The American Journal of Managed Care August 2014
The Effect of Depression Treatment on Work Productivity
Depression is associated with lowered work functioning, including absence, productivity impairment at work, and decreased job retention. Although high-quality depression treatment provided in clinical trials has been found to reduce symptoms and improve work function, the effectiveness of routine treatment for depression in primary care has received less attention.
This prospective cohort study investigated the relationship between improvements in both depression symptoms and productivity in outpatients from 77 clinics in Minnesota following routine depression treatment.
Data were obtained from patients receiving usual care for depression prior to initiation of a statewide quality improvement collaborative called DIAMOND (Depression Improvement Across Minnesota: Offering a New Direction). Patients started on antidepressants were surveyed on depression symptom severity (Patient Health Questionnaire [PHQ-9]), productivity loss (Work Productivity and Activity Impairment questionnaire [WPAI]), health status, and demographics. Data were collected again 6 months later to assess changes in depression symptoms and productivity.
Data from 432 employed patients with complete baseline and outcome data showed significant reductions in depression symptoms and increases in productivity (P < .0001) over 6 months. Greater improvements in productivity at 6 months were associated with greater improvement in depression symptoms as well as with greater depression severity (P < .0001) and poorer productivity (P < .0001) at baseline.
This study demonstrated a significant relationship betweenimprovement in depression symptoms and improvements in productivity following routine primary care depression treatment. These findings underscore the benefit of depression care to improve work outcomes and to yield a potential return on healthcare investment to employers.
Am J Manag Care. 2014;20(8):e294-e301
Routine treatment of depression in primary care settings is effective in significantly reducing depression symptoms and improving productivity at work.
Although high-quality depression treatment provided in clinical trials has been found to reduce symptoms and improve work function, the effectiveness of routine treatment for depression in primary care has received less attention.
Patients with more significant baseline depression symptoms and productivity loss improved the most on these measures 6 months after treatment.
Productivity improvements at 6 months were greatest for patients showing response or remission following depression treatment.
- Employers may realize a positive return on investment for depression care based on productivity gains following depression treatment
Depression is prevalent and is associated with such indirect costs as increased work absence, impaired productivity while at work, and decreased job retention across a wide variety of occupations.1-4 In addition, several studies have shown that even minor or subthreshold depression (including dysthymia) is related to lowered work performance.5-7
Fortunately, high-quality depression treatment has been found to reduce symptoms, to improve work function, and to be cost-effective.8-14 Much of this evidence comes from clinical trials or cross-sectional studies of the effectiveness of antidepressants15,16 or depression-care management interventions.17 Aikens et al18 analyzed trajectories of improvement in depressive symptoms and work function (among other patient-reported outcomes) following antidepressant treatment and found that work performance improves in proportion to depression symptom remission. Results from the study by Woo et al of Korean employees diagnosed with major depressive disorder showed that their depressive symptoms and lost productive time decreased significantly after 8 weeks of antidepressant treatment.19 Randomized trials of non-pharmacologic enhanced depression-care management also demonstrated improved symptom and work function following the interventions.8,10
Despite the encouraging findings of work function improving with depression symptom remission, less is known about this relationship in primary care settings that are not involved in clinical trials, though recently published work does suggest that collaborative care for depression is associated with symptom remission and improvement in work function.20 The goal of the present study was to investigate the relationship between changes in depression symptom severity and changes in productivity loss following routine outpatient depression treatment provided to a large sample of patients receiving care at 77 clinics in Minnesota.
Data were obtained from patients participating in the DIAMOND (Depression Improvement Across Minnesota, Offering a New Direction) Study, an evaluation of a statewide depression quality improvement initiative in Minnesota that included 88 clinics from 23 medical groups. Details on the study design and methods have been published elsewhere.21 The results presented here represent baseline and 6-month outcome data for patients who received usual care for depression at 77 of the these clinics prior to implementation of the DIAMOND program.
Patient Recruitment and Enrollment
All patients with health plan claims data showing them to be newly started on antidepressant medications at one of the participating clinics were identified on a weekly basis by the health plans and sent a letter about the study, providing a 1-week opportunity to opt out before being called by the research survey center to determine eligibility for participation and to complete a baseline survey by phone. Patients were eligible if they were 18 years or older, had filled a new antidepressant prescription (and none in the prior 4 months) from a primary care clinician at one of the participating clinics for the treatment of depression, and had a depression symptom severity score of 7 or greater on the Patient Health Questionnaire 9-item screen (PHQ-9).22 Employment was not an eligibility criterion for patient participation in the larger DIAMOND Study, so for the purpose of this analysis, we included only the subset of patients employed for wages at least part-time at baseline and 6 months, and who had baseline and 6-month data on both the PHQ-9 and the Work Productivity and Activity Impairment Questionnaire (WPAI),2 the measure used to assess productivity loss. Data from the baseline and 6-month surveys were analyzed to assess changes in depression symptoms and productivity loss following treatment. The study protocol was reviewed, approved, and monitored by the HealthPartners Institutional Review Board.
Patient self-report surveys were used to provide information on depression severity, work absence, productivity impairment, and health status (a single item asking patients to rate their overall health), as well as demographic characteristics including employment status. The PHQ-9, widely accepted as a valid measure of depression severity, was used to measure the severity of depression symptoms.22,24-26 The PHQ-9 yields a continuous score from 0-27 with cut points representing mild (5), moderate (10), moderately severe (15), and severe (20) depression, respectively.