A Systematic Review of Published Algorithms for Selecting an Inhaled Delivery System in Chronic Obstructive Pulmonary Disease

Rationale: Medication for treatment of chronic obstructive pulmonary disease (COPD) is available in many different delivery systems; however, national and international guidelines do not provide recommendations on how to select the optimal system for an individual patient. Objectives: To perform a systematic review of published algorithms for inhaler selection in outpatients with COPD. Methods: PubMed, EMBASE, PsycINFO, Cochrane, and Google Scholar were searched for articles on inhaler selection published between January 1, 1990, and March 10, 2021. The results were reviewed for articles containing an algorithm for inhaler selection. The quality of publications containing an algorithm was assessed using the Joanna Briggs Institute's System for the Unified Management, Assessment and Review of Information text and opinion critical appraisal checklist. Individual steps recommended in the algorithms and the order in which they were considered were extracted independently by the two authors using the Joanna Briggs Institute's text and opinion data extraction tool. Textual syntheses and a table of factors included were used to appraise and compare algorithms. Results: The search identified 1,016 publications. After removing duplicate studies (n = 409), 607 abstracts were examined. Nine different algorithms or hierarchical recommendations for device selection were identified. All nine publications were considered of good quality. Most algorithms contain only a few decision steps. There were significant differences between the algorithms. None of the algorithms have been validated. Three domains for factors included in the algorithms were identified: patient factors, device attributes, and healthcare professional (HCP) factors. Patient factors were considered most frequently (19 times) compared with device attributes (10 times) and HCP factors (7 times). Five specific attributes/factors with at least three rankings in different algorithms were identified as key factors for device selection: ability to perform the required inspiratory maneuver and handle device correctly, sufficient inspiratory flow for dry powder inhalers, availability of molecule(s) in the device, and continuity of device. Conclusions: Although the algorithms generally provide step-by-step approaches based on a literature review and/or the experiences of the different authors, none were developed using item generation/reduction methodology or included input from patients with COPD. However, the review identified key factors that should be considered by HCPs when selecting therapy. Registration: PROSPERO (CRD42021244475).