Scope of Outcomes in Trials and Observational Studies of Interventions Targeting Medication Adherence in Rheumatic Conditions: A Systematic Review

Abstract

Objective Non-adherence to medications is common in rheumatic conditions and associated with increased morbidity. Heterogeneous outcome reporting by researchers compromises the synthesis of evidence of interventions targeting adherence. We aimed to assess the scope of outcomes in interventional studies of medication adherence. Methods We searched electronic databases to February 2019 for published randomized controlled trials and observational studies of interventions with the primary outcome of medication adherence including adults with any rheumatic condition, written in English. We extracted and analyzed all outcome domains and adherence measures with pre-specified extraction and analysis protocols. Results Overall, 53 studies reported 71 outcome domains classified into adherence (1 domain), health outcomes (38 domains) and adherence-related factors (e.g. medication knowledge) (32 domains). We subdivided adherence into three phases: initiation (n=13 studies, 25%); implementation (n=32, 60%); persistence (n=27, 51%); phase unclear (n=20, 38%). Thirty-seven different instruments reported adherence in 115 unique ways (this includes different adherence definitions and calculations, metric and method of aggregation). Forty-one studies (77%) reported health outcomes. The most frequently reported were: medication adverse events (n=24, 45%); disease activity (n=11, 21%); bone turnover markers/physical function/quality of life (each n=10, 19%). Thirty-three studies (62%) reported adherence-related factors. The most frequently reported were: medication beliefs (n=8, 15%); illness perception/medication satisfaction/satisfaction with medication information (each n=5, 9%); condition knowledge/medication knowledge/trust in doctor (each n=3, 6%). Conclusion The outcome domains and adherence measures in interventional studies targeting adherence are heterogeneous. Consensus on relevant outcomes will improve the comparison of different strategies to support medication adherence in rheumatology.

Long-term outcomes in systemic lupus erythematosus: trends over time and major contributors

“…Poor adherence to therapeutic regimens is a common problem in chronic diseases such as SLE, in which non-adherence rates are as high as 76% in some studies, depending upon the assessment method [ 81 ]. Importantly, adherence measures used in interventional studies are very heterogeneous and consensus on the most relevant outcomes is currently lacking [ 82 ].…”

Patient Perspectives on Outcome Domains of Medication Adherence Trials in Inflammatory Arthritis: An International OMERACT Focus Group Study

“…28,30 While emotional, physical, and social outcomes emerged as relevant outcome domains from the patient perspective, most medication adherence studies report numerical health outcome domains such as joint counts, inflammatory markers, and bone turnover markers. 8 Patients also discussed the importance of addressing outcome domains related to self-management capabilities and the patient-HCP relationship. These outcome domains have not been comprehensively evaluated in trials.…”

“…These outcome domains have not been comprehensively evaluated in trials. 8 Not measuring what patients consider important could lead to medication adherence interventions that comprise little support and potentially limited effectiveness from the patient perspective.…”

“…7 Further, outcome domains and adherence measures included in studies on medication adherence are heterogeneous. 8,9,10,11 There is an urgent need for consensus on a minimum core domain set that matters to patients that should be measured in each adherence trial to reduce inconsistent and selective reporting and improve comparison of interventions. 12 The Outcome Measures in Rheumatology (OMERACT) Adherence Working Group 13 is currently developing a core domain set for trials of medication adherence interventions in patients with rheumatic diseases.…”

Adherence patterns to medications and their association with subsequent hospitalization in adult Egyptian patients with systemic lupus erythematosus

“…17,18 Poor adherence to therapy regimens is a major concern in patients with SLE, in which the non-adherence rate has been shown to be as high as 76% in some studies, depending on the assessment method used. 19 Non-adherence is typically multifactorial and varies according to unintentional and intentional patterns for the majority of patients. 20 A low socioeconomic status, being single, medication side effects, ongoing flares, patient perceptions, knowledge and beliefs about the treatments, including beliefs about medication side effects and effectiveness, co-existing co-morbidities, limited comprehension of physician explanations and instructions, and medication intake more than once a day are all predictors of non-adherence in patients with systemic lupus erythematosus (SLE).…”