Table 1

General characteristics of the eight included studies

AuthorYearCountryStudy designSample sizeAgeAdherence assessment methodThresholdProportion of adherent patients
Chen et al362020ChinaRetrospective
Observational cohort
11 708No age minimum, no mean/median/range presentedPDC≥0.80 (sensitivity analysis for cut-off at 0.50)10.8% in total;
36.3% in LABA and/or LAMA group,
26.4% in LABA/ICS group and 1.8% in oral mucolytic therapy group
Davis et al332017USARetrospective
Observational cohort
13 657≥40 years, mean age of 67 yearsPDCAdherent: PDC≥0.80,
mildly non-adherent: 0.50≤PDC<0.80, moderately non-adherent:
0.30≤PDC<0.50 and
highly non-adherent: PDC<0.30
13.9% in LABA/ICS group
Fan et al302003USAProspective
Observational cohort
8033≥45 years% of days supplied during fixed time period of 90 days>0.8033% in ICS group
Humenberger et al312018AustriaRetrospective
Observational cohort
357>40 years, mean age of 66.5 years (SD 10.6)MPRComplete adherence: >0.80, partial adherence: 0.50–0.80 and low adherence: <0.5033.6% in total (LAMA, LABA, LABA/ICS, LABA/LAMA and LABA/LAMA/ICS users together)
Ismaila et al82014CanadaRetrospective
Observational cohort
23 707≥40 years, mean age of 73.2 years (SD 10.3)MPR≥0.8061.1% in LAMA monotherapy group, 62.9% to LAMA in LABA/LAMA/ICS group and 35.4% to LABA/ICS in LABA/LAMA/ICS group
Mueller et al352017GermanyRetrospective
Observational cohort
45 937≥40 years, mean age of 71.4 years (SD 11.4)MPR≥0.8030.0% in total; 38.0% in LABA group, 53.2% in LAMA group, 20.4% in ICS group and 26.8% in LABA/ICS group
Punekar
et al32
2015UKRetrospective
Observational cohort
17 529≥40 yearsMPR≥0.8034% in LABA group; 42% in LAMA group and 34% in LABA/ICS group
Wurst et al342014USARetrospective
Observational cohort
3268≥40 to 65 years, mean age of 55.8 years (SD 5.4)MPR and PDC≥0.8029.4% in LABA group and 37.1% in LAMA group
  • ICS, inhaled corticosteroids; LABA, long-acting beta agonist; LAMA, long-acting muscarinic antagonist; MPR, medication possession ratio; PDC, proportion of days covered.