M-11: Contemporary Trends and Issues in Medication Non-Adherence: A Systematic Review
University of British Columbia Canada
The World Health Organization has declared medication non-adherence an epidemic. Our objective was to conduct a systematic review of the research on medication non-adherence in the past 20 years, in order to identify contemporary trends and issues.
ORAL PRESENTATION: 10:50AM
We conducted a systematic literature search to identify original studies that described/reported/measured medication non-adherence, the burden of medication non-adherence on the individual and the healthcare system and studies that investigated adherence interventions.
We searched MEDLINE, EMBASE, CINAHL and SPORTDiscus for original research studies. We identified 23,330 medication adherence publications since 2000. Our search results showed an increasing trend in number of studies reporting non-adherence over time, with medication non-adherence to chronic medications reported in half of patients in western countries and two thirds of patients in developing countries. In addition to the detrimental consequence non-adherence has on the individual’s disease progression, estimates show that the cost of non-adherence in the United States is approximately $290 billion, equating to about 13% of total health care spending, or 2.3% of GDP. Our review informed issues and trends in five topical areas: HIV, elderly patients, pediatric patients, mental health, and digital health technologies. Medication adherence interventions reported included a simplified medication regimen, phone call follow-up, special reminder pill packaging and counseling; studies reported inconclusive results. Digital health technologies offer a promising solution but research is still emerging and there is need for evidence-based approaches for their development and evaluation. Non-adherence to HIV treatment was reported to range between 17-63% of patients worldwide, with approximately 50% of non-adherence in North America. In the elderly population non-adherence has been reported to range around 70%. In the pediatric population, non-adherence has been reported to range between 30-70%. Under “mental health” one can include several disorders, yet they all share high non-adherence rates and discontinuation rates. For example, data on patients with depression reveal that between 30% and 60% are not adhering to antidepressant therapies.
This systematic review highlights that medication non-adherence continues to be an important problem across patient populations. We observed an increase in the number of original studies over time, likely reflecting the consideration of the importance of this health problem and the urgent need to address it. Non-adherence to medication is common and depending on disease type and population has ranged between 17-85%. These numbers are alarming, as medication non-adherence has substantial impact on the individual’s health and disease progression as well as implications on the healthcare system, with increased cost of treatment and healthcare service utilization for disease complications which could have been prevented if treated appropriately early in the course of the disease. In our review we noted several groups who are at high risk for non-adhering to therapy: HIV patients, elderly, pediatric patients and mental health patients. Reported reasons for non-adherence to therapy in those populations included multiple medications, medications with complex regimens, adverse events/adverse drug reactions, multimorbidity and patients with cognitive decline or an altered mental state. These should be addressed by the healthcare team when prescribing a medication regimen, as some can be prevented or reduced. Different intervention approaches have been reported in the literature, with inconclusive results. However, it has been suggested that a simplified and clear medication regimen that is customized for the patient’s lifestyle will reduce non-adherence. The use of technology to reduce medication non-adherence is emerging and has shown tremendous potential in revolutionizing the way people take their medications.