Investigating the Accuracy of the Digihaler, a New Electronic Multidose Dry-Powder Inhaler, in Measuring Inhalation...

The Digihaler^® is a Food and Drug Administration-approved, digital multidose dry powder inhaler with an integrated electronic module that provides patients and health care professionals with feedback on inhalation parameters, including usage, adherence, and technique. This study compared inhalation parameters measured using the Digihaler with readings made simultaneously using an inhalation profile recorder (IPR). This single-visit, open-label study enrolled children (4-17 years) and adults (18-55 years) with asthma, and adults (≥55 years) with chronic obstructive pulmonary disease (COPD). Participants made three separate inhalations using an empty Digihaler device, each measured simultaneously by the Digihaler and IPR. Inhalation profiles were downloaded from the devices at the end of the study. Inhalation parameters measured included peak inspiratory flow (PIF) and inhaled volume (inhV). The profile with the highest PIF and corresponding IPR profile were analyzed. Overall, 150 participants were enrolled; inhalation data were available for 148 (50 children and 49 adults with asthma, and 49 with COPD). Mean (standard deviation [SD]) age was 39.1 (24.5) years; 51% of participants were male. Overall mean (SD) PIFs as measured by the Digihaler and IPR were 70.62 (17.73) L/min and 72.55 (19.42) L/min, respectively, with a mean percentage difference of -1.75% (95% confidence interval [CI]: -3.64 to 0.15). Mean percentage differences between the Digihaler and IPR measurements of PIF ranged from -2.97% among adults with COPD to 0.16% among children with asthma. Overall mean (SD) inhV for the Digihaler and IPR were 1.57 (0.69) L and 1.67 (0.73) L, respectively, with a mean percentage difference of -6.11 (95% CI: -8.08 to -4.13). There was a strong correlation between PIF and inhV measurements taken by the Digihaler and those taken by the IPR (Spearman's correlation coefficient = 0.96). Our findings confirm the ability of the Digihaler to provide accurate measurement of inhalation parameters when used by patients.