Definition of burnout
Narratives of burnout, particularly among doctors, can be traced back centuries, and the phenomenon has traditionally been regarded as an inherent occupational hazard, described as early as the 9th century in Adab al-Tabib, an Arabic textbook on medical ethics (5).
The term 'burnout', as it is understood today, was first introduced in 1974 by the American psychologist Herbert Freudenberger (1926–99) (6). He defined it as a state of physical and mental exhaustion arising from workplace stress. Freudenberger described the risk of burnout among healthcare personnel in his own clinic and highlighted preventive measures that staff should focus on to reduce this risk.
The American psychologist Christina Maslach and her colleagues have been leading figures in research in this field since the 1970s (7). To measure burnout, they developed the Maslach Burnout Inventory (MBI), and although specialists in other fields have developed similar instruments, the MBI is regarded as the reference standard (8). The instrument defines burnout as 'a syndrome of emotional exhaustion and cynicism that occurs frequently among individuals who do "people work" of some kind' (9). In the MBI, this is operationalised through three dimensions: emotional exhaustion, mental distancing (depersonalisation/cynicism) and reduced personal accomplishment (also called reduced professional efficacy).
There are several definitions of burnout, and the lack of standardisation was discussed in 2021 by the Network on the Coordination and Harmonisation of European Occupational Cohorts (OMEGA-NET) (10). The expert panel, comprising representatives from 29 countries, agreed on a revised definition of burnout: 'In a worker, occupational burnout or occupational physical AND emotional exhaustion state is an exhaustion due to prolonged exposure to work-related problems.'
No further explanation is given of the term 'prolonged exposure', but in other medical contexts a period exceeding three months is generally assumed. Defining burnout solely in terms of emotional exhaustion, without including the other two dimensions, meant that the panel did not draw on a theory of how burnout develops. Instead, they adopted a pragmatic approach, seeking a common denominator across existing definitions. Mental distancing is primarily understood in several of the definitions as a coping strategy for managing exhaustion, while reduced personal accomplishment is considered a consequence of exhaustion (11).
Exhaustion is a symptom of a wide range of conditions and is therefore not specific to burnout (8). In both clinical practice and research, distinguishing symptoms of burnout from depression or depressive symptoms is challenging. There is also no correlation between how burnout is defined and how it is measured. The development of burnout and the symptoms that should be included as diagnostic criteria remain a matter of debate. A distinction is also made between burnout as an individual problem, where treatment may include cognitive behavioural therapy or medication, and burnout from an organisational perspective, where interventions are aimed at the workplace.
In both clinical practice and research, distinguishing symptoms of burnout from depression or depressive symptoms is challenging
In the International Classification of Primary Care (ICPC), which is used in general practice, burnout is classified as a symptom rather than a diagnosis (P29) (12). Meanwhile, ICD-11 classifies burnout as an occupational phenomenon under the chapter 'Factors influencing health status or contact with health services' (13), and defines it as follows: 'Burnout is a syndrome conceptualised as resulting from chronic workplace stress that has not been successfully managed. It is characterised by three dimensions: 1) feelings of energy depletion or exhaustion; 2) increased mental distance from one's job, or feelings of negativism or cynicism related to one's job; and 3) a sense of ineffectiveness and lack of accomplishment. Burnout refers specifically to phenomena in the occupational context and should not be applied to describe experiences in other areas of life'.
The ICD-11 definition is more consistent with Maslach's conceptualisation than with the expert consensus from 2021. Its focus is on chronic workplace stress and distinguishes burnout from other conditions characterised by exhaustion, such as chronic fatigue syndrome (CFS)/myalgic encephalomyelitis (ME). We therefore anticipate that the ICD definition will eventually become the most widely used operational definition of burnout, despite the extensive work carried out by the expert panel in 2021. However, it raises questions for many clinicians working with burnout. Experience from clinical practice suggests that burnout can rarely be understood solely in terms of workplace factors; it tends to reflect an interplay between stressors both within and outside the workplace – a form of cumulative life stress – that contributes to the development of chronic stress.
Experience from clinical practice suggests that burnout can rarely be understood solely in terms of workplace factors; it tends to reflect an interplay between stressors both within and outside the workplace
The field is further complicated by the fact that the American Psychiatric Association adopts a different approach in its classification system, DSM-5 (14). In DSM-5, burnout is subsumed within the category 'Trauma- and Stressor-Related Disorders', which also includes adjustment disorders and post-traumatic stress disorder (PTSD).
Since 2005, the Swedish version of ICD-10 has included burnout as a separate diagnosis: exhaustion disorder (15), and the prevalence of this has increased considerably in Sweden (16). The diagnosis is not limited to workplace stress and is likely to encompass a range of different conditions. Critics have therefore argued that there is still insufficient scientific evidence to regard the Swedish diagnosis as a distinct clinical entity and that its diagnostic criteria are too broad to be clinically useful.
The absence of a model for the pathophysiological processes underlying disease development, together with the variability in diagnostic criteria, makes it difficult to argue that burnout constitutes a distinct disease entity. Nevertheless, there is little doubt that burnout represents a real and burdensome condition. The disagreement is largely academic and relates to how burnout is conceptualised within the biopsychosocial model of illness (7). Progress will require a common classification framework, but no consensus has yet been achieved within the field. Consequently, official health statistics do not capture the prevalence of burnout, and current knowledge is based largely on research studies with differing inclusion criteria, study populations and observation periods.