Evaluating the Effectiveness of Written Dry Powder Inhaler Instructions and Health Literacy in Subjects Diagnosed With COPD

BACKGROUND: Improper inhaler use results in decreased drug deposition in the lungs. The impact of health literacy and poor vision on the patient's ability to learn inhaler technique by reading instructions has not been confirmed. This study evaluated the effectiveness of learning inhaler technique from written instructions and the impact of health literacy for patients diagnosed with COPD who used a dry powder inhaler (DPI). METHODS: This pilot study recruited subjects diagnosed with COPD. A trained assessor scored subjects' inhaler technique before and after reading the appropriate American College of Chest Physicians handouts. Peak inspiratory flows (PIFs) were measured using an InCheck Dial. Health literacy was measured by the S-TOFHLA (Short Test of Functional Health Literacy in Adults), and visual acuity was measured by a Snellen chart. Associations between health literacy and visual acuity and changes in subjects' inhaler technique scores were assessed by Spearman's rho. Inhaler technique change scores were assessed by the Wilcoxon signed-rank test at P =.05. RESULTS: Of the 24 participants enrolled, 63% were female, mean age was 65.6 y, and 83% were Global Initiative for Chronic Obstructive Lung Disease air-flow limitation 2 or 3. Wilcoxon scores were significant for improved total scores for both the Diskus and HandiHaler, with medians improving from 6.5 to 7.0 (interquartile range 6.0-7.8) (P =.047) and from 6.0 to 7.5 (interquartile range 7.0-9.0) (P =.002), respectively. The minimum required PIF was achieved by 93.8% of the Diskus and 94.4% of the HandiHaler groups. There were no associations detected between the handout intervention (Diskus and HandiHaler) and health literacy level and vision. CONCLUSIONS: The educational handouts for DPIs helped participants already using a DPI to improve their inhaler technique. Stable participants diagnosed with COPD are able to generate appropriate PIFs to properly use DPIs. Neither vision nor health literacy was associated with the inability to learn inhaler technique from patient education inhaler device handouts.