Impact of a transition to more restrictive drug formulary on therapy discontinuation and medication adherence.

WHAT IS KNOWN AND OBJECTIVE: There is conclusive evidence demonstrating that formulary restrictions are associated with reduced utilization and pharmacy spending of the restricted drugs. However, prior efforts to implement restrictive formularies have been associated with inconsistent rates of therapy discontinuation and mixed impacts on adherence to therapy. Also, the impact of transferring patients from an already restrictive formulary to a more aggressive model has not been previously examined. This study evaluated the impact of implementation of a more restrictive formulary on therapy disruption, adherence rates, pharmacy costs and generic utilization among patients with common chronic conditions. METHODS: In 2014, CVS Health implemented Value Formulary (VF), a restrictive benefit design with the aim of reducing spending while preserving access to and adherence to essential therapy, was used. A retrospective cohort study was conducted to assess changes in therapy disruption rates, pharmacy costs and generic dispensing rate (GDR) (for continuers) and medication adherence (for initiators) following the implementation of VF. The study group was selected from members of three existing employer clients transitioned from standard formulary (SF) to VF on January 2014. The control population was a matched group of six employers with the same preperiod formulary structure, business unit, adherence programmes and patient out-of-pocket cost as the study group. The control group retained SF in 2014. To assess therapy disruption after VF implementation, we categorized patients by their subsequent medication use into three groups: (i) therapy stopped, (ii) therapy continued and (iii) therapy switched. Medication adherence was measured as monthly proportion of days covered (PDC). Pharmacy cost and GDR were measured per utilizer per month (PUPM). Rates of therapy disruption in study and control groups were compared using the chi-square test. Differences in monthly PDC between matched groups were evaluated using multivariate linear regression. Impact of VF on pharmacy cost and GDR was measured through segmented regression of interrupted time series data with generalized estimating equations. RESULTS AND DISCUSSION: A transition from SF to VF influenced drug coverage for approximately 13% of members (as their medications were either no longer covered, or covered restrictively under VF). Compared to patients whose plan sponsors retained SF, the patients that transitioned to VF had a modest (1·3%) but statistically significant increase in therapy discontinuation rates. This was offset by similarly modest improvements in adherence; patients who initiated therapy under VF demonstrated a 1·5% higher adherence to medications as compared to SF patients (P < 0·001). Medication costs in the VF group were lower by $20 PUPM (P < 0·001), and GDR was greater by 4·2% (P < 0·001). WHAT IS NEW AND CONCLUSION: Transition of patients to a more restrictive drug formulary led to modest therapy discontinuation, similarly modest improvements in medication adherence and substantial prescription drug cost savings. As healthcare payors search for ways to control the rapid rise in spending for medications without compromising quality, the Value Formulary can serve as a useful tool.

Angiotensin receptor blockers and angiotensin-converting enzyme inhibitors: challenges in comparative effectiveness using Medicare data.

An evidence gap exists in comparing the effectiveness of angiotensin receptor II blockers (ARBs) for hypertension with that of angiotensin-converting enzyme inhibitors (ACEIs). We identified elderly hypertensive patients in whom ACEI/ARB therapy had been initiated after hospitalization for coronary artery disease (CAD), heart failure (HF), or stroke and who were eligible for Medicare and state pharmacy assistance programs. Of 18,801 initiators of ACEIs and 2,641 initiators of ARBs, 2,535 died during the follow-up. We observed substantial differences in characteristics between ARB and ACEI initiators, suggesting that ARB users were more health seeking. The incidence of death and sudden cardiac death (SCD) in ACEI initiators was 77 and 22 per 1,000 person-years, respectively. The relative risk for SCD comparing ARB initiators to ACEI initiators was 0.69 (95% confidence interval (CI) 0.50-0.96); when the analysis was restricted to patients with low ejection fraction (EF), the relative risk was 1.1. The reduced risk of SCD can be explained, at least partly, by (i) residual confounding because ARB users were healthier on unobserved domains and (ii) lack of data on EF.

Temporal trends in adherence to cardiovascular medications in elderly patients after hospitalization for heart failure.

Although the complexity of treatment regimens for patients with heart failure (HF) has increased over time because of the increased availability of efficacious medications, little is known about temporal trends in adherence to treatment regimens in these patients. We assessed trends in adherence to angiotensin-system blockers (ABs), ß-blockers (BBs), and spironolactone (SL) for HF in Medicare beneficiaries enrolled in two statewide pharmacy benefit programs from 1995 to 2004. The proportion of days covered (PDC) (%) was assessed after the first dispensing among users of an AB, BB, or SL. Proportions of full adherence (PDC >80%) did not change over time for ABs (54% in both 1996 and 2003) but increased slightly for BBs (from 47% in 1996 to 57% in 2003) and SL (from 31% in 1996 to 42% in 2003). Black race and dialysis treatment predicted poor adherence to any medications. Adherence to BBs and SL increased modestly over time, but overall nonadherence remained high.

Refilling and switching of antiepileptic drugs and seizure-related events.

We sought to estimate the risk of seizure-related events associated with refilling prescriptions for antiepileptic drugs (AEDs) and to estimate the effect of switching between brand-name and generic drugs or between two generic versions of the same drug. We conducted a case-crossover study using health-care databases from British Columbia, Canada, among AED users who had an emergency room visit or hospitalization for seizure (index seizure-related event), defined using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9) codes 345.xx (epilepsy and recurrent seizures) and 780.3x (convulsions), between 1997 and 2005. AED prescription refilling itself was associated with 2.3-fold elevated odds of seizure-related events when the refill occurred within 21 days before the index event (odds ratio (OR) 2.31; 95% confidence interval (CI) 1.56-3.44). The OR was 2.75 (95% CI 0.88-8.64) for refills that involved switching, yielding a refill-adjusted OR for switching of 1.19 (95% CI 0.35-3.99). Refilling the same AED prescription was associated with an elevated risk of seizure-related events whether or not the refill involved switching from a brand-name to a generic product.

A blinded randomized controlled trial of motivational interviewing to improve adherence with osteoporosis medications: design of the OPTIMA trial.

UNLABELLED: We have designed an innovative randomized controlled trial for improving adherence with osteoporosis medications. Recruitment and randomization have been successful. Also, the counseling intervention has been well accepted by subjects randomized to this treatment arm. INTRODUCTION: While many effective treatments exist for osteoporosis, most people do not adhere to such treatments long term. No proven interventions exist to improve osteoporosis medication adherence. We report here on the design and initial enrollment in an innovative randomized controlled trial aimed at improving adherence to osteoporosis treatments. METHODS: The trial represents a collaboration between academic researchers and a state-run pharmacy benefits program for low-income older adults. Beneficiaries beginning treatment with a medication for osteoporosis are targeted for recruitment. We randomize consenting individuals to receive 12 months of mailed education (control arm) or an intervention consisting of one-on-one telephone-based counseling and the mailed education. Motivational interviewing forms the basis for the counseling program which is delivered by seven trained and supervised health counselors over ten telephone calls. The counseling sessions include scripted dialog and open-ended questions about medication adherence and its barriers, as well as structured questions. The primary end point of the trial is medication adherence measured over the 12-month intervention period. Secondary end points include fractures, nursing home admissions, health care resource utilization, and mortality. RESULTS: During the first 7 months of recruitment, we have screened 3,638 potentially eligible subjects. After an initial mailing, 1,115 (30.6%) opted out of telephone recruitment and 1,019 (28.0%) could not be successfully contacted. Of the remaining, 879 (24.2%) consented to participate and were randomized. Women comprise over 90% of all groups; mean ages range from 77 to 80 years old, and the majority in all groups was white. The distribution of osteoporosis medications was comparable across groups and the median number of different prescription drugs used in the prior year was eight to ten. CONCLUSIONS: We have developed a novel intervention for improving osteoporosis medication adherence. The intervention is currently being tested in a large-scale randomized controlled trial. If successful, the intervention may represent a useful model for improving adherence to other chronic treatments.

Interventions to improve adherence and persistence with osteoporosis medications: a systematic literature review.

SUMMARY: Adherence and persistence with osteoporosis medications are poor. We conducted a systematic literature review of interventions to improve adherence and persistence with osteoporosis medications. Seven studies met eligibility requirements and were included in the review. Few interventions were efficacious, and no clear trends regarding successful intervention techniques were identified. However, periodic follow-up interaction between patients and health professionals appeared to be beneficial. INTRODUCTION: Adherence and persistence with pharmacologic therapy for osteoporosis are suboptimal. Our goal was to examine the design and efficacy of published interventions to improve adherence and persistence. METHODS: We searched medical literature databases for English-language papers published between January 1990 and July 2008. We selected papers that described interventions and provided results for control and intervention subjects. We assessed the design and methods of each study, including randomization, blinding, and reporting of drop-outs. We summarized the results and calculated effect sizes for each trial. RESULTS: Seven studies met eligibility requirements and were included in the review. Five of the seven studies provided adherence data. Of those five studies, three showed a statistically significant (p < or = 0.05) improvement in adherence by the intervention group, with effect sizes from 0.17 to 0.58. Five of the seven studies provided persistence data. Of those five, one reported statistically significant improvement in persistence by the intervention group, with an effect size of 0.36. CONCLUSIONS: Few interventions were efficacious, and no clear trends regarding successful intervention techniques were identified in this small sample of studies. However, periodic follow-up interaction between patients and health professionals appeared to be beneficial.