Short-Term Oxygen Therapy Outcomes in COPD.

Rationale: Short-term oxygen therapy (STOT) is often prescribed to allow patients with chronic obstructive pulmonary disease (COPD) to be discharged safely from hospital following an acute illness. This practice is widely accepted without being based on evidence. Purpose: Our objective was to describe the characteristics and outcomes of patients with COPD who received STOT. Patients and Methods: The study was a secondary analysis of the INOX trial, a 4-year randomised trial of nocturnal oxygen in COPD. The trial indicated that nocturnal oxygen has no significant effect on survival or progression to LTOT, allowing our merging of patients who received nocturnal oxygen and those who received placebo into a single cohort to study the predictors and outcomes of STOT regardless of the treatment received during the trial. Results: Among the 243 participants in the trial, 60 required STOT on at least one occasion during follow-up. Patients requiring STOT had more severe dyspnoea and lung function impairment, and lower PaO2 at baseline than those who did not. STOT was associated with subsequent LTOT requirement (hazard ratio [HR]: 4.59; 95% confidence interval [CI]: 2.98-7.07) and mortality (HR: 1.93; 95% CI: 1.15-3.24). The association between STOT and mortality was confounded by age, disease severity and comorbidities. Periods of STOT of more than one month and/or repeated prescriptions of STOT increased the probability of progression to LTOT (OR: 5.07; 95% CI: 1.48-18.8). Conclusion: Following an acute respiratory illness in COPD, persistent hypoxaemia requiring STOT is a marker of disease progression towards the requirement for LTOT.

Evaluating nocturnal oxygen desaturation in COPD--revised.

BACKGROUND: Although in patients with COPD, the approach to daytime hypoxemia using long-term oxygen therapy (LTOT) is established, the best approach to transient nocturnal desaturation varies among clinicians. An understanding of the prevalence of nocturnal desaturation in COPD, in the absence of other respiratory co-morbidities, is an important step towards its standardized management. METHODS: We conducted a 5 site cross-sectional study of stable patients with COPD and mild-to-moderate daytime hypoxemia (PaO(2) 56-69 mmHg). Nocturnal saturation was monitored using home oximetry on 2 occasions over a 2-week period. Patients were classified in 3 categories: (A) no significant nocturnal desaturation; (B) significant nocturnal desaturation without evidence of sleep apnea; (C) significant nocturnal desaturation with evidence of sleep apnea. RESULTS: In 128 patients (mean FEV(1): 37% predicted), we noted an excellent test-retest reliability between the 2 oximetries. Forty-nine patients (38%) were classified as nocturnal desaturators without evidence of sleep apnea, and 20 patients (16%) were classified as desaturators with evidence of sleep apnea. Nocturnal desaturation without sleep apnea could not be predicted by any patient characteristic or physiological measure. CONCLUSIONS: A significant proportion (38%) of patients with moderate-to-severe COPD who do not qualify for home oxygen therapy based on their daytime PaO(2) have nocturnal oxygen desaturation without evidence of sleep apnea. Home oximetry is an effective practical method for screening this population.

Effects of home-based pulmonary rehabilitation in patients with chronic obstructive pulmonary disease: a randomized trial.

BACKGROUND: Home-based rehabilitation is a promising approach to improve access to pulmonary rehabilitation. OBJECTIVE: To assess whether self-monitored, home-based rehabilitation is as effective as outpatient, hospital-based rehabilitation in patients with chronic obstructive pulmonary disease (COPD). DESIGN: Randomized, multicenter, noninferiority trial. SETTING: 10 academic and community medical centers in Canada. PATIENTS: 252 patients with moderate to severe COPD. INTERVENTION: After a 4-week education program, patients took part in home-based rehabilitation or outpatient, hospital-based rehabilitation for 8 weeks. They were followed for 40 weeks to complete the 1-year study. MEASUREMENTS: The primary outcome was the change in Chronic Respiratory Questionnaire dyspnea subscale score at 1 year. The primary analysis took a modified intention-to-treat approach by using all patients who provided data at the specified follow-up time, regardless of their level of adherence. The analysis used regression modeling that adjusted for the effects of center, sex, and baseline level. All differences were computed as home intervention minus outpatient intervention. RESULTS: Both interventions produced similar improvements in the Chronic Respiratory Questionnaire dyspnea subscale at 1 year: improvement in dyspnea of 0.62 (95% CI, 0.43 to 0.80) units in the home intervention (n = 107) and 0.46 (CI, 0.28 to 0.64) units in the outpatient intervention (n = 109). The difference between the 2 treatments at 1 year was small and clinically unimportant. The 95% CI of the difference did not exceed the prespecified noninferiority margin of 0.5: difference in dyspnea score of 0.16 (CI, -0.08 to 0.40). Most adverse events were related to COPD exacerbations. No serious adverse event was considered to be related to the study intervention. LIMITATION: The contribution of the educational program to the improvement in health status and exercise tolerance cannot be ascertained. CONCLUSION: Home rehabilitation is a useful, equivalent alternative to outpatient rehabilitation in patients with COPD.

A Canadian, multicentre, randomized clinical trial of home-based pulmonary rehabilitation in chronic obstructive pulmonary disease: rationale and methods.

BACKGROUND: Pulmonary rehabilitation remains largely underused. Self-monitored, home-based rehabilitation is a promising approach to improving the availability of pulmonary rehabilitation. OBJECTIVE: To report the rationale and methods of a trial comparing the effectiveness of self-monitored, home-based rehabilitation with hospital-based, outpatient rehabilitation in patients with chronic obstructive pulmonary disease (COPD). STUDY DESIGN: A parallel-group, randomized, noninferiority, multicentre trial will be performed with 240 patients with moderate to severe COPD. INTERVENTION: Patients will be randomly assigned to conventional, supervised, hospital-based outpatient rehabilitation or self-monitored, home-based rehabilitation. Both interventions will include a standardized, comprehensive self-management program, in addition to the hospital-based outpatient or home-based exercise program. After the three-month intervention, patients in both groups will be encouraged to continue exercising at home. Patients will be assessed monthly with telephone interviews and in person at enrollment, three months and 12 months. OUTCOMES: The dyspnea domain of the Chronic Respiratory Questionnaire (CRQ) at 12 months is the primary outcome variable. Secondary outcome variables include total and domain-specific CRQ scores; exercise tolerance and activity of daily living; health service use over the one-year study period; and direct and indirect costs of COPD treatment. ANALYSIS: An intent-to-treat approach will be used as the primary analysis. The primary analysis will focus on the change in the CRQ dyspnea score using a two-sided t distribution based on 95% CIs. The same approach will be used for secondary continuous outcome variables. CONCLUSION: The present trial will address two unresolved issues in pulmonary rehabilitation for patients with COPD: the short-term and long-term effectiveness of home-based pulmonary rehabilitation strategies. The authors will also determine if home-based pulmonary rehabilitation can reduce health service use (eg, hospitalizations and emergency visits) and if it can be done at a lower cost than the traditional hospital-based outpatient pulmonary rehabilitation.