Low medication adherence rates of up to 50% are a serious medical and health economic problem. Whether innovative strategies from the behavioral economics environment can improve adherence rates in chronic diseases is discussed in this article.
Adherence - Definition
Adherence stands for the measurable adherence to a medical therapy that has been agreed with the treating physician. If the therapy, especially the medication, is taken exactly as long and as often as agreed, the adherence is 100%. If the therapy was not followed on any day or if the medication was never taken, the rate is 0%. A patient who takes a therapy only every second day instead of every day is 50% adherent. In general, it is assumed that only very few patients are 100% adherent.
Low adherence - a multidimensional problem
Patients who are not adherent or who have a reduced adherence rate are consequently longer and more sick and recover less quickly. Disease-related burden of illness - especially in chronic diseases - is greater in non-adherent patients than in adherent patients. Non-adherent patients cause higher direct and indirect costs (medical and non-medical) and thus impose an additional burden on the healthcare budget. Finally, non-adherent patients increase the personal burden of disease, reduce the quality of medical care and negatively impact the national economy.
The reasons for nonadherence are diverse and vary within cultures, nations, educational classes, genders, indications, and ages (Lee et al. 2018).
Dimensions and consequences of nonadherence
In an older report, the World Health Organization estimated that across all indications, the average adherence rate worldwide is about 50% (Sabaté et al. 2003). This remarkably low figure means that, on average, only half of each therapy is followed correctly. Our research with published data from the western world results in a similar dimension: for example, we find an average medication adherence rate of 64% for hypertension (Durand et al. 2017), 56% for hypercholesteremia (Hope et al. 2019), 62% for diabetes (Krass, Schieback, and Dhippayom 2015), and 50% for depression (Semahegn et al. 2020).
The medical and economic consequences of a 50% adherence rate in chronic diseases are difficult to quantify. However, several papers identify a direct significant association between non-adherence and worsened clinical and health economic outcomes (COPD (van Boven et al. 2014); schizophrenia (Sun et al. 2007); diabetes (Capoccia, Odegard, and Letassy 2016); depression (Ho et al. 2016); and cardiovascular disease (Bitton et al. 2013)).
Behavioral insights provide solutions
A recent systematic review found that behavioral economic methods can improve low adherence rates (Roseleur et al. 2019). In a literature search, the authors found 34 studies that examined adherence improvement in chronic disease using strategies based on behavioral economic insights (BI).
Of the 34 studies selected, 28 were randomized controlled trials, while six studies had a different design. In 18 studies, BI interventions showed a statistically significant effect - this was mainly in the indications CV/diabetes and HIV. 6 studies could show a positive effect only in subgroups. In ten studies, no improvement in adherence rates was observed.
The 18 studies with a positive outcome mainly show that "financial incentives", "reminders and /or feedbacks" as well as "counseling/coaching" are successful BI interventions to significantly improve the adherence rate in the indications CV/diabetes and HIV. Also noteworthy is the fact that BI strategies can sometimes fail. This illustrates that strategies must always be tested for effectiveness before a large roll-out.
Outlook - What needs to be done?
The problem is recognized: Adherence in chronic diseases is generally low. Non-adherence increases factors such as disease-related burden of illness, morbidity, mortality and health care costs. Innovative approaches derived from behavioral psychology (behavioral insights) can improve low adherence rates.
If you or your organization would like to address improving adherence rates in chronic disease, we would be happy to use our expertise to help you analyze the situation and develop powerful strategies to solve the problem. Please do not hesitate to contact us.
Bitton, Asaf, Niteesh K. Choudhry, Olga S. Matlin, Kellie Swanton, and William H. Shrank. 2013. “The Impact of Medication Adherence on Coronary Artery Disease Costs and Outcomes: A Systematic Review.” The American Journal of Medicine 126 (4): 357.e7-357.e27.
Boven, Job F. M. van, Niels H. Chavannes, Thys van der Molen, Maureen P. M. H. Rutten-van Mölken, Maarten J. Postma, and Stefan Vegter. 2014. “Clinical and Economic Impact of Non-Adherence in COPD: A Systematic Review.” Respiratory Medicine 108 (1): 103–13.
Capoccia, Kam, Peggy S. Odegard, and Nancy Letassy. 2016. “Medication Adherence With Diabetes Medication: A Systematic Review of the Literature.” The Diabetes Educator 42 (1): 34–71.
Durand, Hannah, Peter Hayes, Eimear C. Morrissey, John Newell, Monica Casey, Andrew W. Murphy, and Gerard J. Molloy. 2017. “Medication Adherence among Patients with Apparent Treatment-Resistant Hypertension: Systematic Review and Meta-Analysis.” Journal of Hypertension 35 (12): 2346–57.
Ho, Siew Ching, Huey Yi Chong, Nathorn Chaiyakunapruk, Balamurugan Tangiisuran, and Sabrina Anne Jacob. 2016. “Clinical and Economic Impact of Non-Adherence to Antidepressants in Major Depressive Disorder: A Systematic Review.” Journal of Affective Disorders 193 (March): 1–10.
Hope, Holly F., George M. Binkley, Sally Fenton, George D. Kitas, Suzanne M. M. Verstappen, and Deborah P. M. Symmons. 2019. “Systematic Review of the Predictors of Statin Adherence for the Primary Prevention of Cardiovascular Disease.” PloS One 14 (1): e0201196.
Krass, I., P. Schieback, and T. Dhippayom. 2015. “Adherence to Diabetes Medication: A Systematic Review.” Diabetic Medicine : A Journal of the British Diabetic Association 32 (6): 725–37.
Lee, Shan-Qi, Aravind Sesagiri Raamkumar, Jinhui Li, Yuanyuan Cao, Kanokkorn Witedwittayanusat, Luxi Chen, and Yin-Leng Theng. 2018. “Reasons for Primary Medication Nonadherence: A Systematic Review and Metric Analysis.” Journal of Managed Care & Specialty Pharmacy 24 (8): 778–94.
Roseleur, Jacqueline, Gillian Harvey, Nigel Stocks, and Jonathan Karnon. 2019. “Behavioral Economic Insights to Improve Medication Adherence in Adults with Chronic Conditions: A Scoping Review.” The Patient 12 (6): 571–92.
Sabaté, Eduardo. 2003. “Adherence to Long-Term Therapies : Evidence for Action. World Health Organization.” World Health Organization.
Semahegn, Agumasie, Kwasi Torpey, Adom Manu, Nega Assefa, Gezahegn Tesfaye, and Augustine Ankomah. 2020. “Psychotropic Medication Non-Adherence and Its Associated Factors among Patients with Major Psychiatric Disorders: A Systematic Review and Meta-Analysis.” Systematic Reviews 9 (1): 17.
Sun, Shawn X., Gordon G. Liu, Dale B. Christensen, and Alex Z. Fu. 2007. “Review and Analysis of Hospitalization Costs Associated with Antipsychotic Nonadherence in the Treatment of Schizophrenia in the United States.” Current Medical Research and Opinion 23 (10): 2305–12.