Adherence, patient preference and dosing frequency: understanding the relationship.

Adherence to treatment among patients with chronic diseases is currently suboptimal. Poor adherence leads to reduced clinical benefit, a raised incidence of secondary complications and therefore increased healthcare costs. For patients with osteoporosis, long-term adherence to therapy is further complicated by the asymptomatic nature of the disease and the lack of options for patient self-monitoring. Bone densitometry and biochemical markers of bone turnover are assessments that could be used by physicians to provide feedback to patients on the effectiveness of medication. However, these feedback systems are costly and not readily available. Oral bisphosphonates are currently the first-line therapy for postmenopausal osteoporosis. However, they are associated with stringent dosing procedures, and some patients may experience upper gastrointestinal side-effects following administration. Alarmingly, approximately 50% of patients discontinue daily bisphosphonate therapy within 1 year, which negatively impacts upon treatment outcomes, leading to a reduced antifracture effect. Thus, there is a need for an effective therapy that enhances patient adherence. The impact of reducing bisphosphonate dosing frequency on therapeutic adherence has been documented in several studies. Data have shown that, although weekly dosing improves adherence compared with daily administration, levels are still suboptimal. Results from two recent studies that have assessed patient preference for a once-monthly compared with a weekly dosing schedule have demonstrated that patients prefer a monthly regimen (67-71%). Their reasons for preferring once-monthly dosing were that it would fit better with their lifestyle (49-77%) and would be more convenient (75%). A novel once-monthly bisphosphonate regimen, such as the ibandronate regimen, may therefore help patients to follow dosing guidelines and encourage them to stay on therapy longer, thereby improving overall therapy effectiveness.