Functional status and survival in COPD.

A limitation in functional status is an important factor in the handicap caused by advanced chronic lung disease such as COPD. Indicators of functional status in these patients include exercise performance levels common to everyday activity (such as the six minute walk distance) and scores on self-completed questionnaires rating interference with daily activities (such as the Functional Activities component of the PFSS). Both a longer timed walk distance and a higher functional performance score were highly predictive of survival in independent studies of pulmonary rehabilitation patients. This probably reflects the ability of measures of functional status to quantify non-pulmonary as well as morbidity, both of which contribute to the overall mortality in individuals with advanced lung disease.

A long-term evaluation of once-daily inhaled tiotropium in chronic obstructive pulmonary disease.

Currently available inhaled bronchodilators used as therapy for chronic obstructive pulmonary disease (COPD) necessitate multiple daily dosing. The present study evaluates the long-term safety and efficacy of tiotropium, a new once-daily anticholinergic in COPD. Patients with stable COPD (age 65.2+/-8.7 yrs (mean+/-SD), n=921) were enrolled in two identical randomized double-blind placebo-controlled 1-yr studies. Patients inhaled tiotropium 18 microg or placebo (mean screening forced expiratory volume in one second (FEV1) 1.01 versus 0.99 L, 39.1 and 38.1% of the predicted value) once daily as a dry powder. The primary spirometric outcome was trough FEV1 (i.e. FEV1 prior to dosing). Changes in dyspnoea were measured using the Transition Dyspnea Index, and health status with the disease-specific St. George's Respiratory Questionnaire and the generic Short Form 36. Medication use and adverse events were recorded. Tiotropium provided significantly superior bronchodilation relative to placebo for trough FEV1 response (approximately 12% over baseline) (p<0.01) and mean response during the 3 h following dosing (approximately 22% over baseline) (p<0.001) over the 12-month period. Tiotropium recipients showed less dyspnoea (p<0.001), superior health status scores, and fewer COPD exacerbations and hospitalizations (p<0.05). Adverse events were comparable with placebo, except for dry mouth incidence (tiotropium 16.0% versus placebo 2.7%, p<0.05). Tiotropium is an effective, once-daily bronchodilator that reduces dyspnoea and chronic obstructive pulmonary disease exacerbation frequency and improves health status. This suggests that tiotropium will make an important contribution to chronic obstructive pulmonary disease therapy.

Salmeterol plus theophylline combination therapy in the treatment of COPD.

BACKGROUND: Patients with COPD often require multiple therapies to improve lung function and decrease symptoms and exacerbations. Salmeterol and theophylline are indicated for the treatment of COPD, but the use of these agents in combination has not been extensively studied. OBJECTIVES: To compare the efficacy and safety of salmeterol plus theophylline vs either agent alone in COPD. METHODS: Randomized, double-blind, double-dummy, parallel-group trial in 943 patients with COPD. After an open-label theophylline titration period (serum levels, 10 to 20 microg/mL), patients were randomly assigned to receive salmeterol (42 microg bid) plus theophylline, salmeterol (42 microg bid), or theophylline for 12 weeks. Serial pulmonary function tests were completed on day 1 and treatment week 12. Patients kept diary cards and noted their peak flow rates, symptom scores, and albuterol use, and periodically completed quality-of-life and dyspnea questionnaires. RESULTS: All three groups significantly improved compared with baseline. Combination treatment with salmeterol plus theophylline provided significantly (p < or = 0.045) greater improvements in pulmonary function; significantly (p < or = 0.048) greater decreases in symptoms, dyspnea, and albuterol use; and significantly fewer COPD exacerbations (p = 0.023 vs theophylline). In general, treatment with salmeterol provided greater improvement in lung function and satisfaction with treatment compared with theophylline. Salmeterol treatment was also associated with significantly fewer drug-related adverse events (p < or = 0.042) than either treatment that included theophylline. The safety profile (adverse events, vital signs, and ECG findings) of the two treatments that included theophylline were similar. CONCLUSION: Patients with COPD may benefit from combination treatment with salmeterol plus theophylline, without a resulting increase in adverse events or other adverse sequelae.

Functional status and survival following pulmonary rehabilitation.

BACKGROUND: Functional exercise capacity has been shown to be a strong predictor of survival following pulmonary rehabilitation. This study evaluated whether questionnaire-rated functional status is also predictive of survival. PATIENTS AND METHODS: Following pulmonary rehabilitation, patients with advanced chronic lung disease were evaluated for survival, 6-min walk distance, and questionnaire-rated functional status. The latter was measured using the pulmonary functional status scale, which has subscores of functional activities, psychological status, and dyspnea. Information on survival was available on 149 patients. RESULTS: The mean age was 69 years, and 45% of patients were male. Eighty-nine percent had a diagnosis of COPD, and their FEV(1) was 37+/-18% of predicted. Ninety-one (61%) were married. The 3-year survival for the group was 85%. Age, gender, body mass index, and primary diagnosis were not related to survival. Variables strongly associated with increased survival following pulmonary rehabilitation included a higher postrehabilitation Functional Activities score, a longer postrehabilitation 6-min walk distance, and being married (vs widowed, single, or divorced). Disease severity variables associated with survival included an initial referral to outpatient pulmonary rehabilitation, no supplemental oxygen requirement, and a higher percent-predicted FEV(1). CONCLUSION: Indicators of functional status are strong predictors of survival in patients with advanced lung disease.

Long-term benefits of short-stay inpatient pulmonary rehabilitation in severe chronic obstructive pulmonary disease.

The beneficial effects of pulmonary rehabilitation programmes on the overall quality of life in patients with chronic obstructive pulmonary disease (COPD) has been well documented. However, there has been a paucity of studies demonstrating the long-term benefits of short-stay inpatient pulmonary rehabilitation (SSIPR) programmes in patients with severe COPD (forced expiratory volume in one second (FEV1) < 40% of predicted). The authors have previously reported that their multidisciplinary SSIPR programme improved outcome measurements immediately post-rehabilitation in 38 patients with severe COPD. The purpose of this study was to evaluate the long-term (1-yr follow-up) benefits of SSIPR in these patients. The outcome measurements used were: timed 12-min walking distance, Borg dyspnoea scale, annual days of acute care hospitalization, and Pulmonary Functional Status Scale. All outcome measurements were significantly improved at 1 yr post-SSIPR as compared to pre-SSIPR values. The 12-min walking distance was significantly improved in patients 1 yr post-SSIPR (251 m) as compared to either pre-SSIPR (133 m, p < 0.0001) or immediately post-SSIPR (224 m, p < 0.01). The number of annual days of acute care hospitalization was reduced from 15.4 pre-SSIPR to 3.8 (p < 0.0001) 1 yr post-SSIPR. The Borg dyspnoea scale measurement showed improvement, both at rest and after 12 min walking at 1 yr post-SSIPR. Also, the Pulmonary Functional Status Scale analysis showed significant (p < 0.001) sustained improvement at 1 yr post-SSIPR as compared to pre-SSIPR. In conclusion, it has been demonstrated that long-term sustained outcome benefits can be achieved from a comprehensive short-stay inpatient pulmonary rehabilitation programme for patients with severe chronic obstructive pulmonary disease.

The influence of demographic and socioeconomic factors on health-related quality of life in asthma.

BACKGROUND: Although health-related quality of life (HRQL) in asthma is strongly influenced by disease severity, demographic and socioeconomic variables may also be important factors. OBJECTIVE: We related demographics, asthma severity, and socioeconomic factors to HRQL. METHODS: We interviewed 50 patients with moderate or severe asthma recruited from outpatient health center-based clinics to determine demographics, socioeconomic status, asthma severity, medication use, and HRQL. For HRQL, the mean total score of the Asthma Quality of Life Questionnaire (AQLQ) and the Medical Outcomes Study Short-Form 36 questionnaires physical and mental component summary scores (PCS and MCS, respectively) were used. RESULTS: The mean patient age was 46 +/- 14 years, and the FEV1 was 75% +/- 21% of predicted value. Twenty-nine subjects had been hospitalized for asthma, 29 belonged to a minority racial/ethnic group, and 16 had less than 12 years of education. The mean total AQLQ score was 4.12 +/- 1.42, the PCS was 37 +/- 10, and the MCS was 45 +/- 13. In univariate analyses, severity (nighttime awakenings, prednisone use, and a history of emergency department visits), racial/ethnic group (African American, white, or Hispanic), and socioeconomic status (low educational level, unemployed, family income under $20,000, public assistance, or no health insurance) were related to HRQL. These factors explained 67% of the variance of AQLQ and 48% of the variance of the PCS. Much of the quality of life variance was shared among these variables. Explanatory variables were not related to MCS in multivariate analysis. CONCLUSION: Socioeconomic status is an additional important independent factor influencing HRQL in asthma. In this study it was difficult to separate out the unique effects of socioeconomic status and race/ethnicity.

Adherence with twice-daily dosing of inhaled steroids. Socioeconomic and health-belief differences.

Poor adherence to medication regimens may be contributing to the recent increase in asthma morbidity and mortality. We examined patient characteristics that may influence adherence to twice-daily inhaled steroid regimens. Fifty adults with moderate to severe asthma completed questionnaires examining sociodemographics, asthma severity, and health locus of control. Adherence was electronically monitored for 42 d. Following monitoring, patients' understanding of asthma pathophysiology and the function of inhaled corticosteroids were assessed. Patient beliefs about the effectiveness and convenience of these medications, and their perception of communications with their clinician were measured. Mean adherence was 63% +/- 38%; 54% of subjects recorded at least 70% of the prescribed number of inhaled-steroid actuations. Factors associated with poor adherence were less than 12 yr of formal education (p < 0. 001), poor patient-clinician communication (p < 0.001), household income less than $20,000 (p = 0.002), Spanish as primary language (p = 0.005), and minority status (p = 0.007). In a multiple logistic regression analysis, less than 12 yr of formal education (OR: 6.72; CI: 1.10 to 41.0) and poor patient-clinician communication (OR: 1.2; CI: 1.01 to 1.55) were independently associated with poor adherence. These results emphasize the importance of socioeconomic status and adequate patient-clinician communication for adherence to inhaled-steroid schedules.

COPD and other diseases in chronically ventilated patients in a prolonged respiratory care unit: a retrospective 20-year survival study.

OBJECTIVES: To evaluate the long-term prognosis of ventilator-dependent patients. DESIGN: Retrospective study. SETTING: A prolonged respiratory care unit (PRCU). The PRCU provides comprehensive medical, nursing, and respiratory care to tracheostomized, ventilator-dependent adult patients who had failed all attempts at weaning. Because of their medical complexity, these patients could not be discharged to a lower level of care. PATIENTS: Of the 293 patients admitted to the PRCU over a 20-year period beginning January 1, 1977, 145 had respiratory failure from COPD, 22 from spinal cord disease or trauma, 34 from primary CNS disease, 50 from primary neuromuscular disease, and 16 from chest wall disease. Twenty-six patients were not classifiable into the above categories. MEASUREMENTS: Demographics, diagnoses, and survival data were reviewed. The survival of patients with COPD was compared with the other diagnosis categories using the Cox proportional hazards model. RESULTS: The median survival for the entire group was 9 months; younger age and female gender were both predictive of longer survival (both, p < 0.001). The median survival of those with COPD (5 months) was significantly shorter than that of patients with spinal cord disease (47 months), neuromuscular disease (17 months), and chest wall disease (27 months) (all, p < 0.01). These differences in survival were present even with inclusion of gender and age in the model as covariates. The survival of patients with CNS disease was not significantly different from survival of patients with COPD. CONCLUSION: Chronically ventilated patients with respiratory failure from COPD have a significantly worse prognosis than patients with respiratory failure from other causes.

Demographic predictors of asthma treatment site: outpatient, inpatient, or emergency department.

OBJECTIVE: To identify the demographic predictors of asthma treatment site: outpatient clinic, emergency department, or hospital. METHODS: From the November 1993 to July 1995 claims data of the University of Connecticut Health Center, asthmatic patient sex, age, racial/ethnic group, address, and health insurance status were examined to identify predictors of treatment site. Patient addresses generated maps and census data. RESULTS: 3288 visits were made by 1455 patients; 8%, 34%, and 58% came from poverty level, low, and higher income residential areas, respectively. Insurance type and then age were the most significant predictors of treatment site. Adults having commercial insurance or Medicare were most likely treated as outpatients, self-pay patients 5 times more likely in the emergency department, and those receiving public assistance 2.4 times more likely in the hospital. Only 9% of Medicaid children and 22% with commercial insurance were evaluated as outpatients. Neither sex nor race/ethnicity was an important predictor of treatment site. CONCLUSION: Although not population-based, this group of asthmatic patients represents a group diverse in socioeconomic status and racial/ethnic background. Insurance category was the most influential factor predicting asthma treatment site, suggesting that economic status may be the most important determinant of higher morbidity. Children were treated predominantly in acute care settings.

Perception of airway obstruction in asthma: sequential daily analyses of symptoms, peak expiratory flow rate, and mood.

BACKGROUND AND OBJECTIVE: Studies have demonstrated a weak correlation between the degree of airways obstruction and the severity of asthma symptoms. Although the causes for this disparity are probably multiple, mood has been hypothesized to modulate symptoms. This investigation was designed to evaluate the effect of mood and other patient characteristics on the perception of airways obstruction. METHODS: We compared mood variables, symptom severity, albuterol use, and peak expiratory flow rate (PEFR) measured three times daily over a 21-day period in 21 adults with moderate to severe asthma. Electronic equipment was used for data collection. Analyses included both individual patient assessments and a within-subjects, time series, pooled regression of concurrent and time-lag data. RESULTS: After pooling 1323 observations, there was a weak concurrent relationship between symptoms and PEFR (beta = -0.17, p < 0.001). Only five patients (24%) were accurate perceivers, defined by a statistically significant relationship between symptoms and PEFR across time. Higher forced expiratory flow at 25% to 75% of capacity predicted perception accuracy (p = 0.004); active mood was marginally associated with accuracy (p = 0.06). These two variables together explained 41% of the variation in perception accuracy (p = 0.004). Mood did not independently predict symptoms, but conversely, increased symptoms predicted less pleasant mood (beta = 0.08, p < 0.001), less active mood (beta = -0.11, p < 0.001), and less active-pleasant mood (beta = 0.06, p < 0.001). PEFR did not predict mood, and only pleasant mood independently predicted higher PEFR (beta = 0.04, p < 0.05). Symptoms, but not PEFR, were concurrently associated with albuterol use (beta = 0.24, p < 0.001). CONCLUSION: The relationship between changes in PEFR and symptoms over time was generally poor. Those patients with lower FEF25-75 values tended to be less accurate perceivers. Mood states were influenced by asthma symptoms, but the converse was not true.

The effectiveness of once-daily dosing of inhaled flunisolide in maintaining asthma control.

OBJECTIVE: The purpose of this study was to evaluate the feasibility of switching to once-daily (qd) administration of flunisolide in patients with asthma that was controlled by twice-daily (bid) dosing of this inhaled steroid. METHODS: Three hundred sixty-six adults and children with bronchial asthma that was controlled with inhaled steroids were recruited for this prospective, double-blind, parallel-group study. After a 4-week, stable baseline period of flunisolide administration, 2 inhalations (500 microg) twice daily, each patient was randomized into one of four 12-week flunisolide treatment groups: group 1, 2 inhalations (500 microg) bid; group 2, 4 inhalations (1000 microg) qd in the morning; group 3, 4 inhalations (1000 microg) qd in the evening; or group 4, 2 inhalations (500 microg) qd in the morning. Outcome measures included morning and evening asthma symptoms (scale of 0 to 3), daytime and nighttime albuterol use, morning and evening peak expiratory flow rate (PEFR), FEV1, and methacholine PC20. In addition, a subset of patients in each group had 24-hour urinary cortisol levels measured before and after randomization. RESULTS: Outcome measures in the four groups were not significantly different at baseline before randomization. The three groups that received maintenance therapy with flunisolide, 1000 microg daily, did not show significant changes from baseline values and remained comparable in all outcome areas. Asthma control in the group randomized to flunisolide 500 microg qd, however, deteriorated significantly: morning symptoms increased by 0.21 units (48%), evening symptoms increased by 0.15 units (31%), daytime albuterol use increased by 0.42 inhalations per day (37%), nighttime albuterol use increased by 0.48 inhalations per night (91%), morning PEFR decreased by 17.1 L/min (4%), and evening PEFR decreased by 12.6 L/min (3%). There were no significant changes in PC20 or 24-hour urinary cortisol levels in any group. CONCLUSIONS: For patients with asthma that was stabilized by 2 inhalations of flunisolide (500 microg) bid, switching to 4 inhalations (1000 microg) qd in either the morning or evening is effective in maintaining asthma control. Reducing the dose to 2 inhalations (500 microg) qd in the morning, however, leads to a deterioration in asthma control.

The effect of inhaled albuterol in moderate to severe asthma.

BACKGROUND: Some recent clinical investigations suggest that regular use of inhaled bronchodilators may lead to deterioration in asthma control. OBJECTIVE: The purpose of this study was to evaluate the effect of albuterol dosing schedule on clinical outcome in subjects with moderate to severe stable asthma. METHODS: Seventeen adults were randomized to two 15-week treatment periods in a double-blind crossover design. Throughout the study, subjects were instructed to take two inhalations four times daily from an unlabeled "test" canister. In the four times daily and as-needed (QID + PRN) period, this canister contained albuterol; in the as-needed (PRN) period, it contained placebo. A "rescue" albuterol canister was available for as-needed use at all times. Inhaler actuations from both the test and rescue canisters were electronically recorded. Outcome measures included prednisone requirements, morning and evening symptoms and peak expiratory flow rates, total and nighttime rescue albuterol use, and asthma-specific quality of life. RESULTS: The two treatment periods did not differ in symptoms, nighttime albuterol use, or asthma quality of life. During the QID+PRN period both morning and evening peak expiratory flow rates were significantly higher (p < 0.01 and 0.001, respectively) and total rescue use of albuterol was significantly less (p < 0.05) than the PRN period. Days on prednisone tended to be lower in the regular dosing period (p = 0.08). CONCLUSION: In our sample of patients with moderate to severe asthma, four times daily dosing of albuterol did not lead to deterioration of asthma control.

Variables related to increased mortality following out-patient pulmonary rehabilitation.

Although patients with advanced pulmonary diseases have significant improvement in exercise ability and functional status following comprehensive out-patient pulmonary rehabilitation (OPR), their long-term prognosis once they have reached this stage of their diseases remains poor. To further evaluate predictors of increased mortality in these patients, we related patient characteristics and short-term outcome obtained during OPR assessment of 158 patients to subsequent survival. The time period from OPR to death or collection of survival data was 40.0 +/- 17.1 months. The following variables were tested individually and in stepwise fashion using a proportional hazards model: 1) age; 2) gender; 3) pulmonary diagnosis; 4) prebronchodilator forced expiratory volume in one second (FEV1); 5) arterial oxygen tension (Pa,O2) and arterial carbon dioxide tension (Pa,CO2); 6) body mass index (BMI); 7) pre- and post-OPR 12 min walking distance (12-MW); 8) pre- and post-OPR quality of life, using the Chronic Respiratory Disease Questionnaire (CRDQ); 9) number and type of nonpulmonary diagnoses; and 10) number of medications. Separate survival analyses were performed for all deaths (the total group), respiratory deaths only (nonrespiratory deaths excluded), and nonrespiratory deaths only (respiratory deaths excluded). Forty three patients (27%) died during the study period; and the 3 year survival was 80%. For all three survival analyses, the post-OPR 12-MW was the most significant variable related to prognosis: patients with low timed walking distance had increased mortality both from respiratory and nonrespiratory causes. Other variables related to increased mortality included: elevated Pa,CO2; low pre-OPR 12-MW; reduced Pa,O2; low FEV1; low BMI, increased number of medications, and increased CRDQ dyspnoea. These results indicate that the timed walking distance following out-patient pulmonary rehabilitation is an important predictor of survival in patients with advanced pulmonary disease.

Addition of anticholinergic solution prolongs bronchodilator effect of beta 2 agonists in patients with chronic obstructive pulmonary disease.

A randomized, double-blind placebo-controlled clinical trial was designed to assess the safety, efficacy, and duration of the bronchodilation resulting from the addition of 500 micrograms of ipratropium bromide (Atrovent; Boehringer Ingelheim, CT) inhalation solution to standard small volume nebulizer treatments with 2.5 mg albuterol inhalation solution. A total of 195 patients (63% men, average age 64 years) with > 10 pack-year smoking histories and stable, moderate-to- severe chronic obstructive pulmonary disease (COPD; forced expiratory volume in 1 second [FEV1] 1.02 liter, 38.8% predicted) from eight university-affiliated chest clinics in seven U.S. cities were enrolled into the study. Asthma, rhinitis, and eosinophilia were exclusions, as was daily use of > 10 mg of prednisone (or 20 mg on alternate days). There was a 2-week stabilization period during which the patients were instructed in the use of the small volume nebulizers, which they used three times daily with albuterol alone. They were asked to keep daily logs of peak flow rates, pulmonary symptoms, and additional medication usage. On their test day 1 the subjects came to the pulmonary function laboratory having been off theophylline for 24 hours and beta 2-agonists for 12 hours and performed a baseline spirometry. They then received their morning small volume nebulizer treatment of albuterol to which was added either 500 micrograms if ipratropium bromide or a saline placebo. Spirometry was repeated at 15, 30, and 60 minutes, and then hourly for 8 hours. Subjects then took home a 2-week supply of albuterol and test drug for thrice daily use in their small volume nebulizer. They were evaluated for pulmonary symptoms and adverse effects every 14 days. The 8-hour spirometry was repeated on test day 43 and finally on test day 85. Primary data evaluated were the peak increase in FEV1 and the area between the FEV1 baseline value and the 8-hour FEV1 curve. Similar calculations were made for forced vital capacity (FVC) and 25-75% forced expiratory flow (FEF25-75%). On test day 1 the peak increase in FEV1 for the ipratropium bromide + albuterol subjects was 26% greater than those on placebo + albuterol (p < 0.003). The area under the 8-hour FEV1 curve was 64% greater in those given ipratropium bromide on test day 1 (p < 0.0002). Similar increases were seen in FVC and FEF25-75%. The peak improvements in FEV1 and FVC with the addition of ipratropium bromide to albuterol were maintained on test days 43 and 85. Considering the safety and efficacy profiles of this combination, the data would suggest that ipratropium bromide inhalation solution should be considered first-line therapy for those patients with COPD requiring small volume nebulizer treatments.

A comparison of outpatient cardiac and pulmonary rehabilitation patients.

PURPOSE: Although cardiac and pulmonary rehabilitation are frequently considered together, differences in the two populations have not been evaluated adequately. METHODS: This study compared patients who were referred to outpatient cardiac and pulmonary rehabilitation over a 1-year period at the authors' institution. Fifty-five cardiac rehabilitation patients (CR) and 47 pulmonary rehabilitation patients (PR) were studied with respect to age, gender, weight, smoking history, functional status, employment status, numbers and types of diagnoses and medications, and number of recent hospitalizations and hospital days. RESULTS: Cardiac rehabilitation patients were approximately 7 years younger, smoked less, were somewhat heavier, had a markedly better functional status, and were more likely employed than their counterparts in pulmonary rehabilitation. In addition, this group had fewer diagnoses and used fewer medications than PR patients. The number of hospitalizations and hospital days in the year preceding rehabilitation, however, were greater in CR patients than in PR patients. CONCLUSIONS: CR patients and PR patients are quite distinct with respect to demographics, functional status, comorbidity, and hospital resource consumption.

Common measures of asthma severity lack association for describing its clinical course.

BACKGROUND AND OBJECTIVE: To address the problems of increasing asthma morbidity and mortality rates, reliable severity measures must be identified. Accordingly, we compared three measures and their relationship to beclomethasone compliance. METHODS: Three clinical measures (symptom scores, morning peak expiratory flow rates, and number of as needed albuterol inhalations with Nebulizer Chronologs [Forefront Technologies, Inc., Lakewood, Colo.]) were assessed daily in 13 adults with asthma for 8.9 +/- 2.1 weeks. The relationships among these three variables were analyzed in terms of Pearson correlation coefficients. These were evaluated for each of the three possible pairs of the three clinical measures for each of the 13 patients. The relationship between inhaled beclomethasone compliance and the pairwise correlations was studied with the use of nonparametric statistical procedures. RESULTS: In four of the 13 patients, no pairwise correlations between any of the three severity measures were observed. The peak expiratory flow rate-symptom score relationship was observed in eight patients, whereas peak expiratory flow rate-albuterol use and albuterol use-symptom score correlations were each seen in four patients. Mean beclomethasone compliance was 64% and was greatest in those patients whose albuterol use increased concurrently with symptom scores (94% vs 50%, p = 0.02). CONCLUSIONS: The commonly used measures of asthma severity, symptom scores, peak flow rate, and beta-agonist use may not be interchangeable in describing the clinical course. Patients whose beta-agonist use is driven by symptoms tend to be more compliant with use of inhaled corticosteroids.

The effect of comprehensive outpatient pulmonary rehabilitation on dyspnea.

To evaluate the effect of outpatient pulmonary rehabilitation (OPR) on dyspnea, we measured this symptom using a visual analogue scale during graded treadmill exercise testing and with baseline and transitional dyspnea indices (TDI). The latter measure overall dyspnea in three spheres: functional impairment, magnitude of task, and magnitude of effort. Twenty patients with COPD referred for OPR were randomly assigned to either a treatment group (T, n = 10), with dyspnea evaluated at baseline then shortly following a 6-week OPR program, or a control group (C, n = 10), with dyspnea evaluated at baseline then following a 6-week waiting period. No significant change in maximal exercise performance from baseline to repeated testing was observed in either group. Dyspnea at maximum treadmill workload (Dmax), which did not significantly change in C, decreased from 74.4 +/- 18.9 percent at baseline to 50.5 +/- 23.2 percent post-OPR in T (p = 0.006). The Dmax related to minute ventilation (Dmax/VEmax) and oxygen consumption (Dmax/VO2max) also significantly decreased following OPR. The reduction in exertional dyspnea was apparent by the second minute of exercise. Additionally, TDI focal scores were significantly higher in T than C (2.3 +/- 1.06 vs 0.2 +/- 1.75 units, p = 0.006), indicating decreased overall dyspnea following OPR. These results point to significant improvements in both exertional and clinically assessed dyspnea following OPR.

The influence of spring and summer New England meteorologic conditions on the respiratory status of patients with chronic lung disease.

To determine whether meteorologic conditions affect the respiratory status of individuals with chronic lung disease, we asked 14 patients who had completed outpatient pulmonary rehabilitation to record the following information daily during the spring and summer of 1991: (1) dyspnea on arising (morning dyspnea); (2) dyspnea throughout the day (daytime dyspnea); (3) peak expiratory flow rate (PEFR); (4) mood; and (5) the presence of lower respiratory tract infection (LRI). The effect of local meteorologic conditions and LRI frequency on morning and daytime dyspnea, PEFR, and mood were analyzed for spring and summer seasons using a linear regression technique that controlled for first-order autocorrelation. The LRI frequency and the preceding day's respiratory status were the most significant predictors of either season's daily variation in respiratory status. During spring, the only meteorologic condition associated with respiratory status was precipitation: rainfall was directly related to increased morning and daytime dyspnea. Meteorologic conditions were not related to changes in PEFR or mood. During summer, the combination of higher temperature, rise in barometric pressure, and increased LRI frequency best predicted increased morning dyspnea, while the combination of higher temperature and rise in barometric pressure best predicted reduced PEFR. Meteorologic conditions were not related to changes in daytime dyspnea or mood. Precipitation in spring and a combination of high temperature and rise in barometric pressure in summer best predicted deterioration in the respiratory status of this group of patients with chronic lung disease.