Prevalence of Burnout Syndrome in Patients Admitted with Acute Coronary Syndrome

Abstracts

Background:

Burnout Syndrome is the extreme emotional response to chronic occupational stress, manifesting as physical and mental exhaustion. Although associated with higher prevalence of cardiovascular risk factors, no study so far has evaluated whether the Burnout Syndrome could be a prevalent factor in non-elderly individuals active in the labor market, admitted for acute coronary syndrome (ACS).

Objective:

To evaluate the prevalence of the Burnout Syndrome in non-elderly, economically active patients, hospitalized with ACS.

Methods:

Cross-sectional study conducted in a tertiary and private cardiology center, with economically active patients aged <65 years, hospitalized with diagnosis of ACS. The Burnout Syndrome was evaluated with the Burnout Syndrome Inventory (BSI), which assesses workplace conditions and four dimensions that characterize the syndrome: emotional exhaustion (EE), emotional distancing (EmD), dehumanization (De) and professional fulfillment (PF). The Lipp’s Stress Symptoms Inventory for Adults (LSSI) was applied to evaluate global stress.

Results:

Of 830 patients evaluated with suspected ACS, 170 met the study criteria, 90% of which were men, overall average age was 52 years, and 40.5% had an average income above 11 minimum wages. The prevalence of the Burnout Syndrome was 4.1%. When we evaluated each dimension individually, we found high EE in 34.7%, high De in 52.4%, high EDi in 30.6%, and low PF in 5.9%. The overall prevalence of stress was 87.5%.

Conclusion:

We found a low prevalence of Burnout Syndrome in an economically active, non-elderly population among patients admitted for ACS in a tertiary and private hospital.

Acute Coronary Syndrome; Burnout, Professional; Inpatients: Stress, Psychological

Fundamento:

Síndrome de Burnout (SB) é a resposta emocional extrema ao estresse crônico ocupacional, manifestando-se como processo de esgotamento físico e psíquico. Embora associada com maior prevalência de fatores de risco, nenhum estudo avaliou até o momento se a SB poderia ser um fator prevalente em indivíduos não idosos, ativos no mercado de trabalho, admitidos por síndrome coronária aguda (SCA).

Objetivo:

Avaliar a prevalência da SB em pacientes economicamente ativos, não idosos, hospitalizados com diagnóstico de SCA.

Métodos:

Estudo transversal realizado em um centro de cardiologia terciário e privado, com pacientes economicamente ativos, com idade < 65 anos, hospitalizados com diagnóstico de SCA. Para avaliação da SB, aplicou-se o Inventário da Síndrome de Burnout (ISB), que avalia as condições do ambiente de trabalho e as dimensões que caracterizam a SB: exaustão emocional (EE), distanciamento emocional (DEm), desumanização (Des) e realização profissional (RP). Aplicou-se ainda o Inventário de Sintomas de Stress para Adultos de Lipp (ISSL) para avaliação de estresse global.

Resultados:

Dos 830 pacientes avaliados com suspeita de SCA, 170 preencheram os critérios do estudo, sendo 90% homens, com idade média de 52 anos, e rendimento médio acima de 11 salários mínimos em 40,5% da amostra. A prevalência da SB foi de 4,1%. Elevada EE esteve presente em 34,7%, elevado DEm em 52,4%, elevada Des em 30,6% e baixa RP em 5,9%. A prevalência de estresse geral foi de 87,5%.

Conclusão:

A SB foi pouco prevalente em pacientes ativos no mercado de trabalho, não idosos, e internados por SCA nesta amostra avaliada em um hospital cardiológico privado e terciário.

Síndrome Coronariana Aguda; Esgotamento Profissional; Pacientes Internados; Estresse Psicológico

Introduction

Stress is a complex psychophysiological reaction that characterizes the need of the organism to face a threat to its internal homeostasis¹. Although the response that characterizes the stress is acutely necessary against an aggressive stimulus, its chronicity is deleterious. In this situation, there is a continuous activation of the autonomic nervous system and neuroendocrine axis^2,3. Therefore, chronic stress is a recognized risk factor for coronary heart disease⁴, although situations of extreme acute stress are also associated with an increased incidence of cardiovascular events⁵.

In the last decades, several factors, such as demand for increased productivity, have generated greater occupational (i.e. work-related) stress. Like other forms of stress, occupational stress increases the chances of illness in the population, although a healthy lifestyle seems to mitigate this risk⁶. The Burnout Syndrome is the extreme emotional response to occupational chronic stress. The term "burnout, or "burn to exhaustion", indicates the collapse that arises after use of all available energy⁷, manifesting as a process of physical and mental exhaustion. The syndrome consists of multiple factors and is expressed in three dimensions: high levels of emotional exhaustion (EE) and depersonalization (composed by emotional distancing [EmD] and dehumanization [De]) and low professional fulfillment (PF). It depends directly on the conditions under which the work is performed and also in the interpersonal relationships involved in its execution^8,9. Its prevalence has been widely evaluated in several professional groups, in particular, health care workers such as doctors and nurses, in addition to workers in social fields, such as lawyers and teachers¹⁰.

Like other forms of stress, the Burnout Syndrome is associated with the presence of several cardiovascular risk factors^11,12. However, a possible association between the syndrome and triggering of cardiovascular events in economically active professionals has not yet been explored in the national literature. The aim of this study was to evaluate the prevalence of the Burnout Syndrome in individuals active in the labor market, admitted with acute coronary syndrome (ACS). The prevalence of global stress, not necessarily associated with work, was also evaluated.

Methods

Recruitment of Patients

We evaluated patients with complaint of chest pain admitted to an emergency service of a tertiary private hospital specialized in cardiology in the city of Curitiba (PR), and who were hospitalized for investigation or treatment of ACS. We included patients with confirmed diagnosis of ACS (angiographic evidence), aged ≥ 21 years and < 65 years, of both genders, and economically active in the labor market.

Recruitment was carried out in two phases. During the first phase, we conducted a pilot study with duration of 36 weeks in which 94 patients were included. For the second phase and continuation of data collection, the sample size was calculated based on the initial pilot study. Considering an initial estimated frequency of Burnout of 4%, with a maximum margin of error of 3.2% (95% confidence interval [95% CI]: 1.1% to 7.1%), a minimum of 164 patients would be required.

Data collection of both phases occurred from 5/17/10 to 3/1/12. The present study was approved by the Research Ethics Committee of the institution with assigned number 1940. All patients included in the study were informed about the goals of the study and signed an informed consent form (ICF).

Evaluation Protocol

The cardiological clinical evaluation followed a pre‑established protocol for care of patients with chest pain and suspected ACS¹³. The approach to invite the patient to participate in the study was individual and conducted by a psychologist in the patient's room, between the 3rd and 5th days of hospitalization. The application allocated 20 to 30 minutes for completion of the two instruments of psychological assessment of the Burnout Syndrome (BSI) and global stress (LSSI). For patients who preferred to fill out the questionnaires alone, this possibility was offered.

Psychological Instruments

Assessment of the Burnout Syndrome

For assessment of the Burnout Syndrome, we used the Burnout Syndrome Inventory (BSI) by Benevides-Pereira¹⁴. This inventory is composed of two parts and assessed in a Likert-type scale (0 to 4). Part I consists of 16 items related to the background of the work environment: the positive and the negative organizational conditions, with scores of 0 (never) to 4 (very often). Part II consists of 19 items that assess each dimension of the Burnout Syndrome individually (EE, EmD, De and low PF) with scores of 0 (never) and 1 (a few times per year) to 4 (every day). The reference values, between minimum and maximum averages, for the assignment of high, moderate or low levels were: Positive Organizational Conditions (POC, 22 – 26), Negative Organizational Conditions (NOC, 8 – 17), EE (4 – 9) and depersonalization, which is represented by the dimensions EmD (2 – 6) and De (4 – 7). The third dimension is the PF (10-15) which is inversely related to the above. According to this instrument, the dimensions are evaluated individually, also covering professions that are not assistive. As a diagnostic criterion for the Burnout Syndrome, this instrument follows the classic criterion of Maslach et al⁹ which requires the occurrence of high emotional exhaustion and depersonalization (De and/or EmD), concurrently with reduced PF at work.

Assessment of Stress

To evaluate the occurrence of stress, phase and prevalence of physical or psychological symptoms, we used the Lipp's Stress Symptoms Inventory for Adults (LSSI) validated in Brazil by and marketed by Editora Casa do Psicólogo¹⁵. This questionnaire consists of three parts assessing physical and psychological symptoms observed in the previous 24 hours (15 items), which define the Alert phase, during the previous week (15 items), which identifies the Resistance and Near-exhaustion phases, and during the previous month (23 items), which refers to the period of Exhaustion of the stress. Symptoms identified by the patient were marked in the questionnaire, and each item identified received one point.

Categorization of the Cohort Professions

Burnout Syndrome is linked to working activities. Much of the research has focused on the categories of assistive and health professionals, but in the 1990s it was observed that other professionals could also suffer from burnout⁹. Therefore, since the objective was to assess the prevalence of the Burnout Syndrome in economically active individuals, all occupational categories were included. For categorization, the professions were subdivided into three groups, according to the degree of bureaucracy involved or the need for interpersonal interaction involved: 1) assistive or health care, 2) administrative, and 3) operational. Although this division is arbitrary, it was based on the classification used in the international literature which defines as "white collar" those professionals with bureaucratic, managerial and empowerment of functions, and as "blue collar", those with less decision-making power, subordinates, as well as operational and manual laborers^16,17.

Statistical Analysis

We present in this study descriptive statistical analysis of the data we obtained. The results are expressed by frequencies and percentages (qualitative variables) or by averages and standard deviations (quantitative variables). The data were analyzed with the software IBM SPSS Statistics v. 20.

Results

a total of 830 patients with ACS were identified, 298 of whom were ≥ 65 years and 330 were not economically active, yielding 202 potentially eligible patients. Of these, 13 were discharged from the hospital before screening, two were unwilling to cooperate and 10 did not undergo coronary angiography. In total, 170 patients filled out the questionnaires (Figure 1) and 160 patients filled up the Stress Inventory.

Figure 1
Method of inclusion of the patients during the period of recruitment.

Characterization of the Cohort

The sample was composed predominantly by men (90.6%), and the average age of the overall cohort was 52.1 ± 7.2 years. With regard to schooling, 43.5% reported complete tertiary education. As for professional activity, 46.5% were employees in an administrative area, the average time in the profession was 20.0 ± 10.9 years and the average wage earning of 40.5% of the cohort was above 11 minimum wages. The weekly workload was greater than 40 hours per week in 54.7% of the patients (Table 1). The clinical history of the patients included in the study is described in Table 2. Regarding the cardiac diagnosis, 46.5% of the patients were identified with unstable angina, 26.5% with non-ST elevation myocardial infarction (NSTEMI) and 27.1% with ST-segment elevation myocardial infarction (STEMI). These patients had more extensive coronary heart disease, in addition to the event‑related artery: the average number of arteries with lesions (> 50%) per patient was 2.4 ± 1.3. Patients remained hospitalized for an average of 8.3 ± 4.2 days.

Table 1
Characterization of the cohort

Social Data		Mean	± SD	N
Idade		52.1	7.2	-
Race	White	-	-	134 (78.9%)
	Hybrid (Black/White)	-	-	30 (17.6%)
	Black	-	-	6 (3.5%)
Gender	Male	-	-	154 (90.6%)
Marital Status	Married	-	-	166 (97.7%)
Education	Incomplete elementary education	-	-	14 (8.3%)
	Complete elementary education	-	-	13 (7.6%)
	Incomplete secondary education	-	-	5 (3%)
	Complete secondary education	-	-	51 (30%)
	Incomplete tertiary education	-	-	13 (7.6%)
	Complete tertiary education	-	-	74 (43.5%)
Professional Category	Interpersonal/Health	-	-	44 (25.8%)
	Administrative	-	-	79 (46.5%)
	Operational	-	-	47 (27.7)
Time in the Occupation		20	10.9	-
Employment Status	Self-employed	-	-	59 (35%)
	Contract/Tenure track	-	-	58 (34%)
	Both			53 (31%)
Weekly Workload	Up to 40 hours per week	-		77 (45.3%)
	> 40 hours per week	-		93 (54.7%)
Monthly Income	Up to 5 MW			55 (32.5%)
	6 to 10 MW			46 (27%)
	> 11 MW	-	-	69 (40.5%)

• MW: Minimum wage.

Table 2
Clinical history

Health information		Mean	± SD	N
Hypertension		-	-	89 (52.4%)
Previous CAD		-	-	57 (33.5%)
Diabetes Mellitus		-	-	35 (20.6%)
Family History		-	-	83 (48.8%)
Dyslipidemia		-	-	75 (44.1%)
Stroke/TIA		-	-	3 (1.8%)
Depression		-	-	3 (1.8%)
Acute Coronary Syndrome	Unstable angina	-	-	79 (46.5%)
	NSTEMI	-	-	45 (26.5%)
	STEMI	-	-	46 (27.1%)
Number of Affected Arteries		2.4	1.3	-
Inpatient Days		8.3	4.2	-
Physical Activity	Sedentary			166 (97.6%)
	2 to 3 a week			4 (2.4%)
Smoking Status	Never smoked			81 (47.6%)
	Smoked until 6 months before			44 (25.9%)
	Previous smoker for > 6 m	-	-	45 (26.5%)
Alcoholism	Abstinence			39 (23%)
	Up to 30 g day			5 (2.9%)
	>30 g day			1 (0.6%)
	Weekends	-	-	125 (73.5%)

• CAD: coronary artery disease; TIA: transient ischemic attack; NSTEMI: non-ST elevation myocardial infarction; STEMI: ST-segment elevation myocardial infarction.

Levels of the Dimensions of the Burnout Syndrome

Considering as diagnostic criteria the presence of elevated EE and depersonalization (De and/or EmD), concurrently with reduced PF at work, the Burnout Syndrome was identified in 7 patients, yielding a prevalence of 4.1%. When we analyzed the dimensions individually, 34.7% of the sample had elevated EE, 52.4% had elevated EmD, 30.6% had elevated De, and 5.9% had low PF. Regarding background factors for the syndrome, there were high indices of negative work conditions in 52.9% of the participants, whereas positive work conditions were found in 34.1%.

Figure 2 quantifies the individual dimensions of the Burnout Syndrome.

Figure 2
Levels of individual dimensions of the Burnout Syndrome.

EE: Emotional Exhaustion; EmD: Emotional Distancing; De: Dehumanization; PF: Professional Fulfillment.

Stress Phases in Lipp's Quadriphasic Model

Of 160 responded LSSI questionnaires, 87.5% showed stress. The Alert phase was detected in 2.6%, the Resistance phase was present in 65.6%, Near Exhaustion occurred in 25.6% and Exhaustion in 6.2%. There was a prevalence of psychological symptoms in 51.3% of the subjects in the cohort, followed by physical symptoms in 39.4%, and a combination of both in 9.3% of the cases. According to Lipp¹⁸, the Quadriphasic Model of stress indicates that the phase of Resistance has two different moments characterized by increased symptoms. Thus, the beginning with a predominance of physical symptoms is regarded as the Resistance phase and the final stages, markedly psychological, are those of Near Exhaustion.

Figure 3 indicates the stages and symptoms of stress in the overall cohort.

Figure 3
Stages and types of stress symptoms.

Discussion

In this study, we observed that the Burnout Syndrome, an extreme form of occupational stress, was present in 4.1% of a non-elderly population still active in the job market, hospitalized with a confirmed diagnosis of ACS. This is the first national study correlating the Burnout Syndrome with major cardiovascular events. Global stress, not necessarily related to work, was diagnosed in 87.5% of the individuals in this cohort.

Cardiovascular diseases are the leading cause of death in Brazil and in the world, and ACSs account for a significant portion of these deaths¹⁹. The socioeconomic impact of ACS is larger when it reaches a younger and more productive segment of the population²⁰. Therefore, the recognition of all the factors that might be associated with its triggering is critical to reduce its damages. The role of chronic stress as a coronary risk factor is well known⁴. Since it is associated with continuous activation of the neuroendocrine-pituitary axis, not only it significantly increases the prevalence of risk factors, it also exposes to an increased risk of major cardiovascular events^2,11,21. Occupational stress is no different and also increases the incidence of coronary events^6,16,22,23. This form of stress is better explained by the Karasek model^16,24, or Demand-Control model, in which the power of decision involved in the performed activity is more important than the workload. The professional categories involved also interfere with the perception of the presence of occupational stress. Employees with administrative offices, known as "white collars", tend to have greater decision-making power when compared with operational employees, the so-called "blue collars". The low decision making and the high demand of work, which are prevalent in "blue collar" workers, have been described as instrumental to a higher elevation of diastolic blood pressure after stimulation with an α-agonist (phenylephrine), especially in black workers³. However, in a prospective study with follow-up of 18 years, the work category ("white" or "blue") was not determinant of an increased risk of myocardial infarction. In this same study, the only occupational characteristic associated with greater risk was the lack of future prospects at work¹⁶.

The progress of occupational stress to Burnout Syndrome is a continuous changing phenomenon of individual dimensions of the syndrome. We chose the BSI (Burnout Syndrome Inventory) as a diagnostic tool motivated by the process of standardization in the Brazilian population, but also because it contemplates all areas of professional activity. To verify the presence of the syndrome, four dimensions are considered, two of which (EmD and De) are the equivalent of depersonalization in the Maslach Burnout Inventory (MBI)^14,25. The BSI has been previously applied to a sample of Brazilian physicians and showed, as in our study, changes beyond the average in negative work conditions, EE and De²⁶. In this study, adverse work conditions also prevailed over positive ones, indicating that the participants notice more demands than resources in performing their professional activities. As for the dimensions of the syndrome, we observed that they use predominantly EmD as a way to counter the feeling of exhaustion. It draws attention in our cohort the high prevalence of PF. Considering that Burnout is understood as a form of defense - even if inadequate - against occupational stress, the data are consistent with the theoretical assumptions. More professionals were found in stress than in Burnout in our sample. A hypothesis for this is that the LSSI is unable to distinguish between types of stress, measuring instead the overall stress. On the other hand, Burnout arises when the worker, unable to find ways to cope with stressing stimuli arising in the work environment, remains in exhaustion which then follows a chronic course. Most of the participants were in the phase of Resistance according to the LSSI, which matches the theoretical condition of Burnout as coping and defense against the perceived stress. Patients may be resisting the stress through high dimensions of the Burnout Syndrome.

This study has a limitation in the extrapolation of its results (external validity). The patients were recruited from a single, tertiary, and private cardiology center. This justifies some findings, such as the high prevalence of individuals with higher education and earning above 11 minimum wages. An accurate estimation of the general prevalence of Burnout Syndrome in patients admitted with ACS would only be possible using a representative sample of the entire national population. Another limitation, determined by the cross-sectional design of the study, is the impossibility of assessing the Burnout Syndrome as a triggering factor of the ACS. We believe that even prospective studies have limitations in this regard, since in the long run, professionals are subject to changes in functions and even in jobs. However, we believe that by performing the first evaluation of the frequency of the Burnout Syndrome in patients with ACS, leaving the traditional model of evaluating its prevalence in an specific professional category, we are enabling a new area of investigation in which the Burnout Syndrome is no longer seen as just a labor problem, alerting to the possibility of its association with a greater impact on the overall health of the worker.

Conclusions

In conclusion, this study demonstrated that the Burnout Syndrome has a low prevalence in non-elderly, economically active patients who are admitted to the hospital with ACS. Future analyses involving populations with distinct economic realities from this cohort may expand the understanding of the association of occupational stress and cardiovascular diseases.

• Sources of Funding
  There were no external funding sources for this study.
• Study Association
  This article is part of the dissertation of master submitted by Ana Claudia Merchan Giaxa Prosdóscimo from Pontífica Universidade Católica do Paraná - PUC-PR.

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Publication Dates

• Publication in this collection
  16 Dec 2014
• Date of issue
  Mar 2015

History

• Received
  27 May 2014
• Reviewed
  23 Sept 2014
• Accepted
  13 Oct 2014