Study reviews medication adherence interventionsJan. 10, 2013, 8:57 AM
According to a medical literature review published last month in the Annals of Internal Medicine, approximately 50 percent of medications for chronic disease are not taken as prescribed.
Failure to take prescribed medications was estimated to cause 10 percent of hospitalizations and 125,000 deaths annually. The total cost to the U.S. health system from poor medication adherence was put at $100 billion to $289 billion per year.
A randomized clinical trial led by Sunil Kripalani, M.D., M.Sc., associate professor of Medicine, published recently in the Journal of General Internal Medicine, casts a spotlight on a couple of interventions commonly used to assist medication adherence.
The researchers found that sending patients monthly postcard reminders to refill their prescriptions was ineffective. Also, providing patients individualized, illustrated daily medication schedules did not significantly raise adherence overall. But the study also found that illustrated medication schedules doubled adherence among certain patient subgroups.
The Atlanta-based study group included 440 inner-city residents with coronary heart disease; 124 patients were given individualized illustrated daily medication schedules; another 103 patients were sent monthly postcards reminding them to refill specific prescriptions; a third group of 117 patients received both of these interventions; and a control group of 96 patients got usual care, receiving neither the medication schedules nor the reminder postcards.
Patients already receiving daily assistance with medication management were not eligible.
The group was 91 percent African-American. The median number of medications prescribed to patients in the study was eight (the range was seven to 10).
Adherence was tracked for one year based on pharmacy refill records, a method that is considered to be a validated surrogate for more direct monitoring (all patients attested to using the same pharmacy exclusively).
Adherence, defined in this study as refilling at least 80 percent of medications as prescribed, was quite low overall, ranging from a high of 37 percent among patients who got both the illustrated schedules and the reminder postcards, to a low of 28 percent among patients who got only the postcards. Adherence among the control group was 31 percent.
Statistically, adherence among the study group as a whole was not significantly improved by either intervention, nor by the combination of the two interventions.
However, the illustrated medication schedules were associated with doubled adherence among patients with a more complex regimen (nine or more medications), and among patients who, in a survey taken at the start of the study, were found to have lower-than-average confidence in their ability to take their medications correctly.
It makes sense to Kripalani that different subgroups would be differently affected by these adherence interventions.
“The underlying causes of poor medication adherence vary tremendously and include such things as costliness, low health literacy, side effects, forgetfulness, regimen complexity and other causes, so a one-size-fits-all solution should not be expected,” he said.
“Approaches to support safe and effective medication use should be tailored to patients’ individual barriers. We were able to identify some at-risk groups that may benefit from using an illustrated schedule.”
This research was supported by a grant from the American Heart Association.