Capsule commentary on Zhang et al., Race/ethnicity, Disability, and Medication Adherence Among Medicare Beneficiaries with Heart Failure

Background: When using inpatient claims data to identify hospitalizations in supplemental Medicare beneficiaries, e.g., in the MarketScan database, there is a concern that the coverage of hospitalizations in such inpatient claims may be incomplete. However, whether hospitalizations are covered by inpatient claims or not, they incur professional charges that are recorded in the professional claims data in the MarketScan Medicare database. In the context of identifying hospitalizations that might be related to heart failure (HF) in dronedarone users, we compared different approaches to identify such hospitalizations. Objective: To assess the impact of using professional claims in addition to inpatient claims on identifying hospitalizations that might be related to HF. Methods: A total of 20,834 dronedarone users who were supplemental Medicare beneficiaries between July 2009 (launch date in US) and December 2012 were identified in the MarketScan database. The hospitalizations that might be related to HF within 30 days prior to initiating dronedarone were identified by searching (1) inpatient claims and (2) both inpatient and professional claims using related ICD-9-CM diagnosis codes for HF and Current Procedural Terminology codes for hospitalizations. Results: A total of 1,162 patients who had HF hospitalizations within 30 days prior to initiating dronedarone were identified by searching inpatient claims between July 2009 and December 2012. Supplementing with professional claims identified an additional 177 patients who had HF hospitalizations, increasing the total number to 1,339. Therefore, 13.2% (177/1,399) of the patients who had HF hospitalizations could only be identified in professional claims. Thus, the prevalence of hospitalizations that might be related to HF within 30 days prior to initiating dronedarone was 5.6% (1,162/20,834; 95% confidence interval (CI): 5.3 - 5.9%) when hospitalizations were identified using inpatient claims alone. Adding professional claims in the search algorithm, the prevalence of HF hospitalizations was 6.4% (1,339/20,834, 95% CI: 6.1 - 6.8%). Conclusions: Using professional claims, in addition to inpatient claims, can improve the identification of hospitalizations that might be related to HF.

Download Full-text

Abstract 148: Association of Dosing Frequency on Medication Adherence in Patients with Non-Valvular Atrial Fibrillation

Circulation Cardiovascular Quality and Outcomes ◽

10.1161/circoutcomes.6.suppl_1.a148 ◽

2013 ◽

Vol 6 (suppl_1) ◽

Author(s):

Tanya Burton ◽

Lauren J Lee ◽

Ying Fan ◽

Winghan Jacqueline Kwong

Keyword(s):

Heart Failure ◽

Atrial Fibrillation ◽

Medication Adherence ◽

Health Plan ◽

Index Date ◽

Improve Medication Adherence ◽

Treatment Regimens ◽

Pharmacy Claims ◽

Comorbidity Burden ◽

Dosing Frequency

Objective: Previous studies suggest that the complexity of a dosing regimen may affect medication adherence. We examined the association between dosing frequency and adherence for 2 concomitant medications commonly prescribed to patients with non-valvular atrial fibrillation (NVAF), metoprolol (MET) and carvedilol (CAR). Methods: A retrospective claims study from a large US commercial and Medicare Advantage health plan analyzed data of adults ( > 18 years) with 1 inpatient or 2 outpatient claims for NVAF between 1/1/2008 - 12/31/2010. Patients with > 2 pharmacy claims for MET or CAR were analyzed separately. Within MET and CAR samples, once-daily (QD) and twice-daily (BID) cohorts were defined by the dosing frequency on pharmacy claims. The index date was set as the date of the first MET or CAR claim. Patients were continuously enrolled in the health plan for 1 year before (pre-index) and 1 year after (post-index) the index date. MET patients were required to have > 1 pre-index claim for acute myocardial infarction, angina, heart failure, or hypertension; CAR patients were required to have ≥1 claim for heart failure or hypertension. Patients using both QD and BID formulations of the index medication were excluded. Adherence to the index medication was assessed by the proportion of days covered (PDC) during the post-index period. PDC between QD and BID patients was compared using logistic regression to adjust for demographic and pre-index clinical characteristics. The proportion of QD and BID patients who discontinued the index medication (defined by a gap > 30 days) during the post-index period was also compared. Results: The analysis included 11,621 MET patients (QD: 6,084; BID: 5,537) and 4,393 CAR patients (QD: 203; BID: 4,190). Mean (SD) age was 70 (12) years for MET and CAR patients; 59% of MET and 69% of CAR patients were male. Compared to patients with BID dosing, patients with QD dosing were on average younger, more likely to be male, and had a lower comorbidity burden. Fewer patients discontinued MET or CAR with QD than BID dosing (MET: 38% vs. 51%, p<0.001; CAR: 39% vs. 48%, p=0.009). The proportion of patients with PDC > 80% was greater for patients with QD than BID dosing (MET: 62% vs. 50%, p< 0.001; CAR: 63% vs. 53%, p=0.004). MET patients with BID dosing were less likely to achieve PDC > 80% than patients with QD dosing (adjusted OR: 0.66; 95% CI: 0.609-0.712). CAR patients with BID dosing were less likely to achieve PDC > 80% than patients with QD dosing (adjusted OR: 0.69; 95% CI: 0.508-0.934). Among MET and CAR patients, age <60 years was associated with lower adherence (p<0.001) while prior use of index medication was associated with higher adherence (p≤0.001) to the index medication. Conclusion: Medication adherence to MET and CAR was higher with QD than BID dosing. Quality initiatives that reduce the dosing frequency of treatment regimens may improve medication adherence among NVAF patients.

Download Full-text