Enriched environment at work: Disassociated from stress and burnout

Abstract

BACKGROUND:

Enriched environment at work (EEW), in terms of high mental demands at work, may be of great relevance for preventative efforts against cognitive decline and dementia as previous studies have shown. Yet, there is the concern that high EEW mental demands may accelerate stress and cause burnout.

OBJECTIVE:

The aim of our study was to investigate how EEW mental demands are related to stress and burnout.

METHOD:

A convenience sample of employees in the city area of Leipzig, Germany, was asked to fill out the Copenhagen Burnout Inventory and indicate for each EEW mental demand the level experienced, demandingness, and stressfulness.

RESULTS:

Multivariate linear regression and structural equation modelling suggested that only some EEW mental demands were perceived as stressful when the level of the respective EEW mental demand was high. Higher stressfulness was associated with burnout symptoms – however, high levels of EEW mental demands were not significantly associated with burnout (neither directly nor indirectly).

CONCLUSIONS:

Our findings implied that subjectively perceived stressfulness seems to be a more relevant aspect than the actual level of the demand itself. However, further studies are necessary to validate our findings.

Keywords

Mental demands cognitive demands occupational health job strain work environment

1 Introduction

The enriched environment at work (EEW) describes a work environment that is enriched with certain mental demands, which have been shown to protect against cognitive decline in old age and against dementia in previous studies [1, 2]. These EEW mental demands encompass, for example, interpreting information and planning activities. The original concept of enriched environment was developed in the context of animal studies. Results of various animal studies have demonstrated that enriched environments seem to protect against neurodegenerative diseases, such as dementia, by upregulating neurogenesis and synaptic plasticity [3]. First human studies that adopted the concept of enriched environment suggest that these protective effects could also apply to the human work environment: High levels of mental demands at work, in particular those stimulating executive cognitive functioning and verbal abilities, may preserve cognitive functioning for a longer lifetime period [2] and decrease the risk of dementia [1]. Considering that the aging of societies leads to a greater proportion of elderly individuals in the work force and a larger number of individuals affected by age-related cognitive decline and dementia, enriched environment at work (EEW) may be of great relevance for preventative efforts. Yet, there is the concern that high mental demands at work such as those found in EEW may accelerate stress and could cause burnout [4, 5].

1.1 Demands and stress

Research on stress in the work environment emphasizes that too high demands at work may lead to a stress reaction. Demands at work, which are commonly considered to be stressors, are work overload, too much time pressure, or insufficient resources [6, 7]. Experiencing these types of stressors at work could trigger a physical stress reaction, which, if experienced chronically is associated with a greater risk for lower productivity, long-term sick leave [8], ineffectiveness at the job, or burnout [7]. However, whether demands at work trigger a stress reaction also depends on the appraisal of the situation or the context in which the demand occurs [9]. For example, situations that involve public speaking or social evaluation elicit an exceptionally strong stress response [10]. Hence, the effect of demands at work on a stress reaction may not only depend on the type of demand but also on the situation in which it occurs. Previous research on high demands at work and stress focused on the quantity of work load, time pressure, or resources. Several studies have shown that such work conditions with high physical and emotional demands (as, for example, measured in the Karasek job-demand model) are associated with a higher risk of exhaustion, physical illness, and absenteeism (e.g., [11, 12]). It remains unclear whether mental demands at work – in particular those that describe EEW – are eventually causing similar stress reactions.

The aim of the present study was therefore to investigate whether high levels in these particular EEW mental demands are associated with stress. We hypothesize that high EEW mental demands may not in every case be associated with a high stress level: As a review by A.W.K. Gaillard) has summarized, studies have shown that a stress reaction depends on the cognitive appraisal, expectations, processing capacity, the probability of errors, task configuration, and emotional arousal upon the demands present [13]. Accordingly, we aimed to verify the hypothesis that higher levels in EEW mental demands at work are associated with a higher subjectively perceived stress (Hypothesis 1).

1.2 Demands and burnout

A long-term consequence of chronic stress at work can be burnout. Burnout is described as “a state of physical, emotional, and mental exhaustion that results from long-term involvement in work situations that are emotionally demanding” [14]. Moreover, as Maslach [15] puts forward, burnout seems to be a response that results from a misfit between the worker and the job. Indeed, research findings emphasize strong associations between employee-work requirements-misfits (such as excessive emotional demands or role ambiguity) and burnout, but point out also strong associations between work conditions (such as difficulties with job task identity, task significance, autonomy, lack of feedback, or lack of sufficient information) and burnout symptoms [16]. Hence, burnout seems to be a result of a lack of resources to fulfill the work requirements, either from the individual worker (i.e. abilities) or the work conditions [6].

Suffering from burnout also comes with adverse long-term consequences: Studies observed higher turnover rates, higher absenteeism, decreased job effectiveness [7], and even increased risks for coronary heart disease [17], depression [18], and type 2 diabetes [19]. Therefore, it is important to explore whether high mental demands within an enriched environment at work may be associated with burnout symptoms. Based on the fact that burnout symptoms seem to depend not only on demands but also on available resources including motivational processes, organizational and contextual factors [20], we assume that high EEW mental demands alone are not generally causing burnout symptoms. Nonetheless, we aim at verifying the hypothesis that higher levels in EEW mental demands are not associated with a higher burnout levels (Hypothesis 2).

In order to investigate in more detail whether and how high EEW mental demands may increase stress and cause burnout, we examined the factor structure of the EEW mental demands. In a first step, we identified the factor structure of the levels reported for each EEW mental demand. Then we compared whether this factor structure corresponded to the factor structure of the reported demands and reported stress for respective EEW mental demands. In a second step, we tested our two hypotheses by using these factors. Specifically, we examined whether some factors showed strong associations between the level of mental demands and the levels of stress and burnout, and whether some factors did not show these associations.

2 Methods

2.1 Study population

A cross-sectional study was conducted investigating a convenience sample of employees. A total of 150 paper-and-pencil questionnaires were distributed randomly within the university campus area and through personal contacts within the city of Leipzig, Germany, and the surrounding 200 km. The questionnaires were accompanied by a letter explaining the purpose of the study. The participation was completely voluntary. Informed consent was provided on a separate sheet, so that the questionnaires did not contain any personal information except age, gender, and occupational indicators. Thus, confidentiality and anonymity was guaranteed. A total of 62 questionnaires were returned (response rate 41.3%). As 16 questionnaires could not be used for the intended analyses due to missing data, 46 questionnaires were included in the analyses. Sample size calculation based on the Yamane formula for continuous outcomes indicated that, with the given standard deviations (see Table 3) and a margin of error of 0.03, the optimal sample size is 31. Individuals whose questionnaires were excluded from the analyses were more likely to be female (x² = 4.723, df = 1, p = 0.030) and were younger (U = 242.000, p = 0.042). There were no significant differences between included and excluded questionnaires concerning level of school education (x² = 4.300, df = 2, p = 0.116), weekly work hours (U = 217.000, p = 0.123), overall level of demands (U = 298.000, p = 0.237) or stress (U = 345.000, p = 1.000), burnout (personal burnout: U = 323.000, p = 0.986; work burnout: U = 394.000, p = 0.205), or whether they perceive their job as manageable (x² = 1.396, df = 1, p = 0.237).

Study participants, whose questionnaires were included in the analyses were on average 40.3 (SD 10.3) years old, had all completed high school, had worked in their job on average for 13.0 (SD15.5) years, and worked a mean of 37.6 (SD 13.1) hours per week. Of the participants, 56.5% (N = 26) were male and 43.5% (N = 20) were female. A total of 71.2% (N = 32) participants were salaried employees. Of all the participants, 40.0% (N = 18) were employees with independent responsibilities, 15.6% (N = 7) were executive staff, 13.3% (N = 6) were skilled workers, and the remaining 31.1% (N = 15) could not be classified into one occupational group (i.e., clerks, freelancer, independent business, civil service, senior officials). The majority of the study participants earned between 1,000\euro and 2,700\euro per month; 15.9% (N = 7) earned less than 1000\euro per month and 25% (N = 11) more than 2700\euro per month.

2.2 Standard protocol approval and patient consents

The study participants provided informed consent prior to study participation. The study was approved by the ethics committee of the University of Leipzig on March 23, 2015 (approval number: Az 369-14-17112014).

2.3 Enriched environment at work (EEW): Mental demands

The assessment of mental demands at work was based on the definition of EEW developed by Then et al. [1]. Our study included only those EEW mental demands that have shown to be significant protectors against cognitive decline and dementia in previous studies [1, 2]: The mental demands of the ‘verbal’-index and the ‘executive’-index. A detailed description of the EEW mental demands can be found in the appendix (Table A.1). In order to obtain more precise results, we made two small modifications in the present study. First, we split the variable ‘4.A.4.a.7 Resolving Conflicts and Negotiating with Others’ into ‘resolving conflicts’ and ‘negotiating’. Second, we divided the variable ‘4.A.2.a.3 Evaluating Information’ into ‘interpreting’ and ‘analysing’ information. Participants were asked to indicate for each EEW mental demand, their experienced level, demandingness, stressfulness, and frequency on a scale from 1– 5 (low to high). If a participant indicated a frequency of ‘never’ for an EEW mental demand but did not provide information on level, demands, or stressfulness, we imputed the means of other participants who also indicated ‘never’ for this particular EEW mental demand.

Table 1
Mean scores in the frequency, level, demandingness, and stressfulness of those mental demands at work that describe an Enriched Environment at Work (EEW)

EEW mental demand Frequency (M, SD) Level (M, SD) Demandingness (M, SD) Stressfulness (M, SD)

Providing Consultation and Advice 4.50 (0.94) 3.09 (1.21) 3.70 (0.81) 2.17 (0.77)

Scheduling Work and Activities 4.67 (0.73) 2.67 (1.06) 3.59 (0.72) 2.70 (0.84)

Resolving Conflicts 3.78 (1.17) 2.83 (1.06) 3.59 (1.00) 3.33 (0.92)

Negotiating with Others 3.07 (1.45) 2.83 (1.29) 3.43 (1.05) 2.89 (0.97)

Coordinating Work and Activities 3.61 (1.51) 2.83 (1.20) 3.20 (1.07) 2.43 (0.86)

Guiding, Directing, and Motivating Subordinates 3.76 (1.46) 2.87 (1.09) 3.30 (0.96) 2.54 (0.96)

Getting Information 4.67 (0.63) 3.04 (1.10) 3.24 (0.79) 2.22 (0.96)

Evaluating Information 4.13 (1.05) 2.87 (0.98) 3.59 (0.93) 2.37 (0.93)

Interpreting the Meaning of Information 4.74 (0.68) 3.59 (1.17) 3.61 (0.83) 2.35 (0.92)

Updating and Using Relevant Knowledge 4.57 (0.66) 3.50 (0.98) 3.74 (0.91) 2.33 (0.79)

Developing Objectives and Strategies 3.87 (0.89) 2.67 (1.01) 3.93 (0.83) 2.98 (0.77)

Analysing Information 4.43 (0.78) 3.02 (0.93) 3.54 (0.81) 2.48 (0.94)

EEW mental demand	Frequency (M, SD)	Level (M, SD)	Demandingness (M, SD)	Stressfulness (M, SD)
Providing Consultation and Advice	4.50 (0.94)	3.09 (1.21)	3.70 (0.81)	2.17 (0.77)
Scheduling Work and Activities	4.67 (0.73)	2.67 (1.06)	3.59 (0.72)	2.70 (0.84)
Resolving Conflicts	3.78 (1.17)	2.83 (1.06)	3.59 (1.00)	3.33 (0.92)
Negotiating with Others	3.07 (1.45)	2.83 (1.29)	3.43 (1.05)	2.89 (0.97)
Coordinating Work and Activities	3.61 (1.51)	2.83 (1.20)	3.20 (1.07)	2.43 (0.86)
Guiding, Directing, and Motivating Subordinates	3.76 (1.46)	2.87 (1.09)	3.30 (0.96)	2.54 (0.96)
Getting Information	4.67 (0.63)	3.04 (1.10)	3.24 (0.79)	2.22 (0.96)
Evaluating Information	4.13 (1.05)	2.87 (0.98)	3.59 (0.93)	2.37 (0.93)
Interpreting the Meaning of Information	4.74 (0.68)	3.59 (1.17)	3.61 (0.83)	2.35 (0.92)
Updating and Using Relevant Knowledge	4.57 (0.66)	3.50 (0.98)	3.74 (0.91)	2.33 (0.79)
Developing Objectives and Strategies	3.87 (0.89)	2.67 (1.01)	3.93 (0.83)	2.98 (0.77)
Analysing Information	4.43 (0.78)	3.02 (0.93)	3.54 (0.81)	2.48 (0.94)

Notes: M – mean; SD – standard deviation; Frequency – range: 1 (never) to 5 (evey day); Level – range: 1 (low) to 5 (very high); Demandingness – range: 1 (not at all) to 5 (very demanding); Stressfulness – range: 1 (not at all) to 5 (very much).

2.4 Burnout

Burnout was assessed with the Copenhagen Burnout Inventory [21], which comprises two scales: The work-related burnout and the personal burnout. Personal burnout describes a general condition of physical and psychological exhaustion; whereas, work-related burnout describes exhaustion related to work only [21]. Both scales are scored from 0 (never) to 100 (always).

Almost all participants (91.3% ; N = 42) reported that they can perform their job adequately. Yet, 52.2% (N = 24) reported an immense increase in work demands the past years, the remaining participants reported some increase. On a scale from 1 (very low) to 10 (very high), participants rated their job’s overall demandingness as 8.15 (SD 1.32) and overall stress experienced as 6.55 (SD 1.83). Only 19.6% (N = 9) of the participants perceived demanding work tasks to be also stressful. The mean burnout scores were 44.02 (SD 17.07) for personal burnout and 31.02 (SD 13.39) for work burnout respectively.

Table 2
Rotated factor loadings of the perceived level, demandingness, and stressfulness of those mental demands at work that describe an Enriched Environment at Work (EEW)

EEW mental demand Demandingness Level Stressfulness EEW Category assigned

Factor 1 Factor 2 Factor 3 Factor 1 Factor 2 Factor 3 Factor 1 Factor 2

Providing Consultation and Advice 0.434 0.396 0.455 0.448 0.357 0.357 0.495 0.412 1

Scheduling Work and Activities 0.120 0.326 0.789 0.524 0.222 0.377 0.432 0.452 1

Resolving Conflicts 0.262 0.645 0.433 0.621 0.138 0.462 0.146 0.334 2

Negotiating with Others – 0.005 0.440 0.165 0.719 0.102 0.196 0.088 0.214 2

Coordinating Work and Activities 0.348 0.814 0.130 0.714 0.314 0.075 0.043 0.763 2

Guiding, Directing, and Motivating Subordinates 0.155 0.910 0.207 0.672 0.182 0.101 – 0.078 0.644 2

Getting Information 0.889 0.228 – 0.071 0.234 0.726 0.310 0.620 0.131 3

Evaluating Information 0.705 – 0.115 0.257 0.005 0.582 0.501 0.888 0.033 3

Interpreting the Meaning of Information 0.741 0.225 0.199 0.333 0.759 – 0.088 0.882 0.111 3

Updating and Using Relevant Knowledge 0.702 0.217 0.184 0.213 0.725 0.294 0.773 0.114 3

Developing Objectives and Strategies 0.458 0.264 0.409 0.292 0.170 0.803 0.347 0.408 4

Analysing Information 0.400 0.340 0.398 0.377 0.402 0.432 0.649 0.355 4

EEW mental demand	Demandingness	Level	Stressfulness	EEW Category assigned
Providing Consultation and Advice	0.434	0.396	0.455	0.448	0.357	0.357	0.495	0.412	1
Scheduling Work and Activities	0.120	0.326	0.789	0.524	0.222	0.377	0.432	0.452	1
Resolving Conflicts	0.262	0.645	0.433	0.621	0.138	0.462	0.146	0.334	2
Negotiating with Others	– 0.005	0.440	0.165	0.719	0.102	0.196	0.088	0.214	2
Coordinating Work and Activities	0.348	0.814	0.130	0.714	0.314	0.075	0.043	0.763	2
Guiding, Directing, and Motivating Subordinates	0.155	0.910	0.207	0.672	0.182	0.101	– 0.078	0.644	2
Getting Information	0.889	0.228	– 0.071	0.234	0.726	0.310	0.620	0.131	3
Evaluating Information	0.705	– 0.115	0.257	0.005	0.582	0.501	0.888	0.033	3
Interpreting the Meaning of Information	0.741	0.225	0.199	0.333	0.759	– 0.088	0.882	0.111	3
Updating and Using Relevant Knowledge	0.702	0.217	0.184	0.213	0.725	0.294	0.773	0.114	3
Developing Objectives and Strategies	0.458	0.264	0.409	0.292	0.170	0.803	0.347	0.408	4
Analysing Information	0.400	0.340	0.398	0.377	0.402	0.432	0.649	0.355	4

2.5 Statistical analyses

All statistical analyses employed an alpha level for statistical significance of 0.05 (two-tailed) and were performed using IBM SPSS Statistics (version 20 [22]). Comparison of the characteristics between study participants whose questionnaires were included and excluded from analysis was accomplished using the Pearson Chi-square Test and the Mann-Whitney-U-Test.

The factor structure of the EEW mental demands was investigated via exploratory factor analysis. We ran three factor analyses: one for the level of the EEW mental demands, one for the demandingness of the EEW mental demands, and one for the stressfulness of each EEW demand. The purpose of the exploratory factor analyses was to verify whether the factor structures of level, demandingness, and stressfulness were similar. This exploratory factor analysis provided us more information of the underlying factor structure than a confirmatory factor analysis, which only estimates the fit of the structure. Based on the observed factor structure, we assigned each EEW mental demand to an EEW category.

In order to test the associations between the level of EEW mental demands and stress and burnout, we calculated the Pearson’s correlation, linear regression analysis adjusted for age, gender, and education, and structural equation models (SEM) using PROCESS (www.afhayes.com). For purpose of analysis, the variables were z-transformed to achieve normal distribution and to make the scales comparable. With regard to Hypothesis 1, we first investigated whether a high level for each EEW category was also perceived as demanding and stressful. The corresponding SEM model comprised a direct effect from level to stressfulness and an indirect effect from level via demandingness to stressfulness. With regard to Hypothesis 2, we then investigated whether a high level for each EEW category was associated with burnout and whether this was moderated by the perceived levels of demandingness and stressfulness. The corresponding SEM model comprised a direct effect from level to burnout, and two indirect effects: (i) from level via demandingness to burnout and (ii) from level via stressfulness to burnout.

3 Results

The means for frequency, level, demandingness, and stressfulness of each EEW mental demands are shown in Table 1. The most frequently performed EEW mental demand was ‘Updating and Using Relevant Knowledge’ (4.57, SD 0.66), and the least frequently was ‘Negotiating with Others’ (3.07, SD 1.45). The highest level was reported for the EEW mental demand ‘Interpreting the Meaning of Information’ (3.59, SD 1.17) and the lowest level for ‘Scheduling Work and Activities’ (2.67, SD 1.06) and ‘Developing Objectives and Strategies’ (2.67, SD 1.01). Interestingly, the highest perceived demandingness was reported for ‘Developing Objectives and Strategies’ (3.93, SD 0.83), whereas the lowest perceived demandingness was reported for ‘Coordinating Work and Activities’ (3.20, SD 1.07). The highest perceived stressfulness was reported for ‘Resolving conflicts’ (3.33, SD 0.92) and the lowest for ‘Providing Consultation and Advice’ (2.17, SD 0.77).

3.1 Factor structure of the EEW mental demands

We explored the factor structure of the level, demandingness, and stressfulness of the EEW mental demands. Factor analysis revealed three factors for the level and demandingness and two factors for stressfulness; as supported by inflection points on the scree plot and factor loadings (results shown in Table 2). Certain groups of EEW mental demands landed on the same factors for level, demandingness, and stressfulness (see Table 2) – correspondingly the factor structure of level, demandingness, and stressfulness was comparable. Based on this factor structure, we assigned four EEW Categories: EEW category 1 comprised ‘Providing Consultation and Advice’ and ‘Scheduling Work and Activities’; EEW category 2 comprised ‘Resolving Conflicts’, ‘Negotiating with Others’, ‘Coordinating Work and Activities’, and ‘Guiding, Directing, and Motivating Subordinates’; EEW category 3 comprised ‘Getting Information’, ‘Evaluating Information’, ‘Interpreting the Meaning of Information’, and ‘Updating and Using Relevant Knowledge’; and EEW category 4 comprised ‘Developing Objectives and Strategies’ and ‘Analysing Information’.

3.2 Hypothesis 1: Level of EEW mental demands and stress

We tested the hypothesis that higher levels in EEW mental demands are associated with higher stressfulness. Table 3 shows the means of perceived level, demandingness, and stressfulness of each EEW category. The highest level was observed in EEW category 3, the highest demandingness and the highest stressfulness in both EEW categories 2 and 4. The level was always positively correlated with demandingness except in EEW category 4. The level was only correlated with stressfulness in EEW category 2, and not in any other categories. Demandingness was always positively correlated with stressfulness.

Linear regression analysis adjusted for age, gender, and education indicated significant associations between high demandingness and high stressfulness for every EEW category, but a high level was not significantly associated with stressfulness (see Table 4).

Table 3
Means and correlations of the Enriched Environment at Work (EEW) categories

Characteristics of the EEW EEW Category 1 EEW Category 2 EEW Category 3 EEW Category 4

Category (M, SD) (M, SD) (M, SD) (M, SD)

Level 2.88 (0.14) 2.84 (0.14) 3.25 (0.13) 2.85 (0.13)

Demandingness 3.64 (0.10) 3.38 (0.12) 3.54 (0.11) 3.74 (0.11)

Stressfulness 2.43 (0.10) 2.80 (0.09) 2.32 (0.11) 2.73 (0.11)

Characteristics of the EEW EEW Category 1 EEW Category 2 EEW Category 3 EEW Category 4

Category (Correlation¹) (Correlation¹) (Correlation¹) (Correlation¹)

Level – Demandingness 00.544^ 0.779^ 00.532^ 0.254

Level – Stressfulness 0.278 0.453^ 0.187 0.105

Level – Personal Burnout 0.094 0.055 0.050 0.013

Level – Work Burnout – 0.001 0.075 0.081 – 0.021

Level – Overall Stress 0.289 0.369^* 0.201 0.109

Demandingness – Stressfulness 00.532^ 0.567^ 0.371^* 00.404^

Demandingness – Personal Burnout 0.134 0.095 0.123 0.055

Demandingness – Work Burnout 0.229 0.114 0.151 0.108

Demandingness – Overall Stress 00.454^ 0.334^* 0.238 0.224

Stressfulness – Personal Burnout 0.362^* 0.380^** 0.279 00.366^*

Stressfulness – Work Burnout 00.383^ 0.389^ 00.479^ 000.495^

Characteristics of the EEW	EEW Category 1	EEW Category 2	EEW Category 3	EEW Category 4
Level	2.88 (0.14)	2.84 (0.14)	3.25 (0.13)	2.85 (0.13)
Demandingness	3.64 (0.10)	3.38 (0.12)	3.54 (0.11)	3.74 (0.11)
Stressfulness	2.43 (0.10)	2.80 (0.09)	2.32 (0.11)	2.73 (0.11)

Characteristics of the EEW	EEW Category 1	EEW Category 2	EEW Category 3	EEW Category 4
Level – Demandingness	00.544^**	0.779^**	00.532^**	0.254
Level – Stressfulness	0.278	0.453^**	0.187	0.105
Level – Personal Burnout	0.094	0.055	0.050	0.013
Level – Work Burnout	– 0.001	0.075	0.081	– 0.021
Level – Overall Stress	0.289	0.369^*	0.201	0.109
Demandingness – Stressfulness	00.532^**	0.567^**	0.371^*	00.404^**
Demandingness – Personal Burnout	0.134	0.095	0.123	0.055
Demandingness – Work Burnout	0.229	0.114	0.151	0.108
Demandingness – Overall Stress	00.454^**	0.334^*	0.238	0.224
Stressfulness – Personal Burnout	0.362^*	0.380^**	0.279	00.366^*
Stressfulness – Work Burnout	00.383^**	0.389^**	00.479^**	000.495^**

Notes: 1 – correlation of the z-transformed scores according to Pearson; ^*– level of significance is <0.05; ^** – level of significance is <0.01; M – mean; SD – standard deviation.

The results of the structural equation models confirmed that a high level was not significantly related to stressfulness. A high level showed indirect associations via demandingness with higher stressfulness (see Table 5) for EEW categories 1 and 2. For EEW categories 3 and 4, only demandingness predicted stressfulness, and the level was non-significant (for the indirect as well as total effect).

3.3 Hypothesis 2: Level of EEW mental demands and burnout

We tested the hypothesis that higher levels in EEW mental demands are associated with burnout. We observed no correlation between the level of every EEW category and neither personal burnout, nor work burnout (Table 3). Only, stressfulness was positively correlated with both burnout scores.

Linear regression analysis adjusted for age, gender, and education affirmed the significant associations between higher stressfulness and higher burnout scores. Stressfulness of the EEW category 4 was not significant for personal burnout, and stressfulness of the EEW category 1 was not significant for work burnout. Correlations between level and burnout scores as well as between demandingness and burnout scores were not significant.

The results of the structural equation models confirmed the findings of the linear regression analyses, demonstrating that higher stressfulness predicted higher burnout scores for EEW categories 2, 3 and 4 – however, not for EEW category 1. There was no significant effect (indirect or direct) from level to burnout.

Table 4
Coefficients of the regression analyses of the impact of the level of EEW mental demands on stressfulness and burnout

Model Characteristic of the EEW Category EEW Category 1 (ß, CI95%) p EEW Category 2 (ß, CI95%) p EEW Category 3 (ß, CI95%) p EEW Category 4 (ß, CI95%) p

Models on Stressfulness

Model 1 Level 0.28 (– 0.01– 0.57) 0.061 0.45 (0.18– 0.72) 0.002 0.19 (– 0.11– 0.49) 0.214 0.11 (– 0.20– 0.41) 0.489

Level^* 0.30 (– 0.01– 0.60) 0.054 0.45 (0.16– 0.74) 0.003 0.21 (– 0.11– 0.53) 0.186 0.08 (– 0.22– 0.31) 0.601

Model 2 Level – 0.02 (– 0.33– 0.29) 0.917 0.03 (– 0.37– 0.43) 0.882 – 0.02 (– 0.35– 0.32) 0.927 0.00 (– 0.29– 0.29) 0.989

Demandingness 0.54 (0.23– 0.85) 0.001 0.54 (0.14– 0.95) 0.010 0.38 (0.04– 0.72) 0.028 0.40 (0.11– 0.69) 0.008

Level^* – 0.00 (– 0.33– 0.33) 0.994 0.07 (– 0.37– 0.51) 0.738 – 0.02 (– 0.38– 0.35) 0.928 – 0.01 (– 0.29– 0.27) 0.927

Demandingness^* 0.53 (0.20– 0.85) 0.002 0.49 (0.04– 0.94) 0.033 0.40 (0.04– 0.76) 0.031 0.41 (0.11– 0.71) 0.009

Models on Personal Burnout

Model 1 Level 0.94 (– 0.30– 0.40) 0.536 0.06 (– 0.25– 0.36) 0.716 0.05 (– 0.25– 0.35) 0.742 0.01 (– 0.29– 0.32) 0.934

Level^* 0.12 (– 0.18– 0.42) 0.424 – 0.00 (– 0.31– 0.30) 0.988 0.02 (– 0.29– 0.33) 0.908 – 0.01 (– 0.30– 0.28) 0.942

Model 2 Level 0.04 (– 0.31– 0.38) 0.835 – 0.06 (– 0.52– 0.39) 0.783 – 0.02 (– 0.37– 0.34) 0.921 – 0.00 (– 0.30– 0.30) 0.987

Demandingness – 0.10 (– 0.49– 0.29) 0.604 – 0.13 (– 0.62– 0.36) 0.597 0.03 (– 0.34– 0.41) 0.865 – 0.11 (– 0.43– 0.21) 0.497

Stressfulness 0.41 (0.06– 0.75) 0.021 0.48 (0.14– 0.83) 0.007 0.27 (– 0.05– 0.59) 0.098 0.41 (0.10– 0.73) 0.012

Level^* 0.10 (– 0.24– 0.45) 0.552 – 0.05 (– 0.51– 0.40) 0.814 – 0.15 (– 0.50– 0.20) 0.394 – 0.03 (– 0.32– 0.27) 0.863

Demandingness^* – 0.17 (– 0.55– 0.22) 0.391 – 0.22 (– 0.71– 0.27) 371 0.18 (– 0.19– 0.54) 0.335 – 0.05 (– 0.39– 0.30) 0.784

Stressfulness^* 0.37 (0.03– 0.70) 0.032 0.49 (0.16– 0.82) 0.005 0.31 (0.01– 0.62) 0.045 0.33 (– 0.01– 0.66) 0.057

Models on Personal Burnout

Model 1 Level – 0.00 (– 0.31– 0.30) 0.992 0.08 (– 0.23– 0.38) 0.622 0.08 (– 0.22– 0.38) 0.593 – 0.02 (– 0.32– 0.28) 0.892

Level^* 0.03 (– 0.27– 0.33) 0.833 0.09 (– 0.21– 0.39) 0.539 0.07 (– 0.24– 0.37) 0.666 – 0.04 (– 0.33– 0.26) 0.804

Model 2 Level – 0.17 (– 0.51– 0.17) 0.307 – 0.05 (– 0.50– 0.40) 0.826 0.01 (– 0.31– 0.33) 0.957 – 0.05 (– 0.33– 0.23) 0.705

Demandingness 0.13 (– 0.25– 0.52) 0.494 – 0.12 (– 0.61– 0.37) 0.627 – 0.04 (– 0.38– 0.31) 0.832 – 0.10 (– 0.40– 0.20) 0.519

Stressfulness 0.36 (0.03– 0.70) 0.035 0.48 (0.13– 0.82) 0.008 0.49 (0.20– 0.79) 0.002 0.54 (0.25– 0.83) 0.001

Level^* – 0.12 (– 0.47– 0.22) 0.476 0.03 (– 0.42– 0.48) 0.878 – 0.12 (– 0.43– 0.20) 0.462 – 0.06 (– 0.34– 0.22) 0.654

Demandingness^* 0.11 (– 0.27– 0.49) 0.548 – 0.21 (– 0.69– 0.28) 0.399 0.14 (– 0.19– 0.47) 0.391 – 0.03 (– 0.36– 0.29) 0.831

Stressfulness^* 0.30 (– 0.04– 0.63) 0.079 0.48 (0.15– 0.81) 0.005 0.48 (0.20– 0.79) 0.001 0.44 (0.12– 0.75) 0.008

Model	Characteristic of the EEW Category	EEW Category 1 (ß, CI95%)	p	EEW Category 2 (ß, CI95%)	p	EEW Category 3 (ß, CI95%)	p	EEW Category 4 (ß, CI95%)	p
Models on Stressfulness
Model 1	Level	0.28 (– 0.01– 0.57)	0.061	0.45 (0.18– 0.72)	0.002	0.19 (– 0.11– 0.49)	0.214	0.11 (– 0.20– 0.41)	0.489
	Level^*	0.30 (– 0.01– 0.60)	0.054	0.45 (0.16– 0.74)	0.003	0.21 (– 0.11– 0.53)	0.186	0.08 (– 0.22– 0.31)	0.601
Model 2	Level	– 0.02 (– 0.33– 0.29)	0.917	0.03 (– 0.37– 0.43)	0.882	– 0.02 (– 0.35– 0.32)	0.927	0.00 (– 0.29– 0.29)	0.989
	Demandingness	0.54 (0.23– 0.85)	0.001	0.54 (0.14– 0.95)	0.010	0.38 (0.04– 0.72)	0.028	0.40 (0.11– 0.69)	0.008
	Level^*	– 0.00 (– 0.33– 0.33)	0.994	0.07 (– 0.37– 0.51)	0.738	– 0.02 (– 0.38– 0.35)	0.928	– 0.01 (– 0.29– 0.27)	0.927
	Demandingness^*	0.53 (0.20– 0.85)	0.002	0.49 (0.04– 0.94)	0.033	0.40 (0.04– 0.76)	0.031	0.41 (0.11– 0.71)	0.009
Models on Personal Burnout
Model 1	Level	0.94 (– 0.30– 0.40)	0.536	0.06 (– 0.25– 0.36)	0.716	0.05 (– 0.25– 0.35)	0.742	0.01 (– 0.29– 0.32)	0.934
	Level^*	0.12 (– 0.18– 0.42)	0.424	– 0.00 (– 0.31– 0.30)	0.988	0.02 (– 0.29– 0.33)	0.908	– 0.01 (– 0.30– 0.28)	0.942
Model 2	Level	0.04 (– 0.31– 0.38)	0.835	– 0.06 (– 0.52– 0.39)	0.783	– 0.02 (– 0.37– 0.34)	0.921	– 0.00 (– 0.30– 0.30)	0.987
	Demandingness	– 0.10 (– 0.49– 0.29)	0.604	– 0.13 (– 0.62– 0.36)	0.597	0.03 (– 0.34– 0.41)	0.865	– 0.11 (– 0.43– 0.21)	0.497
	Stressfulness	0.41 (0.06– 0.75)	0.021	0.48 (0.14– 0.83)	0.007	0.27 (– 0.05– 0.59)	0.098	0.41 (0.10– 0.73)	0.012
	Level^*	0.10 (– 0.24– 0.45)	0.552	– 0.05 (– 0.51– 0.40)	0.814	– 0.15 (– 0.50– 0.20)	0.394	– 0.03 (– 0.32– 0.27)	0.863
	Demandingness^*	– 0.17 (– 0.55– 0.22)	0.391	– 0.22 (– 0.71– 0.27)	371	0.18 (– 0.19– 0.54)	0.335	– 0.05 (– 0.39– 0.30)	0.784
	Stressfulness^*	0.37 (0.03– 0.70)	0.032	0.49 (0.16– 0.82)	0.005	0.31 (0.01– 0.62)	0.045	0.33 (– 0.01– 0.66)	0.057
Models on Personal Burnout
Model 1	Level	– 0.00 (– 0.31– 0.30)	0.992	0.08 (– 0.23– 0.38)	0.622	0.08 (– 0.22– 0.38)	0.593	– 0.02 (– 0.32– 0.28)	0.892
	Level^*	0.03 (– 0.27– 0.33)	0.833	0.09 (– 0.21– 0.39)	0.539	0.07 (– 0.24– 0.37)	0.666	– 0.04 (– 0.33– 0.26)	0.804
Model 2	Level	– 0.17 (– 0.51– 0.17)	0.307	– 0.05 (– 0.50– 0.40)	0.826	0.01 (– 0.31– 0.33)	0.957	– 0.05 (– 0.33– 0.23)	0.705
	Demandingness	0.13 (– 0.25– 0.52)	0.494	– 0.12 (– 0.61– 0.37)	0.627	– 0.04 (– 0.38– 0.31)	0.832	– 0.10 (– 0.40– 0.20)	0.519
	Stressfulness	0.36 (0.03– 0.70)	0.035	0.48 (0.13– 0.82)	0.008	0.49 (0.20– 0.79)	0.002	0.54 (0.25– 0.83)	0.001
	Level^*	– 0.12 (– 0.47– 0.22)	0.476	0.03 (– 0.42– 0.48)	0.878	– 0.12 (– 0.43– 0.20)	0.462	– 0.06 (– 0.34– 0.22)	0.654
	Demandingness^*	0.11 (– 0.27– 0.49)	0.548	– 0.21 (– 0.69– 0.28)	0.399	0.14 (– 0.19– 0.47)	0.391	– 0.03 (– 0.36– 0.29)	0.831
	Stressfulness^*	0.30 (– 0.04– 0.63)	0.079	0.48 (0.15– 0.81)	0.005	0.48 (0.20– 0.79)	0.001	0.44 (0.12– 0.75)	0.008

Notes: ^* – adjusted for age, gender, education; CI – confidence interval; p – level of significance; β – regression coefficient; bold – the level of significance is p < 0.05.

Table 5

Coefficients of the structural equation models of the impact of the level of EEW mental demands on stressfulness and burnout

Model	Characteristic of the EEW Category	EEW Category 1 (ß, CI95%)	p	EEW Category 2 (ß, CI95%)	p	EEW Category 3 (ß, CI95%)	p	EEW Category 4 (ß, CI95%)	p
Models on Stressfulness
Direct Effect	Level	– 0.02 (– 0.24– 0.21)	0.887	0.03 (– 0.34– 0.40)	0.870	– 0.02 (– 0.41– 0.37)	0.937	0.00 (– 0.33– 0.34)	0.991
Indirect Effect	Level – Demandingness	0.54 (0.21– 0.88)	0.002	0.78 (0.57– 0.99)	0.000	0.53 (0.26– 0.80)	0.000	0.25 (– 0.05– 0.55)	0.095
	Demandingness	0.54 (0.22– 0.86)	0.001	0.54 (0.17– 0.92)	0.005	0.38 (0.00– 0.76)	0.049	0.40 (0.15– 0.65)	0.002
	Test for demandingness	0.295	0.020	0.423	0.007	0.202	0.078	0.103	0.145
Total Effect	Level	0.28 (0.01– 0.55)	0.045	0.45 (0.13– 0.77)	0.007	0.19 (– 0.09– 0.46)	0.178	0.10 (– 0.22– 0.43)	0.521
Models on Personal Burnout
Direct Effect	Level	0.04 (– 0.27– 0.35)	0.816	– 0.06 (– 0.54– 0.42)	0.796	– 0.02 (– 0.47– 0.44)	0.939	– 0.00 (– 0.23– 0.26)	0.985
Indirect Effect	Level – Demandingness	0.54 (0.21– 0.88)	0.002	0.78 (0.57– 0.99)	0.000	0.53 (0.26– 0.80)	0.000	0.25 (– 0.05– 0.55)	0.095
	Level – Stressfulness	0.28 (0.01– 0.55)	0.045	0.45 (0.13– 0.77)	0.007	0.19 (– 0.09– 0.46)	0.178	0.10 (– 0.22– 0.43)	0.521
	Demandingness	– 0.10 (– 0.70– 0.50)	0.734	– 0.13 (– 0.68– 0.42)	0.635	0.03 (– 0.39– 0.45)	0.879	– 0.11 (– 0.45– 0.23)	0.520
	Stressfulness	0.41 (– 0.05– 0.86)	0.080	0.48 (0.09– 0.87)	0.017	0.27 (0.02– 0.52)	0.033	0.41 (0.22– 0.60)	0.000
	Test for demandingness	– 0.055	0.744	– 0.101	0.637	0.017	0.883	– 0.028	0.595
	Test for Stressfulness	0.113	0.203	0.218	0.070	0.050	0.278	0.043	0.533
Total Effect	Level	0.09 (– 0.18– 0.37)	0.492	0.06 (– 0.23– 0.34)	0.701	0.05 (– 0.30– 0.40)	0.776	0.01 (– 0.26– 0.29)	0.927
Models on Work Burnout
Direct Effect	Level	– 0.17 (– 0.54– 0.19)	0.342	– 0.05 (– 0.57– 0.47)	0.849	0.01 (– 0.39– 0.40)	0.965	– 0.05 (– 0.32– 0.21)	0.691
Indirect Effect	Level – Demandingness	0.55 (0.21– 0.88)	0.002	0.78 (0.57– 0.99)	0.000	0.53 (0.26– 0.80)	0.000	0.25 (– – 0.05– 0.55)	0.095
	Level – Stressfulness	0.28 (0.01– 0.55)	0.045	0.45 (0.13– 0.77)	0.007	0.19 (– 0.09– 0.46)	0.178	0.10 (– 0.22– 0.43)	0.521
	Demandingness	0.13 (– 0.41– 0.67)	0.625	– 0.12 (– 0.66– 0.42)	0.657	– 0.04 (– 0.40– 0.33)	0.841	– 0.10 (– 0.38– 0.19)	0.496
	Stressfulness	0.36 (– 0.10– 0.82)	0.121	0.48 (0.12– 0.84)	0.010	0.49 (0.19– 0.79)	0.002	0.54 (0.23– 0.85)	0.001
	Test for demandingness	0.072	0.641	– 0.093	0.658	– 0.019	0.845	– 0.025	0.577
	Test for Stressfulness	0.101	0.241	0.217	0.058	0.092	0.224	0.057	0.539
Total Effect	Level	– 0.00 (– 0.32– 0.32)	0.993	0.08 (– 0.24– 0.39)	0.637	0.08 (– 0.27– 0.44)	0.648	– 0.02 (– 0.36– 0.32)	0.903

Notes: CI – confidence interval; p – level of significance; β – regression coefficient; bold – the level of significance is p < 0.05.

4 Discussion

The aim of our study was to verify that higher perceived levels in EEW mental demands are associated with a higher subjectively perceived stress (Hypothesis 1) but not with a higher burnout score (Hypothesis 2). The results suggested that the associations are demand-specific: Higher levels in the EEW category 1 (‘Providing Consultation and Advice’, ‘Scheduling Work and Activities’) were significantly associated with higher stress, but not with burnout (supporting Hypotheses 1 and 2). Higher levels in EEW category 2 (‘Resolving Conflicts’, ‘Negotiating with Others’, ‘Coordinating Work and Activities’, ‘Guiding, Directing, and Motivating Subordinates’) were significantly associated with higher stress (supporting Hypothesis 1), and the higher stress was then significantly associated with higher burnout scores. The level was not directly related to burnout; the indirect pathway via stressfulness was approaching significance (p = 0.058). Since the sample size was rather small, it is unclear whether this is a Type II error and we should not entirely reject Hypothesis 2. The other two EEW categories 3 and 4 (3: ‘Getting Information’, ‘Evaluating Information’, ‘Interpreting the Meaning of Information’, ‘Updating and Using Relevant Knowledge’; 4: ‘Developing Objectives and Strategies’, ‘Analysing Information’.) that were not related to higher stress (rejecting Hypothesis 1), but higher perceived stress was significantly associated to higher burnout scores (rejecting Hypothesis 2). Our results therefore imply that (i) high levels in EEW categories 1 and 2 may actually cause higher stress, and that (ii) this is not the case for the EEW categories 3 and 4. However, higher perceived stressfulness of EEW categories 3 and 4 may increase susceptibility to burnout. Hence, it seems as if the subjectively perceived stress is the major driver of burnout symptoms, and not the high level in EEW mental demands.

One possible reason for high levels in EEW mental demands not being perceived as stressful could be learning effects. If someone is frequently exposed to a mental demand then learning processes take place – as experimental studies using logic, memory, parallel processing or search tasks have demonstrated [24, 25]. Studies have shown that training with high mental demand improves performance to such a degree that the task is processed almost automatically (e.g., [26 –28]). In fact, researchers observed that learning leads to changes in the brain: For instance, training the performance of a task led to more efficient activation of brain areas [29]. Training with spatial mental demands enhanced white matter plasticity in the brain [30]. Memory training increased cortical thickness [31] and working memory training led to a better structural connectivity and more efficient neurotransmitter functioning [32]. Learning to perform at higher levels could thus adapt the brain to master those demands. In this way, higher demand levels are not perceived as stressful anymore. In our study, only high levels of EEW categories 1 and 2, but not 3 and 4 were perceived as stressful. The EEW categories 1 and 2 involve consultation, coordinating, and scheduling. Performing these tasks is less predictable, involves more conflicts, and is resource-dependent. Even if somebody learns to perform these tasks at a high level, it may not be possible to perform them without hassles. In fact, having insufficient control [33] and insufficient resources are important causes of adverse effects of work stress [34]. Hence, if the performance of an EEW mental demand depends on other work conditions, then high levels in these demands may cause stress. Further studies are necessary to validate this assumption.

Another possible reason that high levels in EEW mental demands were not perceived as stressful but could be selection effects. Ideally, an individual is ‘selected’ to be working in a job that matches his or her skills. The level of EEW mental demands at work may thus be suitable for his or her skills and will therefore not be experienced as stressful. If this was the case, however, then it does not explain why the overall stress levels of the participants were high. Neither does it explain why some high levels of EEW mental demands were perceived as more stressful than others.

High levels of EEW mental demands were also not related to burnout, as our findings indicate. The fact that burnout symptoms instead seem to be associated with perceived stressfulness supports the theory by Maslach [15], which asserts that the major cause of burnout is a misfit between the worker and the job. Such a misfit may be reflected by a high degree of subjectively perceived stress. It could be argued that burnout symptoms have also shown to be caused by work conditions such as noise, depersonalization, and personal fulfilment [35], as well as difficulties with job task identity, lack of autonomy or information, and a poor organizational climate [16, 36]. The compensatory effort that is necessary to overcome such challenging work conditions – like getting permission, researching information, or requesting access to additional resources – results in more stress. Compensatory efforts may also be required to overcome constraints on the emotional system (e.g., negative feedback), which disturb mental information processing and increase the amount of mental effort necessary to maintain an optimal task performance [37]. It is compensatory efforts like these that bring about physical and psychological constraints that can lead to burnout [6]. Accordingly, it is the subjectively experienced efforts an individual is forced to make, and manifests as higher stress, that trigger burnout, but not being exposed to a high level.

Our study is not without limitations. First, our study is just a first exploratory study and the sample is rather small. Thus, the estimated parameters may not be precise and either undermine the true effects or overestimate effect sizes. The findings should be validated in a larger age-stratified sample. Second, we conducted a cross-sectional study. A longitudinal observation would give additional information on intra-individual differences and on changes in the stress and burnout scores over time. Finally, the levels of mental demands were self-reported and may differ slightly from objective estimates (e.g. as assessed through job analysis software).

5 Conclusion

Previous studies suggested that high levels of EEW mental demands can protect against cognitive decline in old age and against dementia [1, 2]. The idea of applying high levels of EEW mental demands within preventative initiatives is constrained by the concern that they may accelerate stress and cause burnout. The findings of our first exploratory study suggested that high levels of EEW mental demands may not necessarily be related to stress and to burnout symptoms. It is therefore worth exploring the possibilities of how EEW mental demands can be integrated in preventative initiatives at the workplace. Future studies should not only validate the findings in larger samples but also across different occupational groups. Future studies may also determine whether the cognitive outcome is the same depending on how well a person is matched to his job, as the same demand may be enjoyed by some people and perceived as stressful by others. Experimental interventions could evaluate the protective potential of EEW mental demands against cognitive decline. As each person seems to perceive stress and demands in their own way, findings may be specific to those factors that influence those subjective perceptions. Experimental designs may even compare the subjectively perceived stress levels to physical stress reactions and how this relates to cognitive functioning in the long run. More information is required on how mental demands turn out to be a protective factor for minimizing the risk of age-related dementia.

Lower birth rates and higher life expectancies due to medical advances and improved living conditions has led to aging societies. With a greater proportion of elderly individuals in the society, mental demands at work could be of great relevance to sustain a good cognitive functioning in old age. Since physically demanding work conditions are challenging to elderly workers [38], mentally demanding work conditions may perhaps be an opportunity to stay productive for a longer lifetime period [39]. Organizations who want to provide a mentally stimulating work environment could enhance activities such as scheduling, negotiating, coordinating, evaluating, and analysing, while minimizing high levels of stress.

Conflict of interest

None to report.

Footnotes

Appendix

Table A2

Definitions

Enriched Environment at Work (EEW)	a work environment that is enriched with mental demands that have shown to protect against cognitive decline and dementia
Frequency	how often the mental demand is performed at work
Level	at what level of the mental demand has to be performed at work
Demandingness	how demanding the mental demand is perceived
Stressfulness	how stressful the mental demand is perceived
EEW category 1	the mental demands ‘Providing Consultation and Advice’ and ‘Scheduling Work and Activities’
EEW category 2	the mental demands ‘Resolving Conflicts’, ‘Negotiating with Others’, ‘Coordinating Work and Activities’, and ‘Guiding, Directing, and Motivating Subordinates’
EEW category 3	the mental demands ‘Getting Information’, ‘Evaluating Information’, ‘Interpreting the Meaning of Information’, and ‘Updating and Using Relevant Knowledge’
EEW category 4	the mental demands ‘Developing Objectives and Strategies’ and ‘Analysing Information’
Burnout	state of physical, emotional and mental exhaustion resulting from work situations
personal burnout	general condition of physical and psychological exhaustion
work-related burnout	exhaustion related to work only
Work conditions
Job task identity ^*s3	experienced meaningfulness of completing an identifiable piece of work
Task significance	experienced meaningfulness of whether the job has impact on the life of others
Autonomy	degree of freedom and independence to determine the procedures of carrying out the job
Lack of feedback	lack of information on the outcome of the work
Resources	motivational processes, organisational and contextual factors that support the accomplishment of the work
Organizational climate	perception about practices and procedures in an organization

Acknowledgments

This study was supported by the Medical Faculty of the University of Leipzig under a junior research grant No. 971000-084; and LIFE (Leipzig Research Centre for Civilization Diseases at the Universität Leipzig which is funded by means of the European Social Fund and the Free State of Saxony, Germany) under grant No. LIFE103-P1.

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