The Problem of Medication Non-Adherence
Taking medications is a routine for most Americans; nearly three of five American adults take at least one daily medication, and, from 2000 to 2012, the proportion of people taking five or more prescription medications doubled. But for many Americans, taking their medications according to their health care provider’s instructions is a challenge. About half of patients with chronic diseases don’t take their medication as prescribed.
Medication non-adherence has important health consequences, ranging from decreased quality of life and poorly managed symptoms to death. But the implications of medication non-adherence extend beyond the individual; non-adherence is also associated with significant societal costs. Upwards of $300 billion of avoidable health care costs have been attributed to medication non-adherence annually in the U.S., comprising up to 10% of total health care costs.
In this article, we highlight the challenges associated with medication non-adherence, describe the potential factors that contribute to this public health problem, and explore possible solutions that will help us to move the needle toward greater medication adherence.
Three Processes of Adherence: Initiation, Implementation, Discontinuation
There are three distinct processes related to medication adherence, with multiple points along the path where adherence can break down. The first process is initiation, when the patient takes the first dose. The second process is implementation — that is, how well the patient’s actual dosing regimen (e.g., taking the medication as directed from the first dose until the last dose) matches what was prescribed by the provider. The final process is discontinuation, when a patient stops taking the medication for any reason, either with or without the guidance of their health care provider. When medication adherence is viewed according to this taxonomy, we can consider factors that influence how patients will or will not take medications as prescribed.
Factors Contributing to Non-Adherence
Medication adherence is influenced by many factors, including social and economic factors; patient’s perceptions, motivations, and levels of physical/cognitive impairment; issues related to the specific medication therapy; the medical condition being treated; and the health care system in which the person seeks care. While we have many proven tools and strategies to promote optimal medication adherence, each patient and situation is unique.
Social and Economic Factors
Social and economic factors such as poverty, transportation challenges, medication costs, and inadequate insurance coverage are also drivers of medication non-adherence.
For most people, common factors that impact the ability to use medication optimally include forgetfulness, beliefs about medication, and low health literacy. Medication labels are infamously confusing, with instructions such as “Take 1 pill by mouth every 12 hours” or “Take 1 tablet by mouth twice daily,” which describe the same dosing information. Unfortunately, reading prescription labels is particularly challenging for the approximately 77 million Americans who have only basic health literacy. Coupling low health literacy with poorly standardized medication labels produces a recipe for suboptimal adherence.
The unique characteristics of different medication therapies (e.g., the frequency and timing of doses, the number of medications required, associated side effects, etc.) also can influence suboptimal adherence. Because it can be challenging for a patient to organize taking different medications at different times of day, particularly if the medications carry different requirements (e.g., “Take with food,” “Take on an empty stomach,” etc.), the use of more than three medications by the same patient (also known as polypharmacy) is a major barrier to adherence.
Condition-related factors, including concerns related to the stigma of a disease or a condition (e.g., a major depressive disorder) whose attributes make managing routine behaviors challenging, are also closely linked to non-adherence.
Health Care System–Related Factors
Finally, health care system–related factors related to adherence or non-adherence include the accessibility of health care services, differences in the way providers communicate with their patients, the therapeutic relationship between patients and their health care providers, and the integration of pharmacy services (including the availability of electronic prescribing).
Solutions for Enhancing Adherence Through Patient Engagement
Predictive Analytics, Electronic Medical Records Data, and Patient Reported Outcomes (PROs)
Engaging patients in their health is of critical importance. From the perspective of health care professionals, including pharmacists and other clinicians, proactively screening patients for potential problems related to medication adherence may be an initial step toward enhancing medication use. With use of predictive analytics and integrated data systems, the ability to identify patients who are at risk for medication non-adherence on the basis of past behaviors and personal characteristics is increasingly available.
Expanding this effort to collect patient-reported outcomes (PROs), such as real-time symptoms and perceptions of medications, is a crucial next step in the evolution of data systems to improve population health. The combination of predictive analytics, electronic medical records data, and PROs will allow for the efficient allocation of resources to the right patients at the right times. For example, investigators at Duke University are combining medical records data and PROs to identify and personalize an intervention to improve adjuvant endocrine therapy (AET) among women with breast cancer. In this ongoing trial, 400 women who are taking AET are being randomized to a general health education program or an intervention involving a combination of phone calls, tailored interactive voice messaging based on information exchanged during phone sessions, and real-time adherence data obtained from wireless smart medication bottles.
Additional solutions to enhance medication adherence through engagement often require the use of a customized “tool box” that combines different approaches. Fundamentally, for patient engagement to occur, it is essential to evaluate and build patient knowledge, support patient self-monitoring, and increase access to medication through cost reduction.
Improving Adherence During Each Process
The reasons for medication non-adherence are multidimensional. During the initiation process, for example, one reason for non-adherence might be the failure to pick up a medication at the pharmacy, resulting in the patient never taking the medication; thus, solutions during this process often need to focus on educating the patient on the purpose of the medication, explaining the reasons why the medication is prescribed, discussing how the medication should be taken, and alerting the patient about the potential problems or side effects that should be anticipated.
During the implementation process, the patient may struggle with remembering to take medications daily, perhaps causing the patient to take an inappropriately delayed dose, to take an unscheduled medication holiday, or to inadvertently take an extra dose. Solutions during this process may involve calendars, phone reminders, and the use of pill boxes. During the discontinuation process, adherence can be increased by ensuring timely medication refills and explaining the importance of long-term medication use, particularly when the disease or condition being treated is asymptomatic.
Developing a Person-Centered Approach to Increase Adherence
Evidence increasingly demonstrates that adopting a person-centered approach for medication use that incorporates patient beliefs, preferences, goals, and barriers to medication-taking (e.g., cost, technological ability, concerns about medication prescribing and use) leads to better clinical outcomes. Because each person has unique health needs, it is essential for us to engage patients in their health and health care by asking what challenges they face. Doing so enables us to match patients’ medication adherence needs with specifically tailored tools and strategies. As payment and delivery system models evolve to emphasize value and hold health care systems accountable for patient outcomes and costs, the need to include an assessment of medication adherence and tailored strategies to address non-adherence will improve patient-centered care and return on investments.
Creating a Customized Toolbox to Improve Patient Well-Being
There is no universal solution to improve adherence. However, growing evidence suggests that combining approaches that are tailored to address a patient’s specific adherence barriers or challenges may equip patients with the understanding and tools they need to successfully engage in medication adherence. Numerous factors contribute to non-adherence, and there is a need to create a toolbox with various solutions tailored to each stage of adherence. The ability to tailor programs to address an individual’s needs is required to improve medication adherence and ultimately improve patient well-being.