A Multimodal Prevention Program for Stress Reduction

Results of a Randomized Controlled Trial

Background: Stress-reducing preventive measures and the elements of which they are made up have been inadequately studied to date. In this trial, we studied the stress experienced over the twelve months from the beginning of the intervention by subjects who underwent a two-week-long multimodal prevention program for stress reduction with a psycho-educative component, with a refresher at six months, compared to that experienced by subjects in two control groups (CG-B: prevention program without psychoeducation, CG-C: no intervention).

Methods: Adults with an elevated stress exposure who were at risk of stress-induced health impairment were the subjects of a prospective, three-armed, randomized controlled trial. The subjects who participated in the two preventive programs (IG [intervention group], CG-B) traveled to a health resort. They were blinded with respect to their group assignment and the content of their intervention. The primary outcomes were subjectively experienced stress (Perceived Stress Questionnaire, PSQ) and chronic stress experience (Screening scale of the Trier Inventory for Chronic Stress, TICS-SSCS), assessed one, three, six, and twelve months after the start of the intervention. The groups were compared with univariate and multivariate analyses. Trial registry number: DRKS00011290.

Results: Among 120 candidates who expressed interest in participation and were randomly allotted to one of the three groups, 87 persons (67.8% female) with a mean age of 50.5 years (SD 8.8 years) were included in the study. Subjects in the IG with psychoeducation had a lower degree of perceived stress at twelve months than those in either one of the control groups, with controlling for baseline values, as measured by both of the instruments used: PSQ (ANCOVA: F[2, 77] = 11.77; p < 0.001, strong effect: ηp² = 0.234) and TICS-SSCS (ANCOVA: F[2, 78] = 3.93; p = 0.024, moderate effect: ηp² = 0.091).

Conclusion: This exploratory trial reveals a lessening of subjectively experienced stress after participation in a two-part prevention program for stress reduction with a specific psychoeducative component.

The development, causes, and effects of stress have long been the subject of scientific investigations, and there are a number of different concepts and explanatory models for its emergence and impact. According to Lazarus’ transactional model of stress, a person appraises situations as irrelevant (non-stressful), positive (non-stressful), or burdensome (stressful) (1, 2). The possibility to cope with a stressful situation or with stressors is analyzed based on the available resources and, in the case of inadequate coping options, results in stress. Individual resources can differ. These include, for example, social networks, the coping behaviors one has available, or expectations of self-efficacy (3). They can be strengthened and, together with effective methods, contribute to addressing possible stressors. This can reduce stress, and the evocation of stress responses can be prevented, as can their resulting in chronic impairments in the long term (4).

Representative surveys conducted by a German statutory health insurance fund, the Techniker Krankenkasse (TK), showed rising stress levels among German adults as well as a negative relationship between stress and health in the period 2013–2021 (5). In 2021, 26% of respondents reported frequently feeling stressed, while in 2013 this figure was 20%. Frequently stressed individuals cited mental health problems significantly more often (39%) compared to less stressed individuals (9–13%). In addition to negative effects on mental functioning, long-term stress also impacts the immune system as well as the cardiovascular, gastroenterological, and cognitive systems (6). The negative effects of stress impact not only individuals but also place a burden on companies and national economies. Mental health disorders reduce performance, increase absenteeism (7), and are the commonest cause of early retirement in Germany (8).

The TK study on stress points to a likely interaction between stress and health. According to the study, an increased level of stress appears to have a negative effect on health, while at the same time poor health status likely causes an increased perception of stress. Therefore, the study recommends prevention programs for stress reduction (5). The corresponding preventive measures are intended to strengthen individual/personal or situational resources (9). Ideally, the health prevention program is multimodal, that is to say, more effective than a single-topic intervention (10), and ensures a sustained effect through a refresher intervention (11). Informative studies are required to generate additional evidence on the mode of action of programs of this kind.

The aim of the trial was to evaluate a multimodal 2-week prevention program for stress reduction with a psychoeducational component and a refresher course after 6 months. To this end, we analyzed the extent to which participants’ subjective experience of stress and chronic experience of stress changed within 12 months of the start of the intervention compared to two control groups. Subjectively perceived stress was measured using the Perceived Stress Questionnaire (PSQ), while the chronic stress experience was recorded using the Screening Scale of the Trier Inventory for Chronic Stress (TICS-SSCS).

The hypothesis was that: At 1, 3, 6, and 12 months, there are differences in the mean values of the PSQ, the TICS-SSCS, and salivary cortisol levels.

Methods

Trial design

A three-armed, randomized controlled monocentric trial (RCT) with a parallel group design was conducted.

Trial population

Adults with elevated stress exposure who were at risk of developing a stress-induced health impairment were included (12). Stress levels were measured in an online survey using the TICS-SSCS (13) and the Maslach Burnout Inventory (MBI) (14). Individuals with burnout syndrome as well as those with acute disorders requiring treatment were excluded (eMethods).

Participants were recruited primarily in Bavaria, Germany, via local print and online media. The sample size estimate, taking into consideration a drop-out rate of 15%, yielded a case number of 100 subjects that needed to be recruited (eMethods).

The Ethics Committee of the Ludwig Maximilian University of Munich, Germany, granted its approval according to the Declaration of Helsinki (trial number 247–15; 27.05.2015). The trial was registered following its initiation (German Registry of Clinical Trials No.: DRKS00011290; 15.11.2016). Compared to the ethics application, both mental health endpoints were identical. The recording of a physiological parameter (salivary cortisol level) was dropped.

Interventions and control constellation

Figure 1 shows the three trial groups and the interventions carried out with each group. The intervention group (IG) and a control group (CG-B) each traveled, at staggered intervals, to the health resort of Bad Birnbach, Germany, for 2 weeks. There, they took part in the “Active against exhaustion and stress” (Aktiv gegen Erschöpfung und Stress, AGES) program, comprising: psychoeducational seminars, relaxation and exercise components, and thermal water treatments. Participants in the IG received a psychoeducational seminar, while participants in the CG-B received two 90-min talks on the subject of “stress.” Both groups returned to the health resort after 6 months for a 4-day refresher course either with or without a seminar (Figure 1, eMethods, eTable 1).

Figure 1

Trial groups and the measures carried out

eTable 1

Contents of the prevention program and refresher course as well as personnel qualifications

The psychoeducational seminar is based on the logotherapy approach according to Viktor Frankl and is aimed at reinforcing the individual’s personal resources by seeing the meaning of life and situations or altering attitudes and effectively enhancing cognitive behavioral processes in stressful situations (15). In terms of content, it deals with: recognition and impact of stress, self-perception, as well as altering self-image and self-esteem (eMethods). The personnel carrying out the trial were not blinded.

Participants in the third trial group (CG-C) received no intervention, remained in their usual environment, and took part in the written surveys. The costs incurred by those participating in the intervention were subsidized (eMethods).

Outcomes and survey instruments

The primary outcome measures included subjectively experienced stress (PSQ) (16), chronic stress experience (validated TICS-SSCS) (13), each at 1, 3, 6, and 12 months following the initiation of the intervention, and morning salivary cortisol level (before/after intervention phases). Secondary outcome measures included general well-being (measured with the WHO Five Well-Being Index [WHO-5]) (17), sleep quality (recorded using the Pittsburgh Sleep Quality Index [PSQI]) (18), and subjective health (assessed using the visual analog scale of the European Quality of Life [EQ-VAS]). Survey time points were before the intervention (baseline), directly following, as well as at 1, 3, 6, 7, 9, and 12 months following the start of the intervention. Results on subjective health and cortisol levels are not shown.

Statistical analysis

All participants that had taken part in the baseline survey and at least one follow-up survey were included in the analysis. For the TICS-SSCS, an intention-to-treat (ITT) analysis with data at the time of randomization was performed. Baseline data were descriptively analyzed. For both primary outcome measures, a repeated measures analysis of covariance (ANCOVA) was carried out at the end time point (12 months) (dependent variable [DV]: change from baseline; fixed factor: group membership; covariate: score value to baseline survey). If there was a group difference with p < 0.05, a t-test for independent samples was carried out as a post-hoc test. All results are exploratively reported. Individual missing values were replaced. The statistical programs SAS 9.4 and SPSS Version 27 were used (eMethods Section).

Results

The recruitment of participants began 3 months prior to the start of the intervention phase. Figure 2 shows the flow diagram on the participants included and excluded over the course of the trial (June 2015 to July 2017). The baseline characteristics of the trial groups are summarized in Table 1. Trial participants were predominantly female (67.8%) with a mean age of 50.5 years (standard deviation [SD] 8.8). At the baseline survey, there were differences in the distribution of sexes to the two groups.

Figure 2

Flow diagram of the participants included and randomized over the course of the trial

Table 1

Demographic and outcome parameters of the trial population at the start of the trial

Change from the baseline survey

The results of the ANCOVA of the primary outcome measures at 12 months are presented in Table 2. The requirements for the ANCOVA were verified and fulfilled. When the sociodemographic variables were included in the ANCOVA model, these variables showed no effect on the change in primary outcome measures at the 12-month time point.

Table 2

Results of the covariance analysis (ANCOVA) of the primary outcome measures

All trial groups exhibited improvements in subjectively experienced stress (PSQ) at 12 months following the start of the intervention. The IG showed the largest mean change with a difference of –28.8 compared to baseline (Table 2). When controlled for baseline value, group differences were seen at the 12-month time point (F[2, 77] = 11.77; p < 0.001; partial η² = 0.234). The post-hoc test revealed a greater improvement in the IG compared to the CG-B (mean difference: –12.7 points, 95% confidence interval: [–21.5; –3.8]; p = 0.0006) and the CG-C (mean difference: –25.5 points [–35.3; –15.7]; p < 0.001) (Table 2).

Compared to baseline, chronic stress experience (TICS-SSCS) declined in all three trial groups. The IG achieved the largest mean change with a difference of –11.4 points (eTable 2). When controlled for baseline value, group differences were seen at the end time point (F[2, 78] = 3.93; p < 0.024; partial η² = 0.091). The post-hoc test revealed a greater improvement in the IG compared to the CG-B (mean difference: –8.1 points [–13.5; –2.7]; p = 0.004). The ITT analysis revealed no clear group difference in the reduction in the TICS-SSCS at 12-month follow-up (Table 2).

eTable 2

Mean difference to baseline value in the outcome parameters according to trial groups

Other results

Figure 3 shows the mean trend of the score values over the observation period for all outcome measures. At further follow-up survey time points, there were differences in the PSQ and the TICS-SSCS between the IG and the two control groups. In the WHO-5, the IG achieved greater improvements at the end time point as well as at other survey time points compared to both control groups. In the PSQI, the IG improved at the trial end point compared to the CG-C (eTable 2). No adverse effects were reported over the course of the prevention program.

Figure 3

Development of the mean score values of the outcome measures according to groups and survey time point

Discussion

In our consideration of the results, we focused on the changes in subjectively experienced stress (PSQ) and chronic stress experience (TICS-SSCS) at the 12-month time point. Participants in the multimodal “AGES” prevention program for stress reduction involving a stay at a health resort (IG and CG-B) improved in both outcome measures at 12-month follow-up. Compared to the control group with no intervention, the IG improved in both the PSQ and the TICS-SSCS at the end of the trial—compared to the CG-B, only in relation to the PSQ.

The choice of trial design makes important findings possible with regard to changes in stress experience, sleep, and well-being during and after participation in the multimodal prevention program with and without a psychoeducational seminar. The stress experience is individual, situation-dependent, and can be positively affected through regeneration (2). Therefore, an improvement in subjectively experienced stress (PSQ) was to be expected in both intervention groups, as in comparable studies (20, 21, 22).

The exploratory trial results show a clear improvement in the two outcome measures, PSQ and TICS-SSCS, directly after the intervention as well as a stagnation in the 3- to 6-month time period following the intervention (as can be seen from scores in eTable 2). Following participation in the refresher course, improvements (reduced scores) were once again seen in both outcome measures, which stabilized by the 12-month time point. The reduction in scores could be attributable to the implementation in everyday life of what participants learned and the subsequent opportunity for reflection during the refresher course (psychoeduction seminar). With regard to the variable „chronic stress“ (TICS-SSCS), a time-delayed change is assumed, since this arises from frequent, long, or inadequate stress exposure (23).

More pronounced improvements were seen in the IG following the intervention compared to participants in the modified program (CG-B). Since the prevention programs differed only in terms of the seminar component, a significant role in participants’ improvement is attributed to the psychoeducational component.

The seminar on psychoeduction was designed based on the logotherapy principles according to Viktor Frankl and delivered in a group format. The existential approach of logotherapy creates structure and meaning (24, 25), which are associated with higher quality of life, lower levels of psychological stress, greater well-being (26, 27, 28, 29, 30), and an increase in resilience (31, 32). We know from the TK’s study on stress that the causes of stress often lie in school or work and in the high demands one puts on oneself (5). These two aspects were worked through in the psychoeducational seminar in relation to the individual situation by perceiving causes, evaluating these causes, and increasing resilience.

The PSQ measures the subjective perception, evaluation, and further processing of stressors (33), thereby explaining the improvement in the IG compared to the CG-B. The TICS-SSCS measures, among other things, areas such as chronic worries, work overload, and lack of social recognition (13), which were also dealt with in the context of the series of seminars.

Similar trends were seen with regard to general well-being. Participation in a prevention program was associated with an improvement at 12 months. Here again, the improvement was greater for a program with psychoeducation compared to one without. The relationship between stress and well-being is seen as causal for this. Mental well-being is an important indicator for good health (34). Since poor health is associated with higher stress perception and vice versa (5), a positive trend in terms of stress perception also has a positive effect on well-being.

Sleep quality (PSQI) at the 12-month time point likewise improved primarily in the IG compared to baseline values and the CG-C. The prevention program did not include specific training on the subject of “sleep”, hence it is assumed that the reduction in perceived stress had an effect on sleep quality. This assumption is supported by a host of studies reporting a negative association between stress and sleep quality (35, 36). A variety of methods—often mindfulness training, but also physical activity—are already being shown to be effectively used for stress reduction (10, 37). These are often not restricted to individual measures, but are instead designed as recurring or combined interventions. The structural and personnel advantages of a stay at a health resort can be effectively incorporated particularly in multimodal preventive health programs (20, 21, 22).

Although group differences were seen in terms of sex distribution at the baseline survey, none were seen at the time of recruitment or allocation to groups. This did not show an effect on the results. Slightly more men were allocated to the CG-B through randomization, in addition to which more women dropped out. As a result of 33 dropouts even before the baseline survey, a further recruitment phase became necessary. The second randomization list could not be completely filled due to a lack of interested trial subjects, which is assumed to be responsible for the uneven distribution of male and female subjects across the three trial groups.

A further consequence of the dropouts was a higher number of randomized individuals than had been determined in the sample size estimate. However, the final number of participants corresponded to the sample size estimate.

The surveys were conducted among the same subjects at multiple time points. One must assume natural fluctuations around the true mean, with participants in the IG having slightly more favorable conditions with regard to school-leaving qualification in the baseline survey. At the same time, the mean PSQ and WHO-5 score was somewhat lower in the control groups. Particularly in trials with large differences in the outcome measures at different measurement time points, a regression effect to the mean may emerge (38). This needs to be taken into consideration when interpreting the results.

Limitations in this trial could lie in non-recorded parameters with a potential effect on the perception of stress (for example, personality traits, social support). The voluntary nature of participation in the trial may have resulted in the sample comprising highly motivated individuals. The high acceptance of group allocation should be viewed positively. The small number of dropouts prior to the start of the trial due to a lack of interest in the allocated group—only two (IG and CG-C) individuals—shows that the lack of blinding in the CG-C was unlikely to have had a negative effect on the trial. Having to take vacation days and obtain permission from employers, rather than financial reasons (the costs of the intervention were borne in the trial setting), were deemed to be the decisive factors when it came to non-participation. Subjective stress level as an inclusion criterion may reduce the generalizability of the trial results to respective groups of the population.

The evaluation of complex interventions in health promotion and prevention is rare—methodologically well-thought-through randomized controlled trials (RCT) make a significant contribution to elucidating cause-and-effect relationships here (39). Thus, one strength of the trial is its design involving the comparison of two prevention programs that differed in only one element, a survey-only group, as well as the blinding of trial participants with regard to the content of the program. Other strengths include: the use of standardized and internationally validated survey instruments, the long follow-up survey period, the high questionnaire response rate, the low proportion of missing values, and a low dropout rate following the start of the intervention.

Overall, one can assume on the basis of the trial results that a 2-week program with a 4-day refresher course after 6 months can reduce perceived stress and the chronic stress experience in adults with high levels of exposure to stress. A prevention program that is specifically oriented to “stress” as an indication and includes a psychoeducational seminar is associated with greater improvements compared to a program without a psychoeducational seminar and is able to sustain these improvements in the long term.

Summary

Only a small number of studies have investigated multimodal prevention programs for stress reduction. However, these are needed in order to ensure evidence-based decision-making regarding the use of this type of program (40). This exploratory trial describes a reduction in perceived stress following a preventive intervention that included a refresher course and a specific psychoeducational component. Further methodologically sound research is desirable for the development of a solid data basis.

Data Sharing

Due to the provisions in the data protection and consent declaration, data sharing is not possible.

Funding

The trial was financed by the Bavarian State Ministry of Health and Care as part of a funding program (grant notification No. K1–04–00078–2015-EA_BayGA). Those applying for this program—in this case the Bad Birnbach health resort administration—had to contribute a 30% share of own funds. The costs for the medical and therapeutic applications were covered by the AOK or the individual health insurance. The Chair of Public Health and Health Services Research (IBE), LMU Munich, Germany, received third-party funding to conduct this trial.

Conflict of interest statement

CJS is a speaker at the “Health Promotion and Prevention” (Gesundheitsförderung und Prävention) seminar of the Bavarian Medical Association.

The remaining authors declare that no conflict of interest exists.

Manuscript received on 05 December 2022, revised version accepted on 18 July 2023.

Translated from the original German by Christine Rye.

Corresponding author
Veronika Throner (M.Sc. Public Health)
Lehrstuhl für Public Health und Versorgungsforschung (IBE)
Ludwig-Maximilians-Universität München
Elisabeth-Winterhalter Weg 6, 81377 München, Germany

Cite this as:
Throner V, Coenen M, Schuh A, Jung-Sievers C, Kus S: A multimodal prevention program for stress reduction—results of a randomized controlled trial. Dtsch Arztebl Int 2023; 120: 721–8. DOI: 10.3238/arztebl.m2023.0179

Supplementary material

eReferences, eMethods, eTables:
www.aerzteblatt-international.de/m2023.0179

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