Internal medicine

Dry-powder inhaler

Inhaler

Population

Asthma

Spirometer

COPD

Peak flow meter

Spirometry

Exhaled nitric oxide

Medicine

Environmental health

International Journal of 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. Keywords: pulmonary disease, chronic obstructive, dry powder inhaler, peak inspiratory flow rate, drug delivery systems

&lt;p&gt;Prevalence and factors associated with suboptimal peak inspiratory flow rates in COPD&lt;/p&gt;

&lt;p&gt;Prevalence and factors associated with suboptimal peak inspiratory flow rates in COPD&lt;/p&gt;

<p>Prevalence and factors associated with suboptimal peak inspiratory flow rates in COPD</p>