Impact of pharmacist-led intervention in medication adherence and inhaler usage on asthma and chronic obstructive pulmonary disease control: a quasi-experimental study

Abstract

Background Despite recent advances in the management of asthma and chronic obstructive pulmonary disease (COPD), patients still experience suboptimal disease control largely due to medication non-adherence and inappropriate use of inhaler. This study evaluates the impact of pharmacist-led intervention in medication adherence and inhaler usage on asthma and COPD control among out-patients attending the premier tertiary hospital in Nigeria. Method A quasi-experimental study carried-out among eligible out-patients attending pulmonology clinic of University College Hospital, Ibadan. Baseline questionnaire explored medication adherence using a comprehensive-medication-adherence-assessment-scale (CMAAS-12) developed by the study co-investigators, use of pressurized-metered-dose (pMDI) and Diskus inhalers, as well as asthma/COPD control using validated asthma control test (ACT) and COPD assessment test (CAT). Subsequently, patients were allocated into control ( n = 65) or intervention group ( n = 65) using odd or even number. Intervention group received 2-month follow-up educational and/or cognitive-behavioural interventions to resolve identified adherence barriers, while control group continued with traditional care. Descriptive statistics, Chi-square and Wilcoxon-signed-ranked tests were used for analysis at p < 0.05. Results Overall, patients with optimal adherence were 11(18.6%) and 16(27.1%), p = 0.132 (control), but 20(33.3%) and 38(63.3%), p < 0.001 (intervention) at baseline and post-baseline, respectively. Specifically, in the intervention group, the identified adherence barriers at baseline were summarized into knowledge (120;40.4%), practical (115;38.7%) and attitudinal (62;20.9%). Patients with correct use of pMDI were 11(21.6%) baseline and 19(36.5%) post-baseline, p = 0.011 (control), but 13(22.8%) and 46(80.7%) respectively, p < 0.001 (intervention). Correct use of Diskus inhaler were 5(50.0%) and 4(40.0%), p = 0.157 (control), but 7(35.0%) and 14(70.0%), p = 0.025 (intervention) at baseline and post-baseline, respectively. Patients with ‘well-controlled asthma’ were 25(44.6%) and 26 (47.3%), p = 0.025 (control), but 18(35.3%) and 32(60.4%), p < 0.001 (intervention) at baseline and post-baseline, respectively. The COPD-specific health status indicated that 0(0.0%) and 1(14.3%), p = 0.059 (control), but 0(0.0%) and 7(50.0%), p < 0.001 (intervention) at baseline and post-baseline, respectively, belonged to ‘low COPD impact’. Conclusion Pharmacist-led intervention significantly enhanced medication adherence and appropriate use of inhaler among the intervention ...