BACKGROUND: Stress-induced Exhaustion Disorder (ED) is associated with work absenteeism and adverse health outcomes. Currently, little is known regarding how the symptoms of ED are interrelated and whether the patterns of symptoms influence treatment outcomes. To this end, the current study applied network analyses on ED patients participating in a multimodal intervention.

METHODS: The first aim of the study was to explore the internal relationships between exhaustion symptoms and identify symptoms that were more closely related than others. A second aim was to examine whether the baseline symptom network of non-responders to treatment was more closely connected than the baseline symptom networks of responders, by comparing the sum of all absolute partial correlations in the respective groups' symptom network. This comparison was made based on the hypothesis that a more closely connected symptom network before treatment could indicate poorer treatment outcomes. Network models were constructed based on self-rated ED symptoms in a large sample of patients (n = 915) participating in a 24-week multimodal treatment program with a 12-month follow-up.

RESULTS: The internal relations between self-rated exhaustion symptoms were stable over time despite markedly decreased symptom levels throughout participation in treatment. Symptoms of limited mental stamina and negative emotional reactions to demands were consistently found to be the most closely related to other ED symptoms. Meanwhile, sleep quality and irritability were weakly related to other exhaustion symptoms. The symptom network for the full sample became significantly more closely connected from baseline to the end of treatment and 12-month follow-up. The symptom network of non-responders to treatment was not found to be more closely connected than the symptom network of responders at baseline.

CONCLUSIONS: The results of the current study suggest symptoms of limited mental stamina and negative emotional reactions to demands are central ED symptoms throughout treatment, while symptoms of irritability and sleep quality seem to have a weak relation to other symptoms of ED. The implications of these findings are discussed in relation to the conceptualization, assessment, and treatment of ED.

TRIAL REGISTRATION: The clinical trial was registered on Clinicaltrials.gov 2017-12-02 (Identifier: NCT03360136).

BACKGROUND: Symptom reduction occurring early in depression treatment is associated with favourable post-treatment outcome, but it is not known how early reduction in specific depression symptoms affect treatment outcome. We aimed to determine the impact of symptom-specific change from pre-treatment to week four during internet-delivered CBT (ICBT) on overall and symptom-specific depression severity at post-treatment. We hypothesized that change in mood and emotional involvement would be most strongly associated with later overall depression severity.

METHODS: 1300 participants with Major Depressive Disorder were followed over 12 weeks of ICBT using the self-report Montgomery-Åsberg Depression Rating Scale gauging nine symptoms. Linear models, informed by causal inference and cross-lagged network analysis methods, were used to estimate associations between early symptom-specific change and post-treatment depression severity, controlling for register-based and self-reported pre-treatment confounders.

RESULTS: Early reduction in all symptoms was associated with lower overall and symptom-specific depression severity post-ICBT. Seven symptoms showed similar associations between early change and overall depression severity post-treatment: mood (standardized beta [β] = 0.44), feelings of unease (β = 0.39), ability to concentrate (β = 0.46), initiative (β = 0.43), emotional involvement (β = 0.42), pessimism (β = 0.44), and zest for life (β = 0.42). Change in sleep (β = 0.27) and appetite (β = 0.27) had weaker associations with overall depression severity at post-treatment and were the only symptoms showing the hypothesized difference compared with mood and emotional involvement.

CONCLUSIONS: The impact of early symptom-specific reduction on post-treatment depression severity in ICBT for MDD may be similar across most symptoms, but less for the sleep and appetite symptoms, although causal interpretations rests on several assumptions.

BACKGROUND AND AIMS: There has been much concern regarding potential harmful effects of video game-play in the past 40 years, but limited progress in understanding its causal role. This paper discusses the basic requirements for identifying causal effects of video game-play and argues that most research to date has focused upon ambiguous causal questions.

METHODS: Video games and mental health are discussed from the perspective of causal inference with compound exposures; that is, exposures with multiple relevant variants that affect outcomes in different ways.

RESULTS: Not only does exposure to video games encompass multiple different factors, but also not playing video games is equally ambiguous. Estimating causal effects of a compound exposure introduces the additional challenge of exposure-version confounding.

CONCLUSIONS: Without a comparison of well-defined interventions, research investigating the effects of video game-play will be difficult to translate into actionable health interventions. Interventions that target games should be compared with other interventions aimed at improving the same outcomes.

Our understanding of the underlying psychological processes of development, maintenance, and treatments for stress-induced exhaustion disorder (ED) remains limited. Therefore, the current study aimed to explore whether sleep concerns, pathological worry, perfectionistic concerns, and psychological flexibility mediate change in exhaustion symptoms during a Multimodal intervention for ED based on Cognitive behavioral therapy principles. Participants (N = 913) were assessed at three time points, and mediation was explored using a two-criteria analytical model with linear mixed-effects models (criterion one) and random intercepts cross-lagged panel modeling (criterion 2). Criterion one for mediation was successfully met, as the findings indicated significant associations between time in treatment, with all suggested mediators, and exhaustion symptoms (significant ab-products). However, criterion two was not satisfied as changes in the mediators did not precede changes in exhaustion symptoms. Therefore, mediation could not be established. Instead, changes in the suggested mediators appeared to result from changes in exhaustion symptoms. Consequently, sleep concerns, pathological worry, perfectionistic concerns, and psychological flexibility appear to improve in conjunction with exhaustion symptoms during treatment, where improvement in exhaustion is indicated as the main driving factor, based on this exploratory analysis. The implications of these findings are contextualized within a broader framework of process-based therapy.

Social exposures and their impact on mental health has proven hard to capture, partly owing to the complex and multifaceted nature of social reality. Sexual harassment and sexual violence (SHV) are no exceptions. SHV can be conceptualized as a continuum of negative sexual experiences whose severity vary depending on multiple determinants. Further, SHV can be conceptualized as either discrete events or as a generally hostile sexual environment represented by latent variables. With any of these conceptualizations, SHV constitutes a broad construct containing many kinds of negative experiences. This ambiguity poses challenges for determining the mental health consequences, as different forms of SHV may vary in terms of their mental health impact. We discuss different conceptualizations of SHV in relation to mental health outcomes through the lens of the potential outcomes framework, with a focus on the consistency condition. The multiple versions of treatment theory is presented to show how to provide formal interpretations of causal estimates under ambiguous exposures. Lastly, we provide suggestions on how the increase the clarity and interpretability of the effects of SHV on mental health, by increasing the precision of the causal questions and the use of more specific definitions of SHV.

Purpose: To determine the gender-specific impact of recent exposure to different forms of sexual harassment and sexual violence (SHV) on depression and anxiety symptoms three, six, and nine months later.

Methods: We recruited 2229 women and 1274 men studying at Swedish universities and followed them with web-surveys every three months over one year. We estimated mean differences (MDs) of depression and anxiety symptoms between exposed and unexposed at each follow-up, adjusting for prior SHV, prior depression and anxiety symptoms and potential confounders.

Results: For women, sexual harassment (wide subjective definition) was associated with higher symptom levels of depression (MD 1.0 [95% CI: 0.3; 1.7]) and anxiety (MD 0.8 [95% CI: 0.3; 1.4]) three months later. Unwanted sexual attention was associated with higher symptom levels of anxiety three (MD 0.5 [95% CI: 0.1; 0.8]) and six months later (MD 0.4 [95% CI: 0.0; 0.7]). Exposure to sex against ones will was associated with higher depression symptoms three (MD 1.7 [95% CI: 0.1;3.4]), and six months later (MD 3.1 [95% CI: 1.0; 5.2]). Trends indicated that associations with subsequent mental health differed between forms of SHV among women, and that most associations were more pronounced in temporal proximity to the exposures. For men, we refrain from interpreting the results since they showed high variability and were not robust to sensitivity analyses using multiple imputation to account for missing outcome data.

Conclusions: Among women, several forms of SHV were associated with higher subsequent depression and anxiety symptoms.

BACKGROUND: Procrastination is common among university students and associated with adverse outcomes such as physical and mental health problems. According to the Temporal motivation theory procrastination may vary over time depending on the temporal proximity to goals and deadlines.

AIMS: To determine if mean procrastination levels among university students varies over an academic year, and if trajectories of procrastination are moderated by gender identity, perfectionistic strivings, and/or perfectionistic concerns.

SAMPLE: Swedish university students (n = 1410).

METHODS: The cohort was followed with web-surveys at four time-points over one academic year (Late semester, Mid semester, After semester, and Early semester). Generalized Estimating Equations were used to estimate mean levels of self-rated procrastination at the different time-points.

RESULTS: We found only small fluctuations in mean procrastination levels over the academic year. Participants with high perfectionistic concerns demonstrated higher mean procrastination levels at all time-points, but neither gender identity, perfectionistic concerns nor perfectionistic strivings affected the slope of the mean procrastination trajectories.

CONCLUSIONS: In this cohort of Swedish university students, self-rated procrastination levels were stable over the academic year. Perfectionistic concerns, but not gender identity or perfectionistic strivings, was associated with higher levels of procrastination.

Perfectionism can be problematic when your self-worth is dependent on achievements and leads to inflexible standards, cognitive biases, and rigid behaviors. Cognitive behavior therapy for perfectionism is shown to be effective, including for targeting psychiatric symptoms and when delivered via the Internet (iCBT-P). However, few studies have compared it to an active comparator. The current study randomly assigned 138 participants seeking help for perfectionism to iCBT-P or Internet-based Unified Protocol (iUP). Both treatments provided guidance on demand from a therapist and were eight weeks in duration. The results indicated large within-group effects of Cohen's d 2.03 (iCBT) and 2.51 (iUP) on the Clinical Perfectionism Questionnaire at post-treatment, and maintained effects at 6- and 12-month follow-up, but no between-group difference (β = 0.02, SE = 1.04, p = .98). Secondary outcomes of depression, anxiety, quality of life, self-compassion, procrastination, and stress ranged from small to large, with no differences between the conditions. Both treatments were deemed credible, relevant, of high quality, and well-adhered by the participants. Further research needs to be conducted, but the findings could indicate a lack of specificity, perhaps suggesting there is no need to differentiate between different treatments that are transdiagnostic in nature.

Mental disorders are among the leading causes of years lost due to disability in young people globally. Students are no exception, both mental disorders and mental health problems are common among university students with dramatic increases reported in recent years. The aetiology of mental disorders and mental health problems is generally assumed to be multicausal, with factors at different levels contributing to their development. Given the complexity of the causal network underlying mental health problems, it has been argued that a clear causal framework is needed when studying the aetiology of mental health problems. This thesis aimed to investigate some aspects of the potential aetiology of mental health problems among university students. Specifically, it focuses on four exposures at the psychosocial level presented in four studies: 1) the coronavirus disease (COVID-19) pandemic, 2) poor sleep quality, 3) procrastination and 4) sexual harassment and sexual violence. In addition to the discussion provided in each respective paper, this thesis discusses limitations and possible interpretations of our results from a modern causal inference perspective.

The four studies of this thesis are based on The Sustainable University Life (SUN) cohort. The SUN cohort followed 4262 university students from eight universities in and around Stockholm, Sweden, with web-surveys at five time-points over one year.

In Study I, we aimed to determine the mean trajectories of depression, anxiety, and stress symptoms among university students in Stockholm before and during the first months of the COVID-19 pandemic. For this, we included a subsample of 1836 university students that entered the SUN cohort before the outbreak of the COVID-19 pandemic, and were followed during the months before the pandemic, during the first wave of the pandemic and in the summer, months following the first wave of the pandemic. We found that mean depression, anxiety, and stress symptom levels were largely stable during the first wave compared to the months before the pandemic and decreased slightly during the following summer months. Our results indicate that mean levels of mental health symptoms did not change much during the early phase of the pandemic compared to before the pandemic.

In Study II, we aimed to determine whether sleep quality statistically interacts cross-sectionally with loneliness, risky alcohol use, perfectionistic concerns and/or physical inactivity in relation to depressive symptoms in university students. We conducted a cross-sectional study using baseline-data from all 4262 participants in the SUN cohort. We found that while all factors were associated with depressive symptoms, only perfectionistic concerns interacted with sleep quality in its relation to depression. This interaction was quite weak and explainedonly a small proportion of the variance in depressive symptoms. Overall, we did not find support for our hypothesis that poor sleep quality could interact with several different potential risk factors for depressive symptoms.

In Study III, we aimed to evaluate the associations between procrastination and sixteen subsequent health outcomes (including mental health symptoms, disabling pain, lifestyle behaviours and psychosocial health factors), measured 9 months later, among university students. We used data from all participants responding to the first follow-up in the SUN cohort (n=3525) and found that procrastination was related to several subsequent health outcomes, including symptoms of depression, anxiety and stress, while controlling for multiple potential confounders. Although we cannot rule out non-causal explanations for these associations, the results indicate that procrastination could have an effect on health outcomes among students, but that it is likely to be rather small for any specific health outcome.

In Study IV, we investigated the impact of recent exposure to different forms of sexual harassment and sexual violence; 1) unwanted sexual attention, 2) offensive sexual remarks, 3) presentation or distribution of sexist material, 4) uncomfortable touching, 5) being offered benefits for sex and 6) sex against ones will, along with a wide definition of sexual harassment: sexual harassment (wide subjective definition) on levels of depression and anxiety symptoms three, six and nine months later, for women and men, respectively. We conducted a cohort study using data from all women and men responding to the first follow-up in the SUNcohort (n= 3503). Our results showed that women recently exposed to 1) sexual harassment (wide definition), 2) unwanted sexual attention and 3) sex against ones will showed higher subsequent levels of depression and/or anxiety symptoms. The general trend was that all exposures were related to higher symptom levels at three months, but that this difference between exposed and unexposed diminished over time, although these trends are uncertain with wide confidence intervals. The exception was exposure to sex against ones will, where exposed showed elevated symptom levels throughout the follow-up period. For men, the estimates were uncertain overall, and we refrain from interpreting these results. Our results indicate that recent exposure to different forms of sexual harassment and sexual violence may impact later depression and anxiety symptoms among women, and that there could be differences in the strength and long-term impact on mental health between different forms of sexual harassment and sexual violence. Again, we cannot, with certainty rule out non-causal reasons for these associations.

Interpreting any of these results as causal effects rests on multiple assumptions, which are discussed in the thesis. Determination of causal effects preferably relies on triangulation of results from different studies with different methodology. Overall, however, I believe that this thesis has strengthened the evidence that procrastination and sexual harassment and sexual violence may be causes of mental health problems among university students. An equally important finding, is that mental health seemed rather stable during COVID-19 pandemic, indicating that the pandemic may not have caused increased mental health problems on the group level.

BACKGROUND: The incidence of sick leave due to stress-related disorders such as exhaustion disorder (ED) is high in many economically developed countries. Meanwhile, knowledge about facilitating return to work during clinical interventions for ED patients is still limited. The current study aimed to investigate if improvements in exhaustion symptoms, insomnia, perfectionistic behaviors, psychological flexibility, and perceived work ability during treatment of ED were associated with subsequent sick leave in the year following treatment.

METHODS: Using a cohort of 880 ED patients who had participated in a multimodal intervention based on Cognitive Behavior Therapy, we estimated the association between one standard deviation (SD) improvement in treatment-related variables and the rate of net days of sick leave one-year following treatment.

RESULTS: Our results showed that improvements in all treatment-related variables were associated with lower sick leave rates one year following treatment. Improvements in exhaustion symptoms (rate ratio (RR): 0.70 [95% CI 0.66; 0.75]) and self-perceived work ability (RR 0.56 [95% CI 0.50; 0.63]) showed the strongest associations to subsequent sick leave.

CONCLUSIONS: These findings suggest that interventions focusing on exhaustion symptoms, insomnia, perfectionistic behaviors, psychological flexibility, and perceived work ability can have a meaningful impact on ED patients' subsequent sick leave.

TRIAL REGISTRATION: Clinicaltrials.gov (Identifier: NCT03360136).