Self-Reported Medication Adherence Rates Among Diabetes Patients Vary Greatly from NP Observations

Poor medication adherence habits constitute a major threat to public health and costs the United States between $100 billion and $289 billion annually.

A recent study published inBMJ Open Diabetes Research & Carerevealed a significant disconnect between self-reported medication adherence rates from high-risk type 2 diabetes (T2D) patients compared with what’s observed and documented by a nurse practitioner (NP).

Researchers analyzed data from 430 adults with T2D at high risk for serious adverse events or death. Everyone in the cohort participated in the Southeastern Diabetes Initiative (SEDI), which consists of a home visit, physician assessment, survey, and direct observation of pill bottles and insulin administration.

“High risk” in this study was defined by the following factors: recent hospitalization, substance or tobacco use, or having multiple comorbidities that require multiple medications, such as chronic kidney disease, heart failure, hypertension, or coronary artery disease.

The self-reporting tool employed by this study was the Morisky Medication Adherence Scale (MMAS), a questionnaire administered by an NP that asks patients to recall their own medication adherence and other health behaviors. The authors noted that the MMAS has been shown to be a reliable measure among other patient populations. For example, previous research on patients with hypertension has shown a strong correlation between MMAS-measured medication adherence and blood pressure control.

In the case of high-risk T2D patients, however, the investigators believed that the MMAS lacks sensitivity to the number of comorbidities and associated medication regimens that often develop in T2D patients.

“In SEDI, factors that classified patients as high risk included recent hospitalizations, substance use, tobacco use and multiple comorbidities—including coronary artery disease, hypertension, heart failure or chronic kidney disease—all of which require complex medication regimens,” wrote Katherine Kelly, FNP, of the Duke University Health System, and colleagues. “As a result, patients may report that they are ‘getting enough medications’ daily, skewing self-reported results and suggesting that improvement in diagnostic measures is needed, particularly in illnesses with multiple comorbidities.”

Beyond medications, patients with T2D may have trouble accurately measuring their medication adherence habits because of the number of behavioral factors they need to recall, including food intake, glucose levels, activities, or times of day.

“Regardless of the underlying reasons for lack of agreement between self-report and observed counts, every effort must be made to discover where, in this high-risk population, the breakdown occurs,” the authors concluded.

With the prevalence of TD2 increasing to almost 10% of the total US population, it is of great importance that patients and NPs alike reconcile differences in measuring and recalling medication adherence habits.

Treatment adherence problemsare commonin patients with T2D because they may look and feel perfectly fine. It may be hard to fathom that they have a serious disease that can cause significant problems in the future. Sometimes, patients do not understand that many of these comorbidities can be better managed or even eliminated by adhering to treatment plans.

For instance, clinicians can consider the volume and frequencies of a patients’ prescription fills and not rely entirely on self-reports of medication adherence. Overall, a clinician’s role in counseling patients should be to (1) ensure that they have sufficient understanding, knowledge, and skill to follow their regimens and monitoring plans, and (2) motivate patients to take an active role in their health care.