<p>Association Between Adherence to Maintenance Medication in Patients with COPD and Acute Exacerbation Occurrence and Cost in China: A Retrospective Cohort Database Study</p>

Abstract

Background: This study aimed to evaluate the association between adherence to maintenance medication (ie, inhaled bronchodilators, inhaled corticosteroid/long-acting beta-2 agonist [ICS/LABA] combinations, and oral therapy) and acute exacerbation of chronic obstructive pulmonary disease (AECOPD) and related costs among patients with chronic obstructive pulmonary disease (COPD) in China. Patients and Methods: Claims data from the hospitals of a metropolitan city in south China between January 2014 and December 2016 were obtained. Patients with COPD with ≥2 maintenance medication claims during 1 year were included. Adherence was measured by the proportion of days covered (PDC). The interaction of medication class×adherence was considered when building models. Results: A total of 11,708 patients met the inclusion criteria, of whom 10.8% were highly adherent (PDC≥0.8). There were significant interaction effects of drug category on hospitalized AECOPD risk (P≤0.001), hospitalized AECOPD rate (P<0.001), and 1-year hospitalized AECOPD treatment costs (P=0.012). There was a relationship between high adherence and outcomes for ICS/LABA combinations (n=3,419), ie, relative risk of hospitalized AECOPD was reduced by 34.8% (adjusted odds ratio=0.65; 95% confidence interval (CI): 0.54-0.79; P<0.001) while the frequency of hospitalized AECOPD per patient-year was reduced by 24.4% (adjusted rate ratio=0.76; 95% CI: 0.65 to 0.87; P<0.001). Mean 1-year per-patient hospitalized AECOPD costs were reduced by 37.8% (mean difference=−848 USD; 95% CI: −1435-262 USD; P<0.001). Patients taking oral mucolytics and having high adherence had worse AECOPD outcomes than patients with poor adherence. Conclusion: High adherence to ICS/LABA maintenance therapy was associated with reduced hospitalized AECOPD rates and costs in Chinese patients with COPD.

Global burden of medication non-adherence in chronic obstructive pulmonary disease (COPD) and asthma: a narrative review of the clinical and economic case for smart inhalers

“…In patients with over 80% adherence, clinical outcomes improve significantly. Indeed, higher adherence was associated with less hospitalizations, exacerbations and emergency department visits, and with better lung function (17,50). Furthermore, in a post-hoc analysis, good adherence was associated with a lower mortality rate among patients with COPD, although "the healthy adherer effect" (i.e., the phenomenon that good adherence is an indicator for an overall healthier lifestyle) may partly explain this (51).…”

“…Globally, asthma and COPD adherence rates are generally very poor. For example, patients with COPD have an adherence rate of only 22% in South-Korea, 29.2% in China, 34.8% in Italy, 23.9% in Belgium, 32.4% in Spain, 25% in Canada, 23.4% in the United States (US) and 27.4% in Nigeria (Figure 1) (9,(15)(16)(17)(18)(19)(20)(21). Except for Brazil and Italy, with an adherence rate of 52% and 43.8% among patients with asthma, respectively, the adherence rate of patients with asthma is not much better: patients with asthma in US are for 22.2% adherent, in France for 24.9%, in Ethiopia for 18%, in Saudi-Arabia for 27.4%, in China for 13.8%, in Australia for 19.4% and in New-Zealand for only 30% (Figure 1) (22)(23)(24)(25)(26)(27)(28)(29)(30).…”

“…The economic consequences are expressed in direct and indirect costs, direct costs are healthcare costs (e.g., hospitalizations, medication) and indirect costs are societal costs (e.g., loss of productivity, missed workdays) (57). Non-adherence in patients with asthma/COPD is associated with high healthcare and societal costs due to exacerbations, hospitalizations, missed school and workdays and loss of productivity (7,16,17,48).…”

Adherence to inhaler treatments in obstructive lung diseases: A different perspective

“…Strict patient adherence to inhaler therapies in asthma and chronic obstructive lung disease (COPD), together with correct application of the inhaler technique, are the two most critical issues in obtaining the desired treatment results [1,2]. However, studies clearly show that adherence with inhaler treatments is insufficient in patients with asthma and COPD [3,4].…”

“…In a study conducted with difficult asthmatics, it was found that low adherence was more common in women and was associated with repeated hospitalizations as well as frequent use of nebulized bronchodilator medication [3]. A retrospective cohort study examining 11,708 COPD patients in China showed that using ICS / LABA combination maintenance therapy with high adherence levels resulted in 34.8% less hospitalizations due to exacerbations compared to those using this treatment low adherence [4].…”