Profiles of measured and perceived bronchodilation. A placebo-controlled cross-over trial comparing formoterol and salmeterol in moderate persistent asthma.

BACKGROUND AND OBJECTIVE: Long-acting beta(2)-agonists have acquired an indispensable position in the management of bronchial symptoms in patients with asthma. The objective of this study was to compare onset-of-action and clinical effectiveness of formoterol and salmeterol during 2 weeks of treatment. We also investigated the association between bronchodilator effects and perceived relieve of dyspnoea. METHODS: A multi-centre randomized double-blind placebo-controlled cross-over trial was performed in 35 subjects with moderate persistent asthma. Treatment periods existed of 2 weeks formoterol (12 microg bid), salmeterol (50 microg bid) and placebo, all administered by pressurized metered dose inhaler. FEV(1) and Visual Analogue Scale (VAS) scores were repeatedly measured until 180 min post-bronchodilation (post-BD), before as well as after each treatment period. Onset-of-action was defined as a >/=15% increase in FEV(1). Subjects kept diaries of morning and evening PEFR values and use of rescue bronchodilator. RESULTS: Formoterol and salmeterol both caused a significant increase in FEV(1) (0.45L [95% CI 0.01, 0.80] and 0.27L [95% CI 0.08, 0.62] respectively). At 3' post-BD, three times as many subjects demonstrated onset-of-action on formoterol compared to salmeterol (36% versus 13%, P = 0.063), at 6' post-BD 42% versus 27% (P = 0.063). VAS scores were similar for formoterol and salmeterol at pre-treatment assessment, but tended to be higher for formoterol after 2weeks treatment. No differences between formoterol and salmeterol were observed for PEFR values or use of rescue medication. 50% of the subjects preferred formoterol, 29% salmeterol (P < 0.001). Significant associations between FEV(1) and VAS ratings existed only at 10', 15' and 30' post-BD, not before or after these time points. CONCLUSION: The earlier described faster onset-of-action of formoterol as compared to a equipotent dosage of salmeterol was confirmed in this study. Perception of decreasing airflow obstruction may be delayed after acute bronchodilation.

Improved health outcomes in patients with COPD during 1 yr's treatment with tiotropium.

Tiotropium, a novel once-daily inhaled anticholinergic, has been shown to improve lung function over a 24-h period. In order to extend these findings, health-outcomes were evaluated over 1 yr in chronic obstructive pulmonary disease (COPD) patients. Spirometric results, peak expiratory flow rate (PEFR), salbutamol use and effects on dyspnoea, health-related quality of life and COPD exacerbations were assessed in two identical 1-yr randomized double-blind double-dummy studies of tiotropium 18 microg once daily (n=356) compared with ipratropium 40 microg q.i.d. (n=179). Screening forced expiratory volume in one second (FEV1) were 1.25+/-0.43 L (41.9+/-12.7% of the predicted value) (tiotropium) and 1.18+/-0.37 L (39.4+/-10.7% pred) (ipratropium). Trough FEV1 at 1 yr improved by 0.12+/-0.01 L with tiotropium and declined by 0.03+/-0.02 L with ipratropium (p<0.001). Significant improvement in PEFR, salbutamol use, Transition Dyspnea Index focal score, and the St George's Respiratory Questionnaire total and impact scores were seen with tiotropium (p<0.01). Tiotropium reduced the number of exacerbations (by 24%, p<0.01), and increased time to first exacerbation (p<0.01) and time to first hospitalization for a COPD exacerbation (p<0.05) compared with ipratropium. Apart from an increased incidence of dry mouth in the tiotropium group, adverse events were similar between treatments. Tiotropium was effective in improving dyspnoea, exacerbations, health-related quality of life and lung function in patients with chronic obstructive pulmonary disease, and exceeds the benefits seen with ipratropium. The data support the use of tiotropium once-daily as first-line maintenance treatment in patients with chronic obstructive pulmonary disease.