- Antidepressant adherence has been shown to improve health outcomes and reduce workplace costs.
- We calculated antidepressant adherence rates using the Healthcare Effectiveness Data and Information Set (HEDIS) acute and continuation phase treatment measures in a nationwide dataset (n = 5,648).
- We found that only 49% and 31% of patients were adherent in the acute and continuation phase, respectively.
- Patients with severe depression had lower rates of adherence, while adherence by antidepressant type was dependent on depression severity.
- Given the reduction in adherence from the acute to continuation phase, improved continuity of care and patient-provider communication may help reduce disease burden.
Over 300 million people worldwide, or 4.4% of the world’s population, suffer from depressive disorders.1 As the number one cause of worldwide disability, depression causes substantial impairment, reduced quality of life, and decreased productivity.2,3 The two modalities of treatment for major depressive disorder (MDD) include antidepressant-based pharmacotherapy and psychotherapy.
Adherence to antidepressant treatment has been shown to improve health outcomes and reduce workplace costs.4-7 For example, Burton et al. (2007) found that employees who were non-adherent to treatment recommendations that followed the Healthcare Effectiveness Data and Information Set (HEDIS) guidelines were 38.7% and 46.1% more likely to have work absence claims in the acute and continuation phases of treatment, respectively, than adherent patients.4 However, the authors could not test for adherence by depression severity or antidepressant type.
In this research brief, adherence to HEDIS antidepressant treatment measures was evaluated for patients newly diagnosed with MDD by depression severity and antidepressant type.
We used Truven’s MarketScan® Commercial Claims and Encounters database from 2007 to 2015 and selected for patients newly diagnosed with MDD and antidepressant prescriptions. The HEDIS’s metrics for antidepressant adherence in the acute and continuation phase of treatment, developed by the National Committee for Quality Assurance (NCQA), were used. For the acute phase, adherence was determined as at least 84 days of continuous antidepressant treatment during the 114-day period following the first prescription date.8 For the continuation phase, adherence was determined as at least 180 days of continuous antidepressant treatment during the 231-day period following the first prescription date.8
There were 5,648 patients with newly diagnosed MDD in our dataset, in which 49% and 31% were adherent in the acute and continuation phase of treatment, respectively (Table 1). Patients with a first depression diagnosis categorized as “severe” were less adherent in the acute (43.2%) and continuation phases (27.8%) than those diagnosed with “mild” or “moderate” depression (51.1% and 32.6%, respectively; chi-squared p-values < 0.001). When we further divided our population by antidepressant type (Table 2), patients who were prescribed selective serotonin reuptake inhibitors (SSRI) or norepinephrine-dopamine reuptake inhibitors (NDRA) typically had higher adherence in the acute phase and chronic phase. However, adherence rates by antidepressant type were dependent on the severity of depression.
Given the low rates of adherence and the large drop in adherence from the acute to continuation phase, our findings suggest that all patients with depression may benefit from improved continuity of care and patient-provider communication.
Future research will investigate treatment pathways, prevalence of psychotherapy, and the association of antidepressant adherence on work disability, hospital admissions, and medical costs.
About the Author
Dr. Fraser Gaspar is an Epidemiologist with MDGuidelines at ReedGroup since 2016. His research focuses on the factors that influence a patient’s successful return to activity and the use of evidence-based treatment guidelines in improving health outcomes. Dr. Gaspar completed his PhD and MPH at University of California Berkeley’s School of Public Health in Environmental Health Sciences.
- World Health Organization. Depression and other common mental disorders: global health estimates. World Heal Organ. 2017:1-24. doi:CC BY-NC-SA 3.0 IGO.
- Kessler RC, Berglund P, Demler O, et al. The Epidemiology of Major. JAMA. 2003;289(23):3095-3105.
- Henderson M, Hotopf M. Work and common psychiatric disorders. 2011:198-207.
- Burton WN, Chen C, Conti DJ, Schultz AB, Edington DW. The Association of Antidepressant Medication Adherence With Employee Disability Absences. Am J Manag Care. 2007;13(2):105-112.
- Chisholm D, Sweeny K, Sheehan P, et al. Scaling-up treatment of depression and anxiety: A global return on investment analysis. The Lancet Psychiatry. 2016;3(5):415-424. doi:10.1016/S2215-0366(16)30024-4.
- Katon WJ, Seelig M. Population-Based Care of Depression: Team Care Approaches to Improving Outcomes. J Occup Environ Med. 2008;50(4):459-467. doi:10.1097/JOM.0b013e318168efb7.
- Birnbaum HG, Ben-Hamadi R, Kelley D, et al. Assessing the relationship between compliance with antidepressant therapy and employer costs among employees in the United States. J Occup Environ Med. 2010;52(2):115-124. doi:10.1097/JOM.0b013e3181cb5b10.
- National Committee for Quality Assurance (NCQA). HEDIS 2015: Healthcare Effectiveness Data and Information Set. Vol 1. Washington, DC; 2014.