Long-term treatment of chronic obstructive pulmonary disease with salmeterol and the additive effect of ipratropium

Abstract

The efficacy and safety of salmeterol alone was compared with the combination of salmeterol plus ipratropium and with placebo during long-term treatment in patients with stable chronic obstructive pulmonary disease. In addition, the single-dose effect in response to the first dose of treatment was studied over 12 h. The patients (n=144; age 64+/-7 yrs, forced expiratory volume in one second (FEV1) 44+/-11% pred) participated in a three-centre double-blind double-placebo parallel group study and were randomized after a run-in period of 2 weeks to receive either salmeterol 50 microg b.i.d., salmeterol 5 microg b.i.d. plus ipratropium 40 microg q.i.d. or placebo for a period of 12 weeks. The single-dose study demonstrated that salmeterol produced a significant increase in FEV1 (peak of 7% pred) and specific airway conductance (sGaw) (maximum of 60% baseline) for > or =12 h. The combination of salmeterol plus ipratropium elicited a greater bronchodilator response (11% and 94% increases respectively) than salmeterol alone during the first 6 h after inhalation. During treatment there were significant improvements in daytime symptom scores and morning peak expiratory flow in both the salmeterol and the salmeterol plus ipratropium groups (p<0.001), with an associated decrease in the use of rescue salbutamol. Improvements in FEV1 and sGaw were greater in the salmeterol plus ipratropium group than in the patients receiving only salmeterol. Thirty-five patients had an exacerbation; 11 (23%) in the salmeterol group (versus placebo NS), six (13%) in the salmeterol plus ipratropium group (versus placebo p<0.01) and 18 (36%) in the placebo group. In conclusion, in patients with severe stable chronic obstructive pulmonary disease, long-term treatment with either salmeterol alone or salmeterol plus ipratropium is safe and effective. There was added benefit from the combination therapy in terms of improvement in airways obstruction, but not for improvement in symptom control or need for rescue salbutamol.