The impact of medication synchronization programs on medication adherence: A meta-analysis

Abstract

Background: Medication nonadherence is associated with more than $100 billion in preventable medical costs each year in the United States. Medication synchronization (med sync) programs have emerged as a potential solution to addressing nonadherence.

Objectives: To assess the impact of med sync programs on adherence in adults on chronic medications through a meta-analysis.

Methods: A comprehensive literature search was conducted for studies of med sync and adherence in adults published in English from database inception to May 2020. Studies were included if they provided a description of the med sync program, reported a quantitative measure of medication adherence using the proportion of days covered metric, and were conducted in the United States. The search terms included "medication synchronization," "med sync," "adherence," and "PDC." Pooled odds ratios (ORs) and 95% CIs using random-effects models were calculated to assess overall impact and subgroup analyses. The risk of bias of individual studies was assessed using the Downs and Black checklist.

Results: Nine studies reporting 30 effect sizes were included in the meta-analysis. On the basis of the Downs and Black checklist, the methodological quality of the studies was fair (mean [SD] 17.6 [1.7]). Med sync was associated with greater odds of adherence (pooled OR 2.29 [95% CI 1.99-2.64], I² = 93.3%, τ² = 1.11). In addition, the type of med sync program influenced the variation in effect sizes (Cochran Q statistic [Q_between] = 45.4, P < 0.001), with appointment-based med sync programs having the largest impact on adherence (3.14 [95% CI 2.72-3.63]).

Conclusion: In this meta-analysis of the impact of med sync on adherence, med sync was associated with statistically significant improvement in adherence. Policy makers and payers should consider reimbursement to pharmacies to support med sync programs in efforts to combat medication nonadherence and improve health outcomes.