Prevalence and COPD phenotype for a suboptimal peak inspiratory flow rate against the simulated resistance of the Diskus® dry powder inhaler

Clinical characteristics of chronic obstructive pulmonary disease patients with superoptimal peak inspiratory flow rate

Characteristics of chronic obstructive pulmonary disease (COPD) patients with superoptimal peak inspiratory flow rates (PIFR) has not been thoroughly investigated. This study aimed to compare the characteristics between COPD patients with superoptimal PIFR and those with optimal and sub-optimal PIFR. PIFR was measured using In-Check DIAL G16 and categorized into sub-optimal (PIFR lower than that required by the patient's device), optimal, and superoptimal (peak PIFR ≥ 90 L/min). Considering COPD patients with sub-optimal PIFR as the reference group, analyses were performed to identify PIFR-related factors. Subgroup analysis was performed according to the forced expiratory volume in 1 s (FEV1) % of the predicted value (%pred). Among 444 post-bronchodilator-confirmed COPD patients from seven tertiary hospitals in South Korea, 98, 223, and 123 were classified into the sub-optimal, optimal, and superoptimal PIFR groups, respectively. The superoptimal PIFR group were younger, had an increased proportion of males, a higher body mass index, lowest number of comorbidities and less frequent exacerbation in the previous year, as well as the highest forced vital capacity %pred. The adjusted odds ratio for frequent exacerbation in the previous year was lower in the superoptimal PIFR group than in the sub-optimal PIFR group and was more pronounced in patients with an FEV1%pred of < 70%. COPD patients with superoptimal PIFR have clinical characteristics different from those patients with the sub-optimal and optimal PIFR. Having a high inspiratory flow may be a favorable trait in COPD.

Suboptimal peak inspiratory flow rate in dry-powder inhaler users for chronic obstructive pulmonary disease in Korea

BACKGROUND

A suboptimal peak inspiratory flow rate (PIFR) in dry-powder inhaler (DPI) users can lead to insufficient therapeutic effects in the treatment of chronic obstructive pulmonary disease (COPD). However, few data on the prevalence of and factors associated with suboptimal PIFR in Korean patients with COPD are available.

METHODS

We conducted a cross-sectional study of patients with COPD who had been using DPIs for more than three months. PIFR was measured using an In-Check DIAL G16 device. Suboptimal PIFR was defined as below the resistance-matched threshold. Multivariable logistic regression analysis was used to determine factors associated with suboptimal PIFR.

RESULTS

Of 444 DPI users with COPD, the rate of suboptimal PIFR was 22.0 % (98/444). In a multivariable analysis, significant factors associated with suboptimal PIFR were age (adjusted odds ratio [aOR] = 1.06 by 1-year increase; 95 % confidence interval [CI] = 1.02-1.09), male sex (aOR = 0.28; 95 % CI = 0.11-0.73), body mass index (BMI) (aOR = 0.91 by 1 kg/m2 increase; 95 % CI = 0.85-0.99), post-bronchodilator forced vital capacity (FVC) %pred (aOR = 0.97 by 1%pred increase; 95 % CI = 0.95-0.99), and In-Check DIAL R2-type inhaler [medium-low resistance] use (aOR = 3.70 compared with R1-type inhalers [low resistance]; 95 % CI = 2.03-7.03).

CONCLUSIONS

In Korea, more than one-fifth of DPI users with COPD had a suboptimal PIFR. The factors associated with suboptimal PIFR were age, female gender, low BMI, low FVC, and R2-type inhaler use. Therefore, clinicians should carefully evaluate the possibility of suboptimal PIFR when prescribing DPIs.

Changes in Peak Inspiratory Flow After Acute Bronchodilation: An Observational Study of Patients with Stable Chronic Obstructive Pulmonary Disease

Introduction: Identifying factors influencing peak inspiratory flow (PIF) is essential for aerosol drug delivery in stable patients with chronic obstructive pulmonary disease. While a minimum PIF for dry powder inhalers (DPIs) is established, acute bronchodilator (BD) effects on PIF remain unknown. Materials and Methods: An inspiratory flow meter (In-Check™ DIAL) was used to measure PIF in stable patients during a 24-week observational cross-sectional study. Additionally, bronchodilator responsiveness (BDR) was determined using the In-Check DIAL device and spirometry. Patients received four puffs of albuterol, and pre- and post-BD PIF, forced expiratory volume in one second (FEV1), and forced vital capacity were measured. Sixty-three patients completed acute BDR data collection from July 31, 2019, to November 9, 2021. Primary endpoints were pre- and post-BD spirometry and PIF. Statistical analyses included PIF correlations with FEV1. BD change was assessed according to inhaler resistance and sex (subgroup analysis). Results: Median patient age was 64.8 years, 85.7% were non-Hispanic White, and 57.1% were female. The median increase in absolute PIF (In-Check DIAL) was 5.0 L/min, and the % PIF change was 8.9%. With albuterol, 57.1% experienced a PIF BD change >5.0%, whereas 49.2% experienced a change >10.0%. Similarly, 55.6% experienced an FEV1 BD change >5.0% and 28.6% had a >10.0% FEV1 BD change with albuterol. PIF was weakly correlated with FEV1 BD change (absolute; % PIF; r = 0.28 [p = 0.02]; r = 0.21 [p = 0.11]). Pre- and post-BD median PIF were 75.5 and 83.5 L/min for low-to-medium-resistance DPI and 45.0 and 52.0 L/min for high-resistance, respectively. The median increases in pre- and post-BD PIF were 9.0 L/min in males and 4.5 L/min in females. In contrast to when using the In-Check DIAL device, we observed no consistent bronchodilatory effects on PIF measured by spirometry. Conclusions: Using the In-Check DIAL device, ∼50% of patients experienced >10% PIF increase after acute BD, potentially enhancing medication lung deposition. Further research is required to understand PIF's impact on medication delivery. ClinicalTrials.gov Identifier: NCT04168775.

Suboptimal peak inspiratory flow rate: a noticeable risk factor for inhaler concordance in patients with chronic airway diseases

BACKGROUND

Inhaler concordance and the peak inspiratory flow rate (PIFR) are important determinants of treatment effects in patients with chronic airway diseases. Adequate PIFR is required for driving aerosol medication into the lower respiratory tract. However, the relationship between them has not been discussed previously. This study aimed to describe the characteristics of inhaler concordance and PIFR in Chinese patients with chronic airway diseases and discuss the associated variables and the relationship between them.

METHODS

In this single-centre, observational study, a total of 680 patients with chronic airway diseases were enrolled from July 2021 to April 2023. We collected data on the socio-demographic and clinical variables of inhaler concordance using the test of adherence to inhalers (TAI) and PIFR. Multivariate logistic regression was conducted to examine variables related to inhaler concordance and PIFR.

RESULTS

A total of 49.4% of patients had low concordance. Patients with chronic obstructive pulmonary disease (COPD) were more concordant than patients with asthma (mean TAI score: 43.60 vs 41.20; p<0.01), while there was no difference in concordance between the asthma-COPD overlap group and the asthma or COPD group. Suboptimal PIFR (adjusted OR, 1.61; 95% CI 1.04 to 2.51) increased the risk of poor concordance among all patients, while triple therapy (adjusted OR, 0.60; 95% CI 0.35 to 0.86) reduced the risk. A total of 54.9% of patients had suboptimal PIFR. Older age, lower educational level, use of dry powder inhalers and lower forced expiratory volume in 1 s % predicted were significantly correlated with insufficient PIFR. Subgroup analysis revealed a greater proportion of patients with insufficient PIFR during exacerbation than during the stable phase (61.7% vs 43.5%, p<0.001).

CONCLUSION

Inhaler concordance was low, and suboptimal PIFR was a risk factor for poor concordance among Chinese patients with chronic airway diseases. In addition, current inhalation devices may not be suitable, and PIFR reassessment should be considered for patients with COPD during exacerbation.

TRIAL REGISTRATION NUMBER

The study was registered in chictr.org.cn (ChiCTR2100052527) on 31 October 2021.

Prevalence and Factors Affecting the Optimal and Non-optimal Peak Inspiratory Flow Rate in Stable and Exacerbation Phases of Chronic Obstructive Pulmonary Disease and Bronchial Asthma in India

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) and bronchial asthma pose significant threats and challenges to global health care, emphasizing the need for precise inhaler therapies to overcome this burden. The optimal peak inspiratory flow rate (PIFR) is a crucial determinant for the right selection and effective use of an inhaler device. It also helps to improve the treatment effectiveness of obstructive airway diseases worldwide as it allows effective drug delivery to distal airways and lung parenchyma. It is used as a selection criterion by physicians around the world for selecting personalized inhaler devices.

OBJECTIVE

To find out the optimal and non-optimal PIFR prevalence and its influencing factors in stable and exacerbation phases of COPD and bronchial asthma in Tamil Nadu, India.

METHODOLOGY

It is a single-center, observational, cross-sectional study conducted from February 2022 to August 2023. The patients who meet the diagnostic criteria specified by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines for COPD and the Global Initiative for Asthma (GINA) guidelines for bronchial asthma are enrolled in our study. The PIFR was measured using a hand-held digital spirometry device, along with demographic data collection. Statistical analyses, including t-tests and chi-square tests, were performed using SPSS version 21 (IBM Corp., Armonk, NY).

RESULTS

Gender, height, and disease severity significantly impacted the PIFR. Females, normal BMI individuals, and those with moderate disease severity exhibited higher optimal PIFR rates. Stable or exacerbation phases, disease, and smoking status do not influence either optimal or non-optimal PIFR. Notably, substantial differences in lung function parameters were observed between optimal (60-90 L/min) and non-optimal PIFR (insufficient: <30 L/min, suboptimal: 30-60 L/min, excessive: >90 L/min) groups, highlighting their impact on respiratory health.

CONCLUSION

This study emphasizes the importance of personalized inhaler strategies, considering gender, height, and disease severity. Proper inhaler device selection, continuous monitoring of inhaler technique, and tailored inhaler education at every OPD visit are vital for optimizing effective COPD and bronchial asthma management and improving adherence to treatment.

Clinical Burden of Chronic Obstructive Pulmonary Disease in Patients with Suboptimal Peak Inspiratory Flow

Introduction

Many patients with chronic obstructive pulmonary disease (COPD) may derive inadequate benefit from dry powder inhalers (DPIs) because of suboptimal peak inspiratory flow (sPIF).

Objectives

To assess the clinical burden of COPD by characterizing the clinical characteristics of participants with sPIF against medium-low resistance DPIs versus those with optimal PIF (oPIF) from two phase 3 clinical trials.

Methods

Baseline data were collected from two randomized, controlled, phase 3 trials (NCT03095456; NCT02518139) in participants with moderate-to-severe COPD. oPIF (60 L/min) against the medium-low resistance DPIs was used as the threshold for defining the PIF subgroups (<60 L/min (sPIF) vs ≥60 L/min (oPIF)).

Results

Most participants included in this analysis were White (92%) and male (63%); the mean (range) age was 65 (43-87) years. Participants with sPIF had significantly greater dyspnea than those with oPIF as measured using the modified Medical Research Council scoring (mean (95% CI): 2.1 (2.0-2.2) vs 1.6 (1.4-1.7); P  < 0.001) and baseline dyspnea index (mean (95% CI): 5.1 (4.9-5.4) vs 6.1 (5.8-6.3); P  < 0.001). Based on COPD Assessment Test scores, participants with sPIF had a higher COPD symptom burden than those with oPIF (mean (95% CI): 21.5 (19.7-23.3) vs 19.5 (18.6-20.4); P = 0.05).

Conclusion

In these trials, participants with COPD who had sPIF against the medium-low resistance DPIs had more dyspnea and worse health status than those with oPIF. These results demonstrate that sPIF is associated with a higher clinical burden as measured by patient-reported outcomes.

Aerosol Plumes of Inhalers Used in COPD

INTRODUCTION

The selection of inhaler device is of critical importance in chronic obstructive pulmonary disease (COPD) as the interaction between a patient's inhalation profile and the aerosol characteristics of an inhaler can affect drug delivery and lung deposition. This study assessed the in vitro aerosol characteristics of inhaler devices approved for the treatment of COPD, including a soft mist inhaler (SMI), pressurized metered-dose inhalers (pMDIs), and dry powder inhalers (DPIs).

METHODS

High-speed video recording was used to visualize and measure aerosol velocity and spray duration for nine different inhalers (one SMI, three pMDIs, and five DPIs), each containing dual or triple fixed-dose combinations of long-acting muscarinic receptor antagonists and long-acting β2-agonists, with or without an inhaled corticosteroid. Measurements were taken in triplicate at experimental flow rates of 30, 60, and 90 l/min. Optimal flow rates were defined based on pharmacopoeial testing requirements: 30 l/min for pMDIs and SMIs, and the rate achieving a 4-kPa pressure drop against internal inhaler resistance for DPIs. Comparison of aerosol plumes was based on the experimental flow rates closest to the optimal flow rates.

RESULTS

The Respimat SMI had the slowest plume velocity (0.99 m/s) and longest spray duration (1447 ms) compared with pMDIs (velocity: 3.65-5.09 m/s; duration: 227-270 ms) and DPIs (velocity: 1.43-4.60 m/s; duration: 60-757 ms). With increasing flow rates, SMI aerosol duration was unaffected, but velocity increased (maximum 2.63 m/s), pMDI aerosol velocity and duration were unaffected, and DPI aerosol velocity tended to increase, with a more variable impact on duration.

CONCLUSIONS

Aerosol characteristics (velocity and duration of aerosol plume) vary by inhaler type. Plume velocity was lower and spray duration longer for the SMI compared with pMDIs and DPIs. Increasing experimental flow rate was associated with faster plume velocity for DPIs and the SMI, with no or variable impact on plume duration, whereas pMDI aerosol velocity and duration were unaffected by increasing flow rate.

Consideration and Assessment of Patient Factors When Selecting an Inhaled Delivery System in COPD

Because guidelines and strategies for pharmacologic treatment of COPD focus on specific classes of inhaled medications, there is an unmet need for information to guide health care professionals for selecting an inhaled medication delivery system that matches the unique characteristics of individual patients. This article provides guidance for selecting an inhaled medication delivery system based on three "key" patient factors: cognitive function, manual dexterity/strength, and peak inspiratory flow. In addition, information is provided about specific tests to assess these patient factors. Cognitive impairment with an estimated prevalence of 25% among patients with COPD adversely affects patients' ability to correctly use a handheld device. To our knowledge, the prevalence of impaired manual dexterity/strength has not been reported in those with COPD. However, 79% of patients with COPD have reported one or more physical impediments that could influence their ability to manipulate an inhaler device. The measurement of peak inspiratory flow against the simulated resistance (PIFr) of a dry powder inhaler establishes whether the patient has the inhalation ability for creating optimal turbulent energy within the device. A suboptimal PIFr for low to medium-high resistance dry powder inhalers has been reported in 19% to 84% of stable outpatients with COPD. Health care professionals should consider cognitive function, manual dexterity/strength, and PIFr in their patients with COPD when prescribing inhaled pharmacotherapy. Impairments in these patient factors are common among those with COPD and can affect the individual's competency and effectiveness of using inhaled medications delivered by handheld devices.

Exploration of quality criteria for the detection of peak inspiratory flow under different resistance conditions

BACKGROUND

At present, robust quality criteria and methods for the assessment of Peak inspiratory flow meter performance are lacking.

OBJECTIVE

A standard flow-volume simulator for quality control analyses of an inhalation assessment device was utilized with different simulated resistance levels in order to propose a quality testing method and associated standard for this device type.

METHODS

A standard flow-volume simulator was utilized to assess the performance of an In-Check DIAL® (Device I) and an intelligent inhalation assessment device (Device P) at a fixed volume and flow rate. Indices used to evaluate these two instruments included repeatability, accuracy, linearity, and impedance.

RESULTS

Both devices exhibited good repeatability (<± 3 L/min). The difference between test results and standard simulator values for Device P was less than ± 5 L/min at resistance level R1 but higher than ± 5 L/min at resistance levels R2-5, while Device I were greater than 5 L/min at all resistance levels. The relative error for Device P was <± 10% at resistance levels R1, R2, and R4, but > 10% at resistance levels R3 and R5. The relative error values for Device I at all five resistance levels were > 10%. Device P passed the linearity test at the R2 resistance level, while Device I partially passed the linearity test at all five resistance levels.

CONCLUSION

Standard monitoring methods and standards provide a valuable approach to the more reliable clinical assessment and application of these instruments.

High inhaler resistance does not limit successful inspiratory maneuver among patients with asthma or COPD

INTRODUCTION

There has been an active discussion on the sustainability of inhaler therapy in respiratory diseases, and it has cast a shadow on pMDIs which rely on propellant with high global warming potential (GWP). DPIs offer a lower GWP and effective alternative, but there has been concern whether all patients can generate sufficient inspiratory effort to disperse the drug. This review focuses on airflow resistance of DPIs and its clinical relevance.

AREAS COVERED

For this narrative review, we searched the literature for studies comparing flow patterns with different devices. We also included a section on clinical trials comparing reliever administration with DPI, pMDI with spacer, and nebulizer during exacerbation.

EXPERT OPINION

The evidence supports the efficacy of DPIs irrespective of respiratory condition or age of the patient even during acute exacerbations. Air flow resistance does not limit the use of DPIs and the patients were able to generate sufficient inspiratory flow rate with almost any device studied. None of 16 identified clinical trials comparing reliever administration via DPIs to other types of devices during exacerbation or bronchial challenge showed statistically significant difference between the device types in FEV1 recovery. DPIs performed as well as other types of inhaler devices even during asthma or COPD exacerbation.

A review of upper airway physiology relevant to the delivery and deposition of inhalation aerosols

Developing effective oral inhaled drug delivery treatment strategies for respiratory diseases necessitates a thorough knowledge of the respiratory system physiology, such as the differences in the airway channel's structure and geometry in health and diseases, their surface properties, and mechanisms that maintain their patency. While respiratory diseases, such as chronic obstructive pulmonary disease (COPD) and asthma and their implications on the lower airways have been the core focus of most of the current research, the role of the upper airway in these diseases is less known, especially in the context of inhaled drug delivery. This is despite the fact that the upper airway is the passageway for inhaled drugs to be delivered to the lower airways, and their replicas are indispensable in current standards, such as the cascade impactor experiments for testing inhaled drug delivery technology. This review provides an overview of upper airway collapsibility and their mechanical properties, the effects of age and gender on upper airway geometry, and surface properties. The review also discusses how COPD and asthma affect the upper airway and the typical inhalation flow characteristics exhibited by the patients with these diseases.

A Predictive Machine Learning Tool for Asthma Exacerbations: Results from a 12-Week, Open-Label Study Using an Electronic Multi-Dose Dry Powder Inhaler with Integrated Sensors

PURPOSE

Machine learning models informed by sensor data inputs have the potential to provide individualized predictions of asthma deterioration. This study aimed to determine if data from an integrated digital inhaler could be used to develop a machine learning model capable of predicting impending exacerbations.

PATIENTS AND METHODS

Adult patients with poorly controlled asthma were enrolled in a 12-week, open-label study using ProAir® Digihaler®, an electronic multi-dose dry powder inhaler (eMDPI) with integrated sensors, as reliever medication (albuterol, 90 µg/dose; 1-2 inhalations every 4 hours, as needed). Throughout the study, the eMDPI recorded inhaler use, peak inspiratory flow (PIF), inhalation volume, inhalation duration, and time to PIF. A model predictive of impending exacerbations was generated by applying machine learning techniques to data downloaded from the inhalers, together with clinical and demographic information. The generated model was evaluated by receiver operating characteristic area under curve (ROC AUC) analysis.

RESULTS

Of 360 patients included in the predictive analysis, 64 experienced a total of 78 exacerbations. Increased albuterol use preceded exacerbations; the mean number of inhalations in the 24-hours preceding an exacerbation was 7.3 (standard deviation 17.3). The machine learning model, using gradient-boosting trees with data from the eMDPI and baseline patient characteristics, predicted an impending exacerbation over the following 5 days with an ROC AUC of 0.83 (95% confidence interval: 0.77-0.90). The feature of the model with the highest weight was the mean number of daily inhalations during the 4 days prior to the day the prediction was made.

CONCLUSION

A machine learning model to predict impending asthma exacerbations using data from the eMDPI was successfully developed. This approach may support a shift from reactive care to proactive, preventative, and personalized management of chronic respiratory diseases.

Chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity, mortality, and health-care use worldwide. COPD is caused by exposure to inhaled noxious particles, notably tobacco smoke and pollutants. However, the broad range of factors that increase the risk of development and progression of COPD throughout the life course are increasingly being recognised. Innovations in omics and imaging techniques have provided greater insight into disease pathobiology, which might result in advances in COPD prevention, diagnosis, and treatment. Although few novel treatments have been approved for COPD in the past 5 years, advances have been made in targeting existing therapies to specific subpopulations using new biomarker-based strategies. Additionally, COVID-19 has undeniably affected individuals with COPD, who are not only at higher risk for severe disease manifestations than healthy individuals but also negatively affected by interruptions in health-care delivery and social isolation. This Seminar reviews COPD with an emphasis on recent advances in epidemiology, pathophysiology, imaging, diagnosis, and treatment.

Lung Function Can Predict the Expected Inspiratory Airflow Rate through Dry Powder Inhalers in Asthmatic Adolescents

Several factors affect drug delivery from dry powder inhalers (DPIs). Some are related to patient’s physiological characteristics, while others depend on DPIs’ technical aspects. The patient’s inspiratory airflow rate (IAR) affects the pressure drop and the turbulence needed to disaggregate the powder inside a DPI. The present study investigated whether lung function limitations occurring in asthmatic adolescents affect their IAR when inhaling through a DPI simulator. Eighteen consecutive adolescents with asthma were recruited, and IAR was randomly assessed at low-, mid-, and high-resistance regimens. A multiple logistic model was developed to evaluate the association of patients’ lung function characteristics and devices’ resistance with the probability to achieve the expected IAR (E-IAR). The mean value of E-IAR achieved seemed to be sex- and age-independent. Low- and high-resistance regimens were less likely to consent the E-IAR level (odds ratio [OR] = 0.035 and OR = 0.004, respectively). Only the basal residual volume and the inspiratory resistance, but not the Forced Expiratory Volume in 1 s (FEV1), seemed to affect the extent of IAR in asthmatic adolescents (OR = 1.131 and OR = 0.290, respectively). The results suggest that the assessment of current lung function is crucial for choosing the proper DPI for asthmatic adolescents.

Prospective Evaluation of Exacerbations Associated with Suboptimal Peak Inspiratory Flow Among Stable Outpatients with COPD

Purpose

A suboptimal peak inspiratory flow (PIF) against a dry powder inhaler (DPI) may result in ineffective inhalation of medications, which may affect outcomes. The primary objective of this study was to examine the association between PIF status and COPD exacerbations among outpatients with moderate to very severe COPD.

Patients and Methods

This was a prospective, observational study of patients from 7 US outpatient centers. PIF was measured using an inspiratory flow meter (In-Check™ DIAL G16) set to medium low resistance. Patients were classified by suboptimal (<60 L/min) or optimal PIF (≥60 L/min). The primary outcome was the proportion of patients with moderate/severe COPD exacerbations collected by medical record review over 12 months. Secondary outcomes were time to first exacerbation and mortality.

Results

Of 474 patients screened, 38.8% had suboptimal PIF, and 71 patients with optimal PIF were excluded from the study. The enrolled sample included 184 and 219 patients with suboptimal and optimal PIF, respectively. Suboptimal PIF was associated with shorter stature (66.6±4.1 vs 67.8±3.8 inches, P = 0.002), female sex (45.1 vs 34.7%, P = 0.033), Black race (27.2 vs 11.0%, P < 0.001), and greater symptom burden (CAT: 22.3±7.7 vs 19.0±7.0, P < 0.001; mMRC: 2.0±1.1 vs 1.7±1.1, P = 0.003). The proportion of patients with COPD exacerbations at 12 months was not significantly different (29.3 vs 27.9%, P = 0.751). Suboptimal PIF was associated with shorter time to first COPD exacerbation (3.8±2.7 vs 4.9±3.0 months, P = 0.048). The mortality rate at 12 months was higher in the suboptimal cohort but not significantly different (6.5 vs 2.8%, P = 0.073).

Conclusion

Over one-third of outpatients with stable moderate to very severe COPD had a suboptimal PIF against a medium low resistance DPI. The phenotype of suboptimal PIF was short stature, female, and Black. Suboptimal PIF status was associated with shorter time to moderate/severe COPD exacerbations compared with optimal PIF.

Experimental Evaluation of Dry Powder Inhalers during Inhalation and Exhalation Using a Model of the Human Respiratory System (xPULM™)

Dry powder inhalers are used by a large number of patients worldwide to treat respiratory diseases. The objective of this work is to experimentally investigate changes in aerosol particle diameter and particle number concentration of pharmaceutical aerosols generated by four dry powder inhalers under realistic inhalation and exhalation conditions. To simulate patients undergoing inhalation therapy, the active respiratory system model (xPULM™) was used. A mechanical upper airway model was developed, manufactured, and introduced as a part of the xPULM™ to represent the human upper respiratory tract with high fidelity. Integration of optical aerosol spectrometry technique into the setup allowed for evaluation of pharmaceutical aerosols. The results show that there is a significant difference (p < 0.05) in mean particle diameter between inhaled and exhaled particles with the majority of the particles depositing in the lung, while particles with the size of (>0.5 μm) are least influenced by deposition mechanisms. The fraction of exhaled particles ranges from 2.13% (HandiHaler®) over 2.94% (BreezHaler®), and 6.22% (Turbohaler®) to 10.24% (Ellipta®). These values are comparable to previously published studies. Furthermore, the mechanical upper airway model increases the resistance of the overall system and acts as a filter for larger particles (>3 μm). In conclusion, the xPULM™ active respiratory system model is a viable option for studying interactions of pharmaceutical aerosols and the respiratory tract regarding applicable deposition mechanisms. The model strives to support the reduction of animal experimentation in aerosol research and provides an alternative to experiments with human subjects.

Relationship between Peak Inspiratory Flow and Patient and Disease Characteristics in Individuals with COPD—A Systematic Scoping Review

Optimal delivery of medication via dry powder inhalers, the most commonly prescribed inhaler type, is dependent on a patient achieving a minimum level of inspiratory flow during inhalation. However, measurement of peak inspiratory flow (PIF) against the simulated resistance of a dry powder inhaler is not frequently performed in clinical practice due to time or equipment limitations. Therefore, defining which patient characteristics are associated with lower PIF is critically important to help clinicians optimize their inhaler choice through a more personalized approach to prescribing. The objective of this scoping review was to systematically evaluate patient and disease characteristics determining PIF in patients with chronic obstructive pulmonary disease (COPD). Medline, Cochrane and Embase databases were systematically searched for relevant studies on PIF in patients with COPD published in English between January 2000 and May 2021. The quality of evidence was assessed using a modified Grading of Recommendations Assessment, Development and Evaluation checklist. Of 3382 citations retrieved, 35 publications were included in the review (nine scored as high quality, 13 as moderate, nine as low, and four as very low). Factors correlating with PIF in >70% of papers included both patient characteristics (lower PIF correlated with increased age, female gender, shorter height, decreased handgrip and inspiratory muscle strength, and certain comorbidities) and disease characteristics (lower PIF correlated with markers of lung hyperinflation, lower peak expiratory flow [PEF] and increased disease severity). Other factors correlating with adequate/optimal or improved PIF included education/counseling and exercise/inspiratory muscle training; impaired physical function and errors in inhalation technique/non-adherence were associated with low/suboptimal PIF. In conclusion, clinicians should measure PIF against the simulated resistance of a particular device wherever possible. However, as this often cannot be done due to lack of resources or time, the patient and disease characteristics that influence PIF, as identified in this review, can help clinicians to choose the most appropriate inhaler type for their patients.

Measuring Peak Inspiratory Flow in Patients with Chronic Obstructive Pulmonary Disease

Dry powder inhalers (DPIs) are breath actuated, and patients using DPIs need to generate an optimal inspiratory flow during the inhalation maneuver for effective drug delivery to the lungs. However, practical and standardized recommendations for measuring peak inspiratory flow (PIF)—a potential indicator for effective DPI use in chronic obstructive pulmonary disease (COPD)—are lacking. To evaluate recommended PIF assessment approaches, we reviewed the Instructions for Use of the In-Check™ DIAL and the prescribing information for eight DPIs approved for use in the treatment of COPD in the United States. To evaluate applied PIF assessment approaches, we conducted a PubMed search from inception to August 31, 2021, for reports of clinical and real-life studies where PIF was measured using the In-Check™ DIAL or through a DPI in patients with COPD. Evaluation of collective sources, including 47 applicable studies, showed that instructions related to the positioning of the patient with their DPI, instructions for exhalation before the inhalation maneuver, the inhalation maneuver itself, and post-inhalation breath-hold times varied, and in many instances, appeared vague and/or incomplete. We observed considerable variation in how PIF was measured in clinical and real-life studies, underscoring the need for a standardized method of PIF measurement. Standardization of technique will facilitate comparisons among studies. Based on these findings and our clinical and research experience, we propose specific recommendations for PIF measurement to standardize the process and better ensure accurate and reliable PIF values in clinical trials and in daily clinical practice.

Managing hospitalized patients with a COPD exacerbation: the role of hospitalists and the multidisciplinary team

Exacerbations of chronic obstructive pulmonary disease (COPD) are associated with high rates of hospitalizations, costs, and morbidity. Therefore, hospitalists and the multidisciplinary team (hospital team) need to take a proactive approach to ensure patients are effectively managed from hospital admission to postdischarge. Comprehensive screening and diagnostic testing of patients at admission will enable an accurate diagnosis of COPD exacerbations, and severity, as well as other factors that may impact the length of hospital stay. Depending on the exacerbation severity and cause, pharmacotherapies may include short-acting bronchodilators, systemic corticosteroids, and antibiotics. Oxygen and/or ventilatory support may benefit patients with demonstrable hypoxemia. In preparation for discharge, the hospital team should ensure that patients receive the appropriate maintenance therapy, are counseled on their medications including inhalation devices, and proactively discuss smoking cessation and vaccinations. For follow-up, effective communication can be achieved by transferring discharge summaries to the primary care physician via an inpatient case manager. An inpatient case manager can support both the hospitalist and the patient in scheduling follow-up appointments, sending patient reminders, and confirming that a first outpatient visit has occurred. A PubMed search (prior to 26 January 2021) was conducted using terms such as: COPD, exacerbation, hospitalization. This narrative review focuses on the challenges the hospital team encounters in achieving optimal outcomes in the management of patients with COPD exacerbations. Additionally, we propose a novel simplified algorithm that may help the hospital team to be more proactive in the diagnosis and management of patients with COPD exacerbations.

Aerosol drug-delivery and short-term clinical outcomes of suboptimal peak inspiratory flow rate in chronic obstructive pulmonary disease

AIM OF WORK

Suboptimal peak inspiratory flow rate (PIFR) is highly prevalent in chronic obstructive pulmonary disease (COPD) patients owing to the mismatch of their own PIFR with the corresponding inhaler-device resistance. This study aimed to evaluate aerosol drug-delivery and short-term clinical outcomes of suboptimal PIFR in COPD subjects.

METHODS

Twenty optimal and suboptimal COPD subjects were crossed over in this prospective, randomised, controlled, open-label study. They were tested for urinary salbutamol amount (USAL30) and spirometric response 30 min poststudy dose (200 µg salbutamol) through Aerolizer^® and Handihaler^® after assessment of their own PIFR through In-Check™ Dial G16. Urine samples were extracted through solid-phase extraction and assayed through a high performance liquid chromatography (HPLC) method.

RESULTS

Mean USAL30 was significantly higher in the optimal group than in the suboptimal group (P = .001). There was no significant difference in ΔFEV1% predicted and ΔFVC% predicted between optimal and suboptimal groups, with higher values in optimal Aerolizer^® and Handihaler^® than in suboptimal groups.

CONCLUSION

Suboptimal PIFR was associated with a significantly lower drug delivery in COPD subjects at hospital discharge, and a slightly lower pulmonary function response 30 min postbronchodilation if compared with optimal PIFR.

The Role of the Pharmacist in Inhaler Selection and Education in Chronic Obstructive Pulmonary Disease

Objective: To review the role of pharmacists in educating and monitoring patients with chronic obstructive pulmonary disease (COPD) on inhalation technique. Data Sources: A PubMed search (January 2000 to May 2020) was performed using the following keywords and associated medical subject headings: adherence, chronic obstructive pulmonary disease/COPD, education, inhaler, pharmacist, and technique. Study Selection and Data Extraction: The search was conducted to identify English language articles highlighting the importance of correct inhaler technique in COPD management and benefits of pharmacist inhaler training such as improved adherence, quality of life (QoL), and disease control. Randomized controlled trials, retrospective studies, observational studies, systematic reviews, and meta-analysis reporting pharmacist training were included. Data Synthesis: This review summarizes that incorrect inhaler use negatively affects treatment outcomes, prognosis, and QoL. Pharmacists are in a unique position to educate and monitor patients with COPD on optimal inhaler technique and an individualized, multifactorial approach to COPD management involving pharmacists could provide cost-effective patient care and improve adherence and minimize inhaler misuse. Several strategies used by pharmacists can optimize patient inhaler use, such as face-to-face technique demonstrations, the "teach-back" method, telemonitoring, instructional videos, or informational leaflets. An individualized action plan involving education and regular monitoring of inhaler use further enhances optimal adherence and disease management. Conclusions: As pharmacists are easily accessible to both patients and health care providers, they are ideally placed to play an important role in the enhancement of education on, and continuous assessment of, optimal inhaler technique, thereby improving adherence, disease control, and QoL.

Inhaler technique in asthma and COPD: challenges and unmet knowledge that can contribute to suboptimal use in real life

Introduction: Inhalers are the most commonly used devices for lung drug delivery in asthma and COPD. Inhaler use offers several advantages but requires the user's proper mastery. The issue of inhaler technique is very important as inhaler misuse remains common in real life regardless of the inhaler used and is associated with poor disease control.Areas covered:This narrative review analyses the key-steps of inhaler mastery and the significance of the errors of use for the main devices. There are uncertainties on many tasks of inhaler use and on those variations from recommended steps that are considered as critical errors.Expert opinion: Despite technological advancements, an easy-to-use device is not yet available. Whatever the chosen inhaler, health care givers' proper practical education with the opportunity of feedback learning has a key-role for improving inhaler technique, but is time-consuming, and remains limited to few successful experiences. Newer digital technologies will be applied to the field of inhaler education, but the lack of knowledge on many practical aspects of inhaler technique might be a limit for its extensive implementation. Possibly digital innovation might substantially contribute to reduce inhaler misuse only if clinicians, manufacturers, and subjects will cooperate together on this issue.

Peak-Inspiratory-Flow-Rate Guided Inhalation Therapy Reduce Severe Exacerbation of COPD

Optimal peak inspiratory flow rate (PIFR) is crucial for inhalation therapy in patients with chronic obstructive pulmonary disease (COPD). However, little is known about the impact of PIFR-guided inhalation therapy on the clinical outcomes among patients with varying severities of COPD. A PIFR-guided inhalation therapy, including PIFR assessment and PIFR-guided inhaler education, was introduced in a pay-for-performance COPD management program in National Taiwan University Hospital. Among 383 COPD patients, there was significant reduction in incidence of severe acute exacerbation in the PIFR-guided inhalation therapy (PIFR group) than conventional inhaler education (control group) (11.9 vs. 21.1%, p = 0.019) during one-year follow-up. A multivariable Cox’s proportional-hazards analysis revealed that the PIFR-guided inhalation therapy was a significant, independent factor associated with the reduced risk of severe exacerbation (adjusted hazard ratio = 0.49, 95% confidence interval, 0.28–0.84, p = 0.011). Subgroup analysis found PIFR-guided inhalation therapy was more beneficial to patients with older age, short body stature, COPD stage 1&2, group C&D (frequent exacerbation phenotype), and using multiple inhalers. This study showed the PIFR-guided inhalation therapy significantly reduced the incidence of severe acute exacerbation than conventional inhaler education in patients with COPD. Careful PIFR-assessment and education would be crucial in the management of COPD.

Inspiratory flow patterns with dry powder inhalers of low and medium flow resistance in patients with pulmonary arterial hypertension

Inhalation profiles to support use of dry powder inhalers for drug delivery in patients with pulmonary arterial hypertension have not been reported. We aimed to evaluate the inspiratory flow pattern associated with low and medium flow resistance dry powder inhaler devices (RS01-L and RS01-M, respectively) in patients with pulmonary arterial hypertension. This single-center study enrolled patients with pulmonary arterial hypertension associated with connective tissue disease (n = 10) and idiopathic pulmonary arterial hypertension (n = 10) to measure the following inhalation parameters: inspiratory effort (kPa), peak inspiratory flow rate (L/min), inhaled volume (L), and flow increase rate (L/s²) using the two devices. We identified a trend toward higher mean pulmonary artery pressure in the idiopathic pulmonary arterial hypertension group (50 ± 13 mmHg vs. 40 ± 11 mmHg in pulmonary arterial hypertension associated with connective tissue disease; p = 0.077). On average, peak inspiratory flow rate was higher with RS01-L vs. RS01-M (84 ± 19.7 L/min vs. 70.4 ± 13.2 L/min; p = 0.015). In the overall group, no differences between RS01-L and RS01-M were observed for inhaled volume, inspiratory effort, or flow increase rate. Inhaled volume with RS01-L was higher in pulmonary arterial hypertension associated with connective tissue disease vs. idiopathic pulmonary arterial hypertension patients: 1.6 ± 0.4 L vs. 1.3 ± 0.2 L; p = 0.042. For the RS01-L, inhaled volume correlated with forced expiratory volume in one second (r = 0.460, p = 0.030) and forced vital capacity (r = 0.507, p = 0.015). In patients with pulmonary arterial hypertension associated with connective tissue disease using RS01-L, both inspiratory effort and flow increase rate were highly correlated with pulmonary vascular compliance (r = 0.903, p = 0.0001 and r = 0.906, p = 0.0001; respectively); while with RS01-M, inspiratory effort was highly correlated with pulmonary vascular compliance (r = 0.8, p = 0.001). Our data suggest that the use of RS01-L and RS01-M dry powder inhaler devices allowed adequate inspiratory flow in pulmonary arterial hypertension patients. The correlation between flow increase rate and pulmonary vascular compliance in pulmonary arterial hypertension associated with connective tissue disease deserves further investigation.

Clinical Characterization of Nursing Facility Residents With Chronic Obstructive Pulmonary Disease

OBJECTIVE AND DESIGN

To describe clinical characteristics, medication use, and low peak inspiratory flow rate (PIFR) (< 60 L/min) prevalence in nursing facility residents with chronic obstructive pulmonary disease (COPD).

PATIENTS AND SETTING

Residents 60 years of age and older with a COPD diagnosis and≥ 6 months' nursing facility residence, were enrolled between December 2017 and February 2019 from 26 geographically varied United States nursing facilities.

OUTCOME MEASURES

Data, extracted from residents' charts, included demographic/clinical characteristics, COPD-related medications, exacerbations and hospitalizations within the past 6 months, and functional status from the most recent Minimum Data Set. At enrollment, residents completed the modified Medical Research Council (mMRC) Dyspnea Scale and COPD Assessment Test (CAT™). Spirometry and PIFR were also assessed.

RESULTS

Residents' (N = 179) mean age was 78.0 ± 10.6 years, 63.7% were female, and 57.0% had low PIFR. Most prevalent comorbidities were hypertension (79.9%), depression (49.2%), and heart failure (41.9%). The average forced expiratory volume in 1 second (FEV1₁) % predicted was 45.9% ± 20.9%. On the CAT, 78.2% scored≥ 10 and on the mMRC Dyspnea Scale, 74.1% scored≥ 2, indicating most residents had high COPD symptom burden. Only 49.2% were receiving a scheduled long-acting bronchodilator (LABD). Among those with low PIFR prescribed a LABD, > 80% used dry powder inhalers for medication delivery.

CONCLUSION

This study highlights underutilization of scheduled LABD therapy in nursing facility residents with COPD. Low PIFR was prevalent in residents while the majority used suboptimal medication delivery devices. The findings highlight opportunities for improving management and outcomes for nursing facility residents with COPD.

Lung Deposition and Inspiratory Flow Rate in Patients with Chronic Obstructive Pulmonary Disease Using Different Inhalation Devices: A Systematic Literature Review and Expert Opinion

BACKGROUND

Our aim was to describe: 1) lung deposition and inspiratory flow rate; 2) main characteristics of inhaler devices in chronic obstructive pulmonary disease (COPD).

METHODS

A systematic literature review (SLR) was conducted to analyze the features and results of inhaler devices in COPD patients. These devices included pressurized metered-dose inhalers (pMDIs), dry powder inhalers (DPIs), and a soft mist inhaler (SMI). Inclusion and exclusion criteria were established, as well as search strategies (Medline, Embase, and the Cochrane Library up to April 2019). In vitro and in vivo studies were included. Two reviewers selected articles, collected and analyzed data independently. Narrative searches complemented the SLR. We discussed the results of the reviews in a nominal group meeting and agreed on various general principles and recommendations.

RESULTS

The SLR included 71 articles, some were of low-moderate quality, and there was great variability regarding populations and outcomes. Lung deposition rates varied across devices: 8%-53% for pMDIs, 7%-69% for DPIs, and 39%-67% for the SMI. The aerosol exit velocity was high with pMDIs (more than 3 m/s), while it is much slower (0.84-0.72 m/s) with the SMI. In general, pMDIs produce large-sized particles (1.22-8 μm), DPIs produce medium-sized particles (1.8-4.8 µm), and 60% of the particles reach an aerodynamic diameter <5 μm with the SMI. All inhalation devices reach central and peripheral lung regions, but the SMI distribution pattern might be better compared with pMDIs. DPIs' intrinsic resistance is higher than that of pMDIs and SMI, which are relatively similar and low. Depending on the DPI, the minimum flow inspiratory rate required was 30 L/min. pMDIs and SMI did not require a high inspiratory flow rate.

CONCLUSION

Lung deposition and inspiratory flow rate are key factors when selecting an inhalation device in COPD patients.

The contribution of patients' lung function to the inspiratory airflow rate achievable through a DPIs' simulator reproducing different intrinsic resistance rates

Background

The performance of DPIs depends on several physiological (patient-dependent) and technological (device-dependent) factors. The inspiratory airflow rate is the only active force generated and operating in the system for inducing the required pressure drop and eliciting the resistance-induced turbulence needed to disaggregate the powder through the device. The present study aimed to investigate in the most prevalent respiratory disorders whether and at what extent the inspiratory airflow rate achievable when inhaling through a DPIs’ simulator reproducing different intrinsic resistance regimens (low, mid, and high resistance) is affected by peculiar changes in lung function and/or can be predicted by any specific lung function parameter.

Methods

The inspiratory airflow rate was assessed in randomized order by the In-Check DIAL G16 at low, mid, and high resistance regimens in a sample of consecutive subjects at recruitment. Independent predictors of the probability to achieve the expected inhalation airflow rate were investigated by means of a multivariate logistic regression model, specific to the disease.

Results

A total of 114 subjects were recruited (asthmatics n=30; COPD n=50, restrictive patients n=16, and normal subjects n=18). The mean values of the expected inspiratory airflow rate achieved proved significantly different within the groups (p<0.0001), independently of sex and age. In asthmatics and in COPD patients, the mid-resistance regimen proved highly associated with the highest mean values of airflow rates obtained. Low- and high-resistance regimens were significantly less likely to consent to achieve the expected level of inspiratory airflow rate (OR<1 in all comparisons). Restrictive patients performed the lowest airflow rates at the low-resistance regimen (p<0.01). Unlike FEV¹, RV in asthmatics (OR=1.008); RV and I_Raw in COPD (OR=0.587 and OR=0.901, respectively), and FIF and TLC in restrictive patients (OR=1.041, and OR=0.962, respectively) proved the only sensitive predictors of the inspiratory airflow rate achievable at the different resistive regimens.

Conclusions

The intrinsic resistive regimen of DPIs can play a critical role. The patients’ lung function profile also affects the extent of their inhalation airflow rate. Some specific lung function parameters (such as: FIF; RV; I_Raw; TLC, but not FEV₁) may be regarded as specific predictors in real-life. In order to optimize the DPI choice, further to the device’s technology, also the current patients’ lung function should be properly investigated and carefully assessed.

Peak Inspiratory Flow as a Predictive Therapeutic Biomarker in COPD

Biomarkers in COPD may be clinical (prior exacerbation history), physiologic (FEV₁), or blood based (eosinophil count or fibrinogen level). Recent interest in using biomarkers to predict response to therapy in clinical practice has emerged. The benefits of inhaled therapy depend on the correct use of the inhaler, including an appropriate inspiratory flow. Of the available delivery systems, dry powder inhalers are unique because they have an internal resistance, are breath actuated, and are flow dependent. Ideally, the user inhales "forcefully" to generate turbulent energy (determined by an individual's inspiratory flow and the resistance of the device) within the device that disaggregates the powder so that the individual inhales the medication particles into the lower respiratory tract. Because of specific features of dry powder inhalers and the required optimal inspiratory flow, an unmet need exists to identify individuals who are likely or unlikely to benefit from dry powder medications. Peak inspiratory flow, defined as the maximum airflow generated during inhalation against the simulated resistance of a dry powder inhaler, is a physiologic measure that has biological plausibility, has good test characteristics (repeatability and reliability), and is generalizable. Current evidence supports peak inspiratory flow as a predictive therapeutic biomarker to optimize therapy in both outpatients with COPD as well as those hospitalized for an exacerbation before discharge. This approach is consistent with the precepts of precision medicine, which considers differences in a person's biological features, exposure, and lifestyle to prevent and treat disease.

The emerging role of nebulization for maintenance treatment of chronic obstructive pulmonary disease at home

Inhalation therapy is the cornerstone of chronic obstructive pulmonary disease (COPD) management. However, for many COPD patients who are managed at home, nebulization therapy offers an effective alternative treatment and fulfills the gap of catering to the specific population of patients who are unable to use handheld inhaler devices appropriately. The present review highlights key aspects, namely selection of the right beneficiaries for home nebulization, available drugs in nebulized formulations for the treatment of COPD, and the importance of care, cleaning, and maintenance, which are prerequisites for ensuring successful nebulization therapy.

Evaluation of Suboptimal Peak Inspiratory Flow in Patients with Stable COPD

Objective: Although the importance of assessing inspiratory flow in the selection of treatments for chronic obstructive pulmonary disease (COPD) is understood, evaluation of this factor is not yet widespread or standardized. The objective of the present work was to evaluate the peak inspiratory flow (PIF) of patients with COPD and to explore the variables associated with a suboptimal PIF. Methods: An observational, cross-sectional study was carried out at specialized nursing consultations over a period of 6 months. We collected clinical data as well as data on symptoms, treatment adherence, and patient satisfaction with their inhalers via questionnaires. PIF was determined using the In-Check Dial G16^® device (Clement Clarke International, Ltd., Harlow, UK). In each case, the PIF was considered suboptimal when it was off-target for any of the prescribed inhalers. The association with suboptimal PIF was evaluated using multivariate logistic regression and the results were expressed as the odds ratio (OR) with 95% confidence interval (CI). Results: A total of 122 COPD patients were included in this study, of whom 34 (27.9%) had suboptimal PIF. A total of 229 inhalers were tested, of which 186 (81.2%) were dry powder devices. The multivariate analysis found an association between suboptimal PIF and age (OR = 1.072; 95% CI (1.019, 1.128); p = 0.007) and forced vital capacity (OR = 0.961; 95% CI (0.933, 0.989); p = 0.006). Conclusions: About a third of patients in complex specialized COPD care have suboptimal PIFs, which is related to age and forced vital capacity.

Switching Inhalers: A Practical Approach to Keep on UR RADAR

The choice of an inhaler device is often as important as the medication put in it to achieve optimal outcomes for our patients with asthma and/or COPD. With a multitude of drug–device combinations available, optimization of respiratory treatment could well be established by switching devices rather than changing or even augmenting pharmacological or non-pharmacological therapies. Importantly, while notable between-device differences in release mechanism, particle size, drug deposition and required inspiratory flow exist, a patient uncomfortable with their device is unlikely to use it regularly and certainly will not use it properly. Switching requires a careful process and should not be done without patient consent. Switching devices entails several steps that need to be considered, which can be guided using the UR-RADAR mnemonic. It starts with (i) UncontRolled asthma/COPD (or UnaffoRdable device), followed by RADAR: (ii) review the patient’s condition (e.g. diagnosis, phenotype, co-morbidities) and address reasons for suboptimal control (e.g. triggers, smoking, non-adherence, poor inhaler technique) to be ruled out before switching; (iii) assess patient’s skills related to inhalation (e.g. inspiratory force); (iv) discuss inhaler switch options, patient preferences (e.g. size, daily regimen) and treatment goals; (v) allow patients input and use shared decision-making to decide final treatment choice, acknowledging individual patient skills, preferences and goals; and (vi) re-educate to the new device (at minimum, physical demonstration, verbal explanation and patient repetition, both verbally and physically) and prime the patient for the follow-up (i.e. explain the future patient journey, including multidisciplinary work flows with physicians, nurses and pharmacists).

Choosing the right inhaler for the right patient: Considerations for effective management of patients with chronic obstructive pulmonary disease or asthma

BACKGROUND AND PURPOSE

Effective management of chronic respiratory disorders such as chronic obstructive pulmonary disease and asthma necessitates that patients inhale their medication. However, lack of detailed guidelines on the technological and mechanical functions of inhalers limits the ability of health care providers (HCPs) to personalize inhaler choice for patients. Numerous types of inhalers are currently available which offer their own distinct advantages and disadvantages. Independent of the drug class, the choice of inhaler may be influenced by many factors (e.g., inhaler attributes and the efficiency with which it delivers the medication, patient characteristics and preferences, dosing regimen, clinical setting, and support available for both patients and HCPs). This article attempts to summarize the inhalation technology and factors influencing inhaler choice and use and to provide an approach for matching the right inhaler to the right patient.

CONCLUSIONS

Identifying factors related to inhaler choice is critical to ensuring adherence to treatment and patients' ability to use their inhaler correctly.

IMPLICATIONS FOR PRACTICE

This review will help HCPs engage their patients in decision-making for inhaler choice and facilitate selection of the correct inhaler for each patient (i.e., one that they will use).

Nebulized Therapies in COPD: Past, Present, and the Future

Current guidelines recommend inhalation therapy as the preferred route of drug administration for treating patients with chronic obstructive pulmonary disease (COPD). Inhalation devices consist of nebulizers and handheld inhalers, such as dry-powder inhalers (DPIs), pressurized metered-dose inhalers (pMDIs), and soft mist inhalers (SMIs). Although pMDIs, DPIs and SMIs may be appropriate for most patients with COPD, certain patient populations may have challenges with these devices. Patients who have cognitive, neuromuscular, or ventilatory impairments (and receive limited assistance from caregivers), as well as those with suboptimal peak inspiratory flow may not derive the full benefit from handheld inhalers. A considerable number of patients are not capable of producing a peak inspiratory flow rate to overcome the internal resistance of DPIs. Furthermore, patients may have difficulty coordinating inhalation with device actuation, which is required for pMDIs and SMIs. However, inhalation devices such as spacers and valved holding chambers can be used with pMDIs to increase the efficiency of aerosol delivery. Nebulized treatment provides patients with COPD an alternative administration route that avoids the need for inspiratory flow, manual dexterity, or complex hand-breath coordination. The recent approval of two nebulized long-acting muscarinic antagonists has added to the extensive range of nebulized therapies in COPD. Furthermore, with the availability of quieter and more portable nebulizer devices, nebulization may be a useful treatment option in the management of certain patient populations with COPD. The aim of this narrative review was to highlight recent updates and the treatment landscape in nebulized therapy and COPD. We first discuss the pathophysiology of patients with COPD and inhalation device considerations. Second, we review the updates on recently approved and newly marketed nebulized treatments, nebulized treatments currently in development, and technological advances in nebulizer devices. Finally, we discuss the current applications of nebulized therapy in patients with COPD.

Effect of PIFR-based optimised inhalation therapy in patients recovering from acute exacerbation of chronic obstructive pulmonary disease: protocol of a prospective, multicentre, superiority, randomised controlled trial

INTRODUCTION

Acute exacerbation (AE) is a major cause of disease progression and death in patients with chronic obstructive pulmonary disease (COPD), accounting for majority of medical expenditures. Correct inhalation therapy is effective in preventing AE attacks. However, inappropriate usage of dry powder inhaler, partially due to the unrecovered peak inhalation flow rate (PIFR) after acute exacerbation of COPD (AECOPD), results in increased risk of early treatment failure. Therefore, we designed a multicentre, randomised clinical trial to determine whether PIFR-based optimised inhalation therapy and training on inhaler usage at discharge could effectively reduce early treatment failure events.

METHODS AND ANALYSIS

A total of 416 hospitalised patients just recovering from AECOPD will be recruited and equally randomised into the PIFR group and the control group at a 1:1 ratio. The PIFR group will receive additive support before discharge, including choice of PIFR-guided inhaler and education on its usage. PIFR is measured by InCheck DIAL. In comparison, the control group will receive inhalers based on judgement of the respiratory physician. The primary outcome of the study is 30-day treatment failure rate. Other endpoints include PIFR, error rate of inhalation device use, satisfaction with inhalation devices, 30-day mortality, 90-day mortality, symptoms and quality of life of patients, and COPD-related treatment costs.

ETHICS AND DISSEMINATION

The trial has been approved by the Ethics Committee of Zhongshan Hospital of Fudan University (B2019-142). Participants will be screened and enrolled from hospitalised patients with AECOPD by clinicians, with no public advertisement for recruitment. After the trial has completed, the results will be reported to the public through conference presentations and peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04000958.

Inappropriate Peak Inspiratory Flow Rate with Dry Powder Inhaler in Chronic Obstructive Pulmonary Disease

Optimal peak inspiratory flow rate (PIFR) is crucial for optimizing dry powder inhaler (DPI) effectiveness for chronic obstructive pulmonary disease (COPD). This study provide an insight that there was a substantial proportion of improper PIFRs (not only insufficient but also excessive) among COPD patients using DPIs. We enrolled 138 COPD patients from a medical center in Taiwan and measured PIFRs against different internal resistances of DPIs. Proportion of excessive, optimal, suboptimal, and insufficient PIFRs were 2%, 54%, 41%, 3%, respectively, against medium-high resistance; 2%, 77%, 20%, 1%, respectively, against medium resistance; 27%, 63%, 9%, 1%, respectively, against medium-low resistance; and 42%, 57%, 1%, 0%, respectively, against low resistance (p < 0.01). Although most PIFRs against medium-high (54%), medium (77%), medium-low (63%) and low (57%) resistance were optimal, a substantial proportion of PIFRs against low resistance were excessive (42%, p < 0.01), irrespective of age, body-mass index, dyspnea severity score, and COPD severity. Insufficient PIFRs were infrequent, but suboptimal/insufficient PIFRs were most prevalent in patients older than 75 years than in younger patients (36% vs. 56%, p = 0.036) against medium-high resistance. Regularly monitoring PIFRs against the specific resistance of the DPIs and instructing patients to employ a proper inspiration effort may help to optimize the effects of DPIs.

Peak Inspiratory Flows: Defining Repeatability Limits and a Predictive Equation for Different Inhalers

BACKGROUND

Peak inspiratory flow (PIF) has been proposed as a measure to assess a patient's ability to use dry powder inhalers (DPIs). However, robust quality criteria to determine a repeatability limit for measuring PIF are lacking.

RESEARCH QUESTIONS

What are the repeatability limits for measuring PIF? What is the relationship between PIF measured using the In-Check DIAL device at Diskus (GlaxoSmithKline; PIF_D) and HandiHaler (Boehringer Ingelheim; PIF_HH) resistances?

STUDY DESIGN AND METHODS

Data from a randomized, controlled, phase 3 trial (study 0149; see Clinical Trial Registration data) were used to define repeatability limits for PIF. In addition, a model to characterize the relationship between PIF measured with the In-Check DIAL device at PIF_D and PIF_HH was defined using data from two randomized, controlled, phase 3 trials (studies 0128 and 0149).

RESULTS

In study 0128, the mean values (SD) for PIF at zero resistance and PIF_HH were 84.6 (33.4) and 57.3 (26.1) L/min, respectively. In study 0149, the mean values (SD) for PIF_D and PIF_HH were 42.4 (11.2) and 29.0 (8.3) L/min, respectively. At the mean level, the mean difference between measurement attempts for PIF_D and PIF_HH was small, < 5 and < 3 L/min, respectively. The repeatability limit was determined as 10 and 5 L/min for PIF_D and PIF_HH, respectively. Modeling the relationship between PIF_D and PIF_HH, after controlling for significant covariates, demonstrated that a PIF_D value of 60 L/min was approximately equivalent to PIF_HH of 40 L/min.

INTERPRETATIONS

This analysis demonstrated that the two highest values of PIF using the In-Check DIAL device among three inspiratory efforts, met the repeatability limit. Altogether, these data provide guidance for measuring PIF against the simulated resistance of a specific DPI in clinical practice and research studies.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov; Nos.: NCT02518139 (study 0128) and NCT03095456 (study 0149); URL: www.clinicaltrials.gov.

Prevalence and predictors of suboptimal peak inspiratory flow rate in COPD patients

The aim of this study was to determine prevalence and possible clinical predictors of suboptimal peak inspiratory flow rate (PIFR) with different dry powder inhalers. PIFR was measured across all resistance ranges of In-Check Dial® in 180 chronic obstructive pulmonary disease (COPD) subjects before hospital discharge. COPD subjects were defined as suboptimal if measured PIFR was suboptimal with any resistance representative of specific inhalers (R1-R5). Demographics and clinical data were collected, including COPD Assessment Test (CAT) and modified Medical Research Council (mMRC) scores, Global Initiative for Obstructive Lung Disease (GOLD) stage spirometry by Spirodoc® and peak flow meter measurements with portable peak inspiratory and expiratory flow meters. All were correlated with In-Check Dial PIFRs. Suboptimal PIFR was 44.44% prevalent in COPD subjects. 55% of the suboptimal cohort was female which represent 57.14% of the total female population in the study. The distribution of suboptimal PIFR included 43.75% with R1, 67.5% with R2, 100% with R3, 13.75% with R4, and 21.25% with R5. In the suboptimal cohort, CAT score was significantly higher and spirometry demonstrated significantly lower lung function results compared to the optimal cohort (p < 0.05). The only parameter to show strong and moderate correlation with In-Check Dial PIFRs was PIFR measured by peak flow meter (p < 0.001). Suboptimal PIFR is common among COPD subjects at hospital discharge. Female gender and peak flow meter PIFR was the only predictor of suboptimal PIFR. Inhaler therapy for COPD patients must be personalized based on simple routine measurement of In-Check Dial PIFRs or peak flow meter PIFR to optimize clinical benefits .

Trends and Factors Associated with Nebulized Therapy Prescription in Older Adults with Chronic Obstructive Pulmonary Disease from 2008 to 2015

Background: Medical management of patients with chronic obstructive pulmonary disease (COPD) includes nebulized therapy as an option for inhalational drug delivery. A broad variety of short- and long-acting bronchodilators and inhaled corticosteroids in the nebulized form are available. Despite this, limited information exists on the pattern and predictors of nebulized prescription. We examined the trend and factors associated with prescription of nebulized therapy among Medicare beneficiaries with COPD. Methods: A retrospective cross-sectional study of 5% Medicare beneficiaries with COPD (n = 66,032) who were enrolled in parts A, B, and D and received nebulized prescription from 2008 to 2015 was conducted. This sample has shown to be representative of the entire fee-for-service Medicare population. The primary outcome was a prescription of nebulized medications. Reliever nebulized medications included short-acting beta agonist (SABA), short-acting muscarinic agents (SAMAs), and a combination of SABA and SAMA, while maintenance nebulized medications included long-acting beta agonists, long-acting muscarinic agents, and corticosteroid solutions as well as combinations of these agents. The secondary outcome was prescription of other inhaler respiratory medications not administered with a nebulizer. Results: Overall, 38.9% patients were prescribed nebulized medication and their prescription significantly declined from 42.4% in 2008 to 35.1% in 2015, majority of which was related to decreased prescriptions of nebulized relievers. Factors associated with the prescription of nebulized medications include female gender (odds ratio [OR] = 1.06; 95% confidence interval [CI] = 1.02-1.09), dual eligibility or low-income subsidy beneficiaries (OR = 1.49; CI = 1.44-1.53), hospitalization for COPD in the previous year (OR = 1.29; CI = 1.25-1.34), home oxygen therapy (OR = 2.29; CI = 2.23-2.36), pulmonary specialist visit (OR = 1.24; CI = 1.20-1.27), and moderate (OR = 1.61; CI = 1.57-1.65) or high (OR = 1.52; CI = 1.46-1.59) severity of COPD. Conclusion: Between 2008 and 2015, prescriptions for nebulized therapy for COPD declined among Medicare beneficiaries, probably related to increase in use of maintenance non-nebulized medications.

Association between peak inspiratory flow rate and hand grip muscle strength in hospitalized patients with acute exacerbation of chronic obstructive pulmonary disease

Rationale

Ineffective peak inspiratory flow rate (PIFR) generation in patients using inhalers results in insufficient drug delivery to the lungs and poor clinical outcomes. Low inspiratory muscle strength is associated with suboptimal PIFR.

Objective

To examine in a prospective study the relationship between PIFR and skeletal muscle strength using hand grip strength (HGS) as a surrogate.

Methods

Adult patients admitted with acute exacerbation of chronic obstructive pulmonary disease (COPD) were enrolled. PIFR was measured within 48 hours before discharge. PIFR below 60L/min was considered suboptimal. HGS was measured using a handheld dynamometer. Any readmissions and emergency department visit data were collected. The associations between PIFR, HGS, 30 and 90-day COPD and all-cause readmissions were examined, without and with adjustment for age, race and gender.

Results

Of the 75 enrolled patients, 56% had suboptimal PIFR; they were older (63.9±9.7 vs. 58.2±7.7 years) and had significantly lower HGS (24.2±11.1 vs. 30.9±10.9 Kg) compared to those with optimal PIFR. There were no significant differences between the two PIFR groups by gender, race, history of coronary artery disease, congestive heart failure, hypertension or functional scores. Each kilogram increase in HGS was associated with 0.50 (95%CI 0.18–0.89, p = 0.003) L/min increase in PIFR. We did not observe an association between PIFR and 30 or 90-day readmission rates.

Conclusion

We found a significant association between HGS and PIFR in hospitalized patients with acute exacerbations of COPD. Whether interventions aimed at increasing skeletal muscle strength also result in improvement in PIFR remains unclear and need further study.

The Impact of a Forced Non-Medical Switch of Inhaled Respiratory Medication Among Patients with Asthma or Chronic Obstructive Pulmonary Disease: A Patient Survey on Experience with Switch, Therapy Satisfaction, and Disease Control

PURPOSE

Budesonide/formoterol pressurized metered-dose inhaler (pMDI) was removed from a Medicare Part D formulary, and patients switched to fluticasone-based dry powder inhaler (DPI) therapies. This study describes the experience, satisfaction, and disease control among patients with asthma or chronic obstructive pulmonary disease (COPD) who switched due to removal from the formulary.

PATIENTS AND METHODS

A patient survey was conducted among adults with asthma or COPD who used budesonide/formoterol pMDI for ≥3 months prior to the formulary block and the new medication for ≥3 weeks after switching, recruited by providers in a research panel. Survey comprised both validated instruments (PASAPQ, OEQ, ACQ-6, and CAT) and stand-alone questions. Patient characteristics, switch experience, device and treatment satisfaction, onset of effect, and disease control were compared between disease (asthma and COPD) and medication (once and twice daily) cohorts. Minimal significance for group differences: P≤0.05.

RESULTS

Among 100 patients, 93% received communication from their doctor or nurse about the switch and 73% received training on using the new inhaler. Patients used their new treatment for an average of 7 months prior to completing the survey. Patient satisfaction with the new therapy was high (PASAPQ; mean overall satisfaction: 6.2 for asthma; 6.0 for COPD; P=0.338). However, asthma was not well controlled (ACQ-6) in 62% of patients with asthma, and 56% of patients with COPD reported high/very high impact of their illness on their lives (CAT). Sixty-eight percent and 70% of patients with asthma and COPD, respectively, required reliever medication (≥3 puffs) most days during the week prior to the survey. There were no significant differences in disease control (ACQ-6, CAT) between once-daily and twice-daily treatments (P>0.05 for both asthma and COPD).

CONCLUSION

Even when reporting satisfaction with their new medication, objective measures showed substantial morbidity, regardless of DPI device or dosing regimen.

The role of inspiratory flow in selection and use of inhaled therapy for patients with chronic obstructive pulmonary disease

Inhalation therapy is the mainstay of chronic obstructive pulmonary disease management, and inhaler selection can have a profound impact on drug delivery and medication adherence, as well as on treatment outcomes. Although multiple delivery systems, such as pressurized metered-dose inhalers, dry powder inhalers, slow-mist inhalers, and nebulizers, are available, clinical benefits achieved by patients rely on effective delivery of the inhaled medication to the airways. Among several factors influencing drug deposition, inspiratory flow is one of the most important. Inspiratory flow impacts drug delivery and subsequent clinical efficacy, making it necessary to adequately train patients to ensure correct inhaler use. Peak inspiratory flow is the maximal airflow generated during a forced inspiratory maneuver. Health care professionals need to select the appropriate delivery system after carefully considering patient characteristics, including lung function, optimal inspiratory flow, manual dexterity, and cognitive function. Herein, the role of inspiratory flow in the selection and use of inhaled therapy in patients with COPD is reviewed.

Revefenacin for the treatment of chronic obstructive pulmonary disease

Introduction: Chronic obstructive pulmonary disease (COPD) is a progressive condition characterized by irreversible or incompletely reversible airflow limitation. Long-acting bronchodilators, including β₂ agonists (LABA) and muscarinic antagonists (LAMA), serve as the standard of care for maintenance therapy in COPD. Individualizing therapy to optimize selection of delivery device has the potential to improve medication adherence and clinical outcomes among COPD patients.Areas covered: Revefenacin (Yupelri) is the only LAMA approved for once-daily administration via standard jet nebulizer for the maintenance therapy in patients with COPD. Revefenacin has a unique biphenyl carbamate tertiary amine structure, differing from the quaternary amine structure of previously approved LAMAs. Here we summarize the available clinical data for this new agent and discuss its potential place in the treatment of COPD.Expert opinion: Based on available clinical trial data, revefenacin appears to be an effective and safe option for long-term maintenance therapy of COPD. Revefenacin offers a once-daily option for LAMA therapy for patients who prefer or require nebulized drug delivery. The availability of this agent can allow patients to combine nebulized therapies that could improve clinical outcomes in appropriately selected patients with COPD.

Revefenacin: A Once-Daily, Long-Acting Bronchodilator For Nebulized Treatment Of COPD

Bronchodilation with muscarinic antagonists, β2-agonists, and inhaled corticosteroids remains the foundation of pharmaceutical treatment for patients with stable COPD. These drugs are delivered from a variety of devices, including dry powder inhalers, pressurized metered-dose inhalers, soft-mist inhalers, or nebulizers. Nebulized delivery is often preferable in patients who are elderly, are cognitively impaired, are unable to generate sufficient inspiratory force to use their inhaler, have difficulty coordinating hand-breath activity, are too dyspneic to hold their breath for a sufficient time, and/or may be acutely ill. Revefenacin, a once-daily long-acting muscarinic antagonist for nebulization recently approved by the US FDA for the treatment of patients with COPD, was discovered and developed using "duration and lung selectivity-by-design." This strategy selected a molecule with a high lung-selective index to maximize bronchodilation and limit systemic anti-muscarinic side effects. In early-phase clinical studies, revefenacin for nebulization led to a rapid onset of bronchodilation that was sustained for 24 hrs in patients with moderate to severe COPD. Revefenacin also demonstrated minimal systemic exposure and good tolerability in these studies. Statistically and clinically significant improvements in lung function (ie, peak and/or trough FEV1) relative to placebo were observed with revefenacin in Phase III clinical trials of up to 3 months in patients with moderate to very severe COPD. Revefenacin was well tolerated in Phase III clinical trials with a low incidence of systemic antimuscarinic adverse events, which is consistent with its lung-selective design. There was no evidence of an increased risk of major cardiovascular events. Patient-reported outcome data from clinical trials indicated statistically significant improvements in several disease-specific measures. Revefenacin 175 μg for nebulization provides an effective once-daily treatment option for patients with moderate to very severe COPD who require or prefer nebulized therapy.

The Confusing World of Dry Powder Inhalers: It Is All About Inspiratory Pressures, Not Inspiratory Flow Rates

Dry powder inhalers (DPIs) all have the ability to aerosolize dry powders, but they each offer different operating mechanisms and resistances to inhaled airflow. This variety has resulted in both clinician and patient confusion concerning DPI performance, use, and effectiveness. Particularly, there is a growing misconception that a single peak inspiratory flow rate (PIFR) can determine a patient's ability to use a DPI effectively, regardless of its design or airflow resistance. For this review article, we have sifted through the relevant literature concerning DPIs, inspiratory pressures, and inspiratory flow rates to provide a comprehensive and concise discussion and recommendations for DPI use. We ultimately clarify that the controlling parameter for DPI performance is not the PIFR but the negative pressure generated by the patient's inspiratory effort. A pressure drop ∼≥1 kPa (∼10 cm H₂O) with any DPI is a reasonable threshold above which a patient should receive an adequate lung dose. Overall, we explore the underlying factors controlling inspiratory pressures, flow rates and dispensing, and dispersion characteristics of the various DPIs to clarify that inspiratory pressures, not flow rates, limit and control a patient's ability to generate sufficient flow for effective DPI use.

Randomized dose-finding study of batefenterol via dry powder inhaler in patients with COPD

Background

Batefenterol is a novel bifunctional muscarinic antagonist β₂-agonist in development for COPD. The primary objective of this randomized, double-blind, placebo-controlled, active comparator, Phase IIb study was to model the dose–response of batefenterol and select a dose for Phase III development.

Patients and methods

Patients aged ≥40 years with COPD and FEV₁ ≥30% and ≤70% predicted normal were randomized equally to batefenterol 37.5, 75, 150, 300, or 600 µg, placebo, or umeclidinium/vilanterol (UMEC/VI) 62.5/25 µg once daily. The primary and secondary endpoints were weighted-mean FEV₁ over 0–6 hours post-dose and trough FEV₁, analyzed by Bayesian and maximum likelihood estimation E_max of dose–response modeling, respectively, on day 42.

Results

In the intent-to-treat population (N=323), all batefenterol doses demonstrated statistically and clinically significant improvements from baseline vs placebo in the primary and secondary endpoints (191.1–292.8 and 182.2–244.8 mL, respectively), with a relatively flat dose–response. In the subgroup reversible to salbutamol, there were greater differences between batefenterol doses. Lung function improvements with batefenterol ≥150 µg were comparable with those with UMEC/VI. Batefenterol was well tolerated and no new safety signals were observed.

Conclusion

Batefenterol 300 µg may represent the optimal dose for Phase III studies.

Prevalence and factors associated with suboptimal peak inspiratory flow rates in COPD

Purpose

Adequate peak inspiratory flow rate (PIFR) is required for drug dispersion with dry powder inhalers (DPIs). Prevalence of PIFR discordance (suboptimal PIFR with prescribed inhalers) and factors influencing device-specific PIFR are unclear in COPD. The objective of this study was to determine the prevalence of PIFR discordance and associated clinical factors in a stable COPD population.

Patients and methods

An observational, single-center, cohort study was conducted including 66 outpatients with COPD. PIFR was measured using the In-Check™ Dial with applied resistance of prescribed inhalers. Participants were defined as discordant if measured PIFR was <30 L/min and <60 L/min for high and low–medium resistance devices, respectively, using an inspiratory effort the participant normally used with their prescribed DPI.

Results

The median age of the COPD participants was 69.4 years, 92% were white and 47% were female. A total of 48% were using low–medium resistance DPIs (Diskus^®/Ellipta^®) and 76% used high-resistance DPI (Handihaler^®). A total of 40% of COPD participants were discordant to prescribed inhalers. Female gender was the only factor consistently associated with lower PIFR. Shorter height was associated with reduced PIFR for low–medium resistance (r=0.44; P=0.01), but not high resistance (r=0.20; P=0.16). There was no correlation between PIFR by In-Check™ dial and PIFR measured by standard spirometer.

Conclusion

PIFR is reduced in stable COPD patients, with female gender being the only factor consistently associated with reduced PIFR. Discordance with prescribed inhalers was seen in 40% of COPD patients, suggesting that many COPD patients do not generate adequate inspiratory force to overcome prescribed DPIs resistance in the course of normal use.

Differences in health care outcomes between postdischarge COPD patients treated with inhaled corticosteroid/long-acting β2-agonist via dry-powder inhalers and pressurized metered-dose inhalers

Purpose

The aim of this study was to examine real-world differences in health care resource use (HRU) and costs among COPD patients in the USA treated with a dry powder inhaler (DPI) or pressurized metered-dose inhaler (pMDI) following a COPD-related hospitalization.

Methods

This retrospective analysis used the Truven MarketScan^® databases. Eligibility criteria included 1) age ≥40 years, 2) COPD diagnosis, 3) inpatient admission with a diagnosis of COPD exacerbation, 4) inhaled corticosteroid (ICS)/long-acting β₂-agonist (LABA) prescription within 10 days of hospital discharge (index date), and 5) continuous enrollment for 12 months preindex and 90 days postindex. Outcomes included pre- and postindex HRU and costs. DPI and pMDI groups were compared on postindex outcomes via multivariate models controlling for demographic and baseline characteristics.

Results

The sample included 1,960 DPI and 1,086 pMDI ICS/LABA patients. During the preindex period, pMDI patients were significantly more likely to be prescribed a short-acting β-agonist, experienced more COPD exacerbation-related hospital days, and had a greater number of pulmonologist visits compared to DPI patients (P<0.05), all suggestive of greater disease severity. However, multivariate models revealed that pMDI patients incurred 10% lower all-cause postindex costs (predicted mean costs [2016 US dollars]: $2,673 vs $2,956) and 19% lower COPD-related costs (predicted mean costs: $138 vs $169; P<0.05). Additionally, pMDI patients were 28% less likely to experience a COPD exacerbation-related hospital readmission within 60 days postdischarge compared to the DPI patients (OR: 0.72, 95% CI: 0.52–0.99, P<0.05).

Conclusion

Despite greater COPD-related HRU and costs preceding index hospitalization, US patients using a pMDI after hospital discharge incurred significantly lower all-cause and COPD-related health care costs compared with those using a DPI, in addition to a decreased likelihood of a COPD exacerbation-related hospital readmission. Results suggest that inhaler device type may influence COPD outcomes and that COPD patients may derive greater clinical benefit from treatment delivered via pMDI vs DPI.

Nebulized Versus Dry Powder Long-Acting Muscarinic Antagonist Bronchodilators in Patients With COPD and Suboptimal Peak Inspiratory Flow Rate

Background

Patients with chronic obstructive pulmonary disease (COPD) and suboptimal peak inspiratory flow rate (sPIFR) may not benefit optimally from dry powder inhalers (DPI) because of inadequate inspiratory flow. Nebulized bronchodilators may provide a better alternative. We compared bronchodilation with the long-acting muscarinic antagonist (LAMA) revefenacin for nebulization versus the DPI LAMA tiotropium, in patients with COPD and sPIFR (< 60 L/min against the resistance of Diskus®).

Methods

This was a randomized, double-blind, double-dummy, 28-day Phase 3b study in patients with COPD enrolled based on sPIFR. The primary endpoint was trough forced expiratory volume in 1 second (FEV₁) on Day 29 for revefenacin for nebulization versus tiotropium HandiHaler® DPI.

Results

We enrolled 206 patients with mean (standard deviation) age, 65 (8) years; percent predicted FEV₁, 37 (16)%; PIFR, 45 (12) L/min. In the intent-to-treat (ITT) population, revefenacin improved trough FEV₁ from baseline; however, the difference versus tiotropium was not significant (least squares [LS] mean difference [standard error], 17.0 [22.4] mL, P=0.4461). In a prespecified analysis of patients with FEV₁ < 50% predicted, revefenacin produced an LS mean difference (95% confidence interval [CI]), 49.1 (6.3-91.9) mL in trough FEV₁ and 103.5 (7.7-199.3) mL in forced vital capacity versus tiotropium. Revefenacin produced >100 mL increase in FEV₁ in 41.6% versus 34.4% of patients with tiotropium in ITT and 41.4% versus 25.7% of patients in FEV₁ < 50% predicted populations.

Conclusions

Revefenacin did not produce significant improvements in FEV1 versus tiotropium in the ITT population, but increased trough FEV₁ in patients with FEV₁ < 50% predicted and sPIFR. Clinical Trial Registration (www.Clinicaltrials.gov): Study 0149 (NCT03095456).

Spirometry Measurement of Peak Inspiratory Flow Identifies Suboptimal Use of Dry Powder Inhalers in Ambulatory Patients with COPD

Objectives

Determine the prevalence of suboptimal peak inspiratory flow rate (PIFR) and associated patient characteristics and compare PIFR measurements obtained with spirometry and In-Check DIAL^® device in ambulatory patients with COPD.

Methods

Patients underwent PIFR measurement with In-Check DIAL^® device and pulmonary function testing with calibrated equipment. Group characteristics and lung function were compared for patients with suboptimal (≤ 60 L/min) and optimal (> 60 L/min) PIFR. Receiver operating curve analysis determined the best maximal forced inspiratory flow (FIF max) value in identifying optimal PIFR by gender and height.

Results

From July 1, 2016 to January 31, 2018, a total of 303 patients with chronic obstructive pulmonary disease (COPD) had PIFR and pulmonary function measurements. Group mean age was 65.5 ± 11.3 years with equal gender distribution. Suboptimal PIFR was observed in 61 (20.1%) patients. A significant correlation was observed between PIFR and FIF max, inspiratory capacity and residual volume (RV) to total lung capacity (TLC) ratio. In the suboptimal PIFR group, mean FIF max measured by spirometry was significantly less compared with the optimal PIFR group; 178.5 ± 56.9 L/min and 263.4 ± 89.9 L/min, respectively (p<0.0001). Receiver operator curve analysis of FIF max to identify an optimal PIFR yielded an area under the curve of 0.79. Males < 65 inches had a suboptimal PIFR in 16.7 % of the male cohort, while females < 65 inches had a suboptimal PIFR in 27.4 % of the women.

Conclusions

Suboptimal PIFR was present in 1 in 5 stable patients with COPD and was more frequent in short statured females. Spirometry determined FIF max was associated with PIFR based on gender and height.

Physiological predictors Of peak inspiRatory flow using Observed lung function resultS (POROS): evaluation at discharge among patients hospitalized for a COPD exacerbation

Background

Peak inspiratory flow (PIF) as generated through the resistance of a dry powder inhaler (DPI) device is a critical patient-dependent maneuver impacting the success of DPI medication delivery. Despite its importance, it is not routinely measured in clinical practice. Little is currently known about the relationship, if any, between PIF through DPI devices, routine spirometry and disease outcomes.

Aim

The aim of this study was to identify potential predictors of PIF for different DPIs from spirometric parameters and patient characteristics and explore the association between PIF and follow-up events.

Patients and methods

A retrospective observational study at discharge among patients hospitalized for a COPD exacerbation at Attikon hospital, Athens, Greece. Spirometry was performed using an Easy on-PC™ spirometer. PIF was measured through four DPI resistances using the In-Check™ DIAL. Regression analyses were used to investigate the association between PIF through resistances and spirometric parameters obtained at discharge, comorbidities and demographic parameters.

Results

Forty-seven COPD patients (mean [±SD], age 71 [±9] years, 72% males, 51% current smokers) were included in this study. Overall, 85% and 15% were classified as GOLD (2017) groups D and C, respectively. Most prevalent comorbidities were hypertension (70%) and cardiovascular disease (53%). In the final regression model, higher PIF was significantly associated with the following: higher FEV₁ and % predicted peak expiratory flow (PEF) for Turbohaler^® (R-squared value 0.374); higher FEV₁ and diagnosis of gastroesophageal reflux disease (GERD) for Aerolizer^® (R-squared value 0.209) and higher FEV₁, younger age and diagnosis of ischemic heart disease (IHD) for Diskus^® (R-squared value 0.350). However, R-squared values for all three devices were weak (<0.4).

Conclusion

The study did not provide evidence to support the use of surrogate measurements for PIF through device resistance, which could assist in determining the appropriateness of inhaler device type. Although PIF measurement is feasible in patients at discharge and could be a valuable addition to the standard of care in COPD management, it needs to be measured directly.