Joris P. J. Slaets

Universal risk factors for multifactorial diseases: LifeLines: a three-generation population-based study.

The risk for multifactorial diseases is determined by risk factors that frequently apply across disorders (universal risk factors). To investigate unresolved issues on etiology of and individual’s susceptibility to multifactorial diseases, research focus should shift from single determinant-outcome relations to effect modification of universal risk factors. We present a model to investigate universal risk factors of multifactorial diseases, based on a single risk factor, a single outcome measure, and several effect modifiers. Outcome measures can be disease overriding, such as clustering of disease, frailty and quality of life. “Life course epidemiology” can be considered as a specific application of the proposed model, since risk factors and effect modifiers of multifactorial diseases typically have a chronic aspect. Risk factors are categorized into genetic, environmental, or complex factors, the latter resulting from interactions between (multiple) genetic and environmental factors (an example of a complex factor is overweight). The proposed research model of multifactorial diseases assumes that determinant-outcome relations differ between individuals because of modifiers, which can be divided into three categories. First, risk-factor modifiers that determine the effect of the determinant (such as factors that modify gene-expression in case of a genetic determinant). Second, outcome modifiers that determine the expression of the studied outcome (such as medication use). Third, generic modifiers that determine the susceptibility for multifactorial diseases (such as age). A study to assess disease risk during life requires phenotype and outcome measurements in multiple generations with a long-term follow up. Multiple generations will also enable to separate genetic and environmental factors. Traditionally, representative individuals (probands) and their first-degree relatives have been included in this type of research. We put forward that a three-generation design is the optimal approach to investigate multifactorial diseases. This design has statistical advantages (precision, multiple-informants, separation of non-genetic and genetic familial transmission, direct haplotype assessment, quantify genetic effects), enables unique possibilities to study social characteristics (socioeconomic mobility, partner preferences, between-generation similarities), and offers practical benefits (efficiency, lower non-response). LifeLines is a study based on these concepts. It will be carried out in a representative sample of 165,000 participants from the northern provinces of the Netherlands. LifeLines will contribute to the understanding of how universal risk factors are modified to influence the individual susceptibility to multifactorial diseases, not only at one stage of life but cumulatively over time: the lifeline.

The development of a scale to measure personal reflection in medical practice and education

Aim: Personal reflection is important for acquiring, maintaining and enhancing balanced medical professionalism. A new scale, the Groningen Reflection Ability Scale (GRAS), was developed to measure the personal reflection ability of medical students. Method: Explorative literature study was conducted to gather an initial pool of items. Item selection took place using qualitative and quantitative methods. Medical teachers screened the initial item-pool on relevance, expert-analysis was used for screening the fidelity to the criterion and large samples of medical students and medical teachers were used to investigate the psychometric characteristics of the items. Finally, explorative factor analysis was used to investigate the structure of the scale. Results: The psychometric quality and content validity of the GRAS are satisfactory. The items cover three aspects of personal reflection: self-reflection, empathetic reflection and reflective communication. The 23-item scale proved to be easy to complete and to administer. Conclusion: The GRAS is a practical measurement instrument that yields reliable data that contribute to valid inferences about the personal reflection ability of medical students and doctors, both at individual and group level.

How to understand and improve older people’s self-management of wellbeing

This paper addresses the question of how older people can be supported to actively self-manage their own process of ageing such that overall wellbeing is achieved and maintained for as long as possible. Starting from a resource-based approach, a new theory of self-management of wellbeing (SMW theory) is proposed, and it is shown how it can be used as a basis for the design of self-management interventions for ageing successfully. The main aspects of the theory, i.e. six key self-management abilities and the core dimensions of wellbeing, are presented as well as the theory-based ‘blueprint’ for the design of interventions. Empirical results of two intervention studies are briefly presented and show that the SMW theory may be a useful tool for the design and evaluation of interventions for successful ageing.

The effect of music therapy compared with general recreational activities in reducing agitation in people with dementia: a randomised controlled trial

This study aimed to compare the effects of music therapy with general recreational day activities in reducing agitation in people with dementia, residing in nursing home facilities.

The effect of social comparison information on the life satisfaction of frail older persons

In this study, the authors examined the effects of social comparison on the life satisfaction of 455 community-dwelling older persons. These older persons were confronted with a fictitious interview with either an upward or a downward target. After downward comparison, older persons felt more satisfied with their lives than after upward comparison, especially those who had higher levels of frailty. These effects were only found with lower levels of identification. Apparently, downward comparison only serves its self-enhancing function on life satisfaction among frail older persons when they perceive the comparison target as different from themselves.

Prenatal exposure to the 1957 influenza pandemic and non-affective psychosis in The Netherlands

Second-trimester exposure to the 1957 A2 influenza pandemic is a controversial risk factor for schizophrenia. Two earlier studies of the Dutch psychiatric registry failed to find an increased risk for exposed subjects, but diagnostic misclassification within the spectrum of non-affective psychoses has not yet been ruled out as an explanation for the negative findings. Using an enlarged data-set we examined not only whether second-trimester exposure to the epidemic is associated with an increased risk of schizophrenia (ICD:295), but also whether it is associated with an increased risk of paranoid states (ICD:297) or other non-organic psychoses (ICD:298). In this retrospective cohort study the risks of the above-mentioned disorders were compared for those exposed and unexposed to A2 influenza during the second trimester of fetal life. The risks for the exposed subjects were not significantly higher than the risks for the unexposed. The power of the study to detect a significant increase in the risk of schizophrenia was sufficient. If the relative risk of a lifetime hospitalization for schizophrenia for second-trimester exposed subjects (born January-April 1958) is assumed to be 1.3, the power of the study would be 0.97 (alpha=0.05; one-tailed testing). If the relative risk for subjects born five months after the peak of the epidemic (mid-February to mid-March 1958) is assumed to be 1.88, as reported for England and Wales, the power of the study would be close to 1.00. This was the largest study of its kind in Europe: 275 subjects were born in the period January-April 1958 and had a lifetime hospitalization for schizophrenia. This study indicates that there is no relation between second-trimester exposure to the 1957 influenza pandemic and risk of non-affective psychosis in the Dutch population. It adds to a growing body of work which does not support an association between maternal influenza and schizophrenia.

Structured analyses of interventions to prevent delirium.

Delirium is one of the most serious complications in hospitalized elderly, with incidences ranging from 3–56%. The objective of this meta‐analysis was two‐fold, first to investigate if interventions to prevent delirium are effective and second to explore which factors increase the effectiveness of these interventions.

Association of Cognitive Function with Albuminuria and eGFR in the General Population

BACKGROUND AND OBJECTIVES Recent studies found different associations of cognitive function with albuminuria or estimated GFR (eGFR). Most studies were limited to the elderly or did not take both renal variables into account. Therefore, this study analyzed the association of cognitive function with albuminuria and eGFR in community-dwelling persons aged 35 to 82 years. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS This was a cross-sectional study comprising 4095 participants of the Prevention of Renal and Vascular End-Stage Disease (PREVEND) study. Cognitive function, measured with the Ruff Figural Fluency Test (RFFT), was treated as the dependent variable, and albuminuria and eGFR were treated as independent variables. RESULTS The prevalence of albuminuria <10, 10 to 29, and ≥30 mg/24 h was 54%, 31%, and 15%, respectively. Mean eGFR (± SD) was 79 ± 15 ml/min per 1.73 m(2). Because of interaction between albuminuria and age, analyses were performed per age tertile. After multivariate adjustment, albuminuria ≥ 30 mg/24 h, but not eGFR, was associated with lower RFFT score in the youngest tertile (B -5.3; 95% CI, -0.6 to -9.2; P = 0.05), but not in older tertiles. Moreover, subjects in the youngest tertile with increasing albuminuria (5-15 and >15 mg/24 h) before RFFT measurement had lower mean RFFT scores than subjects with stable albuminuria: mean difference -4.9 (P = 0.3) and -6.7 (P = 0.03), respectively. CONCLUSIONS In this community-based cohort, elevated albuminuria was associated with worse cognitive function in young but not in old persons. There was no association of eGFR with cognitive function.

Outcomes of a Geriatric Liaison Intervention to Prevent the Development of Postoperative Delirium in Frail Elderly Cancer Patients: Report on a Multicentre, Randomized, Controlled Trial

Background Delirium is a serious and common postoperative complication, especially in frail elderly patients. The aim of this study was to evaluate the effect of a geriatric liaison intervention in comparison with standard care on the incidence of postoperative delirium in frail elderly cancer patients treated with an elective surgical procedure for a solid tumour. Methods Patients over 65 years of age who were undergoing elective surgery for a solid tumour were recruited to a multicentre, prospective, randomized, controlled trial. The patients were randomized to standard treatment versus a geriatric liaison intervention. The intervention consisted of a preoperative geriatric consultation, an individual treatment plan targeted at risk factors for delirium, daily visits by a geriatric nurse during the hospital stay and advice on managing any problems encountered. The primary outcome was the incidence of postoperative delirium. The secondary outcome measures were the severity of delirium, length of hospital stay, complications, mortality, care dependency, quality of life, return to an independent preoperative living situation and additional care at home. Results In total, the data of 260 patients were analysed. Delirium occurred in 31 patients (11.9%), and there was no significant difference between the incidence of delirium in the intervention group and the usual-care group (9.4% vs. 14.3%, OR: 0.63, 95% CI: 0.29–1.35). Conclusions Within this study, a geriatric liaison intervention based on frailty for the prevention of postoperative delirium in frail elderly cancer patients undergoing elective surgery for a solid tumour has not proven to be effective. Trial Registration Nederlands Trial Register Trial ID NTR 823

Development and measurement properties of the self assessment version of the INTERMED for the elderly to assess case complexity

OBJECTIVES The INTERMED for the Elderly Self Assessment (IM-E-SA) was developed to support health care professionals in providing demand driven elderly care. It assesses case complexity and health care needs as perceived by older adults themselves. By applying this instrument tailored care can be provided as it supports professionals in their allocation decisions. The aim was to evaluate the measurement properties of the IM-E-SA. METHODS In this cross-sectional study 338 elderly people completed a postal questionnaire and participated in an interview. Feasibility of the IM-E-SA was assessed by determining the percentages of missing values per item. Reliability of the IM-E-SA was expressed as Cronbachs alpha. Intraclass correlation coefficients (ICCs) were calculated between the IM-E-SA and IM-E. Nonparametric tests were applied to assess if the IM-E-SA could distinguish between subgroups of elderly adults who differed on demographic characteristics and the prevalence of diseases/disorders. Convergent validity and discriminant validity were assessed using Spearman rank correlations between the IM-E-SA and IM-E, life satisfaction (Cantrils Ladder of Life), activities of daily living (Katz extended), quality of life (EQ-5D), mental health (SF-36) and prevalence of diseases/disorders. RESULTS Percentages of missing values per IM-E-SA item ranged from 0 to 5%. Cronbachs alpha was .78. The ICC between the total scores of the IM-E-SA and the IM-E was .68. The IM-E-SA yielded statistically significant differences between subgroups (known-group validity). Correlations evaluating the convergent validity were moderate to strong (.50-.70). Those correlations assessing the discriminant validity were moderate (.38-.53). CONCLUSION This study supports the feasibility, reliability and validity of the IM-E-SA.