Inhalation Technique Evolution After Training in Copd. The Role of the Device

to test the efficacy of two educational interventions to improve the inhalation techniques per device in patients with COPD and the influence of patient´ preference. Design: Multicenter patients´ preference trial or comprehensive cohort design ISRCTN15106246. Patients: 465 COPD patients (to detect a difference between groups of 25%, 80% statistical power, 95% confidence level, 40% expected losses), with inhaled treatment, written consent. Non-probabilistic consecutive sampling. Allocation: Patients without strong preferences for a treatment are randomised: RCT group (block randomization), and those with strong preferences are given their choice: PPS group. Variables: Primary outcomes: Performance of correct inhalation technique. Independent variables: sex, age, Baseline dyspnea index (BDI), Functional status (forced spirometry). Interventions: Interv-A: Written information. A leaflet with correct inhalation technique. Interv-B: Interv-A + individual training (by instructors). Follow-up: 3 month, visits: baseline (V0), 1 month (V1), 3 month (V2). Statiscal analysis: Mean, frequency, 95% confidence interval. Intention to treat analysis. Males (91.4%), mean age 69.8 years (CI95%, 69.00-70.59); FEV1 (mean) =55.91% (IC95%, 53.62-58.2), mixed respiratory pattern (65.9%). Severity stage: 15.7% mild, 44.1% Moderate, 40.3% Severe. BDI: grade 2. Devices use: 67.3% Handihaler (Hd), 54.8% Turbuhaler (Th), 31.8% Accuhaler (Acc), 26.9% pMDI. Correct Inhalation technique: Hd: RCT-control: 11.7% V0,10% (V2); RCT-intervA: 10.9%, 17.5%; RCT-IntervB: 7.4%, 62.3% p< 0.0001. Th: RCT-control: 22% V0,16.7% (V2); RCT-intervA: 8.7%, 24.4%; RCT-IntervB: 7.5 %, 57.5% p< 0.0001. Acc: RCT-control: 16.1% V0,25% (V2); RCT-intervA: 17.9%, 23.1%; RCT-IntervB: 11.5%, 74.1% p< 0.0001. pMDI: RCT-control: 6.9% V0,3. 6% (V2); RCT-intervA: 12.5%, 19%; RCT-IntervB: 8.3%, 34.6% p=0.025. There were statistically differences for all devices only in the intervention B arms (p<0.0001). The preferences enhanced 1% for Handihaler, 12.7% for Accuhaler, 4.6% for Turbuhaler, 15.4% for pMDI the correct inhalation technique. The performance of a correct inhalation technique improves with monitor training for all devices. The patients´ preferences enhance the efficacy.