The Combined Effect Of Tiotropium And Formoterol On The Functional Status Of Patients With Moderate-to-severe COPD

This double blinded placebo controlled pilot study examined the use of combined inhaled medication for patients with moderate-to-severe COPD. The inhalation of formoterol versus placebo was studied when combined with the routine use of tiotropium. Maximizing bronchodilitation through the use of combination inhaler therapy is felt to be superior to the use of a single inhaled medication, yet few studies are found in the literature. Currently the Global Initiative for Obstructive Lung Disease (GOLD) recommends the use of combination inhaled therapy in patients with moderate-to-severe COPD. This study of 18 patients with moderate-to-severe COPD measured the effects on the functional status of patients as determined by FEV1 and FVC via spirometry, the distance walked during a six-minute walk test, and the patients' perception of dyspnea and fatigue via the Modified Borg Scale. Statistically significant improvement was demonstrated in all measures except the Modified Borg Scale. Statistically significant spirometric changes of both the FEV1 and FVC occurred, but were not increased by the 12% and 200 mL change stated as clinically significant by the American Thoracic Society. One patient was found to have a clinically significant change in FEV1, and five patients obtained clinically significant changes in their FVC with formoterol. The distance walked in six-minutes was found to be statistically significant, but did not achieve the commonly accepted clinically significant change of 35 meters. Only two patients were able to walk a clinically significant distance after inhaling formoterol. Demographic data was not found to identify discerning characteristics that would be beneficial for distinguishing which patients benefited most from the combined therapy. This study found improvements in both the six-minute walk test and in spirometry that were statistically but not clinically significant. Subjective dyspnea and fatigue with the use a Modified Borg Scale was not found to be statistically significant. It is recommended that patients continue to take the combined therapy of formoterol and tiotropium until research contradicts this evidence. More research is needed to ascertain the best measurement of functional status for patients with COPD and to identify which patients will benefit from combination therapy.