Background. The prevalence of metabolic syndrome is high in patients with depression or anxiety, which might explain the higher risk of cardiovascular mortality in this population. Symptoms of...Show moreBackground. The prevalence of metabolic syndrome is high in patients with depression or anxiety, which might explain the higher risk of cardiovascular mortality in this population. Symptoms of affective disorders can lead to changes in eating behaviors. However, poor diet quality seems implicated in underlying pathology of behavioral health disorders and could be a risk factor for developing depression and anxiety disorders. Objective. We aim to investigate the association between diet quality and metabolic syndrome in participants with and without anxiety and depressive disorders. Psychotropic medication, symptom severity, and lifestyle factors (i.e. physical activity, smoking, and alcohol use) are investigated as potential moderators. Methods. In the Netherlands Study of Depression and Anxiety (NESDA), the Mediterranean diet, the metabolic syndrome, physical activity, smoking, alcohol use, severity of symptoms, and medication were assessed among participants with depressive (n = 110), anxiety (n = 149), remitted disorders (n = 761), comorbid disorders (n = 110), and healthy controls (n = 295), in a cross-sectional design. Follow-up data from NESDA wave six is used, nine years after baseline measurement. Results. Participants (n = 1425) were on average 52.4 years old (SD = 13.13) of which 65.2% female. The association between diet quality and metabolic syndrome was the strongest for individuals with current depression (β = -.23 (CI: -.42 ; -.08); t = -2.87; p = .005), comorbid disorders (β = -.20 (CI: -.36 ; -.02); t = -2.22; p = .029), and remitted disorders (β = -.12 (CI: -.19 ; -.06); t = -3.85; p < .001). The association between diet quality and metabolic syndrome was not moderated by medication, symptom severity and lifestyle factors. Limitations. Results cannot be generalized to other cultures and the use of self-report scales could lead to a misclassification bias. Due to the cross-sectional design, it is impossible to provide evidence for temporal or causal relations. Conclusion. Low adherence to the Mediterranean diet is associated with a high score on metabolic syndrome for patients experiencing depression, comorbid depression and anxiety or remitted depression or anxiety. This association is not moderated by medication, symptom severity and lifestyle factors.Show less
Objective: Several studies have examined mechanism of change within psychotherapy. However, mechanism of change research on depression is scarce. Due to the cognitive features crucial to depression...Show moreObjective: Several studies have examined mechanism of change within psychotherapy. However, mechanism of change research on depression is scarce. Due to the cognitive features crucial to depression, CBT is the most promising treatment approach, yet it still leaves room for improvement. This thesis aims to identify between-patient and within-patient effects of anhedonia, a critical diagnostic criterion in depression associated with psychotherapeutic outcomes. Method: A sample of 139 patients with MDD undergoing outpatient CBT interventions completed the Well-being Index 5 (as a proxy for depression severity), and a single-item measure of anhedonia session-by-session. Data was analyzed employing hierarchical linear models. Results: Hybrid random effect models revealed significant between- and within-patient effects of anhedonia on therapeutic outcomes. Overall levels of anhedonia across sessions, as well as variations in anhedonia session-by-session, were associated with depression severity. Higher average anhedonia was associated with poorer outcomes, and a reduction in anhedonia session-by-sessions was associated with decreased depression severity. The cross-level interaction demonstrated that both between- and within-patient effects were significantly related to the well-being outcome measurement. Conclusion: Results align with previous research on addressing anhedonia more directly within psychotherapy. These results emphasize that trying to reduce anhedonia could be a relevant path for change in depression treatment. Keywords: cognitive-behavioral therapy, anhedonia in depression, mechanisms of change, hybrid random effects modelShow less
Depression is mental disorder characterized by impaired overall functioning as well as diminished cognitive performance. Its cause is associated with an imbalance of neurotransmitter functioning in...Show moreDepression is mental disorder characterized by impaired overall functioning as well as diminished cognitive performance. Its cause is associated with an imbalance of neurotransmitter functioning in affected individuals. Recent studies have demonstrated the ability of L-tyrosine, a natural amino-acid and precursor of the neurotransmitter dopamine, to increase dopamine levels within the brain and subsequently benefit different cognitive functions. Additionally, another field of research has repeatedly shown that exposure to novel stimuli can enhance memory performance in both animals and humans. In our study we investigated whether the intake of tyrosine (administered in a double-blind, betweensubjects design) enhances recall and recognition performance following the exposure to an either novel or familiar virtual reality environment (within-subjects design) in healthy participants. We expected tyrosine and the novelty exposure to result in improved cognitive performance. Furthermore, we hypothesized tyrosine to even out the assumed negative impact of increasing severity of depressive symptoms on the recall and recognition scores. Our sample consisted of 30 individuals aged 18 to 30. The study involved a total of five sessions including three laboratory and two online sessions. The first session included the familiarization to the VR environment as well as the assessment of current depressive symptoms with the patient health questionnaire. The other two laboratory sessions entailed the treatment administration, VR environment exploration as well as immediate memory assessments, while the online sessions consisted of delayed memory assessments. To examine the effects of treatment, novelty, and depressive symptoms on memory performance, our data was analysed with repeated measures analyses of variance. Contrary to our expectations we did not find significant effects of novelty or the tyrosine supplement on recall or recognition scores. While heightened symptoms of depression negatively impacted the cognitive performance in our sample, tyrosine did not have a mitigating effect on the different severity of symptoms. Future research is advised to explore methodological adjustments by making use of more immersive VR methods, alternative dosages of tyrosine, and include clinical samples to better understand these factors' potential impact on memory.Show less
Literature in the field of personality research has found personality traits to be key when it comes to understanding mental illness (Schomerus et al, 2013). Introversion specifically has been...Show moreLiterature in the field of personality research has found personality traits to be key when it comes to understanding mental illness (Schomerus et al, 2013). Introversion specifically has been found to be associated with several mental illnesses (Janowsky et al, 2001; Kotov et al, 2013). For this reason, it was investigated to what extent introversion is correlated with depression, as it is a highly prevalent disorder with major consequences to the wellbeing of those who suffer it (Trivedi, 2020). More specifically, the research questions is: “To what extent is personality trait introversion associated with depression?”. Based on studies such as the ones shown previously, the hypothesis was that introversion would be positively correlated with depression. For these purposes, European Social Survey data was used, as it provides a huge sample and utilises questions similar to those found in a clinical setting such as Beck’s Depression Inventory (Beck , Steer & Garbin, 1988). Logistic regression was utilised when performing the analysis, and several models were created and compared. Confounding variables like gender, income and highest achieved education level were taken into account. The results showed that introversion was correlated with depression, in line with the initial hypothesis. However, only one of the two components that make up introversion was correlated with it. One of the biggest implications of this finding is that studies in the future should look into how the components of each personality trait are associated with any given mental illness, rather than traits as a whole. Future research is needed to explore in further detail how introversion is correlated with depression.Show less
Background: The present study aimed to examine the interconnections between chronotype, sleep quality, alcohol consumption and mental health, and the role of sex (male and female) on these...Show moreBackground: The present study aimed to examine the interconnections between chronotype, sleep quality, alcohol consumption and mental health, and the role of sex (male and female) on these connections. Previous studies have shown that evening chronotype is connected to poorer sleep quality, higher alcohol consumption and worse mental health. Yet, there is limited research on the interactions between all these variables and on the role of sex differences. The current study hypothesized the mediating role of alcohol between sleep and mental health, and the moderating role of sex and mental health. Methods: Quantitative data of a big participant sample (N=2165) from the Netherlands Study of Depression and Anxiety (NESDA) was used. Participants derived from various settings and represented both healthy and clinical groups. Self-report measures were used, and mediation and moderation analyses were performed to test the hypotheses. Results: Alcohol was not found to mediate the relationship between sleep and mental health. Sex differences were found in anxiety and alcohol consumption, with women scoring higher in both. Sex also acted as a moderator between sleep quality and depression, and sleep quality and anxiety. Mental health status was found to affect chronotype and sleep quality, with healthy individuals being morning chronotypes more frequently and reporting higher sleep quality. Conclusions: The results of the current study contribute to our understanding of the interactions between sleep, alcohol and mental health, underlining the role of sex and mental health. This knowledge can be used in designing more personalized and multidimensional treatments, improving the quality of psychological care.Show less
Background: Many patients with Major Depressive Disorder (MDD) suffer from self-stigma. Self-stigma can lead to a decrease in recovery speed and treatment adherence. Psychoeducation for depression...Show moreBackground: Many patients with Major Depressive Disorder (MDD) suffer from self-stigma. Self-stigma can lead to a decrease in recovery speed and treatment adherence. Psychoeducation for depression has shown to be effective in improving treatment adherence and self-stigma. In recent years, researchers investigated Virtual reality (VR) as a potential tool in the treatment of depression. Studies have shown that VR interventions can reduce, among other things, self-stigma and depressive symptoms. We investigated the impact of a VR experience combined with psychoeducation compared to traditional, non-VR psychoeducation on self-stigma and depressive symptoms in individuals with MDD. We expected the VR intervention to have a more positive effect in reducing self-stigma and depressive symptoms than non-VR. Methods: The 31 recruited participants, aged 18-65 years old, were randomized into two groups: VR and non-VR. Two 360-degree VR videos were developed to experience a day in the life of a patient with depression. Self-stigma and depressive symptoms were measured before intervention (T0), directly after intervention (T1, only self-stigma), after 1 week (T2), and a follow-up after 10 weeks (T3). A repeated measures ANOVA was used for comparing the treatment groups. Results: Contrary to the hypothesis, the repeated measures ANOVA results indicated no significant interaction effect between time and treatment group for self-stigma (p = .393). In terms of depressive symptoms, a repeated measures ANOVA revealed a significant interaction effect between time and treatment group (p = .027), with a medium effect size (η2 = .095). Post hoc testing using Bonferroni showed that non-VR significantly decreased depressive symptoms across different time points compared to VR. Additionally, post hoc testing revealed that self-stigma and depressive symptoms may be positively correlated. Conclusion: No significant difference was found between the two treatment conditions in terms of decreasing self-stigma. However, the non-VR condition demonstrated a significant decrease in depressive symptoms compared to the VR condition. Additionally, positive correlations were observed between self-stigma and depressive symptoms, which emphasize the value of incorporating psychoeducation into treatment plans for people with MDD.Show less
Objective: Multiple Sclerosis (MS) is a chronic neurological disorder characterized by a wide range of symptoms, of which physical and cognitive impairments are prominent. Cognitive functioning in...Show moreObjective: Multiple Sclerosis (MS) is a chronic neurological disorder characterized by a wide range of symptoms, of which physical and cognitive impairments are prominent. Cognitive functioning in MS has received increasing attention due to its significant impact on quality of life. However, the exact relationship between physical functioning and cognitive functioning in people with MS (PwMS) remains insufficiently understood. This study aimed to explore the predictive value of physical outcome measures on cognitive functioning. Furthermore, the influence of disease severity and anxiety and depression on the relationship between physical outcome measures and cognitive functioning is explored. Methods: Conducted as part of the ‘Don’t be late!’ project, this study included 23 PwMS (Mean age = 46.63, SD = 11.13; 60.9 % female). Physical functioning was assessed using balance, walking speed, grip strength, dexterity and endurance. Furthermore, cognitive functioning was assessed using the Minimal Assessment of Cognitive Functions in MS and disease severity and anxiety and depression were measured using the Expanded Disability Status Scale and the Hospital Anxiety and Depression Scale, respectively. Multiple regression analyses were performed to determine the predictive value of physical functioning on cognitive functioning. Mediation analyses were performed with disease severity and anxiety and depression as mediating factors. Results: No significant model for the predictive value of physical outcome measures on cognitive functioning was found (p = .117). Furthermore, the study found no significant mediating effects of disease severity (p = .979) or anxiety and depression (p = .633) on this relationship. Due to missing values on the Paced Auditory Serial Addition Test (PASAT), a post-hoc analysis was conducted. Significant effects were found for the predictive value of balance (p = .016), dexterity (p = .045) and walking speed (p = .008) on cognitive functioning. Conclusion: The study identified significant links between balance, dexterity, walking speed, and cognitive functioning in PwMS. It faced limitations including a small sample size and its cross-sectional nature. Despite these limitations, this study suggests that the interplay between physical and cognitive domains in MS is multifaceted and warrants more nuance investigation.Show less
Background. Endometriosis is a debilitating gynecological disorder, oftentimes accompanied by chronic pelvic pain (CPP) and mental health conditions such as depression. Previous research has...Show moreBackground. Endometriosis is a debilitating gynecological disorder, oftentimes accompanied by chronic pelvic pain (CPP) and mental health conditions such as depression. Previous research has established that CPP, which is unrelated to the occurrence of menstruation, is highly predictive of depression scores in females with endometriosis. In the context of patients with chronic illnesses, pain acceptance has been highlighted as playing a crucial role in psychological outcomes such as depression. Pain acceptance is determined by the extent to which a life-focus, or a pain-focus is maintained. The main objective of the study was to determine the interplay between CPP, pain acceptance and depression in participants diagnosed with endometriosis. Methods. The study had a retrospective, cross-sectional research design, using convenience sampling to recruit respondents. A final 232 respondents completed the survey, composed of an ad-hoc item to measure CPP (Numeric Rating Scale, NRS) and validated questionnaires to examine pain acceptance (Chronic Pain Acceptance Questionnaire – 8, CPAQ-8) and depression (Patient Health Questionnaire – 9, PHQ-9). A correlation between CPP and depression was conducted, and the mediatory effect of pain acceptance in this relationship was investigated. Results. Initially, a significant and positive, however weak correlation between CPP and depression was found. Subsequently, pain acceptance was determined as a significant mediator in the relationship between CPP and depression. Discussion. In comparison with previous research in the general population, the PHQ-9 scores were higher and CPAQ-8 scores were lower in this study, indicating more severe depression, and lower pain acceptance scores. The mediation model established that experiencing CPP negatively impacts pain acceptance, which negatively impacts depression in females with endometriosis. Further research on mental health vulnerabilities in females with endometriosis, and an increase in social awareness and professional support is required.Show less
The birth-control pill is a widely used form of contraception among young women. However, using oral contraception (OC) comes with a number of reported side effects, one being significant mood...Show moreThe birth-control pill is a widely used form of contraception among young women. However, using oral contraception (OC) comes with a number of reported side effects, one being significant mood deterioration and depressive symptoms. Research is divided concerning the question of whether such a relationship between OC and depressive symptoms actually exists and points to contradictory research results when investigating said relationship. One explanation for these differing study results is the existence of a moderator. It has been suggested that personality might act as such a moderator. The present study aims to investigate further whether personality indeed moderates the relationship between OC and depressive symptoms. Personality was split into the Big-Five personality factors Neuroticism, Openness, Conscientiousness, Extraversion, and Agreeableness. Participants were 515 females aged 18-29 and were divided into two groups. One that stated to take OC and one that only uses physical contraception. They received the Big-Five Inventory-10 (BFI-10) and the Patient Health Questionnaire-9 (PHQ-9) to assess their personality and their depressive symptomatology, respectively. Results showed no relation between OC and depressive symptoms and no moderation effect of any personality factor on said relationship. Therefore, the present study shows no signs of personality influencing the relationship between OC and depressive symptoms. However, it has been found that Neuroticism and Conscientiousness were both significantly related to depressive symptoms. Limitations, study implications, and directions for future research are discussed.Show less
Research master thesis | Psychology (research) (MSc)
closed access
Observing emotions in others’ facial expressions is an important factor guiding social interaction. Observing others’ emotions elicits physiological arousal in the observer, which is reflected in...Show moreObserving emotions in others’ facial expressions is an important factor guiding social interaction. Observing others’ emotions elicits physiological arousal in the observer, which is reflected in increased pupil diameter (i.e., pupil dilation). The current study used pupil dilation as an index of physiological arousal to explore children’s responses to emotional facial expressions. More specifically, we investigated whether maternal symptoms of depression and/or anxiety were related to offspring’s pupil responses to negative (versus positive) facial displays irrespective of the child’s symptomology. A community sample of 87 mother- (M = 42.30, SD = 5.60, range = 27-57) child (M = 10.11, SD = 1.32, range = 7.2-12.9) dyads participated in the current study. Mothers and offspring reported on their depressive and anxiety symptoms via self-report questionnaires. Children’s pupil responses to angry, fearful, sad, and happy dynamic facial displays were measured during the dynamic emotions task using eye-tracking. Results revealed that maternal depressive symptoms were not related to child pupil responses to negative (versus positive) faces. Higher levels of maternal anxiety, however, were linked to stronger child pupil responses to fearful and sad faces than to happy faces. In turn, child pupil responses to angry (versus happy) faces did not statistically differ as a function of maternal anxiety. These findings persisted after accounting for the link between child anxiety symptoms and child pupil responses. Therefore, the way typically developing children react to negative versus positive emotional faces in later childhood appears to be related to maternal levels of anxiety, but not to maternal levels of depression. This points to the importance of exploring maternal anxiety symptoms as a potential risk factor for the development of negativity biases in offspring across the general population.Show less
Background: Recent evidence indicates that the gut-brain axis plays a role in mental well-being, with microbiota as a crucial component. Yet, it is still unclear how it influences cognitive...Show moreBackground: Recent evidence indicates that the gut-brain axis plays a role in mental well-being, with microbiota as a crucial component. Yet, it is still unclear how it influences cognitive reactivity, known as a predictor of depression. Understanding how the microbiota-gut-brain axis affects cognitive reactivity may contribute to enhancing interventions targeting cognitive reactivity and eventually depression. Objective: The current observational study investigated the association between cognitive reactivity and Alpha diversity in the gut microbiota, and the moderating role of enterotype among (self-reported) healthy Dutch adults (N = 75, M age = 24.04, SD = 3.43). Methods: The gut microbial composition and enterotype were based on a 16S rRNA analysis, after which the Shannon index was calculated to indicate Alpha diversity. Based on literature, enterotype was categorized into three groups: Bacteroides, Prevotella, and Ruminococcus. The LEIDS-r was used to measure cognitive reactivity. A simple linear regression and moderation analysis using Hayes PROCESS were performed. Results: The moderation analysis revealed a significant moderation effect; however, the overall model was not significant therefore the results should be interpreted carefully. The results demonstrated an association between gut microbiome diversity (Shannon index) and cognitive reactivity among participants in the Bacteroides dominant group and the Ruminococcus dominant group, whereas no such correlation was found among participants in the Prevotella dominant group. Discussion: The current findings suggest an enterotype-dependent link between gut microbiota diversity and cognitive reactivity in healthy adults, which may provide a new perspective for the development and deployment of therapeutic gut microbial interventions targeting cognitive reactivity and ultimately depressionShow less
Depression is one of the most common health problems among the student population and as such, it is crucial to understand and identify the factors that contribute to its onset and persistence. The...Show moreDepression is one of the most common health problems among the student population and as such, it is crucial to understand and identify the factors that contribute to its onset and persistence. The network approach to psychopathology conceptualizes mental health disorders as complex systems of interrelated factors. This approach facilitates the identification of key risk factors associated with the onset and maintenance of depression. The aim of the current study was to examine the relationship between multiple risk factors for depression and their interrelations using a network approach. A sample of 444 Dutch higher education students were assessed with multiple scales measuring several risk factors previously associated with depression. The associations between these risk factors and depression were then estimated in a regularized Gaussian Graphical Model (GGM). A total of eleven nodes were included in the network, and centrality measures and the stability and accuracy of the network were studied. Specific nodes that occupied critical positions in the network were identified, with current stress, depression, repetitive negative thinking and pessimism being the most central nodes. Depression showed the highest positive associations with current stress and sleep problems. These explorative findings offer guidance on the relative importance of certain risk factors, such as current stress, repetitive negative thinking, and pessimism over other risk factors in the network. These results could possibly have important implications for the future study and prevention of depression in higher education students. Longitudinal studies are needed to expand on these preliminary findings.Show less
Research master thesis | Psychology (research) (MSc)
open access
Ecological momentary assessment (EMA) is a data collection method in which participants’ current behaviors and experiences are sampled repeatedly in their natural environment. EMA has advantages...Show moreEcological momentary assessment (EMA) is a data collection method in which participants’ current behaviors and experiences are sampled repeatedly in their natural environment. EMA has advantages over retrospective research methods, in that it reduces retrospective bias, increases ecological validity, and offers the possibility to observe dynamical changes of variables. However, EMA protocols are burdensome for participants and may interfere with their daily activities. This can lead to non-compliance over the course of a study. Missing data can subsequently decrease statistical power, and even induce bias. This paper explored whether missing data can be predicted by various variables related to students’ primary motivation to participate, mental health, stress levels, and demographics. We analyzed data of the first cohort (N = 418) of the ongoing WARN- D project on student mental health. Participants completed a comprehensive baseline survey and took part in an 85-day long EMA study. We predicted overall rates of non- compliance by participant characteristics at baseline (Analysis 1) and weekly rates of non- compliance by time-varying factors during the EMA stage (Analysis 2). Analysis 1 showed that overall non-compliance can be predicted by baseline measures such as age, depression, substance use, and primary motivation to participate. Analysis 2 showed that weekly assessed time-varying measures like time into study, enjoyment of the study, weekly stress, anxiety, and depression may predict weekly rates of non-compliance. Participant’s sex and smartphone operating system were not related to overall non-compliance. Summarizing, non-compliance rates of participants can be predicted by participant characteristics at baseline as well as by time-varying predictors. Our findings may inform future research on potential mechanisms behind noncompliance in EMA designs that should be considered to maximize participation rates while avoiding biased conclusions.Show less
Non-verbal communication is an import social skill we humans have mastered. The eyes of others are of particular interest to us. Gaze direction in combination with the emotional expression on...Show moreNon-verbal communication is an import social skill we humans have mastered. The eyes of others are of particular interest to us. Gaze direction in combination with the emotional expression on someone’s face, provides a plethora of information about location and evaluation. Theory of mind is important in understanding this information. There is evidence that depression can cause a bias towards negative stimuli, however not all studies regarding this subject find similar results. To investigate whether depression influences attention in a negative matter a gaze cueing paradigm was used. The level of depression was measured using the BDI. Our findings indicated an effect of cue validity, but not of emotion. The level of depression did not influence attention.Show less
The literature on risk and protective factors for depression focuses on biological, demographic, social-environmental, and psychological factors. Estimating a network model, this thesis project...Show moreThe literature on risk and protective factors for depression focuses on biological, demographic, social-environmental, and psychological factors. Estimating a network model, this thesis project explores how dynamic psychological risk and protective factors for depression interact and determines which factors are more central to a network of these factors (Research Question 1). It also tests if dynamic risk and protective coping factors relate to current depressive symptoms, as prior studies suggest (Research Question 2). Cross-sectional data from 453 students at a Dutch higher education participating in the WARN-D research project were analyzed. Overall, protective factors clustered together, as risk factors did. The strongest positive associations emerged between Seeking Distraction and Ignoring and between Locus of Control and Optimism. The strongest negative relations merged between Seeking Social Support and Ignoring, Resilience and Intolerance of Uncertainty, and Catastrophizing. Self-efficacy, Resilience, and Self-esteem were the most central features of the network. The results did not support the hypothesis that all the included risk and protective factors are related to current depressive symptoms. Only some were, with the strongest positive associations being between current depressive symptoms and Persistent Thinking and Optimism. Despite the limitations of the present work, these findings highlight the importance of further research on risk and protective factors for depression.Show less
Background: Previous studies have shown that parental bonding (PB) is directly and in interaction with stressful events linked to mental health outcomes. Sexism affects many young women and is...Show moreBackground: Previous studies have shown that parental bonding (PB) is directly and in interaction with stressful events linked to mental health outcomes. Sexism affects many young women and is often associated with psychopathology. This research aimed to further investigate the relation between PB, sexual discrimination and mental health outcomes. Non-optimal maternal and paternal bonding styles and higher frequency of sexual discrimination were expected to be related to greater depressive and anxiety-related symptoms. Furthermore, PB was examined as a moderator on the sexism-symptomatology (depression and anxiety) links. Methods: In a cross-sectional study design, female university students (N = 186) self-reported perceived PB, sexist events, and symptoms of depression and anxiety. Results: Regression analyses revealed that compared to optimal PB, both maternal and paternal affectionless control and neglectful parenting significantly predicted depressive symptoms, whereas symptoms of anxiety were only significantly higher in paternal affectionless control profiles. Frequent sexual discrimination significantly predicted greater depression and anxiety symptomatology, and paternal but not maternal bonding moderated these relations. Non-optimal paternal bonding strengthened the relationships of sexism with symptoms of depression and anxiety, while for optimal paternal bonding, no significant link between sexism and depression was present. Conclusion: The findings indicate direct associations of both non-optimal PB and sexual discrimination with symptoms of depression and anxiety, and provide preliminary evidence that the sexism-symptomatology link might be more pronounced in non-optimal than optimal paternal bonding profiles. This study highlights the centrality of positive father-daughter relationships and sets implications for future research, parenting practices and intervention programs.Show less
Objective: To explore the relationship between peak melatonin levels and depression scores in patients with rheumatoid arthritis and whether this relationship is mediated by pain, fatigue or...Show moreObjective: To explore the relationship between peak melatonin levels and depression scores in patients with rheumatoid arthritis and whether this relationship is mediated by pain, fatigue or disease activity. Methods: This study was of a cross-sectional, analytical and retrospective design using baseline data of an intervention study. Participants with rheumatoid arthritis were recruited and a total of 30 participants (7 males (23%) and 23 females (77%)) between the ages of 26 and 74 years (M=55.2 and SD=10.74) were analysed in this study. The measures of the study included peak melatonin levels, the IRGL (pain), HADS (depression), DAS-28 (disease activity) and CIS-8 (fatigue). Spearman’s correlations were used to analyse the relationships between all the variables and PROCESS.spss was used to conduct mediation analyses. Results: There was a significant negative relationship between peak melatonin levels and depression scores (p=.039), a significant positive relationship was found between depression and fatigue (p<.001) and a significant positive relationship was found between pain and disease activity (p=.018). The mediation analyses did not reveal any potential mediators. Conclusion: Melatonin is linked to depression; however, this link cannot be explained by the mediators listed in this study and further examination of this link is needed. While there were no potential mediators between melatonin and depression, the relationships found between depression and fatigue as well as between pain and disease activity could be explained by the overlap in the items in the various measurements.Show less
Background: Depression symptoms are common in Rheumatoid Arthritis (RA) patients. This could be caused by the limited activities of daily life experienced by RA patients as well as by the...Show moreBackground: Depression symptoms are common in Rheumatoid Arthritis (RA) patients. This could be caused by the limited activities of daily life experienced by RA patients as well as by the inflammation pathways altered by RA which are known to influence depression. Bright light therapy (BLT) has previously shown to be effective to tackle depression caused by an altered circadian rhythm. As a disrupted circadian rhythm is also common in RA patients, BLT might be effective as therapy to treat depression in RA. Objective: The goal of the present study is to examine the effects of BLT on depression and mental health, as well as to explorative examine whether this effect is mediated by changes in circadian rhythmicity in RA patients. Method: This study is a randomized, double-blind, parallel-arm, placebo controlled single center pilot trial study. It consists of 48 RA patients, divided into intervention group with active BLT, and control group with sham BLT. Measurements were taken at three periods: baseline (T0), at the end of the 4-week with BLT (T1), and at follow-up four weeks after BLT (T2). Measurement tools used consisted of a depression scale (HADS) and a mental health scale (RAND 36), as well as the time point of melatonin onset measured by the Dim Light Melatonin Onset test (DLMO). BLT was administered with Luminette glasses which emitted a different color for the intervention group (blue light, to induce circadian phase shift) compared to control group. Results: The results suggest that there is no significant difference with regards to depression, mental health and DLMO between the two groups in the changes between the measurement points from T0 to T1 and from T0 to T2. No significant results were found with regards to the mediating role of DLMO in the relationship between group and depression and mental health. Conclusion: No significant effects of group were found in the present study, with regards to changes in depression, mental health and DLMO, and no mediation effect of the DLMO in the relation between group, depression, and mental health was found. A possible explanation is the low levels of depression reported by the participants at baseline. Further studies are required before disregarding BLT as a potential therapeutic tool to treat depression in RA patients.Show less
This thesis examines how the poetic works of Thomas Hoccleve and Christopher Smart indicate that each poet may have experienced some form of depression.
