The effect of antidepressants on patient-reported health-related quality of life

Approximately one out of every five adults in the United States (US) experience some mental illness every year, with depression being the most prevalent. Approximately 17.3 million adults in the US reported at least one major depressive episode in 2017, as per the National Institute of Mental Health (NIMH). Additionally, patients with one or more chronic condition(s) have a high risk of developing chronic depression associated with poor concentration, lack of interest, persistent sadness, and change of mood.

Background

Depression is known to negatively impact these patients’ health-related quality of life (HRQoL), leading to unhealthy or risky behaviors such as overeating, inactivity, smoking, and noncompliance with their medications. The short form (36) health survey (SF-36) reported the significant impact of depression on patients’ HRQoL. The presence of major depressive disorder (MDD) as a comorbidity in patients with other medical conditions can lead to worse HRQoL than in patients with only the medical condition. Hence, screening and treating depression in these patients can improve their HRQoL and reduce the overall medical cost.

Furthermore, depression disorders are reported to put a huge burden on the global and national economies. The cost of managing MDD alone was around US$ 66 billion in 2005, which increased by 21 percent in 2010. A recent estimation of total annual healthcare costs of managing mood disorders showed that the cost of mood disorder patients was double as compared to patients without mood disorders.

The national annual direct increase in healthcare expenditures on mood disorders was approximately $172 billion between 2007 and 2017 in the US. Additionally, direct and indirect costs per year were higher for people with depression, indicating that inadequate treatment of these patients can increase the societal cost of their illness.

The use of psychotherapy and pharmacotherapy was found to help improve the symptoms and quality of life of the patients. A combination of the two methods is found to be more helpful than each method separately. However, the American Psychiatric Association (APA) guideline recommends using either psychotherapy or second-generation antidepressants as initial therapy for adults. Patients with partial or no response to the initial therapy can switch from pharmacotherapy alone to cognitive therapy alone. They can also switch from one antidepressant medication to another antidepressant medication of the same or different class.

Although previous clinical trials suggest that psychopharmacotherapy may improve the clinical outcomes of patients, its overall beneficial effects are controversial. Several meta-analyses indicated that the difference between the placebo and treatment groups of antidepressant medications was minimal. Moreover, psychotherapy and antidepressants were found to have comparable efficacy. Additionally, the effect of psychopharmacotherapy on the overall health of the patients was not evaluated using patient-reported outcome (PRO) measures, such as the HRQoL.

A new study published in PLoS ONE aimed to investigate the effect of using antidepressant medications on the HRQoL of patients with depression.

About the study

The study involved data from the Medical Expenditures Panel Survey (MEPS), a nationally representative database based on self-reported data from families and individuals. Two-year longitudinal data files included data collected between 2005 and 2016. Data on the related medical condition and prescribed medicines files from 2005 to 2015 were also included.

The study included participants who were noninstitutionalized US adults having depression documented in their medical condition files during the first year of the two-year follow-up. Individuals who had completed a two-year follow-up in MEPS with a final person weight greater than zero were included in the study.

After that, data was extracted from the MEPS medical condition files and analyzed. The HRQoL in the MEPS was measured using the SF-12 health survey (version 2). The physical component summary (PCS) and mental component summary (MCS) were reported where PCS focuses on physical functioning, and MCS focuses on social functioning. These components were represented using four variables in MEPS, two baselines (PCS2 and MCS2), and two follow-ups (PCS4 and MCS4) variables, where PCS2 and MCS2 were captured at the beginning of the first year and PCS4 and MCS4 were captured at the end of the second year.

Study findings

The results indicated that throughout the study, approximately 17.47 million adult patients were diagnosed with depression disorder every year with a two-year follow-up. Around 57.6 percent of these patients were found to receive treatment with antidepressant medications, and the average age of the patients was reported to be 48.3 years. Females accounted for more than two-thirds of the sample with 60.6 percent receiving antidepressants compared to 51.5 percent of males. The majority of the population more likely to receive antidepressant medications was White compared to other races.

Furthermore, married patients represented the largest proportion of the study, followed by those who have never been married. Most of the patients belonged to middle- and high-income households and were privately or publicly insured.

The results reported that the patients using antidepressant medications showed some improvement in the MCS but not the PCS of the HRQoL. However, the difference in differences (D-I-D) analysis showed no difference between patients receiving the medication compared to the group that did not. The results were also unaffected by the demographical and socioeconomic variables that existed between the two groups.

Therefore, the current study determined that the continuous usage of antidepressant medications does not continue to improve patients’ HRQoL over time. Future studies should not only focus on the use of pharmacotherapy but also investigate the long-term impact of pharmacological and non-pharmacological interventions on the HRQoL of the patients.

Limitations

The study has certain limitations. First, the study uses retrospective data which prevents the ability to make a causal relationship. Second, it included all patients who had a documented diagnosis of depression regardless of the time of the first diagnosis. Third, a specific diagnosis of each type of depression cannot be carried out. Fourth, patients diagnosed with depression at the end of the first year or later were not included in the comparison between baseline and follow-up variables for HRQoL. Fifth, the codes used to identify depression were not only limited to depression. Finally, the MEPS data does not provide information on the severity of depression.

Written by

Suchandrima Bhowmik

Suchandrima has a Bachelor of Science (B.Sc.) degree in Microbiology and a Master of Science (M.Sc.) degree in Microbiology from the University of Calcutta, India. The study of health and diseases was always very important to her. In addition to Microbiology, she also gained extensive knowledge in Biochemistry, Immunology, Medical Microbiology, Metabolism, and Biotechnology as part of her master's degree.