Associations between depressive complaints and indicators of labour participation among older Dutch employees: a prospective cohort study.

PURPOSE: European policy measures have led to an increased net labour participation of older employees. Yet, via different routes (for instance disability schemes) employees still often leave the labour market early. Mental health may be an important factor hindering labour participation. Aims of this study are twofold: first, to examine the relationship between mental health-particularly depressive complaints-and indicators of labour participation among older employees over a 2-year follow-up period and second, to explore the impact of different work contexts when studying this relation. METHODS: A subsample of older employees (aged > 45 years; n = 1253) from the Maastricht Cohort Study was studied. Depressive complaints were assessed using the Hospital Anxiety and Depression scale. Logistic and Cox regression analyses covered 2 years of follow-up and were also stratified for relevant work-related factors. RESULTS: Employees with mild depressive complaints showed statistically significantly higher risks for poor mental workability (HR 2.60, 95% CI 1.14-5.92) and high psychological disengagement levels (HR 2.35, 95% CI 1.21-4.57) over time compared to employees without depressive complaints. Within various work contexts, for instance in which employees perform physically demanding work or have high psychological job demands, significantly stronger associations were found between depressive complaints and poor mental workability over time. CONCLUSIONS: This study shows strong longitudinal associations between depressive complaints and indicators of labour participation, also within different work contexts over time. Results provide valuable input for developing preventive measure aiming to enhance sustainable labour participation of older employees.

Need for recovery and different types of early labour force exit: a prospective cohort study among older workers.

PURPOSE: This study examines the relationship between need for recovery (NFR) and labour force exit (LFE) among older workers. Different types of LFE (early retirement, work disability and unemployment) are considered, and the role of potential confounding and modifying factors, including the availability of early LFE schemes, is examined. Also, associations between NFR and the intention and ability to prolong one's working life, which are known determinants of LFE, are assessed. METHODS: A subsample of older workers from the Maastricht Cohort Study was examined (n = 2312). The relationship between NFR and LFE was investigated by means of Cox regression analyses. Logistic regression analyses were performed to investigate cross-sectional associations between NFR and the intention and ability to prolong working life. RESULTS: Elevated NFR was associated with a higher risk of overall LFE during a 4-year follow-up period (HR 1.39, 95% CI 1.09-1.78), and specifically with a higher risk of leaving the labour force through early retirement and work disability. When early retirement schemes were available, strong and significant associations between NFR and LFE were observed (HR 2.79, 95% CI 1.29-6.02), whereas no significant associations were found when such schemes were unavailable. Older workers with a higher NFR also had earlier retirement intentions and lower self-assessed abilities (both physical and mental) to prolong their working life until the mandatory retirement age. CONCLUSIONS: Because this study shows that NFR is a precursor of LFE among older workers, monitoring NFR is important for timely interventions aimed at reducing NFR to facilitate extended labour participation.

The trait and occasion components of fatigue and their association with sickness absence.

OBJECTIVE: Fatigue is an important health outcome in public and occupational health care. To correctly understand and treat high levels of (prolonged) fatigue it is important to disentangle the state of fatigue into a time-varying (occasion) and -invarying (trait) component. Not only for understanding of the construct itself over time but also for its relation with (health) outcomes such as sickness absence. METHODS: Longitudinal data (n=2316) from the Maastricht Cohort Study (MCS) study was used, which assessed fatigue across 4-month intervals using the Checklist Individual Strength (CIS). RESULTS: It was found that the occasion component explains 27.60% (95%-CI [25.80%; 29.40%]) of the variance of fatigue and the trait component 71.00% (95%-CI [69.00%; 72.90%]). The trait component was, furthermore, found to be a significant predictor of sickness absence. CONCLUSION: Fatigue has a considerable time-invariant component. As this component is also related with other adverse health outcomes, preventive measures and interventions should take the difference between the occasion and trait component of fatigue into account.

Monitoring of need for recovery and prolonged fatigue within the working population: Evaluation of reliability and agreement over time.

BACKGROUND: Need for recovery (NFR) and prolonged fatigue are two important concepts for monitoring short- and long-term outcomes of psychological job demands within employees. For effective monitoring it is, however, important to gain insight in the reproducibility of the instruments that are used. OBJECTIVE: The objective was to assess reproducibility of the NFR scale and Checklist Individual Strength (CIS), measuring NFR and prolonged fatigue respectively, in the working population. METHODS: Longitudinal data from the Maastricht Cohort Study (MCS) study was used, capturing 12,140 employees from 45 different companies at baseline. A 'working' and 'returning to work' sample was conceived for different intervals; 4-month, 1-year, and 2-year. RESULTS: Reliability, assessed with the interclass correlation, was high within employees with a stable work environment for the NFR scale (0.78) and CIS (0.75). The smallest detectable change, assessing the agreement, was 41.20 for the NFR scale and 31.10 for the CIS. CONCLUSIONS: Reliability was satisfactory for both the NFR scale and CIS. The agreement of both scales to detect a changes within employees was, however, less optimal. It is, therefore, suggested that, ideally, both instruments are placed within a broader range of instruments to effectively monitor the outcomes of psychological job demands.

The impact of depression and diabetes mellitus on older workers' functioning.

OBJECTIVE: Using the International Classification of Functioning, Disability and Health as a framework, this study investigates the impact of depression and diabetes mellitus on older workers' functioning (problems with concentration, physical functioning, need for recovery and work and social participation restrictions). The study focuses on how these chronic conditions, in their interaction with the work context, affect older workers' functioning, which may be an important precursor of early retirement. METHODS: Older workers (≥ 45years) with depression (n=127) or diabetes mellitus (n=107) enrolled in the prospective Maastricht Cohort Study (MCS) were followed between October 2008 and October 2012. Linear, logistic and Cox regression analyses were performed to investigate the effect of these health conditions on workers' functioning compared to a reference group of older workers without a chronic condition (n=1612). The interaction with participants' working conditions (psychological job demands, decision latitude and strenuous work) was also analysed. RESULTS: Compared to the reference group, depression and diabetes mellitus were (over time) positively related with need for recovery caseness and restrictions in social participation but not with restrictions in work participation. Depression was positively related with concentration problems and need for recovery, whereas diabetes mellitus was negatively related with physical functioning. Finally, the relationship between functioning and depression and diabetes mellitus depends on working conditions. CONCLUSION: Older workers with depression or diabetes mellitus are vulnerable to losses in specific domains of functioning. The impact on functioning varies across working conditions, providing insight for disease-tailored preventive measures.

The context dependency of the self-report version of the Strength and Difficulties Questionnaire (SDQ): a cross-sectional study between two administration settings.

BACKGROUND: The Strength and Difficulties Questionnaire (SDQ) is a screening instrument for psychosocial problems in children and adolescents, which is applied in "individual" and "collective" settings. Assessment in the individual setting is confidential for clinical applications, such as preventive child healthcare, while assessment in the collective setting is anonymous and applied in (epidemiological) research. Due to administration differences between the settings it remains unclear whether results and conclusions actually can be used interchangeably. This study therefore aims to investigate whether the SDQ is invariant across settings. METHODS: Two independent samples were retrieved (mean age = 14.07 years), one from an individual setting (N = 6,594) and one from a collective setting (N = 4,613). The SDQ was administered in the second year of secondary school in both settings. Samples come from the same socio-geographic population in the Netherlands. RESULTS: Confirmatory factor analysis showed that the SDQ was measurement invariant/equivalent across settings and gender. On average, children in the individual setting scored lower on total difficulties (mean difference = 2.05) and the psychosocial problems subscales compared to those in the collective setting. This was also reflected in the cut-off points for caseness, defined by the 90th percentiles, which were lower in the individual setting. Using cut-off points from the collective in the individual setting therefore resulted in a small number of cases, 2 to 3%, while ∼10% is expected. CONCLUSION: The SDQ has the same connotation across the individual and collective setting. The observed structural differences regarding the mean scores, however, undermine the validity of the cross-use of absolute SDQ-scores between these settings. Applying cut-off scores from the collective setting in the individual setting could, therefore, result in invalid conclusions and potential misuse of the instrument. To correctly apply cut-off scores these should be retrieved from the applied setting.

Need for recovery across work careers: the impact of work, health and personal characteristics.

PURPOSE: Employees experiencing a high need for recovery (NFR) are at risk of long-term adverse effects in both their health and labour participation. So far, the determinants of NFR across age categories remain unknown. The aim of this study is to investigate the determinants of the NFR among employees in three age categories (30-44, 45-54 and 55-65 years), for men and women separately. METHODS: The study was based on data from the prospective Maastricht Cohort Study. Wave T3 (May 1999) was chosen as article baseline (n = 7,900). The follow-up period of 20 months included five follow-up waves. Cox regression analyses were performed to investigate the determinants, which originated from the work environment, health and lifestyle and personal domain of employees, of NFR across age categories over time. RESULTS: Cross-sectional results demonstrated substantial differences in mean scores and proportion of cases of NFR across age categories. Longitudinal analyses demonstrated risk factors in the multifactorial aetiology of NFR that played a role in all age categories, but also showed several age-specific risk factors, e.g. low decision latitude appeared to be a risk factor only in the oldest age category. CONCLUSIONS: Although selection effects may have occurred, this study shows that the risk factors for a high NFR were different among the age categories. To prevent and reduce a high NFR among employees, it is important to develop preventive measures that target age-specific risk factors.

Prediction of long-term sickness absence among employees with depressive complaints.

INTRODUCTION: To study the properties of a screening instrument in predicting long-term sickness absence among employees with depressive complaints. METHODS: Employees at high risk of future sickness absence were selected by the screening instrument Balansmeter (BM). Depressive complaints were assessed with the depression scale of the Hospital Anxiety and Depression Scale. The total study population consisted of 7,401 employees. Sickness absence was assessed objectively and analyzed at 12 and 18 months of follow-up using company registers on certified sick leave. RESULTS: The relative risk (RR) for long-term sickness absence, for employees at high risk versus not at high risk, was 3.26 (95% CI 2.54-4.22) in men and 2.55 (1.98-3.35) in women, when the BM was applied in the total study population. The RR of long-term sickness absence of employees with depressive complaints compared with employees without depressive complaints was 3.13 (2.41-4.09) in men and 2.45 (2.00-3.00) in women. The RR of long-term sickness absence for the BM applied in employees with depressive complaints was 5.23 in men and 3.87 in women. When the BM with a cut-off point with a higher sensitivity was applied in employees with depressive complaints, the RR for long-term sickness absence was 4.88 in men and 3.80 in women. CONCLUSIONS: The screening instrument Balansmeter is able to predict long-term sickness absence within employees with depressive complaints. The total prediction of long-term sickness absence proved better in employees with depressive complaints compared with employees of a general working population.

Experience of health complaints and help seeking behavior in employees screened for depressive complaints and risk of future sickness absence.

INTRODUCTION: The aim of this study was to examine the associations between on the one hand depressive complaints and risk of future sickness absence and on the other hand experience of health complaints and help seeking behavior in the working population. METHODS: Cross-sectional data were used from employees working in the banking sector (n = 8,498). The screening instrument included measures to examine the risk of future sickness absence, depressive complaints and help seeking behavior. RESULTS: Of employees reporting health complaints, approximately 80% had already sought help for these complaints. Experience of health complaints and subsequent help seeking behavior differed between employees with mild to severe depressive complaints and employees at risk of future sickness absence. Experience of health complaints was highest in employees identified with both concepts (69%) compared with employees identified at risk of future sickness absence only (48%) and with mild to severe depressive complaints only (57%). In those employees identified with one or both concepts and who had not sought help already, intention to seek help was about 50%. CONCLUSIONS: From a screening perspective, employees who do not experience health complaints or who do not have the intention to seek help may refuse participation in early intervention. This might be a bottleneck in the implementation of preventive interventions in the occupational health setting.

Need for recovery from work in relation to age: a prospective cohort study.

PURPOSE: To investigate the impact of increasing age on the need for recovery (NFR) over time among day workers METHODS: The study is based on data from the first 2 years of follow-up of the Maastricht Cohort Study (n = 7,734). To investigate whether age predicted the onset of elevated NFR, multivariate survival analyses were conducted RESULTS: The highest levels of NFR were observed in the age group of 46-55 years. The relative risk for developing elevated NFR was highest in the age groups 36-45 years (RR 1.30; 1.07-1.58) and 46-55 years (RR 1.25; 1.03-1.52) in men and 46-55 years (RR 1.36; 1.04-1.77) in women when compared to the reference group CONCLUSIONS: While NFR increased with age until the age of 55, this was followed by decreased levels of NFR among older employees. Explanations for the decreasing levels of NFR in the highest age group can be found in several domains such as the work environment, private situation and compensation strategies.

Interpersonal conflicts at work as a predictor of self-reported health outcomes and occupational mobility.

OBJECTIVES: The aim of this prospective study was to examine the relationship between interpersonal conflicts at work and subsequent self-reported health outcomes (self-reported general health, need for recovery, and prolonged fatigue) and occupational mobility (internal mobility ie, changing job function, and external mobility ie, changing employers). METHODS: Data from the Maastricht Cohort Study on fatigue at work (n = 5582 for co-worker conflict; n = 5530 for supervisor conflict) were used. Interpersonal conflict with either co-workers or supervisors was assessed between baseline and 1-year follow-up. Outcomes were studied every 4 months between 1-year and 2-year follow-up. Logistic regression analyses using generalised estimating equations were conducted for each of the dichotomous outcomes, while controlling for demographic factors, the presence of a long-term illness, other workplace stressors, coping, and outcome at baseline. Analyses were conducted for men only. RESULTS: At baseline, conflicts with co-workers occurred in 7.2% of the study population, while conflicts with supervisors occurred in 9.5% of the study population. In general, this study showed that co-worker conflict was a statistically significant risk factor for the onset of an elevated need for recovery, prolonged fatigue, poor general health and external occupational mobility. Supervisor conflict was a significant risk factor for the onset of an elevated need for recovery, prolonged fatigue, external occupational mobility, and internal occupational mobility. CONCLUSIONS: The results of this study indicate a possible causal relationship between interpersonal conflicts at work and self-reported health and occupational mobility. Given the considerable impact of interpersonal conflicts at work on the individual worker and on the organisation, and the fact that interpersonal conflicts at work are highly prevalent, these findings underline the need for interventions aimed at preventing the occurrence of interpersonal conflicts at work, or at least reducing the harmful effects on both the employee and the organisation.

[Aetiology of prolonged fatigue among workers. An overview of findings from the Maastricht Cohort Study]. / Etiologie van langdurige vermoeidheid onder werknemers. Overzicht van bevindingen uit de Maastrichtse Cohort Studie.

BACKGROUND: Considerable attention is being given to prolonged fatigue among workers because it occurs so frequently and is alleged to have serious consequences. AIM: To present an overview of the magnitude, causes and consequences of prolonged fatigue in the workplace with a view to preventing its occurrence. METHOD: On the basis of of the articles written as part of the Maastricht Cohort Study we present an overview of this study, a prospective cohort study (n=12,140) that covered a period of 4 years. results Prolonged fatigue seems to occur frequently among workers. Risk factors in the aetiology of prolonged fatigue were found in subjective and objective work-related factors, as well as in factors related to the health and private situation of the employee. CONCLUSION: The assumed multifactorial aetiology of prolonged fatigue was confirmed by means of prospective analyses in the Maastricht Cohort Study. The observed risk factors can be applied as tools for the development of effective preventive measures against prolonged fatigue.

[Course, consequences and treatment of prolonged fatigue among workers: an overview of findings from the Maastricht Cohort Study]. / Beloop, consequenties en behandeling van langdurige vermoeidheid onder werknemers. Overzicht van bevindingen uit de Maastrichtse Cohort Studie.

UNLABELLED: summary background Although prolonged fatigue is a common complaint among workers, relatively little is known about its course and consequences. AIM: To present an overview of the course, consequences and treatment of prolonged fatigue in the work force. METHOD: We present an overview of the findings from the Maastricht Cohort Study, which was a prospective cohort (n=12.140) that covered a period of 4 years. results Fatigue runs an unfavourable course. In many workers symptoms of fatigue are present for a long time, and in some workers the symptoms even develop into those of chronic fatigue syndrome. The consequences of prolonged fatigue are also serious and are manifested in various ways: sick leave, work disability, accidents, immunological effects and reduction in work participation. A brief cognitive behaviour therapy administered by general practitioners to employees with prolonged fatigue proved ineffective. CONCLUSION: The severe consequences of prolonged fatigue and the current lack of effective therapies underline the importance of preventing the development of fatigue complaints, for which the Maastricht Cohort Study may provide the basic tools.

Work-family conflict as a risk factor for sickness absence.

OBJECTIVES: (1) To study both cross-sectional and prospective relationships between work-family conflict and sickness absence from work; (2) to explore the direction of the relationships between the different types of conflict (work-home interference and home-work interference) and sickness absence; and (3) to explore gender differences in the above relationships. METHODS: Data from the Maastricht Cohort Study were used with six months of follow up (5072 men and 1015 women at T6). Work-family conflict was measured with the Survey Work-Home Interference Nijmegen (SWING). Sickness absence was assessed objectively through individual record linkage with the company registers on sickness absence. RESULTS: In the cross-sectional analyses, high levels of work-family conflict, work-home interference, and home-work interference were all associated with a higher odds of being absent at the time of completing the questionnaire, after controlling for age and long term disease. Differences in average number of absent days between cases and non-cases of work-home interference were significant for men and most pronounced in women, where the average number of absent days over six months follow up was almost four days higher in women with high versus low-medium work-home interference. CONCLUSIONS: A clear relation between work-family conflict and sickness absence was shown. Additionally, the direction of work-family conflict was associated with a different sickness absence pattern. Sickness absence should be added to the list of adverse outcomes for employees struggling to combine their work and family life.

Work schedules and fatigue: a prospective cohort study.

AIMS: (1) To describe the prevalence of fatigue among employees in different work schedules (day work, three-shift, five-shift, and irregular shift work); (2) to investigate whether different work schedules are related to increasing fatigue over time, while taking into account job title and job characteristics; and (3) to study fatigue among shift workers changing to day work. METHODS: Data from nine consecutive four-monthly self administered questionnaires from the Maastricht Cohort Study on Fatigue at work (n = 12 095) were used with 32 months of follow up. Day and shift workers were matched on job title. RESULTS: The prevalence of fatigue was 18.1% in day workers, 28.6% in three-shift, 23.7% in five-shift, and 19.1% in irregular shift workers. For three-shift and five-shift workers substantial higher fatigue levels were observed compared to day workers at baseline measurement. In the course of fatigue over the 32 months of follow up there were only small and insignificant differences between employees in different work schedules. However, among employees fatigued at baseline, fatigue levels decreased faster over time among five-shift workers compared to fatigued day workers. Shift workers changing to day work reported substantially higher fatigue levels prior to change, compared to those remaining in shift work. CONCLUSIONS: Substantial differences in fatigue existed between day and shift workers. However, as no considerable differences in the course of fatigue were found, these differences have probably developed within a limited time span after starting in a shift work job. Further, evidence was found that fatigue could be an important reason for quitting shift work and moving to day work. Finally, in the relation between work schedules and fatigue, perceived job characteristics might play an important role.