Multiple factors contribute to the decision not to take osteoporosis medications, with fear of adverse events topping the list, say researchers in a paper published online in the Journal of the American Pharmacists Association.

In the study, researchers collected information about 790 participants in the Patient Activation After DXA Result Notification study who had received prescriptions for new or different osteoporosis medications after a dual-energy X-ray absorptiometry scan. Participants were interviewed at baseline and 12 and 52 weeks after their DXA scans, and researchers collected information such as patient demographics, health history, health habits, prior osteoporosis diagnosis or treatment, osteoporosis knowledge using the “Osteoporosis and You” scale, osteoporosis health beliefs, and osteoporosis self-efficacy.

At the 12-week interview, 196, or 24.8%, of the participants reported that they did not start the newly prescribed treatment for their condition. When asked why they did not take their medications, 46 (23.4%)  stated reasons to indicate that their nonadherence would be temporary, such as waiting to see if the medication would be covered by their insurance. The remaining 150 (76.6%) decided not to take their medication at all. Furthermore, at 52 weeks, fewer than half of the temporary nonadherers had actually started taking their osteoporosis medication.

The most common reasons participants gave for not taking osteoporosis medications were fear of adverse effects or contraindications, a dislike of taking medications, and a belief that taking medication wouldn’t improve their condition. When the researchers reviewed the data from the participants’ interviews, they also found that those who had the greatest understanding of osteoporosis were less likely to take their medications. In their discussion, the researchers note that temporary nonadherers may have understood the role of lifestyle changes in preserving bone health, and patients who had self-efficacy for exercise as a way of slowing bone loss may have tried to make those changes instead of taking medications.