Role of Side Effects, Physician Involvement, and Patient Perception in Non-Adherence with Oral Bisphosphonates

The benefits of osteoporosis therapy are compromised by low adherence, thus requiring a better understanding of its barriers and unmet needs. The objective of this study was to assess reasons for non-adherence with oral bisphosphonates among osteoporotic women.

A cross-sectional patient survey of women who initiated therapy with risedronate or alendronate between the years 2010 and 2012 were non-adherent [Medication Possession Ratio (MPR) <70%] or switched therapy within the first year. Survey participants were identified using Maccabi Health Services computerized database. Patients who gave informed consent completed a 20-min telephonic survey, assessing reasons for discontinuation or switching, including physician involvement, side effects, administration regimen, perceptions of bone health, and medications' efficacy.

The study population included 493 females (mean age = 66 ± 7) of whom 40% discontinued all anti-osteoporotic therapy (mean MPR = 19%), 9% remained on initial therapy (mean MPR = 47%), and 51% switched therapy (mean MPR = 62%). Family history, fracture history, socioeconomic status, and index drug class and frequency were similar in all groups. The most common reasons for switching or discontinuation of the first-line therapy were gastrointestinal side effects, such as heartburn, acid reflux or other (40.0%), and physician recommendation (26.7%). The major reasons for complete discontinuation of therapy were side effects (26.9%) and physician recommendation (20.0%). Perceived low importance was more commonly mentioned than high cost of medication (14% vs. 3%).

Our findings highlight the importance of low tolerability to non-adherence with osteoporosis therapy and underlines poor patients' awareness and sub-optimal physicians' involvement in conveying the importance of this therapy.

Merck & Co Inc.