Respiratory Medicine: COPD Update最新文献

Background

Clinical trials measure exacerbations of chronic obstructive pulmonary disease (COPD) inconsistently. A study was undertaken to determine if different methods for ascertaining and analysing COPD exacerbations lead to biased estimates of treatment effects.

Methods

Information on the methods used to count, analyse and report COPD exacerbation rates was abstracted from clinical trials of long-acting bronchodilators or long-acting bronchodilator/inhaled steroid combination products published between 2000 and 2006. Data from the Canadian Optimal Therapy of COPD Trial was used to illustrate how different analytical approaches can affect the estimate of exacerbation rates and their confidence intervals.

Results

22 trials (17,156 patients) met the inclusion criteria and were reviewed. None of the trials adjudicated exacerbations or determined independence of events. 14/22 studies (64%) introduced selection bias by not analysing outcome data for subjects who prematurely stopped study medications. Only 31% of trials used time-weighted analyses to calculate the mean number of exacerbations/patient-year and only 15% accounted for between-subject variation. In the Canadian Optimal Therapy of COPD Trial the rate ratio for exacerbations/patient-year was 0.85 when all data were included in a time-weighted analysis, but was overestimated as 0.79 when data for those who prematurely stopped study medications were excluded and was further overestimated as 0.46 when a time-weighted analysis was not conducted; p values ranged from 0.03 to 0.24 depending on how exacerbations were determined and analysed.

Conclusions

Clinical trials have used widely different methods to define and analyse COPD exacerbations and this can lead to biased estimates of treatment effects. Future trials should strive to include blinded adjudication and assessment of the independence of exacerbation events, and trials should report time-weighted intention-to-treat analyses with adjustments for between-subject variation in COPD exacerbations.

Reproduced with permission from the BMJ Publishing Group.

Background

Cardiovascular disease is a major cause of death in patients with chronic obstructive pulmonary disease (COPD) and predicts hospitalisation for acute exacerbation, in-hospital death and post-discharge mortality. Although beta blockers improve cardiovascular outcomes, patients with COPD often do not receive them owing to concerns about possible adverse pulmonary effects. There are no published data about beta blocker use among inpatients with COPD exacerbations. A study was undertaken to identify factors associated with beta blocker use in this setting and to determine whether their use is associated with decreased in-hospital mortality.

Methods

Administrative data from the University of Alabama Hospital were reviewed and patients admitted between October 1999 and September 2006 with an acute exacerbation of COPD as a primary diagnosis or as a secondary diagnosis with a primary diagnosis of acute respiratory failure were identified. Demographic data, co-morbidities and medication use were recorded and subjects receiving beta blockers were compared with those who did not. Multivariate regression analysis was performed to determine predictors of in-hospital death after controlling for known covariates and the propensity to receive beta blockers.

Resutls

825 patients met the inclusion criteria. In-hospital mortality was 5.2%. Those receiving beta blockers (n=142) were older and more frequently had cardiovascular disease than those who did not. In multivariate analysis adjusting for potential confounders including the propensity score, beta blocker use was associated with reduced mortality (OR=0.39; 95% CI 0.14 to 0.99). Age, length of stay, number of prior exacerbations, the presence of respiratory failure, congestive heart failure, cerebrovascular disease or liver disease also predicted in-hospital mortality (p<0.05).

Conclusions

The use of beta blockers by inpatients with exacerbations of COPD is well tolerated and may be associated with reduced mortality. The potential protective effect of beta blockers in this population warrants further study.

Reproduced with permission from the BMJ Publishing Group.

Although feelings of anxiety and depression are common in patients with chronic obstructive pulmonary disease (COPD), estimates of their prevalence vary considerably. This probably reflects the variety of scales and methods used to measure such symptoms. Regardless of whether anxiety and depression are considered separately or as a single construct, their impact on COPD patients is important. A heightened experience of dyspnoea is likely to be a contributing factor to anxiety. Feelings of depression may be precipitated by the loss and grief associated with the disability of COPD. Smoking has been associated with nicotine addiction, and the factors that contribute to smoking may also predispose to anxiety and depressive disorders. Randomised controlled trials indicate that exercise training and carefully selected pharmacological therapy are often effective in ameliorating anxiety and depression. Most medical illnesses are influenced by the psychological responses and coping mechanisms that patients use. However, anxiety and depression are associated with dyspnoea, fatigue and altered sleep, all of which also occur in COPD. An understanding of the psychological history and coping mechanisms of patients and the role of anxiety and depressive reactions to illness may enable clinicians to reduce these symptoms and improve quality of life among patients with COPD.

Reproduced with permission from European Respiratory Society Journals Ltd.

Patients with chronic obstructive pulmonary disease (COPD) are at increased risk of cardiovascular disease, exacerbations of which increase strain on the heart. The prognostic value of elevated circulating levels of cardiac Troponins seen during COPD exacerbations has been investigated. From the Akershus hospital database, 897 patients discharged after treatment for COPD exacerbation in the period 2000-2003 were identified and followed-up until June 30, 2005. Median observation time was 1.9 yrs. In 396 patients, measurements of cardiac-specific troponin T (cTnT) were available. Levels of cTnT >/=0.04 mug.L(−1) were considered elevated. Clinical data were retrieved from patient records and date of death was obtained from the Norwegian National Registry. In order to balance the nonrandomised nature of available cTnT measurements, an exposure propensity score (EPS) for cTnT sampling was calculated and used in regression analyses. After adjusting for EPS in Cox regression analyses, elevated cTnT was significantly associated with increased all-cause mortality in the observation period, with a hazard ratio of 1.64 (95% confidence interval 1.15–2.34). In conclusion, chronic obstructive pulmonary disease patients with elevated cardiac-specific Troponin T during exacerbation are at increased risk of death after discharge.

Reproduced with permission from European Respiratory Society Journals Ltd.

It is currently fashionable to believe that patients with chronic diseases can be managed safely, effectively and more cheaply entirely in the community. In the UK, current commissioning and financial models encourage the development of services to provide continuing care as well as to replace acute care traditionally provided by hospitals. For some patients, this may be appropriate, but there is a danger of taking it too far and for patients to be denied appropriate input from specialists.

Reproduced with permission from the BMJ Publishing Group.

Exercise tests are widely used to assess response to therapeutic interventions in patients with COPD. The choice of test depends on (1) the outcome(s) of interest, which may include changes in maximum, submaximum or functional exercise capacity and/or the mechanisms underpinning any changes; (2) the intervention being assessed; (3) the patient's characteristics and (4) the resources available. These factors will be discussed in relation to cycling and walking tests, as these are the tests most commonly used in clinical practice and research.

Reproduced with permission from Sage Publications Ltd.

Background

To increase recognition of airflow obstruction in primary care, we compared two models of spirometry delivery in a target group at risk of chronic obstructive pulmonary disease (COPD).

Methods

A 6-month qualitative/quantitative cluster randomized study in eight practices compared opportunistic spirometry by “visiting trained nurses” (TN) with optimized “usual care” (UC) from general practitioners (GPs) for smokers and ex-smokers, aged over 35 years. Outcomes were: spirometry uptake and quality, new diagnoses of COPD and GPs’ experiences of spirometry.

Results

In the eligible target population, 531/904 (59%) patients underwent spirometry in the TN model and 87/1130 (8%) patients in the UC model (p<0.0001). ATS spirometry standards for acceptability and reproducibility were met by 76% and 44% of tests in the TN and UC models, respectively (p<0.0001). One hundred and twenty-five (24%) patients tested with the TN model and 38 (44%) with the UC model reported a pre-existing respiratory diagnosis (p<0.0001). Three months after spirometry, when the ratio of forced expiratory volume in 1 s/forced vital capacity (FEV(1)/FVC) was <0.7 and no prior COPD diagnosis was reported, nine (8%) participants had a new doctor recorded COPD diagnosis in practices with the TN model and two (8%) participants in practices with the UC model. Mislabeling of participants with a diagnosis of COPD when FEV(1)/FVC was > or =0.7 was present in both models prior to and after spirometry. GPs valued high-quality spirometry and increased testing of patients at risk of COPD in the TN model. They identified limitations, including the need for better systematic follow-up of abnormal spirometry and support with interpretation, which may explain persisting underdiagnosis of COPD in practice records.

Conclusions

Although opportunistic testing by visiting trained nurses substantially increased and improved spirometry performance compared with usual care, translating increased detection of airflow obstruction into diagnosis of COPD requires further development of the model. Trial registration number: Australian Clinical Trials Registry: registration no. 12605000019606.

Reproduced with permission from the BMJ Publishing Group.

Introduction: Mortality rates after hip fracture have not declined in 20 years. We assessed the impact of chronic obstructive pulmonary disease (COPD) on mortality after hip fracture, and compared mortality in this cohort to persons without hip fracture in a population-based prospective cohort study.

Methods: Using Danish health care registries, we identified persons >/=40 years old with first-time hospitalization for hip fracture between 1/1/1998 and 1/31/2003. Hospitalization for COPD was assessed from hospital discharge registries. Using Cox regression, we computed relative risks (RR) and 95% confidence intervals (CI) for mortality endpoints among persons with COPD compared to persons without COPD. Mortality following hip fracture was also compared to age and gender matched controls without hip fracture.

Results: We identified 11,985 persons with first-time hospitalization for hip fracture; 771 (6.4%) had a diagnosis of COPD. Average follow up was 22 months. Compared to persons without COPD, mortality following hip fracture in persons with COPD was RR=1.58 (95% CI 1.30–1.90) at 30 days, RR=1.52 (95% CI 1.30–1.77) at 90-days, RR=1.58 (95% CI 1.40–1.78) at 1 year, and RR=1.71 (95% CI 1.55–1.88) overall. The 1-year mortality in persons with hip fracture and COPD was approximately 3–5 times greater than in controls without hip fracture.

Conclusions: In this cohort, persons with COPD have a 60–70% higher risk of death following hip fracture than those without COPD. In addition, hip fracture and COPD increased 1-year mortality 3–5 times that of persons without hip fracture.

Reproduced with permission from Springer

Aims

This study aimed to understand patient information needs and how best to meet them in order to improve rehabilitation provision and aid disease self-management by exploring experiences of people who had recently completed a pulmonary rehabilitation programme in a community hospital setting.

Methods

Qualitative research using focus groups was undertaken with 23 patients who had completed pulmonary rehabilitation within the previous four months. The focus groups were tape-recorded and contemporaneous notes made. The tapes were transcribed verbatim and template analysis was used to develop themes.

Findings

The key information needs were for a full understanding of the disease to be generated for patients, their families and the wider public much earlier in the disease process and preferably at the point of diagnosis. Patients perceived that they needed to come to terms with the condition. In order to improve disease self-management feelings of anxiety and frustration should be addressed with the suggestion that individual counseling might be made available through the rehabilitation programme. The need for continued support was highlighted with an emphasis on peer group support activities.

Conclusions

The findings have implications for primary care in terms of unmet needs in the early stages of the condition and pulmonary rehabilitation programmes in terms of providing individual counseling and ongoing peer group support to aid disease self-management.

Reproduced with permission from Sage Publications Ltd.