Assessing drug deposition efficacies, environmental impact and affordability for inhalers among chronic respiratory diseases: A systematic review
Authors: Wasnik Rahul Naresh , Cope Matthew , Cowan Aaron , Pakhale Smita 
Published: June 2024

ABSTRACTIntroductionChronic respiratory diseases such as asthma, COPD, and other pulmonary conditions impose a substantial global health burden, affecting millions of individuals worldwide. These conditions are characterized by persistent respiratory symptoms and reduced airflow, significantly impacting quality of life, and increasing healthcare needs. Treatment typically involves the use of inhaler devices to administer medications directly to the lungs, which decreases symptoms and improves outcomes. However, the efficacy of inhaler devices is influenced by various factors, including the type of device, patient adherence, and the correct device usage by patients.In addition to clinical considerations, the environmental impact of inhaler devices, including their carbon footprint, as well as the cost implications for both healthcare systems and patients, are critical factors that require comprehensive evaluation. It is essential to develop sustainable and economically viable treatment strategies that address these considerations.Methods and AnalysisWe will conduct a systematic review aimed at providing a comprehensive understanding of the implications of inhaler use in treating asthma, COPD, and other chronic conditions requiring pulmonary drug delivery. Our focus will be on assessing efficiency, environmental sustainability, and cost-effectiveness. Studies lacking economic models or evaluations, without in-vivo deposition in the lungs, lacking assessment of the environmental impact of inhalers, not published in English, or falling into categories such as systematic reviews, letters, editorials, animal studies, or case studies will be excluded from this review.The primary outcome of interest in this systematic review is the efficacy of medication deposition in the lungs of individuals with respiratory diseases when using different types of inhalers. The secondary outcome is to determine their economic costs and the tertiary outcome is to evaluate the overall environmental footprints of inhalers.We will search for original research articles published until May 30, 2023, using databases such as MEDLINE (OVID), EMBASE (OVID), CENTRAL (OVID), the Canadian Drug and Health Technology Agency, and the US Food & Drug Administration. Our search method follows the PRISMA guidelines 2020. To determine study eligibility, a two-phase screening process will be conducted by three independent reviewers, with predefined outcomes extracted from eligible studies. The study will summarize findings through a narrative synthesis, using statistical analyses and sensitivity tests. In addition, funnel plots and Eggers test will be used for lung deposition analysis, while descriptive statistics will further compare costs and summarize environmental effects. We have ensured that a thorough risk of bias evaluation is part of this research approach, and it is carried out by three independent reviewers using a wide variety of tools according to the type of study.Ethics and DisseminationEthics approval is not required for this study as it constitutes a protocol for a systematic review. The findings from this review will be disseminated via peer-reviewed publications and presented at conferences. Primary data will be available in the online repository on Open Science Framework, alongside a prior registration of this study.OSF Registration Numberosf.io/xc5t6https://doi.org/10.17605/OSF.IO/NT58BStrengths and limitations of this studyThe study will evaluate various aspects of inhaler use, including drug deposition efficiency, environmental sustainability, and cost-effectiveness.The findings aim to inform policy decisions and practice guidelines, focusing on the promotion of sustainable and economically viable healthcare solutions.The study seeks to enhance disease management, improve patient outcomes, and reduce healthcare costs.The study’s findings could be limited by the specific inhaler devices and patient populations examined, which may impact the conclusions’ generalizability.The fast pace of innovation in medical devices could mean that new inhaler technologies may emerge after the study’s completion that are not covered by the review but could have significant implications for patient care.