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PhD Defence Lizhen Ye

This thesis examines the interrelations and contributing factors of frailty, polypharmacy, medication-related problems, and loneliness in older European community-dwelling adults, using data from the Urban Health Centres Europe (UHCE) Project. It is structured into three main parts:

Part I focuses on frailty, divided into physical, psychological, and social domains. Findings indicate various demographic, lifestyle, and health factors associated with these frailty domains. Notably, physical frailty was shown to have a reciprocal relationship with psychological frailty and a unidirectional association with social frailty, highlighting the complex interplay between these domains.

Part II investigates the factors linked with polypharmacy and a high risk of medication-related problems. Significant associations were found with sociodemographic characteristics, health status, and healthcare usage. Additionally, a cycle was observed where higher levels of frailty increased the risk of medication-related problems, which in turn could lead to increased frailty, suggesting a bidirectional relationship.

Part III explores the relationship between loneliness and frailty. It was found that loneliness, particularly social loneliness, significantly contributes to all frailty domains. A bidirectional association between overall loneliness and frailty was identified, with emotional loneliness specifically influencing psychological frailty.

The thesis underscores the need for a holistic approach to address these interconnected issues, recommending the integration of medical, psychological, and social elements into health strategies to enhance aging well-being and resilience.

Value-based healthcare in inherited bleeding disorders

Value-based healthcare (VBHC) was first introduced in 2006 as a strategy to combat the rising healthcare cost and unwanted variation in outcomes and quality of care. According to VBHC framework, healthcare organizations should aim to maximize patient value, where value is defined as the health outcomes that matter to patients relative to the cost of achieving those outcomes. From 2011 onwards, hospitals in the Netherlands have been implementing VBHC principles to improve the care for patients with various medical conditions. The Dutch interpretation of VBHC, however, deviates slightly from the original concept. While the objective of maximizing patient value through the routine collection of outcomes that matter to patients prevails, Dutch healthcare organizations often bypass the immediate need to measure cost. In addition, in the Dutch context, emphasis is placed on the use of outcome information to improve shared decision making and to create a culture of continuous learning and quality improvement.

This PhD thesis aimed to assess the added value of the implementation of VBHC, as defined within the Dutch healthcare context, in routine clinical care for patients with an inherited bleeding disorder. To achieve this aim, this thesis includes research on all the steps necessary to facilitate the implementation and evaluation of VBHC in this patient population. This thesis provides a recommendation on which patient-reported outcomes should be measured in the care for patients with inherited bleeding disorders, and which patient-reported outcomes should be used to collect these outcomes. In addition, this thesis provides insight into the possible variation in the care provision for patients with hemophilia which can be used as both a starting point for continuous learning and quality improvement initiatives, as well as guide the collection and use of outcome information. Moreover, this thesis provides insight into patient experiences with the collection of outcome information in routine care provision.

The main aims of this thesis are to study i) the association between psychosocial factors and mental health among university students, and ii) the influence of mental health on work participation.

In the first part of the thesis, potential determinants of students’ mental health were investigated. Chapter 2 and chapter 4 investigate the associations between the dimensions of the effort-reward imbalance (ERI) model and, respectively, psychological distress and burnout symptoms among Italian university students. These studies were among the first using the ERI model in the university setting as determinant of mental health outcomes among university students. Chapter 2 presents a cross-sectional study among 4760 students. In the sample, more than one out of three students experienced severe psychological distress. Moreover, effort, reward, ERI, and overcommitment were found to be associated with psychological distress, in particular with severe psychological distress. Moreover, ERI and overcommitment partially explained the higher prevalence of psychological distress among female students, suggesting that part of the gender difference in psychological distress may be explained by psychosocial factors. Chapter 3 provides additional evidence about potential targets for interventions by showing that student life challenges, in particular high workload, faculty shortcomings and unsupportive climate, were associated with students’ mental and self-rated health. Notably, the between-within model utilized in chapter 3 and chapter 4 allows to investigate both differences between individuals and changes within individuals over time. Results indicate that, while most of the variance in exposure is attributable to difference between individuals, this exposure may change to some extent within individuals even within a relative short timeframe. This suggests that tackling the exposure in student life challenges, ERI and overcommitment may result in better mental health among students. Additionally, chapter 5 studied in across-sectional study among 1858 Italian medical students the psychometric properties of the Italian version of the University Stress Scale (USS) as a tool to measure sources of academic stress. Results suggests that the use of a short version of the scale (USS-S) is preferable to assess the level of students’ stress compared to the 19 item version.

In the second part of the thesis the consequences of mental health problems on work participation were studied. Chapter 6 and chapter 7 illustrate different mechanisms of the negative impact of mental health problems on work participation. Using register information of 2,346,393 young adults who graduated from secondary vocational and higher vocational education or university, chapter 6 contributes to the literature suggesting that mental disorders during later stages of higher education may negatively impact work participation via two mechanisms. On the one hand, students who experience a mental health problem in the year before completing higher education were less likely to enter paid employment during 10 years of follow-up. On the other hand, graduates who entered paid employment were more likely to exit from paid employment during the follow-up period. Meanwhile, differences across type of disorders in the association between mental disorders and work participation were identified. Chapter 7 investigated in a longitudinal study the association between depressive symptoms among 5,263 older European workers and early exit from paid employment during four years follow-up differentiating exit due to unemployment and disability. The study showed that depressive symptoms were associated with higher risk of early exit from paid employment via disability benefits among men and women and, to a much lesser extent, also unemployment among men.

Chapter 8 provides insights about the available literature concerning mental health among students in higher education, with recommendations for future research. Refining methodologies in prevalence estimation of mental problems and a comprehensive investigation of individual and environmental determinants are crucial. Given its more advanced state, research on mental health in the workforce may inform student-focused research.

In the general discussion, methodological implications of the studies included in this thesis are discussed, together with an overall frame of observational studies in mental health. In particular, the definitions of mental health and mental disorders together with strategies to assess them are discoursed. The complexity behind the concept of mental health and mental disorders requires further reflections over their definition, and transdisciplinary efforts to investigate their multifaceted concepts. Recommendations for policy and practice, and students are also discussed. In particular, the development of interventions aiming at primary prevention for mental health problems is recommended, together with efforts toward a more inclusive labor market / academic environment. A safe psychosocial academic environment is needed. Students are invited to invest resources in protecting their own mental health and passion, as a personal and professional investment.

Lastly, opportunities offered by social media to researchers are discussed. Social media may enable researchers to bidirectionally connect with the public, offering the opportunity to improve the quality and the communication of one’s research. Visibility on social media may also lead to scientific cooperation, invitations to academic events and teaching opportunities. Overall, social media can help public health researchers to make their work more meaningful, and can remind them why they do it.

In the thesis “Health Effects of Lifestyle Promotion among Youth,” two main objectives are leading: 1.) the association between organized activities and mental health in children and adolescents, and 2.) the long-term effects of primary school-based interventions for the prevention of obesity.

The first part demonstrates favorable associations between organized sports activities and mental health in children and adolescents. There was insufficient evidence available to draw conclusions about the relationship between other types of organized activities and mental health. Organized sports activities are a promising starting point for future interventions to prevent mental health problems.

The second part investigates the long-term effects of primary school-based interventions for obesity prevention. A systematic review and meta-analysis found no convincing evidence for long-term effects on indicators of overweight and obesity. In a naturalistic effect evaluation and longitudinal cohort study no positive long-term effects of Lekker Fit! on a broad set of health outcomes were found.

The thesis emphasizes the need for continuous monitoring of intervention effects and more initiatives to improve fitness among youth in the city of Rotterdam. For effective obesity prevention, additional interventions or extension of existing programs to secondary schools might be necessary.

The diagnosis, treatment, and consequences of cancer can impact patients and their informal caregivers greatly. They are confronted with complex care provided by various healthcare professionals. At the same time, tasks and relationships at home and work change. These fluctuating cancer-related challenges can result in unmet care needs. Supportive care is important for patients with cancer and their informal caregivers to deal with these (unmet) needs. In this stressful situation, some patients and their relatives struggle to find appropriate supportive care. Next to this, the disease also has an impact on the healthcare system. The demand for and costs of the healthcare system are on the rise, and simultaneously, there are fewer resources available to address the needs of patients with cancer.

Thus, it is crucial to develop a strategic approach to provide appropriate, personalized, and adequate supportive care in order to address the psychosocial and informational needs of patients and their informal caregivers, while taking into account the costs of and demand for care in the future. As a result, this dissertation adopts a novel perspective by focusing on the role of designated ‘Centers for information and support’ in providing supportive care. Such centers offer multiple types of informal care together with non-medical formal care, complementary to, and in close collaborate with, medical formal care provided by the hospital. The central goal of this dissertation was to optimize supportive care in patients with cancer and their relatives. This central goal is divided into two aims: 1) to gain a better understanding in the services of centers for information and support, the needs of patients with (advanced) cancer and their relatives, and the match between the centers’ services and the needs of patients and their relatives (part I), and 2) to optimize supportive care via the formal care route (part II).

Ever since the General Surgeons report on the harmful effects of tobacco in 1964, tobacco control has had major successes and many countries now aim to reach a smoke-free generation. Despite these successes, smoking related mortality remains an important contributor to socio-economic differences, and the peak of smoking attributable mortality has not been reached yet. To further improve tobacco control and contribute to reaching a smoke-free generation, this thesis discusses two strategies. In pat 1 we investigate extending smoke-free policies beyond smoke-free public places and workplaces. Public support is tremendous, not only in the Netherlands but worldwide and not only among smokers, but among non-smokers as well. Especially places with children are low-hanging fruit to implement smoke-free zones. In part 2 we investigated strategies to improve smoking cessation programs through personalization. External circumstances such as poverty related stress might influence (health) behavior, and a stronger focus to alleviate money-related issues may benefit health interventions. Health behavior is also influenced by personal characteristics, which was the focus in the PERSIST trial. Using personalized incentives we tried to improve sustained smoking cessation among health care employees. Combining a personalized advice with the option to deviate from it seems to be an effective strategy, however recruitment was challenging and future research might benefit from more collaboration between researchers and potential participants. Combining the knowledge gained from part 1 and 2, we concluded that by simultaneously targeting the system and aiding the individual, a smoke-free generation should be in reach.

Injuries are a significant global health concern, contributing to 9% of annual deaths worldwide. Despite advancements in trauma care, survivors grapple with both short and long-term challenges, including physical and mental health issues. This thesis investigates patient outcomes (part I) and costs (part II) post-injury. Part I focuses on assessing outcomes in injury patients and traumatic brain injury patients, highlighting the prevalence of physical and mental health issues and their impact on quality of life, healthcare usage, and return to work. Part II delves into the economic burdens of injuries, revealing variations in healthcare and productivity costs influenced by factors such as injury severity, age, and gender. The research underscores the importance of long-term care planning to mitigate costs and support comprehensive recovery, emphasizing the need for tailored interventions addressing both physical and mental well-being.

The main aim of this thesis is to study individual and family-related factors that are relevant for indicators of child health (i.e. dental caries, weight status), health-related quality of life (HRQoL), and lifestyle behaviours. The following conclusions can be drawn from the studies presented in this thesis. Unhealthy lifestyle behaviours (i.e. skipping breakfast, more social media platforms used, and spending more time on social media) have a negative impact on children’s health outcomes and HRQoL. Multiple individual and family-related factors (i.e. sex, ethnic background, socioeconomic status of a family, and family structure) may affect children’s HRQoL at younger age. Additionally, multiple family-related factors (i.e. family structure and socioeconomic status of a family) independent associated with children’s social media use at younger age. The findings in our study also support the assumption that interventions with multiple levels of influence (e.g. public policy, individual, interpersonal, or organizational) may contribute to policies to address oral health inequalities. The findings presented can support the development of evidence-based preventive interventions, practice guidelines and policies to promote child health and well-being.

In her PhD thesis, Doris van der Smissen describes the development, evaluation and implementation of the web-based advance care planning program ‘Verken uw wensen voor zorg en behandeling’ (English translation: ‘Explore your preferences for treatment and care’). The program was developed and implemented together with patients, relatives and patient organizations.

Advance care planning (ACP) supports the conversation about future treatment and care so that care can be provided in line with people’s preferences. Web-based programs can support people in the first steps of ACP, such as preparing discussions about treatment and care with their relatives and healthcare professionals.

The web-based ACP program supports people in thinking about, discussing and recording of treatment and care preferences. The program contains information, videos and questions. Users can print their answers to the questions. Interviews and the before-and-after evaluation study showed that people found the program user-friendly, understandable and useful. The program supported people with chronic disease in reflecting on preferences for treatment and care and helped them to feel more ready for ACP.

Link to the web-based ACP program: https://www.thuisarts.nl/keuzehulp/verken-uw-wensen-voor-zorg-en-behandeling

Link to PhD thesis: https://www.publicatie-online.nl/publicaties/doris-van-der-smissen, password: 169086

If you are interested to attend the PhD defense, please send an email to promotie.dorisvandersmissen@gmail.com

 

Mental disorders pose an extremely high burden to society, both in terms of their direct effects on health but also societal welfare losses. This burden is distributed unequally and strongly impacts groups of low socioeconomic status (SES). Also unequal is the access and utilization of mental health services, which should be concentrated among those who most need treatment. This thesis aimed to produce evidence to guide mental health policy in reducing inequalities in mental health care and outcomes.

The objective was achieved by addressing two different knowledge gaps. The first research question, descriptive by nature, aimed to complement the existing knowledge about inequalities in the mental health field, which covers disparities in mental health status and access to mental health care but extremely limited in describing inequalities during mental health treatment and patient outcomes. The second research question focused on identifying mental health related interventions, programs and policies that impact the existing inequalities. To address this question, I have relied on quasi-experimental methods to causally evaluate interventions linked to key policy levers in granting access to mental health support: coverage, eligibility, and availability. I have conducted the evaluations applying an equity lens by measuring differential effects by socioeconomic status or focusing on interventions that impact vulnerable groups.