Psychometric properties of the Osteoporosis-specific Morisky Medication Adherence Scale in postmenopausal women with osteoporosis newly treated with bisphosphonates.

BACKGROUND: Poor adherence to oral osteoporosis medications is common. Strategies for improving adherence begin with identification of the problem. The 8-item Morisky Medication Adherence Scale for self-reported adherence to antihypertensive medications was modified for assessing adherence to oral osteoporosis medications. An evaluation of the measurement properties of the Osteoporosis-Specific Morisky Medication Adherence Scale (OS-MMAS) was needed. OBJECTIVE: To examine the psychometric properties of the OS-MMAS in women with postmenopausal osteoporosis. METHODS: Five hundred women aged 55 years and older with osteoporosis who were newly prescribed daily or weekly oral bisphosphonates between May 15, 2010, and August 15, 2010, were randomly selected from Kaiser Permanente Southern California, a large integrated health care delivery system, and mailed a self-administered survey that included the 8-item OS-MMAS, Self-Efficacy for Appropriate Medication Use Scale (SEAMS), Beliefs about Medicines Questionnaire (BMQ), Treatment Satisfaction Questionnaire for Medication (TSQM), Gastrointestinal Symptom Rating Scale (GSRS), and 12-item Short-Form Health Survey (SF-12v2). OS-MMAS scores can range from 0 to 8, with higher scores indicating better medication adherence. Internal consistency reliability was evaluated using Cronbach α coefficient. Test-retest reliability was assessed using intraclass correlation coefficients (ICCs) in a subset of 102 participants. Construct validity was assessed using confirmatory factor analysis and correlations between OS-MMAS and related measures. RESULTS: Of 197 participants, 150 reported that they were still taking their bisphosphonate at the time of the survey and completed the OS-MMAS. Overall, 30.7%, 32.7%, and 36.7% had low, medium, and high OS-MMAS scores (<6, 6 to <8, and 8, respectively). Cronbach α was 0.82 and the ICC was 0.77. Convergent validity was supported by significant correlations with SEAMS, BMQ necessity, and TSQM scores. In confirmatory factor analysis, a single-factor scale was supported. CONCLUSIONS: The OS-MMAS showed strong psychometric properties with good reliability and construct validity and may provide a valuable assessment of self-reported medication adherence in women newly prescribed oral osteoporosis medications.

Role of RANK ligand and denosumab, a targeted RANK ligand inhibitor, in bone health and osteoporosis: a review of preclinical and clinical data.

BACKGROUND: Postmenopausal osteoporosis results from bone loss and decreased bone strength mediated by an increased rate of bone remodeling secondary to reduced estrogen levels. Remodeling cycles are initiated by osteoclasts, the formation, function, and survival of which depend on RANK ligand (RANKL). RANKL inhibition therefore represents a novel strategy for reducing remodeling and its effects on fracture risk. OBJECTIVES: The goal of this study was to review the preclinical and clinical evidence supporting the value of RANKL inhibition in conditions of bone loss and to provide the rationale for the use of the fully human antibody denosumab, a RANKL inhibitor, in such conditions. METHODS: We searched PubMed from January 2005 to May 2011 using the following terms: RANK Ligand, RANKL, denosumab, and NOT cancer, metastatic bone, or rheumatoid in the title. RESULTS: The search method retrieved 111 articles. Preclinical evidence from several bone disease models suggests that RANKL inhibition leads to increased bone volume, density, and strength. Denosumab prevents RANKL from binding to its receptor, decreasing osteoclast activity and thereby reducing bone resorption and increasing cortical and trabecular bone mass and strength. It has consistently been reported to reduce bone turnover, increase bone density, and reduce the risk of fracture in clinical studies of postmenopausal women. Phase III head-to-head trials comparing denosumab with the bisphosphonate alendronate reported that denosumab was associated with significantly greater increases in bone density. Eczema as an adverse event and cellulitis as a serious adverse event were more common with denosumab than with placebo. CONCLUSIONS: Preclinical studies defined the role of RANKL in bone remodeling and provided evidence for the therapeutic potential of RANKL inhibition in conditions of bone loss. Clinical studies evaluating RANKL inhibition with denosumab in postmenopausal women have reported significant reductions in vertebral, nonvertebral, and hip fractures, providing evidence compatible with the use of denosumab in postmenopausal women with osteoporosis.