Association between adherence to medications for COPD and medications for other chronic conditions in COPD patients

Abstract

BackgroundPatients with COPD often have multiple comorbidities requiring use of multiple medications, and adherence rates for maintenance COPD (mCOPD) medications are already known to be suboptimal. Presence of comorbidities in COPD patients, and use of medications used to treat those comorbidities (non-COPD medications), may have an adverse impact on adherence to mCOPD medications.ObjectiveThe objective of the study was to evaluate the association between non-adherence to mCOPD medications and non-COPD medications in COPD patients.MethodsCOPD patients were identified using a large administrative claims database. Selected patients were 40–89 years old and continuously enrolled for 12 months prior to and 24 months after the first identified COPD diagnosis (index date) during January 1, 2009 to December 31, 2010. Patients were required to have ≥1 prescription for a mCOPD medication within 365 days of the index date and ≥1 prescription for one of 12 non-COPD medication classes within ±30 days of the first COPD prescription. Adherence (proportion of days covered [PDC]) was measured during 365 days following the first COPD prescription. The association between non-adherence (PDC <0.8) to mCOPD and non-adherence to non-COPD medications was determined using logistic regression, controlling for baseline patient characteristics.ResultsA total of 14,117 patients, with a mean age of 69.9 years, met study criteria. Of these, 40.9% were males and 79.2% were non-adherent to mCOPD medications with a mean PDC of 0.47. Non-adherence to mCOPD medications was associated with non-adherence to 10 of 12 non-COPD medication classes (odds ratio 1.38–1.78, all P<0.01).ConclusionAdherence to mCOPD medications is low. Non-adherence (or adherence) to mCOPD medications is positively related to non-adherence (or adherence) to non-COPD medications, implying that the need to take medications prescribed for comorbid conditions does not adversely impact adherence to mCOPD medications.

Nonadherence to treatment and quality of life among patients with chronic obstructive pulmonary disease

“…[ 26 ] Furthermore, multivariate analysis failed to find significant association between nonadherence and comorbidities. This is inconsistent with previous studies[ 24 27 28 ] that have suggested that comorbidities are one of the greatest barriers to achieve medication adherence.…”

<p>Medication adherence and persistence in chronic obstructive pulmonary disease patients receiving triple therapy in a USA commercially insured population</p>

“…Problems with medication adherence among patients with COPD have been well documented worldwide 35–39. Dhamane et al, using a large administrative claims database (N=14,117; mean age, 69.9 years), observed that 79.2% of patients were nonadherent to maintenance COPD medications with a mean PDC of 0.47 40. In another recent large retrospective cohort study based on claims data provided by a German statutory health insurance fund (N=45,937), and Mueller et al, it was reported that approximately two-thirds of patients with COPD failed to continue treatment after 12 months 41.…”

Inhalation therapy in the next decade: Determinants of adherence to treatment in asthma and COPD

“…Low expectation of the medication, presence of comorbid illnesses, depressed mood, increased age, current smoking, and lack of confidence in the provider are the most consistent independent predictors of low adherence [204]. Adherence to medications may be impacted by factors that do not change regardless of disease or medication type but reasonably is influenced by aspects of patient-related considerations (forgetfulness, suboptimal health knowledge, etc.…”