An Overview of the Challenges, Strategies, and Impact of Medication Adherence

Medication adherence is the extent to which a patient follows provider instructions for medication dosage, timing, and duration of use. This is a collaborative effort between the patient and provider, as opposed to the passive obedience of compliance.

Although medication adherence varies widely by condition and population, it often ranges from 30% to more than 80%.¹ Research has found that medication nonadherence costs $528.4 billion annually in direct and indirect costs.²

Nonadherence to medication regimens is a complex issue involving a combination of patient, provider, and systemic factors. It leads to significantly poorer patient outcomes and greatly increases health care costs.² Addressing this issue is paramount to improving patient outcomes, and solutions must be multifaceted, focusing on improved patient-provider communication, financial assistance, and simplified treatment plans.

Factors Contributing to Nonadherence

Nonadherence to medication regimens can be unintentional or intentional. Unintentional nonadherence often results from forgetfulness or complexity. Intentional nonadherence originates from the patient’s active decision-making process and their understanding of their condition and/or treatment.

Patient-related factors

Forgetfulness often plays a role in nonadherence, particularly for patients who lead busy lives, have complex medication regimens, and/or are in cognitive decline. Conditions such as diabetes and hypertension as well as the use of certain medications can increase the risk of cognitive decline, which is linked to higher rates of medication nonadherence.³

Psychological barriers such as pharmacophobia (fear of medication), fear of adverse events (AEs), mistrust of the health care system, and health anxiety can also contribute to nonadherence. Pharmacophobia can lead to a negative mindset toward drugs and result in avoidance of necessary treatment. Patients also may have personal experience with—or heard about other patients who had— negative reactions to medication, which may influence their feelings.⁴

Inaccurate or incomplete information about a medication’s importance, use, or onset of symptom relief can cause patients to become nonadherent or prematurely discontinue medication use. Mental health conditions also can negatively impact medication adherence due to lack of insight into the illness, fear or shame surrounding the social stigma of mental illness, and cognitive difficulties resulting from anxiety and/or depression.⁴

Patient beliefs also influence medication adherence. Cultural, religious, and personal beliefs about health, traditional medicine, the need for treatment, and the general health care system can hinder medication adherence.⁴

Health care system– and provider-related factors

Medication cost, which can stem from high co-pays or a lack of prescription insurance, is a major factor in nonadherence. These financial barriers can lead to several behaviors such as skipping doses, taking less than prescribed, not filling or refilling prescriptions, and relying on other methods to manage the condition.⁵

Poor communication between patients and health professionals, including pharmacists, may lead to a lack of clarity about the medication. This includes the benefits of the medication, dosing instructions, duration of use, AEs, and administration techniques. Patients are also less likely to adhere to treatment recommendations if their questions and concerns are not fully addressed.⁶

Lack of collaboration between patients and providers also negatively impacts medication adherence. Not involving patients in formulating treatment plans can lead to not addressing potential barriers, misunderstanding, ignoring patient beliefs, and decreased adherence.⁷

Lack of access is a complex issue that also affects medication adherence and is driven by several factors, including cost, location, and systemic challenges that disproportionately affect vulnerable populations.⁸

Medication-related factors

Complex medication regimens can increase nonadherence because patients may have difficulty keeping track of multiple medications. High pill burdens, frequent dosing, and complicated administration instructions contribute to nonadherence.⁹

AEs can also significantly reduce medication adherence and may even result in patients discontinuing a medication. As the severity of AEs increases, so does the rate of nonadherence. Specific AEs such as sleep disturbances, gastrointestinal issues, dry mouth, and weight gain are frequently linked to nonadherence.^10,11

Patients with asymptomatic conditions may lack the motivation to consistently take their medications and become nonadherent. For example, for conditions such as hypercholesterolemia and hypertension, there are no tangible symptoms to physically remind patients to take their medications.¹²

Strategies for Improvement

The most effective strategies for improving medication adherence focus on identifying specific challenges and addressing them collaboratively with the patient.

Create a nonjudgmental, trusting environment in which to counsel patients. This will help encourage open and honest communication. Ask open-ended questions to allow patients to elaborate on their challenges. Ensure patients understand what each medication is for, how to use it, what AEs they may experience, and the consequences of nonadherence. Finally, use the teach-back method to ensure the patient understands instructions.

Leveraging technology to help patients become more adherent is a growing trend—from smartphone apps that send reminders and provide medication information to devices such as smart pill bottles and dispensers that track usage and report back to providers. Additionally, remote monitoring devices can track health metrics for patients with chronic conditions and provide feedback on medication effectiveness.

Because adherence often decreases as the number of daily doses increases, once-daily dosing or an extended-release formulation will often help with this challenge.⁹ If feasible, consolidate dosing times so patients only need to take medication once or twice daily. Using combination medications can lighten the pill burden for patients who find they have too many medications to take, and synchronized refills make for fewer trips to the pharmacy.

Discuss the cost of the medication with the patient. If cost is a significant challenge, explore alternatives such as a generic equivalent, a cheaper medication in the same class, or pharmacy discount programs. Direct patients toward pharmaceutical companies for coupons or to a nonprofit that will help pay for medications.

Conclusion

Medication nonadherence continues to be an ongoing issue that negatively impacts patient outcomes and the health care industry while driving up health care costs and straining health care resources. Although there are a variety of challenges, there are solutions. When these solutions are implemented with patient-centered collaboration, medication adherence improves.

About the Author

Kathleen Kenny, PharmD, RPh, earned her doctoral degree from the University of Colorado Health Sciences Center. She has more than 30 years of experience as a community pharmacist and works as a clinical medical writer based out of Albuquerque, New Mexico.

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