Effect of pharmacist-led interventions on medication adherence and inhalation technique in adult patients with asthma or COPD: A systematic review and meta-analysis.

OBJECTIVE: In patients with asthma and chronic obstructive pulmonary disease (COPD), disease control is still suboptimal-incorrect inhalation technique and medication non-adherence are two important reasons for this outcome. Pharmacists' interventions have been shown to have a positive effect on the clinical outcomes of asthma and COPD. Quantitative assessment of the efficacy of pharmacist-led interventions, mainly on inhalation techniques and medication adherence, is needed. Evidence for different interventions is not totally conclusive, and no results of theory-based adherence promotion interventions for asthma and COPD have been published. The objective of our study is to evaluate the effect of pharmacist-led interventions on asthma and COPD management, focusing mainly on inhalation technique and medication adherence, and whether the content of interventions (categorized based on Information-Motivation-Behavioural skills (IMB) model) affects the effectiveness and whether the IMB model is worthy of clinical promotion and application in adults with asthma or COPD.
METHODS: The PubMed, EMBASE, The Cochrane Library, Web of Science and ClinicalTrials.gov databases were searched for randomized controlled trials that involved pharmacist-led interventions among patients with asthma or COPD. We used database-specific vocabulary (eg, Medical Subject Headings) and free text terms expanding from 'asthma', 'COPD' and 'pharmacist' to identify relevant articles. Two reviewers independently selected the studies, assessed the risk of bias and extracted the data. The meta-analysis was performed in Review Manager 5.3 provided by the Cochrane Collaboration. PROSPERO registration number: CRD42019144793. RESULTS AND DISCUSSION: Thirteen studies were eligible for qualitative analysis, and 12 studies were included in the meta-analysis. Pharmacist-led interventions showed a positive effect on medication adherence (1.34 [95% CI 1.18-1.53], P < .0001) and inhalation technique (1.85 [95% CI 1.57-2.17], P < .00001) in COPD and asthma patients. In the subgroup meta-analysis, significant medication adherence improvement was found only in COPD patients (1.41 [1.24-1.61], P < .0001). The subgroup meta-analysis also noted that interventions that included all three Information-Motivation-Behavioural skills (IMB) constructs had a significant improvement in medication adherence (1.41 [1.24-1.61], P < .0001). Subgroup meta-analysis conducted between different diseases, different intervention contents, and different measure tools did not significantly change the heterogeneity. WHAT IS NEW AND
CONCLUSION: Pharmacist-led interventions can improve inhalation technique in adult asthma and COPD patients. Significant improvement in medication adherence was found only in COPD patients. The effect among asthmatic patients requires further study. Interventions based on the IMB model may be worthy of clinical promotion and application. More future research is needed to establish solid evidence base for effective interventions and uniform measurement of medication adherence.