The Power of Medication Adherence Packaging
The Problem.
Determinants and causes for non-adherence
Various aspects of medical care and personal experience can cause people to not adhere to their medications.
Presence of chronic diseases
A common determinant of adherence is the presence of chronic diseases. Chronic diseases, such as hypertension, may be asymptomatic, meaning patients do not feel sick. Additionally, many drugs for chronic diseases are not curative and are instead aimed at prevention or treatment. With this, patients may neither understand the importance of adherence, nor remember to take their medications. This explains why 63% of individuals taking preventative treatment were compliant versus 77% of individuals taking curative treatment1.
Adherence Rates for Preventative vs. Curative Treatments Differ
Polypharmacy is the use of five or more medications daily – and it's a leading cause of non-adherence.
Chronic disease also often occurs comorbidly with other conditions, causing many individuals to be on multiple drugs at once. Polypharmacy, which refers to the use of over five medications daily, can be an indicator for non-adherence. Balancing numerous medications with different timings and routes of administration can be confusing to the patient. Often, complex or numerous medication regimens can lead patients to forget doses, take them late, or take too many at once.
Health literacy
Likewise, health literacy is a major factor that influences a patient’s level of compliance. Health literacy refers to an individual’s ability to read and comprehend medical instructions. Those with low health literacy may have trouble interpreting their prescription instructions. Thus, they may not adhere to their medication regimens as directed. In one study, over 60% of individuals misunderstood their provider’s directions immediately after their office visit1.
Over 60% of people misunderstand their clinician's directions immediately after their office visit.
Indicators of
non-adherence
Polypharmacy (5 or more daily medications)
Health literacy
Misunderstanding
Side effects
Cost
Demographics
Cognitive decline
Older adults have an average adherence rate of 45%.
Side Effects
Other issues causing non-adherence include misunderstandings surrounding treatment. For example, patients might not understand the need for treatment, or worry about side effects. Some patients who experience side effects may discontinue treatment themselves without consulting their doctor, and without their doctor’s consent.
Affordability
Patients may struggle to pay for their medications or may not have insurance to support payment. Some insurance programs can also make coverage difficult, whether through high deductibles, administrative burden or long waiting periods for processing.
Medication affordability remains a significant barrier to medication adherence, with studies finding higher copays are a strong predictor of treatment failure6. Likewise, elimination of co-pays for medications that treat chronic illnesses was associated with increases in medication adherence and reductions in overall spending7.
Surveys have also found almost 8% of US adults did not take medications to save money, while 15.1% asked their doctor for a lower-cost medication8.
Demographics
Other predictors of adherence relate to patient demographics. Age, sex, income, education level, marital status, and personality can all contribute to non-compliance. For example, older adults tend to have lower adherence rates, with an average adherence rate of 45%. While aging and cognitive decline may contribute to this low adherence level, it may also be the result of polypharmacy, which is common in older patients1.
Impacts of non-adherence.
Numerous studies have analyzed how medication adherence affects clinical outcomes, primarily relying on patient self-reporting and pharmacy refill data to understand adherence patterns.
In general, non-adherence negatively impacts patient outcomes and increases risk of death. Non-adherence to cardiovascular drugs, for example, can help put context to the consequences of poor medication management. With many of these medications, a lack of compliance correlates with morbidity and mortality.
Statins are a common cardiovascular drug class aimed at lowering lipid levels. In patients taking statins, up to 50% of patients will stop therapy within a year of starting their prescription. By the two-year mark, non-adherence rises as high as 75%. To analyze the effects of statin non-adherence, a study evaluated patients on statin therapy one year after hospitalization for heart attack. Patients who were not adherent to their statin had a 25% greater risk of death compared to adherers9,10. Another study found that with certain cardiac conditions, poor adherence led to a 10 to 40% increase in hospitalizations. Additionally, poor adherence led to a 50 to 80% increased risk of death9.
Patients who were not adherent to their statin prescription had a 25% greater risk of death.
Another study looked at the impacts of non-adherence to antiplatelet and lipid-lowering drugs. Patients who did not take their medication as directed had an increased risk of heart attack, stroke, and death.
Other research evaluated patients taking clopidogrel after receiving a stent. Patients who did not take their medication as directed had an increased risk of stent thrombosis at six months.
These findings represent the importance of proper use of cardiovascular medications in preventing complications and death. One can also apply these learnings to all medications to help understand the hazards of non-adherence10.
Impacts of Adherence.
As non-adherence leads to poor outcomes, adherence leads to positive outcomes. Consider again cardiovascular drugs, for example, where the clinical impacts of adherence are well-defined. In one study, patients adhering to their blood pressure medication were more likely to have blood pressure control compared to non-adherent individuals. Additionally, with each 25% rise in statin adherence, a consequent 3.8 mg/dL decrease in LDL cholesterol occurred9.
In patients who have high levels of adherence, hospitalization rates are also lower. Hospitalization is the most expensive type of medical cost, thus it is the main driver of cost savings for those who are compliant to their medications11.
When patients take their antidiabetic medications as directed, the likelihood of these complications goes down.
This means outside of better clinical outcomes, adherence has economic benefits for patients and healthcare systems.
In those with high cholesterol and diabetes for example, adherence correlates with less disease-related cost. Uncontrolled diabetes can cause complications such as neuropathy or microvascular disease. When patients take their antidiabetic medications as directed, the likelihood of these complications goes down. Without these complications, the all-cause medical cost associated with diabetes is less.
Another example includes high blood pressure. Blood pressure control can slow the progression of renal disease. Likewise, the costs associated with blood pressure would be less without the presence of renal disease. Adherence, therefore, can reduce healthcare costs for the patient.
