Shuttle Walk Test, ISWT) to measure their exercise capacity.

RESULTS

Nine of 21 patients (43%) were rehospitalised within 12 month. The mean distance walked in the ISWT was 174m in patients who were hospitalised and 358m in non-hospitalised patients (P<0.001). Oxygen saturation 88% after the ISWT was found in 73% of hospitalised patients in contrast to only 22% in non-hospitalised patients (P<0.05). Activity related health status (SGRQ-activity) was higher (worse) in hospitalised patients than in non-hospitalised patients (75 vs. 50) (P<0.05). The association between walking distance and the risk of rehospitalisation was significant after adjusting for oxygen saturation and health status (hazard risk ratio 0.8 (0.67-0.97) per 10m). This study has shown that walking distance is a good and reliable predictor of rehospitalisations in moderately and severely disabled patients with COPD.

Clinical outcomes of expiratory muscle training in severe COPD patients

The most common symptoms in chronic obstructive pulmonary disease (COPD) patients are breathlessness and exercise limitation. Although both general and inspiratory muscle training have shown clinical benefits, the effects of specific expiratory muscle training remain controversial.

OBJECTIVE

To investigate the effects of expiratory training on lung function, exercise tolerance, symptoms and health-related quality of life in severe COPD patients.

METHODS

Sixteen patients (FEV(1), 28+/-8% pred.) were randomised to either expiratory muscle or sham training groups, both completing a 5-week programme (30 min sessions breathing through an expiratory threshold valve 3 times per week) (50% of their maximal expiratory pressure (MEP) vs. placebo, respectively). Lung function, exercise capacity (bicycle ergometry and walking test), and clinical outcomes (dyspnoea and quality of life (St. George Respiratory Questionnaire (SGRQ)) were evaluated both at baseline and following the training period.

RESULTS

Although lung function remained roughly unchanged after training, exercise capacity, symptoms and quality of life significantly improved. The improvement in both walking distance and the SGRQ score significantly correlated with changes in MEP.

CONCLUSION

Our results confirm that a short outpatient programme of expiratory training can improve symptoms and quality of life in severe COPD patients. These effects could be partially explained by changes in expiratory muscle strength.

Health‐Related Quality of Life Predicts Mortality in Older but Not Younger Patients Following Cardiac Surgery

The investigators assessed preoperative health-related quality of life as a predictor of 6-month mortality after cardiac surgery in older (65 years of age and older) vs. younger patients. Multivariable regression, stratified by age groups, was used to compare the association between preoperative Physical Component Summary and Mental Component Summary scores from the Short Form-36 health status survey and mortality. In multivariable analyses of older patients, lower preoperative Physical Component Summary (odds ratio, 1.54; 95% confidence interval, 1.19-2.00; p=0.01) and Mental Component Summary (odds ratio, 1.26; 95% confidence interval, 1.06-1.49; p=0.03) scores were independently associated with mortality. In contrast, neither Physical Component Summary (p=0.82) nor Mental Component Summary (p=0.79) scores were associated with mortality in the younger subgroup. This study demonstrated that preoperative health status is an independent predictor of mortality following cardiac surgery in older but not younger patients. Preoperative patient self-report of health status may be particularly useful in refining risk stratification and informing decision-making before and following cardiac surgery in older patients.

Health-related quality of life as a predictor of mortality among community-dwelling older persons

Health-related quality of life (HRQOL) measures predict cause-specific mortality, but few studies have explored whether generic self-reported HRQOL measures are independently associated with mortality in community-dwelling older persons. We postulated that a general measure of HRQOL, the short form 36-item questionnaire (SF-36), would be independently predictive of mortality among community-dwelling older persons. To evaluate this hypothesis, we followed a fixed cohort of 4,424 community-dwelling older persons recruited from a 2000 population-based survey in Taiwan until 2003 and investigated whether HRQOL was predictive of 3-year mortality, even after adjusting for traditional clinical risk variables. The data were collected via a door-to-door survey, and interviewers collected information on the subjects' demographics, medical history, utilization of health services, functional ability, falls, and self-reported physical and mental symptoms. Of the 6053 eligible subjects, 4,424 residents agreed to participate in the baseline survey and were contacted in 2003. During the 3-year period, the 3-year cumulative mortality rate for the study population was 5%. Mortality was significantly higher among males (5.57% vs. 4.27%, p = 0.049), and cumulative mortality increased with age (chi (2)-test for trend; chi (2) = 7.734, p = 0.001). For all scales except bodily pain, there was a significant relationship between a 10-point lower baseline score and mortality. Our primary multivariate risk model, which included two summary measures of HRQOL and significant clinical variables, demonstrated that a 10-point decrease in either the baseline Physical Component Summary (PCS) score or the baseline Mental Component Summary (MCS) score was associated with higher mortality (PCS: RR: 1.60, 95% CI: 1.39-1.83; p < 0.001; MCS: RR: 1.16, 95% CI: 1.01-1.34; p = 0.036). The findings suggested that low baseline PCS and MCS scores were important independent risk factors for 3-year mortality among community-dwelling older persons, even after adjusting for other risk factors.

Drawing impairment predicts mortality in severe COPD

BACKGROUND

Cognitive impairment frequently occurs in elderly COPD patients, but little is known about its prognostic implications. We aimed at evaluating the prognostic role of cognitive impairment in patients with severe COPD.

METHODS

Our series consisted of 149 stable patients (mean [+/- SD] age, 68.7 +/- 8.5 years) with COPD and a Pao(2) of < 57 mm Hg at rest (n = 97) or at the end of the 6-min walking test (n = 37) who were enrolled in a prospective observational study. After a multidimensional baseline assessment, patients were followed up by telephone calls for a mean duration of 32.5 +/- 9.2 months (minimal follow-up duration, 24 months); 134 patients were successfully tracked. We used multivariable Cox proportional hazard analysis to identify predictors of death among clinical/functional variables that previously were shown to have prognostic implications and among neuropsychological indexes selected on the basis of univariate analysis.

RESULTS

We observed 29 deaths over a median follow-up time of 32 months. Only the two following variables were independently associated with the outcome: an abnormal score on the copy with landmark test (hazard ratio [HR], 2.93; 95% confidence interval [CI], 1.34 to 6.39); and a 6-min walk distance of < 300 m (HR, 3.46; 95% CI, 1.15 to 10.5). A Pao(2) of < 57 mm Hg at rest (HR, 2.19; 95% CI, 0.93 to 5.18) and an FEV(1) of < 40% predicted (HR, 2.74; 95% CI, 0.99 to 7.57) were nearly significantly associated with the outcome, while Paco(2), body mass index, physical dependence, comorbid diseases, and the impairment of cognitive domains other than drawing impairment were unrelated to the outcome.

CONCLUSIONS

Drawing impairment is a risk factor for mortality and might improve the assessment of hypoxemic COPD patients.

[Functional status and survival in patients with chronic obstructive pulmonary disease following pulmonary rehabilitation]

OBJECTIVES

To study functional status and survival in patients with chronic obstructive pulmonary disease (COPD) following a pulmonary rehabilitation program.

PATIENTS AND METHODS

We assessed lung function, 6-minute walk distance, Borg score for dyspnea upon completion of the 6-minute walk, workload in watts on a cycle ergometer, quality of life using the St George's Respiratory Questionnaire (SGRQ); the body-mass index, airflow obstruction, dyspnea, and exercise capacity (BODE) index; and survival.

RESULTS

One hundred five patients participated in the pulmonary rehabilitation program. The patients had a mean (SD) age of 63.9 (9.3) years, body mass index of 24.5 (4.56) kg/m2, and forced expiratory volume in 1 second (FEV1) of 0.91 (0.46) L. The mean distances walked in 6 minutes were 412.8 (79.4) m before the pulmonary rehabilitation program and 443.46 (81.57) m after rehabilitation. The mean workloads on the cycle ergometer before and after rehabilitation, respectively, were 47.9 (29.6) W and 77.76 (20.88) W. The mean Borg scores were 2.2 (1.37) before and 1.47 (1.37) after rehabilitation, and the SGRQ scores at the same times were 27.63 (16.02) and 25.45 (15.12). Mortality due to respiratory disease (105 months) was 19%. Cumulative survival rates at 1 year, 3 years, and 6 years were 91%, 86.7%, and 6.75%, respectively. Survival was related to an FEV1 greater than 1.02 L (P = .05), a 6-minute walk distance over 448 m before rehabilitation (P = .04) and 454 m after rehabilitation (P = .05), and a workload on the cycle ergometer of over 54 W before rehabilitation (P = .01) and 72 W (P = .02) afterwards. The correlations between survival and both SGRQ and BODE scores were weaker.

CONCLUSIONS

We observed improved exercise capacity, dyspnea ratings, and, to a lesser extent, better SGRQ scores in our COPD patients following pulmonary rehabilitation. The best predictors of survival were FEV1, the 6-minute walk distance, and the cycle ergometer workloads.

Peripheral muscle composition and health status in patients with COPD

STUDY OBJECTIVE

The present study evaluated the relationship between health status (HS) and peripheral muscle histochemical characteristics in chronic obstructive pulmonary disease (COPD), and identified selected independent respiratory and extrapulmonary variables that predicted the HS of these patients.

DESIGN

Cross-sectional study.

SETTING

Outpatient respiratory clinic of a university hospital.

PATIENTS AND METHODS

We studied 29 patients (63+/-10 yrs) with a forced expiratory volume in 1s (FEV1) of 39+/-12%. All patients underwent vastus lateralis muscle biopsies for histochemical analysis. They also had spirometry, arterial blood gas analysis, body mass index (BMI), dyspnea determined with the MMRC scale and responded to the St. George's Respiratory Questionnaire (SGRQ) for HS assessment.

RESULTS

SGRQ total score correlated with fiber type distribution. A stepwise multiple regression identified three independent predictors of SGRQ total score: type I fiber proportion, BMI, and FEV1; r = 0.78 and r2 = 0.61.

CONCLUSIONS

These results indicate that impaired HS in COPD is related to the peripheral muscle changes characterized by less type I fibers proportion. The findings argue in favor of an important contribution of the systemic consequences on the HS in COPD independently from the airflow limitation severity, and help to explain the observation of the poor correlation between the degree of airflow limitation and SGRQ total score.

Gender associated differences in determinants of quality of life in patients with COPD: a case series study

BACKGROUND

The influence of gender on the expression of COPD has received limited attention. Quality of Life (QoL) has become an important outcome in COPD patients. The aim of our study was to explore factors contributing to gender differences in Quality of Life of COPD patients.

METHODS

In 146 men and women with COPD from a pulmonary clinic we measured: Saint George's Respiratory Questionnaire (SGRQ), age, smoking history, PaO2, PaCO2, FEV1, FVC, IC/TLC, FRC, body mass index (BMI), 6 minute walk distance (6MWD), dyspnea (modified MRC), degree of comorbidity (Charlson index) and exacerbations in the previous year. We explored differences between genders using Mann-Whitney U-rank test. To investigate the main determinants of QoL, a multiple lineal regression analysis was performed using backward Wald's criteria, with those variables that significantly correlated with SGRQ total scores.

RESULTS

Compared with men, women had worse scores in all domains of the SGRQ (total 38 vs 26, p = 0.01, symptoms 48 vs 39, p = 0.03, activity 53 vs 37, p = 0.02, impact 28 vs 15, p = 0.01). SGRQ total scores correlated in men with: FEV1% (-0.378, p < 0.001), IC/TLC (-0.368, p = 0.002), PaO2 (-0.379, p = 0.001), PaCO2 (0.256, p = 0.05), 6MWD (-0.327, p = 0.005), exacerbations (0.366, p = 0.001), Charlson index (0.380, p = 0.001) and MMRC (0.654, p < 0.001). In women, the scores correlated only with FEV1% (-0.293, p = 0.013) PaO2 (-0.315, p = 0.007), exacerbations (0.290, p = 0.013) and MMRC (0.628, p < 0.001). Regression analysis (B, 95% CI) showed that exercise capacity (0.05, 0.02 to 0.09), dyspnea (17.6, 13.4 to 21.8), IC/TLC (-51.1, -98.9 to -3.2) and comorbidity (1.7, 0.84 to 2.53) for men and dyspnea (9.7, 7.3 to 12.4) and oxygenation (-0.3, -0.6 to -0.01) for women manifested the highest independent associations with SGRQ scores.

CONCLUSION

In moderate to severe COPD patients attending a pulmonary clinic, there are gender differences in health status scores. In turn, the clinical and physiological variables independently associated with those scores differed in men and women. Attention should be paid to the determinants of QoL scores in women with COPD.

Mortality in COPD patients discharged from hospital: the role of treatment and co-morbidity

BACKGROUND

The aim of this study was to analyse mortality and associated risk factors, with special emphasis on health status, medications and co-morbidity, in patients with chronic obstructive pulmonary disease (COPD) that had been hospitalized for acute exacerbation.

METHODS

This prospective study included 416 patients from each of the five Nordic countries that were followed for 24 months. The St. George's Respiratory Questionnaire (SGRQ) was administered. Information on treatment and co-morbidity was obtained.

RESULTS

During the follow-up 122 (29.3%) of the 416 patients died. Patients with diabetes had an increased mortality rate [HR = 2.25 (1.28-3.95)]. Other risk factors were advanced age, low FEV1 and lower health status. Patients treated with inhaled corticosteroids and/or long-acting beta-2-agonists had a lower risk of death than patients using neither of these types of treatment.

CONCLUSION

Mortality was high after COPD admission, with older age, decreased lung function, lower health status and diabetes the most important risk factors. Treatment with inhaled corticosteroids and long-acting bronchodilators may be associated with lower mortality in patients with COPD.

Comparison of Australian and international guidelines for grading severity of chronic obstructive pulmonary disease

AIM

To compare grading of chronic obstructive pulmonary disease (COPD) using Australian guidelines Confirm diagnosis, Optimize function, Prevent deterioration, Develop a self-management plan and manage eXacerbations (COPD-X) versus Global initiative for Obstructive Lung Disease (GOLD) guidelines and to assess whether this is associated with differences in other health domains affected by COPD. Adult outpatients (n = 61) with COPD were studied using lung function measurements, six-minute walk test and body composition assessments. Subjects also completed self-rated dyspnoea scores and health-related quality-of-life scales. For each patient, COPD severity was graded using both COPD-X and GOLD guidelines, and results were collectively analysed. If significant discrepancies were observed, comparisons of other health domains were carried out. After grading severity using COPD-X and GOLD guidelines, significant discrepancies were noted. Of nine subjects with no disease (normal) based on COPD-X, seven were judged to be 'mild' according to GOLD. Similarly, 11 of 12 patients with mild disease (COPD-X) had 'moderate' disease judged by GOLD, and 9 of 23 with moderate severity (COPD-X) had 'severe' COPD using GOLD. Finally, 6 of 17 patients with COPD-X-rated severe disease had 'very severe' disease using the GOLD criteria. Among patients with COPD-X severe disease, those with GOLD discordant (very severe) severity had a poorer quality of life compared with those with GOLD concordant (severe) severity (P = 0.006). Similarly, there was also a trend towards lower six-minute walk test distance and greater subjective dyspnoea in GOLD very severe patients compared with GOLD severe patients. Significant discrepancies in grading of severity exist between Australian and international COPD guidelines. Current Australian guidelines for severity grading may not fully reflect the effect COPD has on other key domains of health.

The effect of tiotropium bromide on health-related quality of life in chronic obstructive pulmonary disease

Tiotropium bromide is a once-daily anticholinergic recommended for maintenance treatment of chronic obstructive pulmonary disease. The 24-h bronchodilation in patients with chronic obstructive pulmonary disease achieved with tiotropium treatment is currently unique. However, there is an increasing demand for proven efficacy in parameters of more direct interest to patients, in addition to physiological parameters. This article reviews the data currently available on the efficacy of tiotropium to improve the health-related quality of life of patients with chronic obstructive pulmonary disease.

Estimating the cost-effectiveness of fluticasone propionate for treating chronic obstructive pulmonary disease in the presence of missing data

OBJECTIVES

To explore the cost-effectiveness of fluticasone propionate (FP) for the treatment of chronic obstructive pulmonary disease (COPD), we estimated costs and quality-adjusted life-years (QALYs) over 3 years, based on an economic appraisal of a previously reported clinical trial (Inhaled Steroids in Obstructive Lung Disease in Europe [ISOLDE]).

METHODS

Seven hundred forty-two patients enrolled in the ISOLDE trial who received either FP or placebo had data available on health-care costs and quality of life over the period of the study. The SF-36-based utility scores for quality of life were used to calculate QALYs. A combined imputation and bootstrapping procedure was employed to handle missing data and to estimate statistical uncertainty in the estimated cumulative costs and QALYs over the study period. The imputation approach was based on propensity scoring and nesting this approach within the bootstrap ensured that multiple imputations were performed such that statistical estimates included imputation uncertainty.

RESULTS

Complete data were available on mortality within the follow-up period of the study and a nonsignificant trend toward improved survival of 0.06 (95% confidence interval [CI]-0.01 to 0.15) life-years was observed. In an analysis based on a propensity scoring approach to missing data we estimated the incremental costs of FP versus placebo to be 1021 sterling pound(95% CI 619-1338 sterling pound) with an additional effect of 0.11 QALYs (CI 0.04-0.20). Cost-effectiveness estimates for the within-trial period of 17,700 sterling pound per life-year gained (6900 sterling pound to infinity) and 9500 sterling pound per QALY gained (CI 4300-26,500 sterling pound) were generated that include uncertainty due to the imputation process. An alternative imputation approach did not materially affect these estimates.

CONCLUSIONS

Previous analyses of the ISOLDE study showed significant improvement on disease-specific health status measures and a trend toward a survival advantage for treatment with FP. This analysis shows that joint considerations of quality of life and survival result in a substantial increase in QALYs favoring treatment with FP. Based on these data, the inhaled corticosteroid FP appears cost-effective for the treatment of COPD. Confirmation or refutation of this result may be achieved once the Towards a Revolution in COPD Health (TORCH) study reports, a large randomized controlled trial powered to detect mortality changes associated with the use of FP alone, or in combination with salmeterol, which is also collecting resource use and utility data suitable for estimating cost-effectiveness.

Do health-status measures play a role in improving treatment in chronic obstructive pulmonary disease?

During the past few decades, health status has become increasingly important in the clinical research of chronic obstructive pulmonary disease. The use of health-status questionnaires in routine practice can enhance understanding about the impact of the disease on the patient, improve standardisation and increase compliance through increased patient satisfaction. However, before health-status measurement in individual patients can be used in routine practice, questionnaires have to be validated on an individual level. In this article, the authors suggest a new method of assessing this individual validity, to enhance the use of health-status instruments in daily clinical practice, and thus improve treatment in chronic obstructive pulmonary disease.

Predictors of mortality in patients with emphysema and severe airflow obstruction

PURPOSE

Limited data exist describing risk factors for mortality in patients having predominantly emphysema.

SUBJECTS AND METHODS

A total of 609 patients with severe emphysema (ages 40-83 yr; 64.2% male) randomized to the medical therapy arm of the National Emphysema Treatment Trial formed the study group. Cox proportional hazards regression analysis was used to investigate risk factors for all-cause mortality. Risk factors examined included demographics, body mass index, physiologic data, quality of life, dyspnea, oxygen utilization, hemoglobin, smoking history, quantitative emphysema markers on computed tomography, and a modification of a recently described multifunctional index (modified BODE).

RESULTS

Overall, high mortality was seen in this cohort (12.7 deaths per 100 person-years; 292 total deaths). In multivariate analyses, increasing age (p=0.001), oxygen utilization (p=0.04), lower total lung capacity % predicted (p=0.05), higher residual volume % predicted (p=0.04), lower maximal cardiopulmonary exercise testing workload (p=0.002), greater proportion of emphysema in the lower lung zone versus the upper lung zone (p=0.005), and lower upper-to-lower-lung perfusion ratio (p=0.007), and modified BODE (p=0.02) were predictive of mortality. FEV1 was a significant predictor of mortality in univariate analysis (p=0.005), but not in multivariate analysis (p=0.21).

CONCLUSION

Although patients with advanced emphysema experience significant mortality, subgroups based on age, oxygen utilization, physiologic measures, exercise capacity, and emphysema distribution identify those at increased risk of death.

Health status measurement in COPD: the minimal clinically important difference of the clinical COPD questionnaire

BACKGROUND

Patient-reported outcomes (PRO) questionnaires are being increasingly used in COPD clinical studies. The challenge facing investigators is to determine what change is significant, ie what is the minimal clinically important difference (MCID). This study aimed to identify the MCID for the clinical COPD questionnaire (CCQ) in terms of patient referencing, criterion referencing, and by the standard error of measurement (SEM).

METHODS

Patients were > or = 40 years of age, diagnosed with COPD, had a smoking history of >10 pack-years, and were participating in a randomized, controlled clinical trial comparing intravenous and oral prednisolone in patients admitted with an acute exacerbation of COPD. The CCQ was completed on Days 1-7 and 42. A Global Rating of Change (GRC) assessment was taken to establish the MCID by patient referencing. For criterion referencing, health events during a period of 1 year after Day 42 were included in this analysis.

RESULTS

210 patients were recruited, 168 completed the CCQ questionnaire on Day 42. The MCID of the CCQ total score, as indicated by patient referencing in terms of the GRC, was 0.44. The MCID of the CCQ in terms of criterion referencing for the major outcomes was 0.39, and calculation of the SEM resulted in a value of 0.21.

CONCLUSION

This investigation, which is the first to determine the MCID of a PRO questionnaire via more than one approach, indicates that the MCID of the CCQ total score is 0.4.

Exacerbations, Hospital Admissions and Impaired Health Status in Chronic Obstructive Pulmonary Disease

Impaired health status may be a risk factor for frequent exacerbations and hospital admission and, in turn, exacerbations and admissions may further impair the health status of patients with COPD. We have investigated the variables associated with frequent exacerbations (3 or more per year) and admission, with particular interest in health status, in a cohort of ambulatory patients with moderate to severe COPD attended by chest physicians in Spain. A total of 227 investigators included 1057 patients with a mean predicted FEV1 of 41.8%. The mean total score on the St. George's Respiratory Questionnaire (SGRQ) was 47.9 units, and 300 patients (28.4%) had 3 or more exacerbations the previous year and 344 (32.6%) were admitted at least once during the same period. In multivariate analysis only the SGRQ total score was significantly associated with both frequent exacerbations (OR = 1.04; 95% CI = 1.01-2.12; p<0.0001) and admission (OR = 1.01; 95% CI = 1.00-1.02; p = 0.0008). Other variables significantly associated with frequent exacerbations were chronic mucus hypersecretion, increased baseline dyspnea, comorbidity, GOLD stage IV and treatment with inhaled corticosteroids. Variables associated with admission were lower educational level, increased number of exacerbations, use of long-term oxygen therapy and use of short acting beta-2 agonists. An impaired health status is associated with an increased number of exacerbations and with admission to hospital in the previous year. These results, together with previous studies, confirm that impairment in health status in COPD is both a marker of risk for, and a consequence of, frequent exacerbations and admissions.

Survival of patients with chronic obstructive pulmonary disease due to biomass smoke and tobacco

RATIONALE

Women exposed chronically to biomass develop airflow limitation, as tobacco smokers do, but their clinical profile and survival have not been described in detail.

OBJECTIVE

To determine the clinical profile, survival, and prognostic factors of chronic obstructive pulmonary disease associated with biomass exposure and tobacco smoking.

METHODS

During a 7-yr period (1996-2003), a consecutive series of 520 patients were recruited and followed up at the COPD Clinic of the National Institute of Respiratory Diseases. Prognostic factors of survival were evaluated taking into account the interaction between sex and exposure.

MEASUREMENTS

Spirometry, arterial blood gases and oxygen saturation, body mass index, exercise capacity, and health-related quality of life were performed at baseline. The main outcome was survival.

MAIN RESULTS

A total of 481 patients were followed up. The patients in the biomass group, mainly women (84%), were older and shorter and had a greater body mass index than those in the tobacco group (p < 0.0001). Airflow obstruction was more severe in smokers (p < 0.001). Quality of life and distance walked showed similar abnormalities in both groups. In the multivariable Cox regression analysis including an interaction term exposure-sex, we found that age (relative risk [RR], 1.02; 95% confidence interval [CI], 1.02-1.07), FEV(1) as percentage of predicted (RR, 0.96; 95% CI, 0.96-0.99), body mass index (RR, 0.95; 95% CI, 0.90-1.01), and oxygen saturation (RR, 0.96; 95% CI, 0.92-0.99) were predictors of mortality but not exposure or sex.

CONCLUSIONS

Women exposed domestically to biomass develop chronic obstructive pulmonary disease with clinical characteristics, quality of life, and increased mortality similar in degree to that of tobacco smokers.

Future perspectives in COPD

The pathophysiology of chronic obstructive pulmonary disease (COPD) is complex. The development of a multidimensional index--such as the BODE index--provides a means of classifying patients with COPD that also correlates with their prognosis. The individual components of the BODE index--body mass index (B), airflow obstruction (O) dyspnoea (D) and exercise capacity (E)--incorporate the pulmonary as well as the systemic effects seen in patients with COPD. Recent research has focussed on examining these impairments (including those of metabolism and inflammation) more carefully, and determining the effects of treatment on both the systemic and physiological aspects of COPD. Ongoing research initiatives by the public and private sector will contribute to our understanding of the disease processes underlying COPD, our understanding of the benefits associated with commonly used pharmacotherapies, as well as laying the foundations for the development of new agents and therapeutic tools. Advances in the use of pharmacotherapy have been mirrored by research to better define the benefits associated with pulmonary rehabilitation. Many questions remain to be answered, but a comprehensive approach is now considered essential to the life-long management of COPD, and will undoubtedly reduce the considerable socio-economic burden of COPD.

Inhaled corticosteroids and mortality in chronic obstructive pulmonary disease

BACKGROUND

Clinical studies suggest that inhaled corticosteroids reduce exacerbations and improve health status in chronic obstructive pulmonary disease (COPD). However, their effect on mortality is unknown.

METHODS

A pooled analysis, based on intention to treat, of individual patient data from seven randomised trials (involving 5085 patients) was performed in which the effects of inhaled corticosteroids and placebo were compared over at least 12 months in patients with stable COPD. The end point was all-cause mortality.

RESULTS

Overall, 4% of the participants died during a mean follow up period of 26 months. Inhaled corticosteroids reduced all-cause mortality by about 25% relative to placebo. Stratification by individual trials and adjustments for age, sex, baseline post-bronchodilator percentage predicted forced expiratory volume in 1 second, smoking status, and body mass index did not materially change the results (adjusted hazard ratio (HR) 0.73; 95% confidence interval (CI) 0.55 to 0.96). Although there was considerable overlap between subgroups in terms of effect sizes, the beneficial effect was especially noticeable in women (adjusted HR 0.46; 95% CI 0.24 to 0.91) and former smokers (adjusted HR 0.60; 95% CI 0.39 to 0.93).

CONCLUSIONS

Inhaled corticosteroids reduce all-cause mortality in COPD. Further studies are required to determine whether the survival benefits persist beyond 2-3 years.

Baseline pulmonary function and quality of life 9 years later in a middle-aged Chinese population

STUDY OBJECTIVE

This research examined the association of baseline pulmonary function with future quality of life (QOL).

METHODS

We collected baseline pulmonary function data in 1993 and 1994, and assessed QOL using the Chinese 35-Item Quality of Life Instrument in 2002 in a cohort of 1,356 participants. We used Pearson correlation analysis, multivariate analysis of variance, and multivariate linear regression analysis to assess the relationship between pulmonary function and QOL.

RESULTS

The baseline percentage of age- and height-predicted FEV1 (FEV1%) was significantly correlated with the resurvey total QOL score (r = 0.126, p < 0.001) and with QOL scores for the general (r = 0.074, p = 0.006), physical (r = 0.085, p = 0.002), independence (r = 0.178, p < 0.001), and psychological (r = 0.064, p = 0.018) domains but not with the social and environmental domains after adjusting for age and sex. These associations were weaker for the percentage of age- and height-predicted FVC. Multiple linear regression showed that the above associations were independent of baseline and resurvey smoking status. Inclusion of respiratory symptoms in the model reduced the regression coefficients from 0.82 to 0.41 for the total QOL score and from 1.43 to 0.94 for the independence domain score, for a 10% change in FEV1%. The age- and sex-adjusted mean total QOL scores were 78, 76, 76, and 69, respectively (p < 0.001), for the groups of normal, symptomatic only, impaired pulmonary function only, and both symptomatic and impaired pulmonary function. This trend was also significant for the general, physical, independence, and psychological domain scores.

CONCLUSION

Impaired baseline pulmonary function has a significant negative impact on QOL in later life that is independent of age, sex, height, and smoking status and is largely mediated through the development of chronic respiratory symptoms.

Gender and COPD in patients attending a pulmonary clinic

OBJECTIVES

To compare gender differences in the clinical expression of COPD patients attending a pulmonary clinic.

MATERIALS AND METHODS

We compared 53 FEV1-matched men and women with COPD attending a pulmonary clinic. We studied age, smoking pack-years history, Pa(O2), Pa(CO2), functional residual capacity, body mass index (BMI), dyspnea, 6-min walk distance (6MWD), health-related quality of life, presence of comorbidities, and exacerbations in the previous year.

RESULTS

Women were younger (57 years vs 65 years, p < 0.05), smoked less (48 pack-years vs 69 pack-years, p < 0.05), had better Pa(O2) (74 mm Hg vs 67 mm Hg, p < 0.05), lower Pa(CO2) (40 mm Hg vs 45 mm Hg, p < 0.05), lower BMI (25 vs 28, p < 0.05), more exacerbations in the last year (1 vs 0, p < 0.05), and fewer comorbidities (Charlson score 2 vs score 4, p < 0.05) than men. Even though women had the same FEV1, better oxygenation, better Pa(CO2), and fewer comorbidities, they performed poorer in walking distance (6MWD percentage of predicted, 87% vs 105%; p = 0.05), had worse quality-of-life scores (Saint George's Respiratory Questionnaire [SGRQ] symptoms score, 51 vs 41, p < 0.05; SGRQ activity score, 58 vs 47, p < 0.05), and had a higher degree of dyspnea (Modified Medical Research Council scale > 2, 28% vs 6%, p = 0.05).

CONCLUSIONS

In a population of patients with COPD attending a pulmonary clinic, there are gender-related differences in the clinical expression of COPD that need further attention.

Measuring the effects of COPD on the patient

Evaluation of the effectiveness of treatment for chronic obstructive pulmonary disease (COPD) requires the assessment of both clinical and physiological measures. Parameters such as the forced expiratory volume in 1 s are well established in providing an indication of the degree of airflow limitation. However, additional measurements, such as dyspnoea, functional status and health status, are required to provide a complete picture of COPD. Indeed, dyspnoea is the predominant symptom of COPD experienced by the patient, which treatment is designed to reduce. Methods of assessing dyspnoea have developed over the previous five decades. The most widely used instruments for assessing the impact of dyspnoea are the baseline dyspnoea index, the transition dyspnoea index and the Medical Research Council Questionnaire. A more comprehensive approach to the assessment of disability caused by dyspnoea and fatigue is provided by assessments of functional status, such as the pulmonary functional status and dyspnoea questionnaire. Respiratory-specific health status questionnaires, such as the St. George's Respiratory Questionnaire, attempt to capture the wide range of effects of COPD into a single score that reflects the overall impact of the disease. Developing the means to measure the effects of COPD is important, both in terms of understanding disease pathophysiology for research purposes, and in terms of accurately assessing the effects of treatment on the patient. Future developments will include computerising these methodologies to permit faster and more individual patient-centred measurements.

Evaluating the effectiveness of combination therapy to prevent COPD exacerbations: the value of NNT analysis

The effective prevention of exacerbations in patients with chronic obstructive pulmonary disease (COPD) has the potential to improve patients' health-related quality of life, reduce rates of hospitalisation and mortality and lower healthcare costs. Several pharmacological agents, including inhaled corticosteroid/long-acting beta2-agonist combination therapies, have demonstrated beneficial effects on COPD exacerbations. The number needed to treat (NNT) analysis is a simple, concise method that allows physicians to quantify directly the benefits that alternative treatment options have on disease outcomes in terms of the number of patients who need to be treated before a benefit is observed. This review evaluates the applicability and clinical relevance of NNT analysis for determining the effectiveness of combination therapies against COPD exacerbations, focusing on budesonide/ formoterol in the same inhaler. Physicians are encouraged to consider NNT data within the context of their limitations and in conjunction with other analytical methods when selecting treatments for patients with COPD.

La calidad de vida en los pacientes con enfermedad pulmonar obstructiva crónica: criterios de cuantificación y repercusiones terapéuticas

Chronic obstructive pulmonary disease (COPD) is one of the most prevalent chronica diseases in developed countries. Prognosis of the disease is mainly determined by the degree of air flow obstruction. However, other factors, such as degree of deterioration of the quality of life related with health have been demonstrated to be significantly correlated with morbidity and mortality in COPD. Thus, one of the main objectives of the treatment of COPD is to improve the health condition of the patients, beyond the possible improvement of the lung function. New drugs developed for the treatment of COPD have shown a different impact on the health condition of those affected by COPD.

The Dartmouth COOP Charts: a simple, reliable, valid and responsive quality of life tool for chronic obstructive pulmonary disease

The negative impact of chronic obstructive pulmonary disease (COPD) on health-related quality of life (HRQL) is substantial. Measurement of HRQL is increasingly advocated in clinical practice; traditional outcome measures such as lung function are poorly responsive. However many HRQL tools are not user-friendly in the clinic setting. Hence HRQL is often neglected. The Dartmouth Cooperative Functional Assessment Charts (COOP) have the requisite attributes of a tool suitable for routine clinical practice: they are simple, reliable, quick and easy to perform and score and well accepted. We aimed to determine the reliability, validity and responsiveness of the COOP in patients with significant COPD. HRQL was assessed during a prospective, randomised, placebo-controlled, double-blind, 12 week cross-over interventional study of ambulatory oxygen in patients (n = 50) with COPD. Test-retest reliability of the COOP domains was only modest however it was measured over a 2 month period. Significant correlations ranging between 0.4 and 0.8 were observed between all comparable domains of the COOP and the Medical Outcomes Study 36-item Short-form Health Survey, Chronic Respiratory Questionnaire (CRQ) and Hospital Anxiety and Depression (HAD) scale. Following ambulatory oxygen significant improvements were noted in all CRQ and HAD domains. Several domains of the generic SF-36 (role emotional, social functioning, role-physical) showed significant improvements. Comparable domains of the COOP (social activities, feelings) also showed significant improvements. The COOP change in health domain improved very significantly. The COOP is a simple, reliable HRQL tool which proved valid and responsive in our study population of COPD patients and may have a valuable role in routine clinical practice.

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.

Severe acute exacerbations and mortality in patients with chronic obstructive pulmonary disease

BACKGROUND

Patients with chronic obstructive pulmonary disease (COPD) often present with severe acute exacerbations requiring hospital treatment. However, little is known about the prognostic consequences of these exacerbations. A study was undertaken to investigate whether severe acute exacerbations of COPD exert a direct effect on mortality.

METHODS

Multivariate techniques were used to analyse the prognostic influence of acute exacerbations of COPD treated in hospital (visits to the emergency service and admissions), patient age, smoking, body mass index, co-morbidity, long term oxygen therapy, forced spirometric parameters, and arterial blood gas tensions in a prospective cohort of 304 men with COPD followed up for 5 years. The mean (SD) age of the patients was 71 (9) years and forced expiratory volume in 1 second was 46 (17)%.

RESULTS

Only older age (hazard ratio (HR) 5.28, 95% CI 1.75 to 15.93), arterial carbon dioxide tension (HR 1.07, 95% CI 1.02 to 1.12), and acute exacerbations of COPD were found to be independent indicators of a poor prognosis. The patients with the greatest mortality risk were those with three or more acute COPD exacerbations (HR 4.13, 95% CI 1.80 to 9.41).

CONCLUSIONS

This study shows for the first time that severe acute exacerbations of COPD have an independent negative impact on patient prognosis. Mortality increases with the frequency of severe exacerbations, particularly if these require admission to hospital.

Assessment of progression of COPD: report of a workshop held in Leuven, 11-12 March 2004

Recently performed long term trials have enhanced the insight into the assessment of progression of COPD. The present review focuses on the initial assessment of COPD in general practice and the assessment of disease progression. Several variables may be used to assess this progression, all of which are associated with significant methodological problems. Finding the appropriate mix of outcome measures to capture all aspects of disease progression is a significant challenge.

El Cuestionario de Salud SF-36 español: una década de experiencia y nuevos desarrollos

OBJECTIVE

The Short Form-36 Health Survey (SF-36) is one of the most widely used and evaluated generic health-related quality of life (HRQL) questionnaires. After almost a decade of use in Spain, the present article critically reviews the content and metric properties of the Spanish version, as well as its new developments.

METHODS

A review of indexed articles that used the Spanish version of the SF-36 was performed in Medline (PubMed), the Spanish bibliographic databases IBECS and IME. Articles that provided information on the measurement model, reliability, validity, and responsiveness to change of the instrument were selected.

RESULTS

Seventy-nine articles were found, of which 17 evaluated the metric characteristics of the questionnaire. The reliability of the SF-36 scales was higher than the suggested standard (Cronbach's alpha) of 0.7 in 96% of the evaluations. Grouped evaluations obtained by meta-analysis were higher than 0.7 in all cases. The SF-36 showed good discrimination among severity groups, moderate correlations with clinical indicators, and high correlations with other HRQL instruments. Moreover, questionnaire scores predicted mortality and were able to detect improvement due to therapeutic interventions such as coronary angioplasty, benign prostatic hyperplasia surgery, and non-invasive positive pressure home ventilation. The new developments (norm-based scoring, version 2, the SF-12 and SF-8) improved both the metric properties and interpretation of the questionnaire.

CONCLUSIONS

The Spanish version of the SF-36 and its recently developed versions is a suitable instrument for use in medical research, as well as in clinical practice.

Roflumilast: the evidence for its clinical potential in the treatment of chronic obstructive pulmonary disease

INTRODUCTION

Chronic obstructive pulmonary disease (COPD), characterized by a progressive deterioration of lung function caused primarily by the inhalation of toxic substances, is a leading cause of morbidity and mortality worldwide. Current treatment options for the management of its symptoms include the use of bronchodilators and glucocorticoid agents that are not universally beneficial and which are associated with limitations. Phosphodiesterase-4 (PDE4) inhibitors are a novel class of antiinflammatory agents being developed for COPD treatment.

AIMS

The purpose of this article is to review the clinical potential of roflumilast, a PDE4 inhibitor currently in phase III clinical trials, in the management of patients with COPD.

EVIDENCE REVIEW

Phase II studies indicate that roflumilast can be given orally once daily. Preliminary evidence from two phase III, randomized, double-blind, placebo-controlled studies suggest that roflumilast improves or stabilizes lung function, as measured by forced expiratory volume in 1 s and 6 s (FEV(1) and FEV(6)), forced vital capacity (FVC), and peak expiratory flow (PEF) in patients with COPD. Improvements in COPD exacerbation rate were also reported in these trials. Quality of life, as measured by the St George's Respiratory Questionnaire, also improved with roflumilast treatment. Clinical studies to date suggest that roflumilast is well tolerated.

CLINICAL POTENTIAL

Current evidence supports the use of roflumilast in the management of COPD as shown by improvements in patients' symptoms and quality of life, and good tolerability profile. Its once-daily oral dosing regimen is unique among current therapies for COPD. This potential and the place of roflumilast in the stepwise management of the disease need to be confirmed as further evidence is published. Additional evidence will also be welcome to determine if its mechanism of action moderates the progression of lung function deterioration.

Inspiratory-to-Total Lung Capacity Ratio Predicts Mortality in Patients with Chronic Obstructive Pulmonary Disease

Static lung hyperinflation has important clinical consequences in patients with chronic obstructive pulmonary disease. We analyzed the power of lung hyperinflation as measured by the inspiratory capacity-to-total lung capacity ratio (IC/TLC) to predict mortality in a cohort of 689 patients with chronic obstructive pulmonary disease (95% males; FEV(1), 1.17 L) with a mean follow-up of 34 months. We also compared the predictive value of IC/TLC with that of the BODE (body mass index, airflow obstruction, dyspnea, exercise performance) Index. Subjects who died (183; 27%) were older; had lower body mass index, FEV(1), and IC/TLC ratio; walked less in the 6-minute walking distance; and had more dyspnea, a higher BODE Index, and comorbidity (p < 0.001). On the basis of logistic regression analysis, IC/TLC was found to be a good and independent predictor of all-cause and respiratory mortality. On the basis of receiver operating characteristic Type II curves, IC/TLC compared favorably with FEV(1) and predicted mortality independently of the BODE Index. We conclude that IC/TLC is an independent risk factor for mortality in subjects with chronic obstructive pulmonary disease. We propose that this ratio be considered in the assessment of patients with chronic obstructive pulmonary disease.