Freek Lötters

Effects of controlled inspiratory muscle training in patients with COPD: a meta-analysis

The purpose of this meta-analysis is to review studies investigating the efficacy of inspiratory muscle training (IMT) in chronic obstructive pulmonary disease (COPD) patients and to find out whether patient characteristics influence the efficacy of IMT. A systematic literature search was performed using the Medline and Embase databases. On the basis of a methodological framework, a critical review was performed and summary effect-sizes were calculated by applying fixed and random effects models. Both IMT alone and IMT as adjunct to general exercise reconditioning significantly increased inspiratory muscle strength and endurance. A significant effect was found for dyspnoea at rest and during exercise. Improved functional exercise capacity tended to be an additional effect of IMT alone and as an adjunct to general exercise reconditioning, but this trend did not reach statistical significance. No significant correlations were found for training effects with patient characteristics. However, subgroup analysis in IMT plus exercise training revealed that patients with inspiratory muscle weakness improved significantly more compared to patients without inspiratory muscle weakness. From this review it is concluded that inspiratory muscle training is an important addition to a pulmonary rehabilitation programme directed at chronic obstructive pulmonary disease patients with inspiratory muscle weakness. The effect on exercise performance is still to be determined.

Prognostic factors for duration of sickness absence due to musculoskeletal disorders

Objective:The purpose of this prospective cohort study with 1-year follow-up was to determine prognostic factors for duration of sickness absence due to musculoskeletal disorders. Methods:Workers were included when on sickness absence of 2 to 6 weeks due to musculoskeletal disorders. A self-administered questionnaire was used to collect personal and work-related factors, pain, functional disability, and general health perceptions. Statistical analysis was done with Cox proportional hazard regression with an interaction variable with time for every risk factor of interest. Univariate and multivariate analyses were performed on musculoskeletal disorders and, separately, for low back pain. Results:The main factors that were associated with longer sickness absence were older age, gender, perceived physical workload, and poorer general health for neck, shoulder and upper extremity disorders, and functional disability, sciatica, workers own perception of the ability of return to work, and chronic complaints for low back pain. Workers with a high perceived physical work load returned to work increasingly slower over time than expected, whereas workers with a high functional disability returned to work increasingly faster over time. Conclusions:High pain intensity is a major prognostic factor for duration of sickness absence, especially in low back pain. The different disease-specific risk profiles for prolonged sickness absence indicate that low back pain and upper extremity disorders need different approaches when applying intervention strategies with the aim of early return to work. The interaction of perceived physical workload with time suggests that perceived physical workload would increasingly hamper return to work and, hence, supports the need for workplace interventions among workers off work for prolonged periods.

The prognostic value of depressive symptoms, fear-avoidance, and self-efficacy for duration of lost-time benefits in workers with musculoskeletal disorders

Background: The psychological factors of depressive symptoms, fear-avoidance, and self-efficacy are deemed to be important in the work disability process. However, the prognostic value of these factors for time on benefit is not well understood. Aims: To analyse the prognostic value of psychological factors for the number of days on total compensation benefit over a 12 month period. Methods: In a longitudinal study of 187 workers receiving total compensation benefits due to musculoskeletal disorders, the prognostic value of psychological factors measured 4–5 weeks post-injury for duration on total compensation benefit over 12 months was analysed. Cox proportional hazard regression analyses were conducted. Special emphasis was given to variable selection and to the analysis of confounding effects of potential prognostic variables. Results: The final model indicated that increased depressive symptoms and poorer physical health significantly increase the number of days on total benefit. Confounders included in the final model were pain and fear of income loss. In the final model the impact of fear-avoidance ceased to be significant when work related variables were included in the fully adjusted model. This illustrates that interrelationships between variables must be taken into account when building multivariate prognostic models. The addition of work related variables to the model did not result in any major changes in the adjusted model, which suggests that when measured 4–5 weeks post-injury, psychological and physical health factors are strong predictors of time on benefits, while work conditions are less important. Conclusion: Results suggest that the presence of depressive symptoms and poor physical health in workers on benefit due to musculoskeletal disorders increases the number of days on total compensation benefits significantly, when controlling for confounding variables.

Health status, its perceptions, and effect on return to work and recurrent sick leave

Study Design. Prospective cohort study with 1-year follow-up. Objectives. The purpose of this study is to describe the improvement in several health outcomes during sick leave resulting from musculoskeletal disorders and in the first months after return to work (RTW), and to evaluate the personal and work-related factors associated with these health outcomes, in order to provide some insight in the timing of RTW. Summary of Background Data. Although improvements in pain perception and functional disability appear to be associated with time of RTW, little is known about the required improvement enabling RTW, the additional health improvement after RTW, and whether the health status at the time of RTW is associated with the probability of a recurrence of sick leave. Methods. Workers were included when on sickness absence between 2 to 6 weeks due to musculoskeletal disorders. Self-administered questionnaires at baseline, after RTW, and at 12-month follow-up were used to collect information on changes in symptom status, functional status, and general health. Results. All health outcomes were improved significantly at the time of RTW, whereas perceived pain, functional disability, and physical health also improved significantly in the first months after RTW. Previous sick leave 12 months before study entry was significantly associated with the level of functional disability and general health at time of RTW and also predictive for recurrence of sickness absence. Personal and work-related factors showed little, if any, association with health status at RTW and improvement thereafter. Conclusions. Being fully recovered is not a stipulation for regaining work activities. We hypothesize that workers with musculoskeletal disorders may need additional medical guidance shortly after RTW, especially those with a history of sick leave.

The influence of re-employment on quality of life and self-rated health, a longitudinal study among unemployed persons in the Netherlands

BackgroundUnemployed persons have a poorer health compared with employed persons and unemployment may cause ill health. The aim of this study was to investigate the effect of re-employment on quality of life and health among unemployed persons on social benefits.MethodsA prospective study with 18 months follow-up was conducted among unemployed persons (n=4,308) in the Netherlands, receiving either unemployment benefits or social security benefits. Quality of life, self-rated health, and employment status were measured at baseline and every 6 months of follow up with questionnaires. Generalized estimating equations (GEE) modeling was performed to study the influence of re-employment on change in self-rated health and quality of life over time.ResultsIn the study population 29% had a less than good quality of life and 17% had a poor self-rated health. Persons who started with paid employment during the follow-up period were more likely to improve towards a good quality of life (OR 1.76) and a good self-rated health (OR 2.88) compared with those persons who remained unemployed. Up to 6 months after re-employment, every month with paid employment, the likelihood of a good quality of life increased (OR 1.12).ConclusionsStarting with paid employment improves quality of life and self-rated health. This suggests that labour force participation should be considered as an important measure to improve health of unemployed persons. Improving possibilities for unemployed persons to find paid employment will reduce socioeconomic inequalities in health.

Evaluating an integrated neighbourhood approach to improve well-being of frail elderly in a Dutch community: A study protocol

BackgroundAn important condition for independent living is having a well-functioning social network to provide support. An Integrated Neighbourhood Approach (INA) creates a supportive environment for the frail elderly, offering them tailored care in their local context that allows them to improve self-management abilities and well-being. The purpose of our research is to investigate how an INA can contribute to outcomes of frail elderly and the cost-effectiveness of such a program. The first central study question is: To what extent does INA contribute to (a) continuous, demand-driven, coordinated care and support for the independently- living frail elderly; (b) improvement of their well-being and self-management abilities; and (c) reinforcement of their neighbourhood networks. The second central research question is: is the INA a cost-effective method to support the frail, independently- living elderly?MethodsWe investigate a Dutch INA. This transition experiment aims to facilitate the independently-living frail elderly (70+) to live the life they wish to live and improve their well-being. The study population consists of independently-living frail elderly persons in Rotterdam. The transition experiment starts in two Rotterdam districts and is later extended to two other districts. We propose a concurrent mixed methods design, that is, a combination of qualitative and quantitative research methods to evaluate processes, effects and costs of INA. Such a design will provide insight into an on-going INA and demonstrate which of its elements are potentially (cost)-effective for the frail elderly.DiscussionWe embrace a wide range of scientific methodologies to evaluate the INA project and obtain information on mechanisms and contexts that will be valuable for decision making on local and national levels. The study will lead to a better understanding of how to provide support via social networks for the frail elderly and add to the knowledge on the feasibility and cost-effectiveness of the program in maintaining or improving their well-being. Last, the study will highlight the factors that determine the programs success or failure.

Interrelationships between pain, disability, general health, and quality of life and associations with work-related and individual factors: a study among workers on sickness absence for 2 to 6 weeks for musculoskeletal complaints.

Study Design. A cross-sectional study. Objectives. To measure interrelationships among pain, functional disability, general health, and overall quality of life for workers on sickness absence for 2 to 6 weeks due to musculoskeletal complaints, and to assess the impact of work-related and individual characteristics on these different health dimensions. The results of this study will contribute to a better understanding of the relationship between health and functional disability. Summary of Background Data. When choosing a patient-based outcome measure, different health dimensions must be considered. For musculoskeletal complaints, four health dimensions are important: pain, disability, general health, and overall quality of life. Improvement at one dimension does not necessarily correlate with better health on another dimension. Moreover, correlations between different dimensions may be influenced by individual and environmental factors. However, it is not known whether these factors influence different health dimensions differently. Methods. A total of 218 workers on sickness absence for 2 to 6 weeks due to musculoskeletal complaints completed a questionnaire on four different health dimensions and work-related and environmental factors. Results. Moderate correlations (r < 0.50) among measures of pain, disability, general health, and quality of life were found. These health dimensions were not influenced by work-related physical and psychosocial workload, suggesting no impact of recall bias in studies for work-related musculoskeletal complaints. Self-perceived ability to return to work within 6 weeks explained 21% to 26% of the outcomes on pain and disability and contributed less to the generic measures of health. Conclusion. Within a population of workers on sickness absence for 2 to 6 weeks, specific dimensions of pain and disability seem to be more appropriate measures of health than generic instruments of general health and quality of life.

Public Insurance Systems: A Comparison of Cause-Based and Disability-Based Income Support Systems

This chapter examines eight disability insurance systems, four cause-based systems, and four disability-based systems, in order to draw attention to the importance of system rules as contextual factors in the return-to-work process affecting people with work disability. Part 1 looks at workers’ compensation, no-fault automobile insurance, crime victims’ compensation and accident compensation, four cause-based systems, and draws on examples from Canada, the United States, Australia, and New Zealand. Part 2 looks at the situation in four European countries, where sickness and disability insurance are available: the Netherlands, Sweden, France, and Italy. This chapter draws attention to regulatory factors that can either promote or hinder return to work, and explains how cause-based systems introduce obstacles that limit the system’s ability to support workers in the return-to-work process because of the need to prove causation of disability to justify interventions. It examines various regulatory incentives for promoting return to work in different jurisdictions and concludes by underlining the importance of considering specific system effects, acknowledging that each system is different and has its own positive and negative effects on the worker and the work environment. These issues will have repercussions both for the design of a study in a given jurisdiction or for the development of a disability prevention practice.

Physical activity differences between children from migrant and native origin

BackgroundChildren from migrant origin are at higher risk for overweight and obesity. As limited physical activity is a key factor in this overweight and obesity risk, in general, the aim of this study is to assess to what degree children from migrant and native Dutch origin differ with regard to levels of physical activity and to determine which home environment aspects contribute to these differences.MethodsA cross-sectional survey among primary caregivers of primary school children at the age of 8–9 years old (n = 1943) from 101 primary schools in two urban areas in The Netherlands. We used bivariate correlation and multivariate regression techniques to examine the relationship between physical and social environment aspects and the child’s level of physical activity. All outcomes were reported by primary caregivers. Outcome measure was the physical activity level of the child. Main independent variables were migrant background, based on country of birth of the parents, and variables in the physical and social home environment which may enhance or restrict physical activity: the availability and the accessibility of toys and equipment, as well as sport club membership (physical environment), and both parental role modeling, and supportive parental policies (social environment). We controlled for age and sex of the child, and for socio-economic status, as indicated by educational level of the parents.ResultsIn this sample, physical activity levels were significantly lower in migrant children, as compared to children in the native population. Less physical activity was most often seen in Turkish, Moroccan, and other non-western children (p < .05).ConclusionsAlthough traditional home characteristics in both the physical, and the social environment are often associated with child’s physical activity, these characteristics provided only modest explanation of the differences in physical activity between migrant and non-migrant children in this study. The question arises whether interventions aimed at overweight and obesity should have to focus on home environmental characteristics with regard to physical activity.

Work Absenteeism and Productivity Loss at Work

This chapter presents an overview of key findings related to health-related productivity costs, as a consequence of sickness absence, and productivity loss at work. It shows that the costs of disease-related absence from work and productivity loss at work can be substantial, especially for musculoskeletal and mental disorders. Regarding the monetary valuation of absenteeism, the current methodological debate focuses on the extent of compensation mechanisms and the impact of team production, deadlines etc. on the value of productivity loss. In addition, we observed several ways to measure and value productivity loss at work (presenteeism). Initiatives to improve the measurement and valuation of presenteeism are currently being undertaken worldwide. Especially, the measurement and valuation of long-term presenteeism (for example due to chronic and/or episodic disorders) should become subject of future research, as it might have a substantial impact on the employability and working careers of these chronically ill persons.