Keys to drug compliance may be trust and pill shape

Patients who give their physicians low grades are likelier to have lapses in drug adherence, said a study of nearly 10,000 Northern California patients with diabetes.

Thirty-nine percent of patients who said they never or only sometimes have confidence in their primary care physicians skipped their cardiometabolic medicines at least 20% of the time, the study said. That is a nonadherence rate 11 percentage points higher than for patients who said they usually or always trust their doctors.

Similar drug compliance gaps were found for patients who said their doctors did not involve them in decisions or understand their problems with treatment, or put the patient's needs first, said the study (link).

The findings shed light on the critical role the patient-physician relationship plays in achieving the optimal drug compliance essential to attaining treatment goals, said Neda Ratanawongsa, MD, MPH, lead author of the study, which was published online Dec. 31, 2012, in Archives of Internal Medicine, now JAMA Internal Medicine.

“We have it in our minds as physicians that forming relationships is why we went into medicine,” said Dr. Ratanawongsa, an assistant professor in the Dept. of Medicine at the University of California, San Francisco, School of Medicine. “And it's important to patients, and it makes an impact in the long run on their ability to take their medicines and take care of themselves.”

It is not enough for doctors to make the correct diagnosis and prescribe the right treatment, said Dr. Ratanawongsa, who practices at San Francisco General Hospital. Physicians also should encourage patients to ask questions about their medications and discuss financial and other barriers to adherence. Earning the confidence of some patients can be difficult, but making the effort is worth it, she said.

“It's an investment up-front, and it may take time to gain trust with people,” she said. “I want to be able to leave a session with a patient saying I made an impact, and that what I said mattered, and how I listened mattered. It's a difference in how we think about communication.”

Drug appearance affects adherence

The patient-physician relationship is only one factor in noncompliance, experts say. Others include out-of-pocket costs, the complexity of drug regimens and patient misunderstandings about the role of their medications. Another study in the same issue pinpointed a less obvious culprit: a pill's shape, size and color.

Patients who skipped their antiepileptic drugs were 27% likelier to have recently had a switch in medication that resulted in the pill's having a different appearance. In the study of more than 60,000 patients, the antiepileptic drugs dispensed to patients came in 37 colors and four shapes. Whether switching from a brand drug to a generic, or from one generic to another, the disruption can confuse some patients, said the study (link) .

To avoid patient mix-ups, the Food and Drug Administration should require that generic and branded versions of drugs have the same appearance, said Aaron S. Kesselheim, MD, MPH, the study's lead author and an assistant professor of medicine at Harvard Medical School in Boston.

In the meantime, doctors should address any patient apprehensions about generic drugs, he said.

“Physicians need to be aware that this might be a factor in their patients' nonadherence and be sure to educate patients that despite the fact that the pills might change in their physical characteristics, that all generic drugs approved by the FDA as bioequivalent have the same clinical impact as the brand drug and are equally effective and safe,” he said.