Background
During the last decade, burnout has become a public health issue affecting between 4% and 7% of the working population [
1]. Nevertheless, the diagnosis is not yet included in clinical classification systems such as the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) [
2] or the International Statistical Classification of Diseases and Related Health Problems (ICD-10) [
3]. To date, there is also no consensus on the definition of burnout and its core symptoms [
4‐
7], and the diagnosis overlaps tremendously in symptomatology with other diagnoses, especially chronic fatigue [
8] and depression [
9‐
11].
Despite some conceptual controversies [
4‐
7,
12], the most widely accepted definition of burnout is the one by Maslach, Schaufeli, and Leiter [
6], who defined it as a work-related stress syndrome characterized by three main symptoms: exhaustion, cynicism, and reduced professional efficacy. Exhaustion refers to feelings of depletion caused by various work demands; cynicism reflects a distant attitude towards work and the people one is working with; and reduced professional efficacy represents the negative self-evaluation that one is incompetent and no longer able to perform work tasks adequately. However, past research has shown that burnout manifests in different ways. A varying number of burnout profiles [
13‐
15] has been observed across studies, and multifaceted longitudinal trajectories of the burnout symptoms [
16‐
21] indicate different pathways into burnout. Different burnout subtypes might therefore exist.
The person-oriented approach to burnout [
15,
22] is one possibility to investigate burnout subtypes. It identifies different groups in a population that are intraindividually homogenous, but interindividually heterogeneous in various aspects such as symptomatology, psychopathology, and job- and person-related factors. In past research, the person-oriented approach has been used to identify typical burnout profiles [
15], which might represent people at different developmental stages in the burnout cycle or truly different burnout subtypes [
13,
23‐
27].
The most frequent burnout profiles that emerged in these studies [
13‐
15], predominantly from the analysis of the three dimensions of the Maslach Burnout Inventory (MBI) [
28], were the
burned-out profile and the
healthy or engaged profile representing people with severe or low symptomatology in all three burnout dimensions. Another common symptom profile was the
exhausted/cynical profile characterized by high exhaustion and cynicism, but simultaneously high professional efficacy. Typical incongruent scoring patterns included the
exhausted or overextended, the
cynical or disengaged, and the
reduced professional efficacy profile representing people with rather mild symptomatology where only one symptom is pronounced. However, one has to keep in mind that most previous studies have been conducted in non-clinical samples, which consist of people who report symptoms of a burnout but have not been diagnosed by a psychiatrist or clinical psychologist and who are all still working [
13‐
15]. Therefore, the so-called healthy worker effect [
29] occurred in these studies, and not all of the prior discussed burnout profiles might genuinely represent clinical burnout subtypes who need or seek treatment in specialized psychosomatic clinics or rehabilitation programs.
To date, only one study [
30] has investigated subtypes based on burnout profiles in working-aged adults whose working ability was reduced or threatened by disease, disability or some other disorders, and who were therefore enrolled in an employee rehabilitation program. This study has identified four of the above mentioned subtypes: two subtypes with severe symptoms, namely the
burned-out profile and the
exhausted/cynical profile, one subtype with milder symptoms, namely the
reduced professional efficacy profile, and the
healthy profile. However, some of these profiles might have occurred because Hätinen et al. [
30] explored a heterogeneous patient sample suffering from various physical, psychological, and social limitations, symptoms, and disabilities.
For that reason, the present study aims to examine whether meaningful burnout subtypes may be found in a more homogeneous group of clinically diagnosed burnout patients treated in a specialized psychosomatic clinic if the three main burnout symptoms suggested by Maslach, Schaufeli and Leiter [
6] are considered and explored within a person-oriented approach [
15]. Additionally, we will investigate the relationship of these subtypes to depression since an intense discussion has been going on during the last years [
9‐
12,
31‐
54] whether burnout can be seen as a distinct construct or rather a new label of an already known state.
A growing body of literature has examined the overlap between burnout (subtypes) and depression-level, both in the working population [
9,
12,
23,
31,
32,
39‐
48,
50‐
52] and in clinical patients [
30,
54], but findings are heterogeneous and inconsistent. Several studies in the working population reported strong correlations between burnout and depression [
9‐
11,
31,
32], especially between exhaustion and depression [
10,
31,
32], while in clinically diagnosed burnout patients, the strong exhaustion-depression overlap could not be replicated [
55]. Low to moderate correlations between burnout and depression were also found by others in the working population [
40,
41,
47], whereas Ahola et al. [
45] reported that burnout and depression overlapped particularly in severe burnout. These heterogeneous findings may partly result from using different measures of burnout and depression [
11,
37] with some measures reflecting a larger concept redundancy between both disorders (for a discussion on this topic, see Maslach & Leiter [
37]). Furthermore, longitudinal studies have been used to study the complex relationship between burnout and depression, but yielded inconsistent results as well. Some authors reported reciprocal relations between burnout and depression [
42‐
44], while others found a unidirectional relationship from burnout to depression [
46‐
50] or vice versa [
51‐
53] or no predictive relation [
36]. Studies applying a person-oriented approach to explore the burnout-depression overlap [
9,
31] detected that burnout and depression were not separable from each other. Moreover, both disorders developed longitudinally in tandem supporting the hypothesis that burnout and depression may be the same disorder. In clinical burnout patients, longitudinal studies are still sparse [
55]. Besides, only a few studies have explored the burnout-depression overlap by applying a person-oriented approach in clinical burnout patients [
54] or burnout rehabilitation clients [
30,
56], respectively. Yet, the overlap between burnout symptoms and depression might differ between burnout subtypes. Boersma and Lindblom [
23] found in the working population that subtypes experiencing high exhaustion were more depressed than other burnout subtypes, and van Dam [
54] could distinguish a group with mild symptoms from a group with severe symptoms on several measures (burnout, depression, anxiety, and fatigue) in clinically diagnosed burnout patients. In contrast, Hätinen et al. [
30] found in working-aged rehabilitation clients that all subtypes were equally depressed, but in this study, a mixed patient sample suffering from various physiological, psychological, and social limitations, symptoms, and disabilities was explored.
Inconsistencies in organizational risk factors have been found in burnout subtypes as well. According to the job demands-resources (JD-R) model [
57], burnout develops when job demands (e.g., workload, time pressure, conflict) are high, while resources (e.g., autonomy, social support, positive relationship with supervisor) are limited. Resources are therefore no longer able to buffer the negative impact of high demands on stress reactions [
58]. Job demands and resources have also been linked to specific burnout symptoms: exhaustion is caused by high workload and emotional demands, whereas cynicism, reduced professional efficacy, and disengagement have been associated with a lack of resources [
59‐
61]. Previous studies on burnout subtypes in the working population [
13,
23,
27] likewise found that workload was high in subtypes experiencing high exhaustion (
burned-out,
exhausted/cynical, and
exhausted), but resources were only low in subtypes with severe burnout symptoms (
burned-out and
exhausted/cynical), particularly in the
burned-out subtype [
13]. Yet, in clinical rehabilitation patients, Hätinen et al. [
30] did not find any differences in job stressors and resources between three different burnout subtypes (
burned-out,
exhausted/cynical, and
low professional efficacy), although recovery was associated with a decrease in job demands and an increase in job resources [
56].
Because most prior research was conducted within the scope of the JD-R model of burnout, recovery has received comparatively less attention in relevant research. The recovery/resources-stress-balance model [
62‐
64] is similar to the JD-R model but focusses additionally on recovery as crucial aspect to prevent burnout. According to the model, burnout develops after prolonged periods of stress without sufficient recovery and resources. More precisely, the homeostatic balance between stress and recovery is impaired because resources that were depleted during phases of stress are not adequately restored in the recovery phase [
63]. The role of recovery has, however, not been systematically explored in burnout subtypes, particularly not in clinical burnout patients enrolled in an employee rehabilitation program.
Therefore, the current study aims to explore different burnout subtypes in clinical burnout patients, who are enrolled in an employee rehabilitation program in a psychosomatic clinic, by performing cluster analysis with the three subscales of the Maslach Burnout Inventory – General Survey (MBI-GS) [
28] as clustering variables. Furthermore, depression levels will be compared among the subtypes, based on the expectation that the strength of the obviously existing overlap between burnout symptoms and depression might differ between burnout subtypes. Finally, differences between the burnout subtypes in the recovery/resources-stress balance and sociodemographic characteristics will be explored.