The Effectiveness of Medication Adherence Interventions

An examination of nearly 200 medication adherence trials found that it is actually difficult to determine whether or not the approaches truly worked.

A review published in the Cochrane Library examining data from some of the best trials testing approaches to increase medication adherence and patient health determined most trials had design flaws.

The trials studied a range of medical conditions and numerous different interventions for increasing medication adherence. Typically, only half of patients prescribed medications actually take them as prescribed.

“Across the body of evidence, effects were inconsistent from study to study, and only a minority of lowest risk of bias [randomized control tests] improved both adherence and clinical outcomes,” the authors determined. “Current methods of improving medication adherence for chronic health problems are mostly complex and not very effective, so that the full benefits of treatment cannot be realized.”

Just 17 of the total 182 trials analyzed were of high quality. These 17 trials combined several approaches, such as support from family members or pharmacists, education, and counseling. Just 5 of the 17 improved health outcomes and adherence.

“This review addresses one of the biggest challenges in healthcare, it’s a real surprise that the vast amount of research that has been done has not moved us further forward in our understanding of how to address this problem,” David Tovey, MD, editor-in-chief of the Cochrane Library, said in a statement. “With the costs of healthcare across the world increasing, we’ve never needed evidence to answer this question more than we do now.”

Among the 5 trials that improved health outcomes, there were no common interventions apparent. According to the authors, even the most effective interventions did make large improvements in outcomes or adherence.

A database of the relevant trials is now available to other researchers in the field to encourage collaboration and in-depth analyses.

"By making our comprehensive database available for sharing we hope to contribute to the design of better trials and interventions for medication adherence," lead researcher Robby Nieuwlaat of the Department of Clinical Epidemiology and Biostatistics at McMaster University, in Hamilton, Canada, said in a statement. "We need to avoid repeating the painful lessons of adherence research to date and begin with interventions that have shown some promise, or at least have not produced repeatedly negative results."