Evaluation of an ambulatory system for the quantification of cough frequency in patients with chronic obstructive pulmonary disease

BACKGROUND: To date, methods used to assess cough have been primarily subjective, and only broadly reflect the impact of chronic cough and/or chronic cough therapies on quality of life. Objective assessment of cough has been attempted, but early techniques were neither ambulatory nor feasible for long-term data collection. We evaluated a novel ambulatory cardio-respiratory monitoring system with an integrated unidirectional, contact microphone, and report here the results from a study of patients with COPD who were videotaped in a quasi-controlled environment for 24 continuous hours while wearing the ambulatory system. METHODS: Eight patients with a documented history of COPD with ten or more years of smoking (6 women; age 57.4 ± 11.8 yrs.; percent predicted FEV(1 )49.6 ± 13.7%) who complained of cough were evaluated in a clinical research unit equipped with video and sound recording capabilities. All patients wore the LifeShirt(® )system (LS) while undergoing simultaneous video (with sound) surveillance. Video data were visually inspected and annotated to indicate all cough events. Raw physiologic data records were visually inspected by technicians who remained blinded to the video data. Cough events from LS were analyzed quantitatively with a specialized software algorithm to identify cough. The output of the software algorithm was compared to video records on a per event basis in order to determine the validity of the LS system to detect cough in COPD patients. RESULTS: Video surveillance identified a total of 3,645 coughs, while LS identified 3,363 coughs during the same period. The median cough rate per patient was 21.3 coughs·hr(-1 )(Range: 10.1 cghs·hr(-1 )– 59.9 cghs·hr(-1)). The overall accuracy of the LS system was 99.0%. Overall sensitivity and specificity of LS, when compared to video surveillance, were 0.781 and 0.996, respectively, while positive- and negative-predictive values were 0.846 and 0.994. There was very good agreement between the LS system and video (kappa = 0.807). CONCLUSION: The LS system demonstrated a high level of accuracy and agreement when compared to video surveillance for the measurement of cough in patients with COPD

A 28-day, randomized, double-blind, placebo-controlled, parallel group study of nebulized revefenacin in patients with chronic obstructive pulmonary disease

Abstract Background Revefenacin is a once-daily long-acting muscarinic antagonist (LAMA) in clinical development for the treatment of patients with chronic obstructive pulmonary disease (COPD). In a dose-ranging study, nebulized once-daily revefenacin had a long duration of action in patients after 7 days’ administration of doses up to 700 μg. In this multiple-dose study, the bronchodilation efficacy and adverse events profile were characterized in patients administered nebulized revefenacin once daily for 28 days. Methods A total of 355 COPD patients (mean age 62 years, mean forced expiratory volume in 1 s [FEV1] 44% of predicted) were randomized in a double-blind, placebo-controlled parallel group study. Inhaled corticosteroids as well as short-acting bronchodilators were permitted. Once-daily treatments (44, 88, 175 or 350 μg revefenacin or matching placebo) were administered by a standard jet nebulizer, for 28 days. The primary endpoint was change from baseline in D28 trough FEV1, and secondary endpoints included weighted mean FEV1 over 0 to 24 h and rescue medication (albuterol) use. Safety evaluations included adverse events, laboratory assessments, electrocardiograms and 24-h Holter profiles. Results Revefenacin (88, 175 and 350 μg) significantly improved D28 trough FEV1 over placebo (187.4, 166.6 and 170.6 mL, respectively, all p < 0.001); 44 μg produced a sub-therapeutic response. At doses ≥88 μg, more than 80% of patients achieved at least a 100-mL increase from baseline FEV1 in the first 4 h post dose compared with 33% of placebo patients. For doses ≥88 μg, D28 24 h weighted mean differences from placebo for FEV1 were numerically similar to respective trough FEV1 values, indicating bronchodilation was sustained for 24 h post dose. Doses ≥88 μg reduced the average number of albuterol puffs/day by more than one puff/day. The 350 μg dose did not demonstrate additional efficacy over that observed with 175 μg revefenacin. Revefenacin was generally well tolerated, with minimal reports of systemic anti-cholinergic effects. Conclusions These data suggest that 88 and 175 μg revefenacin are appropriate doses for use in longer-term safety and efficacy trials. Revefenacin offers the potential for the first once-daily LAMA for nebulization in patients with COPD who require or prefer a nebulized drug delivery option. Trial registration ClinicalTrials.gov NCT02040792 . Registered January 16, 2014