More COPD patients than you may realise struggle to inhale from their device^1,2

Footnotes

• * mMRC ≥2. Calculation performed using the percentage of patients in each group (>80%, <80%, >50% and <50%).¹²
• † Denotes patients with suboptimal peak inspiratory flow (sPIF), which is a measure of a patient’s inspiratory effort, or ability to inhale. In this study, suboptimal PIF was defined as ≤60 L/min.² Retrospective chart review of 123 patients hospitalised for acute exacerbation of COPD. Disease severity based upon GOLD classification; patients across all ranges of severity were included.² A retrospective analysis of hospitalised patients enrolled in an AECOPD care plan was performed. Data analysed included PIF, age, sex, length of stay, Charlson Comorbidity Index, COPD Assessment Test Score, Modified Medical Research Council Score, percent predicted FEV₁, FVC, and inspiratory capacity. A PIF ≤60 L/min was defined as suboptimal (sPIF). Outcome measures included 30- and 90- day COPD and all-cause readmissions, and days to next COPD and allcause readmission. Of the 123 subjects, 52% had sPIF. PIF was the only variable (p=0.041) that predicted days to COPD readmission in a multivariate model incorporating age, sex, percent predicted FEV₁, Charlson Comorbidity Index, and inspiratory flow group.²
• # sPIF has been observed in 19–78% of stable outpatients and 32–52% of inpatients before discharge from the hospital after treatment for COPD exacerbation.¹³
• ‡ An observational single-centre, cohort study was conducted including 66 outpatients with COPD. PIF was measured using the In-Check™ Dial with applied resistance of prescribed inhalers. Participants were defined as discordant if measured PIF was <30 L/min and <60 L/min on high- and low-medium resistance devices, respectively, using an inspiratory effort the participants normally used with their prescribed DPI.¹
• § Baseline demographics, clinical characteristics, PIF, and severity of dyspnoea were pooled from two trials (n=525). The first trial was Study 0128 (NCT02518139), a 52-week, tiotropium-controlled, parallel-group, phase 3 safety study, evaluating the safety and tolerability of revefenacin for nebulisation in patients with moderate-to-very severe COPD. The second Study was 0149 (NCT03095456), a 28-day, double-blind, double-dummy, parallel-group phase 3b trial, comparing the effect of once-daily revefenacin for nebulisation administered via Pari LC® Sprint jet nebuliser versus tiotropium administered via HandiHaler® on lung function in patients with moderate (Gold 2) to very severe (Gold 4) COPD and PIFR <60 L/min against the resistance of Diskus. Baseline PIFR was measured using In-Check™ DIAL at the resistance set to HandiHaler in Study 0128 and to Diskus and HandiHaler in Study 0149. Evidence of dyspnoea was measured by mMRC and BDI, and was present across airflow limitation categories. The sPIF subgroup included a higher proportion of GOLD4 patients than the optimal PIF subgroup at baseline.³
• ¶ A retrospective analysis of hospitalised patients, enrolled in an AECOPD care plan, was performed. Data analysed included PIF, age, sex, length of stay, Charlson Comorbidity Index, COPD Assessment Test Score, Modified Medical Research Council Score, percent predicted FEV₁, FVC, and inspiratory capacity. A PIF ≤60 L/min was defined as suboptimal (sPIF). Outcome measures included 30- and 90-day COPD and all-cause readmissions, and days to next COPD and all-cause readmission. Of the 123 subjects, 52% had sPIF. PIF was the only variable (p=0.041) that predicted days to COPD readmission in a multivariate model incorporating age, sex, percent predicted FEV₁, Charlson Comorbidity Index, and inspiratory flow group.¹
• a Fine particles <5 μm.⁶
• ** Denotes patients with suboptimal peak inspiratory flow (sPIF), which is a measure of a patient’s inspiratory effort, or ability to inhale. In this study, suboptimal PIF was defined as ≤60 L/min.
• †† The appropriate inspiratory flow can vary from device to device.¹
• ## Optimal PIF was defined as ≥60 L/min.³

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