Exacerbations of Chronic Obstructive Pulmonary Disease and Cardiac Events. A Post Hoc Cohort Analysis from the SUMMIT Randomized Clinical Trial.

RATIONALE: Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are common, associated with acute inflammation, and may increase subsequent cardiovascular disease (CVD) risk. OBJECTIVES: Determine whether AECOPD events are associated with increased risk of subsequent CVD. METHODS: We performed a secondary cohort analysis of the SUMMIT (Study to Understand Mortality and Morbidity) trial, a convenience sample of current/former smokers with moderate COPD from 1,368 centers in 43 countries. All had CVD or increased CVD risk. AECOPD was defined as an increase in respiratory symptoms requiring treatment with antibiotics, systemic corticosteroids, and/or hospitalization. CVD events were a composite outcome of cardiovascular death, myocardial infarction, stroke, unstable angina, and transient ischemic attack. All CVD events were adjudicated. Cox proportional hazards models compared the hazard for a CVD event before AECOPD versus after AECOPD. MEASUREMENTS AND MAIN RESULTS: Among 16,485 participants in SUMMIT, 4,704 participants had at least one AECOPD and 688 had at least one CVD event. The hazard ratio (HR) for CVD events after AECOPD was increased, particularly in the first 30 days after AECOPD (HR, 3.8; 95% confidence interval, 2.7-5.5) and was elevated up to 1 year after AECOPD. The 30-day HR after hospitalized AECOPD was more than twofold greater (HR, 9.9; 95% confidence interval, 6.6-14.9). CONCLUSIONS: In patients with COPD with CVD or risk factors for CVD, exacerbations confer an increased risk of subsequent CVD events, especially in hospitalized patients and within the first 30 days after exacerbation. Patients and clinicians should have heightened vigilance for early CVD events after AECOPD. Clinical trial registered with www.clinicaltrials.gov (NCT 01313676).

Simvastatin for the prevention of exacerbations in moderate-to-severe COPD.

BACKGROUND: Retrospective studies have shown that statins decrease the rate and severity of exacerbations, the rate of hospitalization, and mortality in chronic obstructive pulmonary disease (COPD). We prospectively studied the efficacy of simvastatin in preventing exacerbations in a large, multicenter, randomized trial. METHODS: We designed the Prospective Randomized Placebo-Controlled Trial of Simvastatin in the Prevention of COPD Exacerbations (STATCOPE) as a randomized, controlled trial of simvastatin (at a daily dose of 40 mg) versus placebo, with annual exacerbation rates as the primary outcome. Patients were eligible if they were 40 to 80 years of age, had COPD (defined by a forced expiratory volume in 1 second [FEV1] of less than 80% and a ratio of FEV1 to forced vital capacity of less than 70%), and had a smoking history of 10 or more pack-years, were receiving supplemental oxygen or treatment with glucocorticoids or antibiotic agents, or had had an emergency department visit or hospitalization for COPD within the past year. Patients with diabetes or cardiovascular disease and those who were taking statins or who required statins on the basis of Adult Treatment Panel III criteria were excluded. Participants were treated from 12 to 36 months at 45 centers. RESULTS: A total of 885 participants with COPD were enrolled for approximately 641 days; 44% of the patients were women. The patients had a mean (±SD) age of 62.2±8.4 years, an FEV1 that was 41.6±17.7% of the predicted value, and a smoking history of 50.6±27.4 pack-years. At the time of study closeout, the low-density lipoprotein cholesterol levels were lower in the simvastatin-treated patients than in those who received placebo. The mean number of exacerbations per person-year was similar in the simvastatin and placebo groups: 1.36±1.61 exacerbations and 1.39±1.73 exacerbations, respectively (P=0.54). The median number of days to the first exacerbation was also similar: 223 days (95% confidence interval [CI], 195 to 275) and 231 days (95% CI, 193 to 303), respectively (P=0.34). The number of nonfatal serious adverse events per person-year was similar, as well: 0.63 events with simvastatin and 0.62 events with placebo. There were 30 deaths in the placebo group and 28 in the simvastatin group (P=0.89). CONCLUSIONS: Simvastatin at a daily dose of 40 mg did not affect exacerbation rates or the time to a first exacerbation in patients with COPD who were at high risk for exacerbations. (Funded by the National Heart, Lung, and Blood Institute and the Canadian Institutes of Health Research; STATCOPE ClinicalTrials.gov number, NCT01061671.).

Serum bilirubin and the risk of chronic obstructive pulmonary disease exacerbations.

BACKGROUND: Bilirubin is a potent anti-oxidant and higher serum concentrations of bilirubin have been associated with better lung function, slower lung function decline, and lower incidence of chronic obstructive pulmonary disease (COPD). We sought to determine whether elevated bilirubin blood concentrations are associated with lower risk for acute exacerbations of COPD (AECOPD). METHODS: We performed a secondary analyses of data in the Simvastatin for Prevention of Exacerbations in Moderate-to-Severe COPD (STATCOPE) and the Azithromycin for Prevention of Exacerbations of COPD (MACRO) studies. We used time-dependent multivariable Cox proportional hazards analyses, using bilirubin concentrations prior to first AECOPD as the exposure variable and time to first AECOPD as the outcome variable. STATCOPE was used for model development, with validation in MACRO. RESULTS: In STATCOPE (n = 853), higher bilirubin was associated with a lower but statistically insignificant hazard for AECOPD, (adjusted hazard ratio [aHR] 0.89 per log10 increase [95%CI: 0.74 to 1.09; p = 0.26]). In the validation MACRO study (n = 1018), higher bilirubin was associated with a significantly lower hazard for AECOPD (aHR 0.80 per log10 increase [95%CI: 0.67 to 0.94; p = 0.008]). CONCLUSIONS: Bilirubin may be a biomarker of AECOPD risk and may be a novel therapeutic target to reduce AECOPD risk. TRIAL REGISTRATIONS: ClinicalTrials.gov NCT01061671 (registered 02 February 2010) and ClinicalTrials.gov NCT00325897 (registered 12 May 2006).

Azithromycin for prevention of exacerbations of COPD.

BACKGROUND: Acute exacerbations adversely affect patients with chronic obstructive pulmonary disease (COPD). Macrolide antibiotics benefit patients with a variety of inflammatory airway diseases. METHODS: We performed a randomized trial to determine whether azithromycin decreased the frequency of exacerbations in participants with COPD who had an increased risk of exacerbations but no hearing impairment, resting tachycardia, or apparent risk of prolongation of the corrected QT interval. RESULTS: A total of 1577 subjects were screened; 1142 (72%) were randomly assigned to receive azithromycin, at a dose of 250 mg daily (570 participants), or placebo (572 participants) for 1 year in addition to their usual care. The rate of 1-year follow-up was 89% in the azithromycin group and 90% in the placebo group. The median time to the first exacerbation was 266 days (95% confidence interval [CI], 227 to 313) among participants receiving azithromycin, as compared with 174 days (95% CI, 143 to 215) among participants receiving placebo (P<0.001). The frequency of exacerbations was 1.48 exacerbations per patient-year in the azithromycin group, as compared with 1.83 per patient-year in the placebo group (P=0.01), and the hazard ratio for having an acute exacerbation of COPD per patient-year in the azithromycin group was 0.73 (95% CI, 0.63 to 0.84; P<0.001). The scores on the St. George's Respiratory Questionnaire (on a scale of 0 to 100, with lower scores indicating better functioning) improved more in the azithromycin group than in the placebo group (a mean [±SD] decrease of 2.8±12.8 vs. 0.6±11.4, P=0.004); the percentage of participants with more than the minimal clinically important difference of -4 units was 43% in the azithromycin group, as compared with 36% in the placebo group (P=0.03). Hearing decrements were more common in the azithromycin group than in the placebo group (25% vs. 20%, P=0.04). CONCLUSIONS: Among selected subjects with COPD, azithromycin taken daily for 1 year, when added to usual treatment, decreased the frequency of exacerbations and improved quality of life but caused hearing decrements in a small percentage of subjects. Although this intervention could change microbial resistance patterns, the effect of this change is not known. (Funded by the National Institutes of Health; ClinicalTrials.gov number, NCT00325897.).

Vitamin D levels and risk of acute exacerbations of chronic obstructive pulmonary disease: a prospective cohort study.

RATIONALE: Low blood levels of 25-hydroxyvitamin D (25[OH]D) have been associated with a higher risk of respiratory infections in general populations and higher risk of exacerbations of lung disease in people with asthma. We hypothesized that low blood levels of 25(OH)D in patients with chronic obstructive pulmonary disease (COPD) would be associated with an increased risk of acute exacerbations of COPD (AECOPD). OBJECTIVES: To determine if baseline 25(OH)D levels relate to subsequent AECOPD in a cohort of patients at high risk for AECOPD. METHODS: Plasma 25(OH)D was measured at baseline in 973 participants on entry to a 1-year study designed to determine if daily azithromycin decreased the incidence of AECOPD. Relationships between baseline 25(OH)D and AECOPD over 1 year were analyzed with time to first AECOPD as the primary outcome and exacerbation rate as the secondary outcome. MEASUREMENTS AND MAIN RESULTS: In this largely white (85%) sample of North American patients with severe COPD (mean FEV(1) 1.12L; 40% of predicted), mean 25(OH)D was 25.7 ± 12.8 ng/ml. A total of 33.1% of participants were vitamin D insufficient (≥20 ng/ml but <30 ng/ml); 32% were vitamin D deficient (<20 ng/ml); and 8.4% had severe vitamin D deficiency (<10 ng/ml). Baseline 25(OH)D levels had no relationship to time to first AECOPD or AECOPD rates. CONCLUSIONS: In patients with severe COPD, baseline 25(OH)D levels are not predictive of subsequent AECOPD. Clinical trial registered with www.clinicaltrials.gov (NCT00119860).

A comprehensive care management program to prevent chronic obstructive pulmonary disease hospitalizations: a randomized, controlled trial.

BACKGROUND: Improving a patient's ability to self-monitor and manage changes in chronic obstructive pulmonary disease (COPD) symptoms may improve outcomes. OBJECTIVE: To determine the efficacy of a comprehensive care management program (CCMP) in reducing the risk for COPD hospitalization. DESIGN: A randomized, controlled trial comparing CCMP with guideline-based usual care. (ClinicalTrials.gov registration number: NCT00395083) SETTING: 20 Veterans Affairs hospital-based outpatient clinics. PARTICIPANTS: Patients hospitalized for COPD in the past year. INTERVENTION: The CCMP included COPD education during 4 individual sessions and 1 group session, an action plan for identification and treatment of exacerbations, and scheduled proactive telephone calls for case management. Patients in both the intervention and usual care groups received a COPD informational booklet; their primary care providers received a copy of COPD guidelines and were advised to manage their patients according to these guidelines. Patients were randomly assigned, stratifying by site based on random, permuted blocks of variable size. MEASUREMENTS: The primary outcome was time to first COPD hospitalization. Staff blinded to study group performed telephone-based assessment of COPD exacerbations and hospitalizations, and all hospitalizations were blindly adjudicated. Secondary outcomes included non-COPD health care use, all-cause mortality, health-related quality of life, patient satisfaction, disease knowledge, and self-efficacy. RESULTS: Of the eligible patients, 209 were randomly assigned to the intervention group and 217 to the usual care group. Citing serious safety concerns, the data monitoring committee terminated the intervention before the trial's planned completion after 426 (44%) of the planned total of 960 patients were enrolled. Mean follow-up was 250 days. When the study was stopped, the 1-year cumulative incidence of COPD-related hospitalization was 27% in the intervention group and 24% in the usual care group (hazard ratio, 1.13 [95% CI, 0.70 to 1.80]; P= 0.62). There were 28 deaths from all causes in the intervention group versus 10 in the usual care group (hazard ratio, 3.00 [CI, 1.46 to 6.17]; P= 0.003). Cause could be assigned in 27 (71%) deaths. Deaths due to COPD accounted for the largest difference: 10 in the intervention group versus 3 in the usual care group (hazard ratio, 3.60 [CI, 0.99 to 13.08]; P= 0.053). LIMITATIONS: Available data could not fully explain the excess mortality in the intervention group. Ability to assess the quality of the educational sessions provided by the case managers was limited. CONCLUSION: A CCMP in patients with severe COPD had not decreased COPD-related hospitalizations when the trial was stopped prematurely. The CCMP was associated with unanticipated excess mortality, results that differ markedly from similar previous trials. A data monitoring committee should be considered in the design of clinical trials involving behavioral interventions.

Long-term comparative immunogenicity of protein conjugate and free polysaccharide pneumococcal vaccines in chronic obstructive pulmonary disease.

BACKGROUND: Although the 23-valent pneumococcal polysaccharide vaccine (PPSV23) protects against invasive disease in young healthy persons, randomized controlled trials in chronic obstructive pulmonary disease (COPD) have demonstrated no benefit in the intention-to-treat population. We previously reported that the 7-valent diphtheria-conjugated pneumococcal polysaccharide vaccine (PCV7) is safe and induced greater serotype-specific immunoglobulin G (IgG) and functional antibody than did PPSV23 1 month after vaccination. We hypothesized that these advantages would persist at 1 and 2 years. METHODS: One hundred eighty-one patients with moderate to severe COPD were randomized to receive PPSV23 (n = 90) or PCV7 (1.0 mL; n = 91). We measured IgG by enzyme-linked immunosorbent assay and assessed functional antibody activity by a standardized opsonophagocytosis assay, reported as a killing index (OPK). We determined differences in IgG and OPK between vaccine groups at 1 and 2 years. RESULTS: Relative to PPSV23, PCV7 induced greater OPK at both 1 and 2 years for 6 of 7 serotypes (not 19F). This response was statistically greater for 5 of 7 serotypes at 1 year and 4 of 7 at 2 years. Comparable differences in IgG were observed but were less often statistically significant. Despite meeting Centers for Disease Control and Prevention criteria for PPSV23 administration, almost 50% of individuals had never been vaccinated. No differences in the frequency of acute exacerbations, pneumonia, or hospitalization were observed. CONCLUSIONS: PCV7 induces a greater functional antibody response than PPSV23 in patients with COPD that persists for 2 years after vaccination. This superior functional response supports testing of conjugate vaccination in studies examining clinical end points. CLINICAL TRIALS REGISTRATION: NCT00457977.

Influence of lightweight ambulatory oxygen on oxygen use and activity patterns of COPD patients receiving long-term oxygen therapy.

Lightweight ambulatory oxygen devices are provided on the assumptions that they enhance compliance and increase activity, but data to support these assumptions are lacking. We studied 22 patients with severe chronic obstructive pulmonary disease receiving long-term oxygen therapy (14 men, average age = 66.9 y, FEV(1) = 33.6%pred, PaO(2) at rest = 51.7 torr) who were using E-cylinders as their portable oxygen. Subjects were recruited at 5 sites and studied over a 2-week baseline period and for 6 months after randomizing them to either continuing to use 22-lb E-cylinders towed on a cart or to carrying 3.6-lb aluminum cylinders. Utilizing novel electronic devices, ambulatory and stationary oxygen use was monitored continuously over the 2 weeks prior to and the 6 months following randomization. Subjects wore tri-axial accelerometers to monitor physical activity during waking hours for 2-3 weeks prior to, and at 3 and 6 months after, randomization. Seventeen subjects completed the study. At baseline, subjects used 17.2 hours of stationary and 2.5 hours of ambulatory oxygen daily. At 6 months, ambulatory oxygen use was 1.4 ± 1.0 hrs in those randomized to E-cylinders and 1.9 ± 2.4 hrs in those using lightweight oxygen (P = NS). Activity monitoring revealed low activity levels prior to randomization and no significant increase over time in either group. In this group of severe chronic obstructive pulmonary disease patients, providing lightweight ambulatory oxygen did not increase either oxygen use or activity. Future efforts might focus on strategies to encourage oxygen use and enhance activity in this patient group. This trial is registered at ClinicalTrials.gov (NCT003257540).

Disease management program for chronic obstructive pulmonary disease: a randomized controlled trial.

RATIONALE: The effect of disease management for chronic obstructive pulmonary disease (COPD) is not well established. OBJECTIVES: To determine whether a simplified disease management program reduces hospital admissions and emergency department (ED) visits due to COPD. METHODS: We performed a randomized, adjudicator-blinded, controlled, 1-year trial at five Veterans Affairs medical centers of 743 patients with severe COPD and one or more of the following during the previous year: hospital admission or ED visit for COPD, chronic home oxygen use, or course of systemic corticosteroids for COPD. Control group patients received usual care. Intervention group patients received a single 1- to 1.5-hour education session, an action plan for self-treatment of exacerbations, and monthly follow-up calls from a case manager. MEASUREMENTS AND MAIN RESULTS: We determined the combined number of COPD-related hospitalizations and ED visits per patient. Secondary outcomes included hospitalizations and ED visits for all causes, respiratory medication use, mortality, and change in Saint George's Respiratory Questionnaire. After 1 year, the mean cumulative frequency of COPD-related hospitalizations and ED visits was 0.82 per patient in usual care and 0.48 per patient in disease management (difference, 0.34; 95% confidence interval, 0.15-0.52; P < 0.001). Disease management reduced hospitalizations for cardiac or pulmonary conditions other than COPD by 49%, hospitalizations for all causes by 28%, and ED visits for all causes by 27% (P < 0.05 for all). CONCLUSIONS: A relatively simple disease management program reduced hospitalizations and ED visits for COPD. Clinical trial registered with www.clinicaltrials.gov (NCT00126776).

Randomized trial of zileuton for treatment of COPD exacerbations requiring hospitalization.

RATIONALE: Leukotrienes have been implicated in the pathogenesis of acute exacerbations of COPD, but leukotriene modifiers have not been studied as a possible therapy for exacerbations. OBJECTIVE: We sought to test the safety and efficacy of adding oral zileuton (a 5-lipoxygenase inhibitor) to usual treatment for acute exacerbations of COPD requiring hospitalization. METHODS: Randomized double-blind, placebo-controlled, parallel group study of zileuton 600 mg orally, 4 times daily versus placebo for 14 days starting within 12 hours of hospital admission for COPD exacerbation. Primary outcome measure was hospital length of stay; secondary outcomes included treatment failure and biomarkers of leukotriene production. MAIN FINDINGS: Sixty subjects were randomized to zileuton and 59 to placebo (the study was stopped short of enrollment goals because of slow recruitment). There was no difference in hospital length of stay (3.75 +/- 2.19 vs. 3.86 +/- 3.06 days for zileuton vs. placebo, p = 0.39) or treatment failure (23% vs. 27% for zileuton vs. placebo, p = 0.63) despite a decline in urinary LTE(4) levels in the zileuton-treated group as compared to placebo at 24 hours (change in natural log-transformed ng/mg creatinine -1.38 +/- 1.19 vs. 0.14 +/- 1.51, p < 0.0001) and 72 hours (-1.32 +/- 2.08 vs. 0.26 +/- 1.93, p<0.006). Adverse events were similar in both groups. PRINCIPAL CONCLUSIONS: While oral zileuton during COPD exacerbations that require hospital admission is safe and reduces urinary LTE(4) levels, we found no evidence suggesting that this intervention shortened hospital stay, with the limitation that our sample size may have been insufficient to detect a modest but potentially meaningful clinical improvement.

Therapeutic conversion of the combination of ipratropium and albuterol to tiotropium in patients with chronic obstructive pulmonary disease.

BACKGROUND: Ipratropium and albuterol, combined in a single formulation, is widely used as three to four times daily maintenance therapy in COPD. This trial compared tiotropium, once daily, as a potential alternative to patients already taking the ipratropium/albuterol combination. METHODS: 676 patients with moderate to very severe stable COPD (mean FEV(1)=39% of predicted) maintained on ipratropium/albuterol were randomized to receive over an 84 day period either tiotropium (18 mcg) each morning, or continue with ipratropium (26 mcg)/albuterol (206 mcg), 2 actuations 4 times daily, using a parallel group, double-blind, double-dummy design. Six-hour spirometry was assessed on study days 1, 22, and 84, along with safety assessments and other efficacy measures. RESULTS: In terms of primary outcomes, mean trough FEV(1) at 84 days was larger in the tiotropium arm, as compared with the ipratropium/albuterol arm (difference=86 ml; 95% CI, 49 to 123 ml, p<0.0001). The mean FEV(1) AUC(0-6) at 84 days was also larger in the tiotropium arm (difference=17 ml; 95% CI, -21 to 56 ml), this difference being statistically non-inferior to the ipratropium/albuterol arm (p<0.001), but not statistically superior (p=0.37). Other efficacy measures were similar in the two groups. Lower respiratory adverse events were reported in 40 tiotropium patients vs. 52 ipratropium/albuterol patients. Safety reporting was otherwise similar. CONCLUSION: Patients previously maintained on the ipratropium/albuterol combination taken four times daily can be switched to tiotropium once daily with the reasonable expectation of at least equivalent bronchodilation during daytime hours and superior bronchodilation during early morning hours.

Relation of chronic obstructive pulmonary disease exacerbations to FEV(1)--an intricate tango.

This article provides a brief review of the complex interrelationships that surround chronic obstructive pulmonary disease exacerbations and lung function, particularly FEV(1). Areas of discussion include a consideration of baseline lung function as a risk factor for exacerbation, the magnitude and duration of lung function abnormalities after onset and during recovery from exacerbations, the relation between changes in lung function during an exacerbations and clinical outcomes, and the potential impact of recurrent exacerbations on long-term deterioration in lung function.

TORCH and UPLIFT: what has been learned from the COPD "mega-trials"?

TORCH and UPLIFT are amongst the largest and most ambitious COPD trials ever undertaken. In terms of the primary outcomes, both trials were negative. Compared with placebo, combined salmeterol and fluticasone therapy did not significantly reduce all cause mortality over 3 years in TORCH, and tiotropium did not slow the decline in lung function over 4 years in UPLIFT. Secondary outcomes from these studies strongly confirmed findings from previous trials. Monotherapy with all three drugs provided small improvements in respiratory health status and reductions in exacerbation rates with some additive effect from the salmeterol/fluticasone combination. Both salmeterol/fluticasone and tiotropium also reduced COPD hospitalization rates. The trials provide very strong evidence that the long-acting bronchodilators, salmeterol and tiotropium, are not associated with increased risk of death or major cardiovascular adverse events.

Risk indexes for exacerbations and hospitalizations due to COPD.

OBJECTIVE: The ability to predict exacerbations in patients with COPD might permit more rational use of preventive interventions. Our objective was to develop risk indexes for exacerbations and hospitalizations due to exacerbations that might be applied to the individual patient. METHODS: Spirometry, demographics, and medical history were obtained at baseline in 1,829 patients with moderate-to-very severe COPD who entered a trial of inhaled tiotropium. Information about exacerbations and hospitalizations due to exacerbation was collected during the 6-month follow-up period. Analyses of first outcomes were modeled using univariable and multivariable Cox proportional hazards regressions. RESULTS: During follow-up, 551 patients had at least one exacerbation and 151 patients had at least one hospitalization due to exacerbation. In the multivariable model for exacerbation, older age, percentage of predicted FEV(1), duration of COPD, a productive cough, antibiotic or systemic corticosteroid use for COPD in the prior year, hospitalization for COPD in the prior year, and theophylline use at baseline predicted a higher risk. In the multivariable model for hospitalization, older age, percentage of predicted FEV(1), unscheduled clinic/emergency department visits for COPD in the prior year, any cardiovascular comorbidity, and prednisone use at baseline were associated with greater risk. Both the exacerbation and the hospitalization models provided moderately good discrimination, the validated concordance indexes being 0.66 and 0.73, respectively. Methods for calculating risk in individual patients are provided. CONCLUSIONS: Spirometry along with a few questions directed to the patient are strongly predictive of exacerbations and related hospitalizations over the ensuing 6 months.

Management of acute exacerbations of chronic obstructive pulmonary disease in the elderly : an appraisal of published evidence.

Chronic obstructive pulmonary disease (COPD) is a debilitating disease with rising worldwide prevalence. Exacerbations of COPD cause significant morbidity and become more common with advancing age. Healthcare providers caring for elderly patients should therefore be familiar with effective treatments for exacerbations of COPD. An extensive body of literature has identified several effective drug therapies for exacerbations. These drugs include inhaled bronchodilators, systemic corticosteroids and antibacterials. The two main classes of inhaled bronchodilators are beta-adrenoceptor agonists and anticholinergics. These drugs optimise lung function during exacerbations, with neither class demonstrating clear superiority over the other. Systemic corticosteroids are effective when used either for inpatient or outpatient treatment of exacerbations. They hasten recovery from exacerbations and reduce relapse rates. Antibacterials decrease morbidity from exacerbations and may decrease mortality in the more severe exacerbations. Other effective therapies for the treatment of acute exacerbations of COPD include oxygen and non-invasive ventilation. Oxygen can be safely administered in acute exacerbations associated with hypoxaemia, with titration of oxygen delivery to a goal oxygen saturation of 90%. Non-invasive ventilation reduces the morbidity and mortality associated with acute exacerbations complicated by hypercapnic respiratory failure. Strategies to prevent COPD exacerbations include smoking cessation, long-acting inhaled beta-adrenoceptor agonists, inhaled long-acting anticholinergics, inhaled corticosteroids and vaccination. Mucolytic agents, pulmonary rehabilitation, and case management programmes may also reduce exacerbation risk, but the current evidence supporting these interventions is weaker.

Prevention of exacerbations of chronic obstructive pulmonary disease with tiotropium, a once-daily inhaled anticholinergic bronchodilator: a randomized trial.

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) frequently develop exacerbations, leading to major clinical and health resource use ramifications. OBJECTIVE: To prospectively evaluate the effectiveness of a long-acting inhaled anticholinergic bronchodilator, tiotropium, in reducing COPD exacerbations and exacerbation-related health care utilization. DESIGN: Randomized, double-blind study. SETTING: 26 Veterans Affairs medical centers. PATIENTS: 1829 patients with moderate to severe COPD (mean baseline FEV(1), 36% predicted). INTERVENTION: Once-daily tiotropium (18 microg) or placebo for 6 months. Patients otherwise received usual care, except for other anticholinergic bronchodilators. MEASUREMENTS: The coprimary end points were the percentage of patients with a COPD exacerbation and the percentage of patients with a COPD-related hospitalization. RESULTS: Tiotropium significantly reduced the percentage of patients experiencing 1 or more exacerbations compared with placebo (27.9% vs. 32.3%, respectively; difference, -5.7 percentage points [95% CI, -10.4 to -1.0 percentage points]; P = 0.037). Fewer tiotropium patients were hospitalized because of COPD exacerbation (7.0% vs. 9.5%, respectively; difference, -3.0 percentage points [CI, -5.9 to -0.1 percentage points]; P = 0.056), although this difference was of borderline statistical significance. Analysis of secondary outcomes indicates that tiotropium may lengthen the time to first COPD exacerbation (P = 0.028) and reduce health care utilization for exacerbations, including the frequency of hospitalizations (P = 0.047), unscheduled clinic visits (P = 0.019), and days of antibiotic treatment (P = 0.015). Tiotropium did not statistically significantly reduce all-cause hospitalization rates. LIMITATIONS: Trial participants were enrolled from 1 health care system, and 99% were men. The follow-up period extended for only 6 months. CONCLUSIONS: Tiotropium reduces COPD exacerbations and may reduce related health care utilization in patients with moderate to severe COPD.

High-dose oral N-acetylcysteine fails to improve respiratory health status in patients with chronic obstructive pulmonary disease and chronic bronchitis: a randomized, placebo-controlled trial.

BACKGROUND: Clinical outcomes are worse in patients with COPD and chronic bronchitis. N-acetylcysteine (NAC) is commonly prescribed for such patients but with uncertain clinical benefits. We postulated that oral NAC, at much larger doses than those ordinarily prescribed, would improve clinical outcomes in a subset of patients with COPD and chronic bronchitis. OBJECTIVE: The aim of this study was to determine whether very high-dose NAC would improve respiratory health status in patients with COPD and chronic bronchitis. METHODS: Patients with COPD and chronic bronchitis were enrolled in a randomized, controlled, double-blinded trial. Patients received oral NAC (1,800 mg) or matching placebo twice daily for 8 weeks in addition to their usual respiratory medications. The primary outcome, respiratory health status, was assessed by changes in the St George's Respiratory Questionnaire. The effects of NAC on lung function and circulating markers of oxidative stress and inflammation were also evaluated. RESULTS: We terminated the study prematurely because new external information suggested the possibility of a safety issue. Of the planned 130 patients, 51 were randomized and 45 (22 in the placebo arm and 23 in the NAC arm) completed the study. There was no statistically significant difference between changes in the St George's Respiratory Questionnaire total score, comparing NAC to placebo (adjusted mean difference, 0.1 U; 95% CI, -7.8 to 8.18 U; P=0.97). There were also no significant NAC-related improvements in any of the secondary outcomes. CONCLUSION: In this 8-week trial, we were unable to show any clinical benefit from a very high dose of NAC in patients with COPD and chronic bronchitis.