Study authors Derjung M. Tarn, Thomas J. Mattimore and Neil S. Wenger of the University of California, Los Angeles; Douglas S. Bell of UCLA and the RAND Corp.; Richard L. Kravitz of University of California, Davis, and colleagues conducted focus-group discussions with providers and recorded out-patient office visits with 100 patients taking a total of 410 medications.
They also examined how adherence discussions were initiated between healthcare providers and patients.
The study, published in the Journal of the American Geriatrics Society, found that providers felt responsible for assessing and addressing adherence but believed patients were ultimately responsible.
The researchers also found that physician–patient interactions were conducted in a way that might address adherence for 62 percent of the 410 medications; these interactions included simple inquiries about adherence for 31.5 percent of the medications but in-depth questions about adherence for only 4.3 percent of the medications.
Patients spontaneously disclosed their non-adherence in 51 percent of 39 identified instances of non-adherence, the study said.
The study also found patients' non-adherence to prescribed medication costs the U.S. healthcare system an estimated $290 billion annually and can lead to poor clinical outcomes, increased hospitalizations and higher mortality.