Medication adherence: a challenge for patients with postmenopausal osteoporosis and other chronic illnesses.

OBJECTIVE To define medication adherence and describe the limitations of various assessment methods, reasons for nonadherence to medications used to manage chronic illness, the impact of nonadherence to osteoporosis medications, and strategies for improving medication adherence. BACKGROUND Medication nonadherence is a major public health problem that adversely affects patient outcomes and increases health care utilization and costs. Postmenopausal osteoporosis is a chronic disease, and adherence to drug therapy used to manage the disease is as much of a challenge as it is in other chronic diseases. SUMMARY Medication adherence reflects both compliance and persistence. Direct assessment methods (e.g., observation, laboratory serum drug assays) are more accurate than indirect methods, but they are more costly and often impractical. Indirect methods include patient self-report and the use of prescription refill records, pill counts, and electronic monitoring devices. Medication adherence in patients with postmenopausal osteoporosis or other chronic illnesses is less than optimal. Adverse effects, financial constraints, mis-communication with the prescriber, and a perception that medications are unnecessary are among the possible reasons for medication nonadherence. Unintentional nonadherence is a passive process, often simply forgetting, and intentional nonadherence is an active process involving a deliberate choice, often based on adverse effects or a perceived lack of benefit. CONCLUSIONS Nonadherence to osteoporosis medications can adversely affect patient outcomes and increase health care utilization and costs. An individualized approach to improving medication adherence based on patient preferences and readiness to change is needed.