Determinants of Suboptimal Peak Inspiratory Flow Rates among Patients with Chronic Obstructive Pulmonary Disease in Southwest, Nigeria.

Background: Inhalational therapy is the cornerstone in the management of chronic obstructive pulmonary disease (COPD) patients. Patients' peak inspiratory flow impacts effective dry powder inhaler (DPI) delivery and management outcome.
Objective: This study assessed peak inspiratory flow rates (PIFR) and determined the factors associated with suboptimal inspiratory flow rates among COPD patients.
Methods: A descriptive cross-sectional study was conducted among 60 participants (30 stable COPD patients and 30 age-and-sex matched controls). Socio-demographic characteristics was obtained and spirometry was done for all participants. PIFR assessment was done using the In-Check Dial Meter and was categorized as suboptimal (< 60L/min) or optimal (≥ 60L/min). P values less than 0.05 were taken as statistically significant.
Results: Mean age of the COPD patients and healthy controls were both 67.8 ± 10.3 years, with 53.3% being females. Post-bronchodilation FEV 1/FVC% for COPD patients was 54.15 ± 11.27%. The mean PIFR among COPD patients was significantly lower than that of healthy controls, in all DPIs simulated, especially for Clickhaler (46.2±13.4 vs 60.5±11.4L/min, p<0.001). A significant proportion of COPD patients had suboptimal PIFR, in the simulated resistances against Clickhaler and Turbuhaler (70% vs 80%; p<0.001). Older age, shorter height and low BMI were associated with suboptimal PIFR among COPD patients. However, independent predictors of suboptimal PIFR were BMI, PEFR, FEV1% and FVC%.
Conclusion: Suboptimal PIFR was found in a significant number of COPD patients when compared with healthy respondents. Routine assessment using In-Check Dial meter should be done to determine the suitability of dry powder inhalers for patients with COPD.
Competing Interests: The Authors declare that no competing interest exists
(Copyright © 2023 by West African Journal of Medicine.)