Inhaler Technique, Critical Errors, and Effective Inspiratory Flow in COPD Patients: A Prospective Study Comparing Patients Over and Under 65 Years of Age

Introduction: Proper inhaler use is critical to the management of chronic obstructive pulmonary disease (COPD), and age plays a significant role in determining the appropriate device. This study evaluated inhaler technique, critical errors, and peak inspiratory flow (PIF) required to activate the inhaler in elderly patients with COPD. Methods: A total of 81 patients with COPD, 41 aged ≤65 years and 40 aged >65 years, using at least one pressurized metered-dose inhaler (pMDI), dry powder inhaler (DPI), or soft mist inhaler (SMI) were included in the study. Inhaler technique was assessed using a checklist and critical errors were identified. PIF was measured with the In-Check DIAL device and compared with the optimal reference value for each type of inhaler. Results: Patients over 65 years of age had lower technique scores (p < 0.001) and a higher incidence of critical errors (p < 0.001) compared with younger patients. Older patients using three inhalers had lower technique scores than those using one or two inhalers (p < 0.001) and had five times more critical errors than younger patients (p < 0.02). A strong correlation between the number of critical errors and technique score was observed in the older group (r = 0.74; p < 0.001). In both groups, critical errors were identified in patients with good or high technical score. With the exception of four older patients, all participants, regardless of age or obstruction severity, achieved the required PIF for proper inhaler activation. Conclusion: In conclusion, patients over 65 years of age with COPD showed a tendency to misuse inhalers, especially pMDIs and multiple inhalers. Patients with adequate or high technique scores in both age groups made critical errors highlighting the importance of investigating the nature of the error regardless of the technique score. By considering the minimum flow value for each inhaler, almost all patients were able to achieve an effective PIF for inhaler activation.