The work impact of dysthymia in a primary care population

Abstract

Physicians regard individuals with dysthymia as having relatively normal levels of functioning. This study examines in detail the work impact of dysthymia in a population of employed primary care patients. As part of an observational study conducted between 2001 and 2003 in clinics associated with three health plans in Massachusetts, we compared 69 patients diagnosed with DSM-IV dysthymia without concurrent major depressive disorder to 175 depression-free controls. Patients were employed at least 15 h per week, had no immediate plans to leave the labor market, and no major comorbid medical conditions. We assessed work absences and productivity loss due to on-the-job performance limitations (“presenteeism”). Patients with dysthymia, compared with controls, had less stable work histories and a greater frequency of significant problems at work. While absence rates were not significantly different (1.2 vs. 0.74 days, P<.09), individuals with dysthymia experienced significantly greater on-the-job productivity loss (6.3% vs. 2.8%, P<.0001). Dysthymia is an unrecognized cause of work impairment that has long-term negative consequences for individuals and their employers. The persistence of dysthymia with its serious impact on work functioning calls out for the development of new interventions.

Introduction

A growing body of research now shows that, among working age adults, depression is a leading source of disability and diminished work productivity [1], [2], [3], [4], [5]. The recent National Comorbidity Survey [6] replication found that of the nearly 30+ million adults with lifetime prevalence of major depressive disorder (MDD) in the United States, 59% of individuals were severely impaired in their ability to perform social roles and, on average, were unable to work 35 days in the past year. Recently, researchers surveyed a representative household sample and, based on results, estimated that depression is responsible for an estimated $44 billion per year in medical costs ($12 billion) and lost productive work time ($32 billion), i.e., time unable to go to work and time at work unable to perform the job. This amount is three to four times greater than the losses attributed to adults without depression [7]. Figures such as these have fueled concerns about the cost and impact of depression on US workers and the economy. In an effort to help employers understand depression and develop appropriate responses, the American Psychiatric Association and several employer organizations have created a partnership (National Partnership of Workplace Mental Health), which will serve as an informational and collaborative resource for employers and clinicians [8].

In this study, we focus on the work impact of dysthymia. While functional and productivity losses associated with MDD have been described to date, little is known about the impact of dysthymia. Historically, it has been viewed as one of a number of subthreshold or characterologic conditions having fewer symptoms than MDD and assumed to have less functional impairment [9], [10]. Dysthymia is now considered a chronic ongoing mood disorder that is common, morbid, and treatable. In the clinical literature most individuals (50–75%) with dysthymia have recurrent episodes of MDD [9], [10], [11], [12], [13].

The psychosocial and clinical consequences are well-documented [11], [12], [14]. For example, research shows that, compared with controls, fewer individuals are married or employed. They also have a higher likelihood of having comorbid psychiatric diagnoses and problems with substance abuse. Despite these known consequences, studies indicate that individuals with dysthymia are frequently undertreated [15].

Few studies have assessed the work experiences of adults with dysthymia. What little evidence there is suggests that dysthymia results in a substantially impaired ability to perform activities at home and at work. The Epidemiological Catchment Area study found that 29% of patients with dysthymia obtained from a general medical sample had chronic restriction of their activity, including 16% who reported at least one bed day in the previous week and an average of 3 disability days per 90-day interval [16]. Stewart and colleagues [7] provide the most comprehensive review of the cost of lost productive work time for employees with dysthymia. Using the Primary Care Evaluation of Mental Disorders (PRIME-MD) as a classification tool [17], they estimated that 3.6% of US employees met the criteria for a diagnosis of dysthymia. Average lost productive work time (including absence hours and hours of productivity loss on the job) with dysthymia was 3.3 h per week compared to an expected 1.5 h for employees without depression or dysthymia.

Previous research on the work consequences of dysthymia has focused on population-based samples. In this study, we assess the impact of dysthymia on work and productivity in a sample of employed patients who were seen by physicians in primary care clinics. This is typically a less healthy population due to their healthcare utilization. Additionally, we use new productivity loss assessment metrics, which provide an in-depth assessment of work problems.