Medication Adherence

A systematic review of the huge number of studies in this area finally has been done.

From time to time in the past few years, I’ve done a literature search on medication adherence and more specifically, non-adherence. As a clinician, I’ve been looking for evidenced-based interventions on how patients’ adherence to their medication regimens can be improved. It’s been daunting, though, because of the enormous number of studies that have been done, and how these studies have been conducted. For instance, there are uncontrolled studies, studies from one institution only, studies with small sample sizes, and studies looking at just one type of medication. The study designs, as well as all of the variables, make interpretation of the data challenging.

Researchers recently published a systematic review of interventions to improve adherence to diabetic and cardiovascular medications. This is a specific target population (patients with diabetes or heart disease), so the study findings shouldn’t be generalized to all populations of patients; however, this is a good first start in reviewing the copious amount of literature out there. The researchers reviewed randomized controlled studies published from 1966 to 2008, and classified studies on the mode of delivery: 1) person-independent interventions that were mailed, faxed, or hand distributed; or delivered via electronic interface; or 2) person-dependent interventions such as non-automated phone calls and in-person interventions. They identified 6550 articles and found 51 that met their inclusion criteria.

Among person-independent interventions (56% successful), electronic interventions were most successful (67%). Among person-dependent interventions (52% successful), phone calls showed low success rates (38%). In-person interventions at hospital discharge were more effective (67%) than clinic interventions (47%). In-person pharmacist interventions were effective when held in a pharmacy (83% successful), but were less effective in clinics (38%).

As the researchers noted, more research needs to be done to identify when patients are most receptive to receiving teaching about their medications. Future studies also need to further examine what types of electronic interventions work better than others. In the meantime, nurses and pharmacists need to continue their one-on-one patient teaching as it is more effective than simply handing a patient an information sheet and sending them on their way.

Reference

Cutrona SL. et al. Modes of delivery for interventions to improve cardiovascular medication adherence. Am J Manag Care. 2010;16(12):929-942.