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Development of a Scoring System to Predict Suboptimal Peak Inspiratory Flow in Patients With Chronic Obstructive
Sang Hyuk Kim1,2, Youlim Kim3, Chin Kook Rhee4
1Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Internal Medicine, Dongguk University Gyeongju Hospital, Dongguk University College of Medicine, Gyeongju, Korea.
Background:
Peak inspiratory flow rate (PIFR) is a critical indicator for the successful use of dry powder inhalers (DPIs). However, resource constraints often limit the practicality of measuring PIFR prior to DPI prescription.
Methods:
A cross-sectional observational study was conducted across seven hospitals in Korea, including patients with chronic obstructive pulmonary disease (COPD). To develop a scoring system to predict suboptimal PIFR without direct measurement, variables were selected through a literature review and logistic regression model, considering practicality in clinical settings.
Results:
The study involved 436 patients and was divided into training and test datasets with a 7:3 ratio. Age (≥ 80 years), weight (≤ 60 kg), modified Medical Research Council score (≥ 2), and post-bronchodilator forced vital capacity (≤ 80%pred) were selected to develop the scoring system. The developed scoring system, ranging from 0 to 4 points with a 2-points threshold for predicting suboptimal PIFR, demonstrated acceptable predictive ability for suboptimal PIFR in training (area under the receiver operating characteristic [AUROC], 0.724; 95% confidence interval [CI], 0.660-0.789) and test datasets (AUROC, 0.686; 95% CI, 0.591-0.781).
Conclusion:
Our developed scoring system demonstrated an acceptable predictive ability for suboptimal PIFR in COPD patients, utilizing variables that are easily applicable in clinical practice.
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