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Biomedical subjects

Katharine Knobil

Publications and source records attributed to Katharine Knobil.

5 recordsLinked to original sources

Effect of fluticasone propionate/salmeterol on lung hyperinflation and exercise endurance in COPD.

STUDY OBJECTIVE: To examine the effect of fluticasone propionate, 250 microg/salmeterol, 50 microg combination (FSC 250/50) twice daily on lung hyperinflation and associated measures of exercise performance in patients with COPD. DESIGN: This was a randomized, double-blind, parallel-group study. PATIENTS: Eligible patients were > or = 40 years old with a diagnosis of COPD, prealbuterol FEV(1) < 70% of predicted, FEV1/FVC ratio > or = 0.70, and functional residual capacity (FRC) > or = 120% of predicted normal. INTERVENTIONS: Patients were randomized to FSC 250/50; salmeterol, 50 microg; or placebo twice daily for 8 weeks. Predose and postdose spirometry, plethysmography, and constant-load cycle cardiopulmonary exercise test evaluations were compared. The primary comparison was FSC 250/50 with placebo. The salmeterol group was included for exploratory comparisons with FSC 250/50. RESULTS: A total of 185 patients (mean baseline FEV1 of 41% predicted) were enrolled. At rest, FSC 250/50 significantly reduced postdose FRC and increased inspiratory capacity (IC) compared with placebo (differences of - 0.35 +/- 0.12 L and 0.33 +/- 0.06 L [mean +/- SE], respectively, at week 8; p > or = 0.003) and increased exercise endurance time (difference, 132 +/- 45 s; p = 0.004). At a standardized time during exercise (isotime), FSC 250/50 increased postdose IC by 0.20 +/- 0.05 L over placebo with associated improvements in tidal volume and minute ventilation (p < 0.05 vs placebo at week 8). Improvement in exercise time was significantly correlated with the increase in IC (r = 0.45, p < 0.001) but not FEV1 (r = 0.23, p = 0.08). Predose comparisons of FSC 250/50 with salmeterol and placebo favored FSC 250/50. CONCLUSION: We conclude that FSC 250/50 decreases lung hyperinflation at rest and during exercise with an associated increase in exercise endurance time when compared with placebo.

Adrenergic beta-Agonists↗

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.

Adrenergic beta-Agonists↗

The efficacy and safety of inhaled fluticasone propionate/salmeterol and ipratropium/albuterol for the treatment of chronic obstructive pulmonary disease: an eight-week, multicenter, randomized, double-blind, double-dummy, parallel-group study.

BACKGROUND: The pathology of chronic obstructive pulmonary disease (COPD) includes both obstructive and inflammatory components. OBJECTIVE: The aim of this study was to confirm the findings of a previous study that compared the efficacy of a combination of 2 short-acting bronchodilators with the use of an inhaled corticosteroid and a long-acting beta-agonist in the treatment of COPD. METHODS: We conducted an 8-week, multicenter, randomized, double-blind, double-dummy, parallel-group study of subjects with moderate to severe COPD to compare fluticasone propionate/salmeterol 250/50 microg BID (FSC) with ipratropium/albuterol 36/206 microg QID (IB/ALB). The primary efficacy measure was morning preadministration forced expiratory volume in 1 second (FEV(1)). Secondary measures were morning peak expiratory flow (PEF), 6-hour FEV(1) AUC, percentage of symptom-free nights, Transition Dyspnea Index (TDI) score, and overall daytime symptom score. Additional measures included sleep symptoms, supplemental albuterol use, and nighttime awakenings due to respiratory symptoms. Safety evaluations were based on clinical adverse events and COPD exacerbations. RESULTS: Baseline characteristics were similar between the FSC (n = 180) and IB/ALB (n = 181) groups, including mean age (63.7 and 65.4 years, respectively), mean body weight (81 and 79 kg, respectively), screening pulmonary function (mean [SD], 43.7% [14.2%] and 41.6% [13.4%] of predicted FEV(1)), race (82% and 91% white), and sex (64% and 62% male). FSC resulted in greater improvements in morning preadministration FEV(1), morning PEF, and 6-hour FEV(1) AUC (all, P < 0.001), TDI score (P = 0.026), overall daytime symptom score (P = 0.024), percentage of symptom-free nights (P = 0.010), nighttime awakenings due to respiratory symptoms (P = 0.002), sleep symptom score (P = 0.003), and percentage of days and nights without rescue albuterol use compared with IB/ALB (P = 0.021 and P < 0.001, respectively). Compared with day 1, the FEV(1) AUC at week 8 increased by 0.38 L-h with FSC and decreased by 0.18 L-h with IB/ALB (P < 0.001 between groups). The type and incidence of adverse events were similar between the 2 groups. One or more adverse event was reported for 81 (45%) and 85 (47%) subjects in the FSC and IB/ALB groups, respectively. CONCLUSION: In this 8-week study, subjects with moderate to severe COPD experienced greater improvements in lung function and symptom measures with FSC than with IB/ALB.

Administration, Inhalation↗

A short-term comparison of fluticasone propionate/salmeterol with ipratropium bromide/albuterol for the treatment of COPD.

BACKGROUND: This is the first comparison of two combination therapies, fluticasone propionate/salmeterol and ipratropium bromide/albuterol (salbutamol), for the treatment of patients with COPD. METHODS: A randomized, double-blind, double-dummy, parallel group, multicenter evaluation of fluticasone propionate/salmeterol 250/50 microg twice daily via DISKUS and ipratropium bromide/albuterol 36/206 microg four times daily via metered-dose inhaler over 8 weeks was conducted at 41 research sites in the US. Morning pre-dose FEV(1), 6-hour serial spirometry, PEF, dyspnea, night-time awakenings, supplemental albuterol use, and patient diary evaluations of symptoms were evaluated. RESULTS: A total of 365 patients with symptomatic COPD were enrolled. The treatment groups were similar in mean age (63.3 and 63.9 years), screening pulmonary function (44.1% and 43.2% of predicted FEV(1)), race (96% and 95% White), and sex distribution (59% and 60% male). Both fluticasone propionate/salmeterol and ipratropium bromide/albuterol improved lung function, symptoms, and supplemental albuterol use compared with baseline. Fluticasone propionate/salmeterol was more effective than ipratropium bromide/albuterol for improvement in morning pre-dose FEV(1), morning PEF, 6-hour FEV(1) area under the curve (AUC(6)), Transition Dyspnea Index (TDI) focal score, daytime symptom score, night-time awakenings, sleep symptoms, and albuterol-free nights (p < or = 0.013). Compared with day 1, at week 8 the FEV(1) AUC(6) significantly increased with fluticasone propionate/salmeterol and significantly decreased with ipratropium bromide/albuterol (p < or = 0.003). The incidence of adverse events was similar between treatment groups, except for a higher incidence of oral candidiasis with fluticasone propionate/salmeterol. CONCLUSIONS: Short-term treatment with the combined inhaled corticosteroid and long-acting beta(2)-adrenoceptor agonist fluticasone propionate/salmeterol resulted in greater control of lung function and symptoms than combined ipratropium bromide/albuterol bronchodilator therapy, in patients with COPD.

Administration, Inhalation↗

Loss of response to treatment with leukotriene receptor antagonists but not inhaled corticosteroids in patients over 50 years of age.

BACKGROUND: There are limited published data describing the relative efficacy of available treatment options in younger versus older patients with persistent asthma. OBJECTIVE: To compare the efficacy of fluticasone propionate (FP) and zafirlukast (Z) in younger (12 to 49 years of age) versus older (50 years and older) patients with asthma. METHODS: A retrospective analysis of five randomized, double-blind, double-dummy studies 4 to 12 weeks in duration of 1,742 patients <50 years of age and 243 patients aged 50 years or older. Interventions were inhaled fluticasone propionate (FP) 88 microg, oral Z 20 mg, or placebo twice daily. RESULTS: Treatment with FP resulted in significantly greater improvements than Z in all efficacy measurements (except for nighttime awakenings) regardless of age. In older patients, treatment with FP significantly increased pulmonary function compared with Z: FEV (FP= +0.19 L; placebo = -0.34 L; Z = -0.06 L); AM peak expiratory flow rate [PEFR] (FP = +25 L/minute; placebo = -18 L/minute; Z = +4 L/minute); PM PEFR (FP = +24 L/minute; placebo = -24 L/minute; Z = +5 L/minute; P < or = 0.023; for all comparisons). Compared with Z, treatment with FP in older patients also resulted in significantly greater increases in the percentage of symptom-free days (25% vs 13%) and rescue-free days (35% vs 17%); and significantly greater reductions in albuterol use (-1.6 vs -0.3 puffs/day) and the percentage of patients with exacerbations (2.7% vs 14.3%; P < or = 0.031). CONCLUSIONS: Regardless of age, treatment with FP in patients with asthma significantly improved pulmonary function and overall asthma control. In contrast, treatment with Z in older patients with asthma resulted in small improvements in asthma symptoms, whereas lung function improved minimally or not at all, and exacerbations increased. These data suggest that FP effectively controls inflammation in older patients, whereas Z may mask inflammation and may not provide the level of bronchodilatory or anti-inflammatory activity needed for effective asthma control in older patients.

Adolescent↗