Metabolic syndrome and poor self-rated health as risk factors for premature employment exit: a longitudinal study among 55 016 middle-aged and older workers from the Lifelines Cohort Study and Biobank

BACKGROUND

Poor self-rated health (SRH) is a well-established risk factor for premature employment exit through unemployment, work disability, and early retirement. However, it is unclear whether the premature employment exit risk associated with underlying cardio-metabolic health conditions is fully captured by poor SRH. This study examines the metabolic syndrome (MetS), an early-stage risk factor for cardiovascular disease and type two diabetes mellitus, as a risk factor for premature employment exit while controlling for poor SRH.

METHODS

We analyzed data from N = 55 016 Dutch workers (40-64 years) from five waves of the Lifelines Cohort Study and Biobank. MetS components were based on physical measures, blood markers, and medication use. SRH and employment states were self-reported. The associations between MetS, SRH, and premature employment exit types were analyzed using competing risk regression analysis.

RESULTS

During 4.3 years of follow-up, MetS remained an independent risk factor for unemployment [adjusted subdistribution hazard ratio (SHR): 1.14, 95% CI: 1.03, 1.25] and work disability (adjusted SHR: 1.33, 95% CI: 1.11, 1.58) when adjusted for poor SRH, common chronic diseases related to labor market participation (i.e., cancer, musculoskeletal-, pulmonary-, and psychiatric diseases), and sociodemographic factors. MetS was not associated with early retirement.

CONCLUSIONS

Poor SRH did not fully capture the risk for unemployment and work disability associated with MetS. More awareness about MetS as a 'hidden' cardio-metabolic risk factor for premature employment exit is needed among workers, employers, and occupational health professionals. Regular health check-ups including MetS assessment and MetS prevention might help to prolong healthy working lives.

Effects of changes in residential fast-food outlet exposure on Body Mass Index change: longitudinal evidence from 92,211 Lifelines participants

BACKGROUND

Evidence on the association between fast-food outlet exposure and Body Mass Index (BMI) remains inconsistent and is primarily based on cross-sectional studies. We investigated the associations between changes in fast-food outlet exposure and BMI changes, and to what extent these associations are moderated by age and fast-food outlet exposure at baseline.

METHODS

We used 4-year longitudinal data of the Lifelines adult cohort (N = 92,211). Participant residential addresses at baseline and follow-up were linked to a register containing fast-food outlet locations using geocoding. Change in fast-food outlet exposure was defined as the number of fast-food outlets within 1 km of the residential address at follow-up minus the number of fast-food outlets within 1 km of the residential address at baseline. BMI was calculated based on objectively measured weight and height. Fixed effects analyses were performed adjusting for changes in covariates and potential confounders. Exposure-moderator interactions were tested and stratified analyses were performed if p < 0.10.

RESULTS

Participants who had an increase in the number of fast-food outlets within 1 km had a greater BMI increase (B(95% CI): 0.003 (0.001,0.006)). Decreases in fast-food outlet exposure were not associated with BMI change (B(95% CI): 0.001 (-0.001,0.004)). No clear moderation pattern by age or fast-food outlet exposure at baseline was found.

CONCLUSIONS

Increases in residential fast-food outlet exposure are associated with BMI gain, whereas decreases in fast-food outlet exposure are not associated with BMI loss. Effect sizes of increases in fast-food outlet exposure on BMI change were small at individual level. However, a longer follow-up period may have been needed to fully capture the impact of increases in fast-food outlet exposure on BMI change. Furthermore, these effect sizes could still be important at population level considering the rapid rise of fast-food outlets across society. Future studies should investigate the mechanisms and changes in consumer behaviours underlying associations between changes in fast-food outlet exposure and BMI change.

Symptom profiles and their risk factors in patients with post-COVID-19 condition: a Dutch longitudinal cohort study

BACKGROUND

To improve research and care for patients with post-COVID-19 condition more insight into different subtypes of post-COVID-19 condition and their risk factors is urgently needed. We aimed to identify risk factors of post-COVID-19 condition in general and for specific symptom profiles.

METHODS

This study is based on data collected within the Lifelines Coronavirus disease 2019 (COVID-19) cohort (N = 76 503). Mean pre- and post-SARS-CoV-2 infection symptom scores were compared to classify post-COVID-19 condition. Latent Profile Analysis was used to identify symptom profiles. Logistic and multinomial regression analyses were used to examine the association between demographic, lifestyle and health-related risk factors and post-COVID-19 condition, and symptom profiles, respectively.

RESULTS

Of the 3465 participants having had COVID-19, 18.5% (n = 642) classified for post-COVID-19 condition. Four symptom profiles were identified: muscle pain, fatigue, cardiorespiratory and ageusia/anosmia. Female sex was a risk factor for the muscle pain and fatigue profiles. Being overweight or obese increased risk for all profiles, except the fatigue profile. Having a chronic disease increased the risk for all profiles except the ageusia/anosmia profile, with the cardiorespiratory profile being only significant in case of multimorbidity. Being unvaccinated increased risk of the ageusia/anosmia profile.

CONCLUSIONS

Findings from this study suggest that Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may trigger different pathophysiological mechanisms that may result in different subtypes of post-COVID-19 condition. These subtypes have shared and unique risk factors. Further characterization of symptom profiles and quantification of the individual and societal impact of specific symptom profiles are pressing challenges for future research.

Establishing General Working Population Norms for the Cognitive Symptom Checklist-Work

PURPOSE

The Cognitive Symptom Checklist-Work (CSC-W) is a self-report measure to assess cognitive symptoms (i.e., memory and executive function) in working adults with cancer. To date, general working population norm data are lacking worldwide. We established CSC-W norm values in the general working population, and assessed associations of CSC-W scores with work and health-related factors.

METHODS

This cross-sectional study consisted of 1,000 Dutch working adults, of whom data was collected through an online respondent panel. The sample was stratified for sex and age, and data were weighted. Summary scores of the CSC-W total scale, and memory and executive function symptoms subscales, were determined (e.g., means, percentiles). Z- and T-scores were calculated, and analysis of (co)variance has been applied.

RESULTS

Cognitive symptom scores were relatively stable across age groups, but 18-39-year-old respondents reported lower memory and executive function than respondents in other age groups. Symptom scores of memory function (mean 29.1; SD = 16.7) were higher for all age groups and in both sexes compared to executive function (mean 22.1; SD = 16.8). No sex differences in memory and executive function were observed. Higher symptom scores were associated with performing non-manual work only, manual work only, self-reported long-term illness, and higher levels of depressive symptoms and fatigue.

CONCLUSION

The CSC-W norms may enhance the interpretation and facilitate the analysis of self-reported cognitive symptoms in patients with cancer at work. Our findings may support health care professionals in identifying working adults with cancer with cognitive symptoms and in developing personalized treatment.

Metabolic syndrome increases the risk for premature employment exit: A longitudinal study among 60 427 middle-aged and older workers from the Lifelines Cohort Study and Biobank

OBJECTIVES

This study aimed to examine whether (i) metabolic syndrome (MetS) increases the risk for premature employment exit and (ii) a dose-response relationship exists between an increasing number of MetS components and premature employment exit among middle-aged and older workers.

METHODS

A sample of N=60 427 Dutch workers (40-64 years old) from the Lifelines Cohort Study and Biobank were examined using data from five measurement waves during a total median follow-up time of 4.2 years. MetS components were based on physical measures, blood markers, and medication use. Premature employment exit types (ie, unemployment, work disability, and early retirement) were determined using questionnaires. MetS and number of MetS components were examined as risk factors for premature employment exit using competing risk regression analysis.

RESULTS

MetS significantly increased the risk for work disability [adjusted sub distribution hazard ratio (SHR) 1.78, 95% confidence interval (CI) 1.54-2.05] and unemployment (adjusted SHR 1.16, 95% CI 1.06-1.26). A clear dose-response relationship was found for an increasing number of MetS components and work disability. No associations were found between MetS (components) and early retirement after adjusting for sociodemographic factors.

CONCLUSIONS

MetS was identified as a modifiable early-stage cardio-metabolic risk factor especially for work disability and, to a lesser extent, for unemployment. Further, a clear dose-response relationship was found between an increasing number of MetS components and work disability. MetS interventions and prevention might help to prolong working lives. More awareness is needed among employers and occupational health professionals about the premature employment exit risk faced by middle-aged and older workers with MetS.

Time to return to work by occupational class after total hip or knee arthroplasty

Aims

For the increasing number of working-age patients undergoing total hip or total knee arthroplasty (THA/TKA), return to work (RTW) after surgery is crucial. We investigated the association between occupational class and time to RTW after THA or TKA.

Methods

Data from the prospective multicentre Longitudinal Leiden Orthopaedics Outcomes of Osteoarthritis Study were used. Questionnaires were completed preoperatively and six and 12 months postoperatively. Time to RTW was defined as days from surgery until RTW (full or partial). Occupational class was preoperatively assessed and categorized into four categories according to the International Standard Classification of Occupations 2008 (blue-/white-collar, high-/low-skilled). Cox regression analyses were conducted separately for THA and TKA patients. Low-skilled blue-collar work was used as the reference category.

Results

A total of 360 THA and 276 TKA patients, preoperatively employed, were included. Patients were mainly high-skilled (THA 57%; TKA 41%) or low-skilled (THA 24%; TKA 38%) white-collar workers. Six months post-THA, RTW rates were 78% of low-skilled blue-collar workers compared to 83% to 86% within other occupational classes, increasing after 12 months to 87% to 90% in all occupational classes. Six months post-TKA, RTW rates were 58% of low-skilled and 64% of high-skilled blue-collar workers compared to 80% to 89% of white-collar workers, and after 12 months 79% of low-skilled blue-collar workers compared to 87% to 92% within other occupational classes. High-skilled white-collar workers (THA: hazard ratio (HR) 2.12 (95% confidence interval (CI) 1.32 to 3.40); TKA: HR 2.31 (95% CI 1.34 to 4.00)) and low-skilled white-collar workers (TKA: HR 1.82 (95% CI 1.04 to 3.18)) had a higher hazard to RTW within six months postoperatively.

Conclusion

Clear differences existed in time to RTW among both THA and TKA patients in each of the groups studied. These findings may help guide tailored patient-specific information during preoperative consultation and advice postoperatively, as well as to create awareness among workers and their employers.

Fast-food environments and BMI changes in the Dutch adult general population: the Lifelines cohort

OBJECTIVE

This study investigated cross-sectional and longitudinal associations of fast-food outlet exposure with BMI and BMI change, as well as moderation by age and genetic predisposition.

METHODS

This study used Lifelines' baseline (n = 141,973) and 4-year follow-up (n = 103,050) data. Participant residential addresses were linked to a register with fast-food outlet locations (Nationwide Information System of Workplaces [Dutch: Landelijk Informatiesysteem van Arbeidsplaatsen, LISA]) using geocoding, and the number of fast-food outlets within 1 km was computed. BMI was measured objectively. A weighted BMI genetic risk score was computed, representing overall genetic predisposition toward elevated BMI, based on 941 single-nucleotide polymorphisms genome-wide significantly associated with BMI for a subsample with genetic data (BMI: n = 44,996; BMI change: n = 36,684). Multivariable multilevel linear regression analyses and exposure-moderator interactions were tested.

RESULTS

Participants with ≥1 fast-food outlet within 1 km had a higher BMI (B [95% CI]: 0.17 [0.09 to 0.25]), and those with ≥2 fast-food outlets within 1 km increased more in BMI (B [95% CI]: 0.06 [0.02 to 0.09]) than participants with no fast-food outlets within 1 km. Effect sizes on baseline BMI were largest among young adults (age 18-29 years; B [95% CI]: 0.35 [0.10 to 0.59]) and especially young adults with a medium (B [95% CI]: 0.57 [-0.02 to 1.16]) or high genetic risk score (B [95% CI]: 0.46 [-0.24 to 1.16]).

CONCLUSIONS

Fast-food outlet exposure was identified as a potentially important determinant of BMI and BMI change. Young adults, especially those with a medium or high genetic predisposition, had a higher BMI when exposed to fast-food outlets.

Trajectories of cognitive symptoms and associated factors in cancer survivors after return to work: an 18-month longitudinal cohort study

PURPOSE

Cognitive symptoms affect cancer survivors' functioning at work. To date, cognitive symptoms trajectories in working cancer survivors and the factors associated with these trajectories have not been examined.

METHODS

Data from a heterogeneous group of working cancer survivors (n = 379) of the longitudinal "Work-Life-after-Cancer" study, linked with Netherlands Cancer Registry data, were used. The Cognitive Symptom Checklist-Work was administered at baseline (within the first 3 months after return to work), 6-, 12-, and 18-month follow-up to measure self-perceived memory and executive function symptoms. Data were analyzed using group-based trajectory modeling.

RESULTS

Four trajectories of memory and executive function symptoms were identified. All memory symptoms trajectories were stable and labeled as "stable-high" (15.3% of the sample), "stable-moderately high" (39.6%), "stable-moderately low" (32.0%), and "stable-low" (13.0%). Executive function symptoms trajectories changed over time and were labeled as "increasing-high" (10.1%), "stable-moderately high" (32.0%), "decreasing-moderately low" (35.5%), and "stable-low" (22.4%). Higher symptoms trajectories were associated with older age, longer time from diagnosis to return to work, more quantitative work demands, and higher levels of depressive symptoms at baseline.

CONCLUSIONS

In cancer survivors who returned to work, four cognitive symptoms trajectory subgroups were identified, representing different but relatively stable severity levels of cognitive symptoms.

IMPLICATIONS FOR CANCER SURVIVORS

To identify cancer survivors with higher symptoms trajectories, health care providers should assess cognitive symptoms at baseline after return to work. In case of cognitive symptoms, it is important to also screen for psychological factors to provide appropriate guidance.

Do influence at work and possibilities for development mitigate the impact of job demands for workers with and without depression

OBJECTIVE

Jobs characterized by low job demands and high job resources are associated with better work outcomes, yet it remains unclear whether this is the case for workers with depression. This study examined whether depression moderates the relationship between job demands, job resources, and maintaining employment.

METHODS

Data from the longitudinal population-based Lifelines cohort study were matched with register data on employment from Statistics Netherlands (N=55 950). Job demands included quantitative demands and work pace; job resources included influence at work and possibilities for development. The two-way interaction between job demands and depression and the three-way interaction between job demands, job resources and depression were examined in a zero-inflated Poisson regression model with path 1, including a binary employment outcome, and path 2, a count variable including months out of employment.

RESULTS

The interaction effect of job demands and depression on being employed was significant [b=-0.22, 95% confidence interval (CI) -0.44‒0.01]. Workers without depression were more likely to be employed whereas workers with depression were less likely to be employed if they had high job demands. The three-way interaction between job demands, job resources, and depression was significant for months out of employment (b=0.15, 95% CI 0.01‒0.29), indicating that workers with depression had more months out of employment when reporting high job demands and high job resources compared to workers without depression. Discussion Although increasing influence at work and possibilities for development to prevent negative work outcomes may be beneficial for workers without depression, this approach might be limited for workers with depression.

Neighborhood socioeconomic differences in BMI: The role of fast-food outlets and physical activity facilities

OBJECTIVE

The goal of this study was to investigate the association between neighborhood socioeconomic status (NSES) and BMI and to what extent this association is moderated by availability of fast-food (FF) outlets and pay-for-use physical activity (PA) facilities.

METHODS

Baseline data of adults in Lifelines (N = 146,629) were linked to Statistics Netherlands and a register using geocoding to compute, respectively, NSES (i.e., low, middle, high) and the number of FF outlets and PA facilities within 1 km of the residential address. Multivariable multilevel linear regression analyses were performed to examine the association between NSES and BMI. Two-way and three-way interaction terms were tested to examine moderation by FF outlets and PA facilities.

RESULTS

Participants living in low NSES areas had a higher BMI than participants living in high (B [95% CI]: 0.76 [0.65 to 0.87]) or middle NSES areas (B [95% CI]: 0.40 [0.28 to 0.51]), independent of individual socioeconomic status. Although two- and three-way interactions between NSES, FF outlets, and PA facilities were significant, stratified analyses did not show consistent moderation patterns.

CONCLUSIONS

People living in lower NSES areas had a higher BMI, independent of their individual socioeconomic status. The study found no clear moderation of FF outlets and PA facilities. Environmental factors that may mitigate NSES differences in BMI should be the subject of future research.

Persistence of somatic symptoms after COVID-19 in the Netherlands: an observational cohort study

BACKGROUND

Patients often report various symptoms after recovery from acute COVID-19. Previous studies on post-COVID-19 condition have not corrected for the prevalence and severity of these common symptoms before COVID-19 and in populations without SARS-CoV-2 infection. We aimed to analyse the nature, prevalence, and severity of long-term symptoms related to COVID-19, while correcting for symptoms present before SARS-CoV-2 infection and controlling for the symptom dynamics in the population without infection.

METHODS

This study is based on data collected within Lifelines, a multidisciplinary, prospective, population-based, observational cohort study examining the health and health-related behaviours of people living in the north of the Netherlands. All Lifelines participants aged 18 years or older received invitations to digital COVID-19 questionnaires. Longitudinal dynamics of 23 somatic symptoms surrounding COVID-19 diagnoses (due to SARS-CoV-2 alpha [B.1.1.7] variant or previous variants) were assessed using 24 repeated measurements between March 31, 2020, and Aug 2, 2021. Participants with COVID-19 (a positive SARS-CoV-2 test or a physician's diagnosis of COVID-19) were matched by age, sex, and time to COVID-19-negative controls. We recorded symptom severity before and after COVID-19 in participants with COVID-19 and compared that with matched controls.

FINDINGS

76 422 participants (mean age 53·7 years [SD 12·9], 46 329 [60·8%] were female) completed a total of 883 973 questionnaires. Of these, 4231 (5·5%) participants had COVID-19 and were matched to 8462 controls. Persistent symptoms in COVID-19-positive participants at 90-150 days after COVID-19 compared with before COVID-19 and compared with matched controls included chest pain, difficulties with breathing, pain when breathing, painful muscles, ageusia or anosmia, tingling extremities, lump in throat, feeling hot and cold alternately, heavy arms or legs, and general tiredness. In 12·7% of patients, these symptoms could be attributed to COVID-19, as 381 (21·4%) of 1782 COVID-19-positive participants versus 361 (8·7%) of 4130 COVID-19-negative controls had at least one of these core symptoms substantially increased to at least moderate severity at 90-150 days after COVID-19 diagnosis or matched timepoint.

INTERPRETATION

To our knowledge, this is the first study to report the nature and prevalence of post-COVID-19 condition, while correcting for individual symptoms present before COVID-19 and the symptom dynamics in the population without SARS-CoV-2 infection during the pandemic. Further research that distinguishes potential mechanisms driving post-COVID-19-related symptomatology is required.

FUNDING

ZonMw; Dutch Ministry of Health, Welfare, and Sport; Dutch Ministry of Economic Affairs; University Medical Center Groningen, University of Groningen; Provinces of Drenthe, Friesland, and Groningen.

Mediators of the association between educational attainment and type 2 diabetes mellitus: a two-step multivariable Mendelian randomisation study

AIMS/HYPOTHESIS

Type 2 diabetes mellitus is a major health burden disproportionately affecting those with lower educational attainment (EA). We aimed to obtain causal estimates of the association between EA and type 2 diabetes and to quantify mediating effects of known modifiable risk factors.

METHODS

We applied two-step, two-sample multivariable Mendelian randomisation (MR) techniques using SNPs as genetic instruments for exposure and mediators, thereby minimising bias due to confounding and reverse causation. We leveraged summary data on genome-wide association studies for EA, proposed mediators (i.e. BMI, blood pressure, smoking, television watching) and type 2 diabetes. The total effect of EA on type 2 diabetes was decomposed into a direct effect and indirect effects through multiple mediators. Additionally, traditional mediation analysis was performed in a subset of the National Health and Nutrition Examination Survey 2013-2014.

RESULTS

EA was inversely associated with type 2 diabetes (OR 0.53 for each 4.2 years of schooling; 95% CI 0.49, 0.56). Individually, the largest contributors were BMI (51.18% mediation; 95% CI 46.39%, 55.98%) and television watching (50.79% mediation; 95% CI 19.42%, 82.15%). Combined, the mediators explained 83.93% (95% CI 70.51%, 96.78%) of the EA-type 2 diabetes association. Traditional analysis yielded smaller effects but showed consistent direction and priority ranking of mediators.

CONCLUSIONS/INTERPRETATION

These results support a potentially causal protective effect of EA against type 2 diabetes, with considerable mediation by a number of modifiable risk factors. Interventions on these factors thus have the potential of substantially reducing the burden of type 2 diabetes attributable to low EA.

The association between the presence of fast-food outlets and BMI: the role of neighbourhood socio-economic status, healthy food outlets, and dietary factors

Background

Evidence on the association between the presence of fast-food outlets and Body Mass Index (BMI) is inconsistent. Furthermore, mechanisms underlying the fast-food outlet presence-BMI association are understudied. We investigated the association between the number of fast-food outlets being present and objectively measured BMI. Moreover, we investigated to what extent this association was moderated by neighbourhood socio-economic status (NSES) and healthy food outlets. Additionally, we investigated mediation by frequency of fast-food consumption and amount of fat intake.

Methods

In this cross-sectional study, we used baseline data of adults in Lifelines (N = 149,617). Geo-coded residential addresses were linked to fast-food and healthy food outlet locations. We computed the number of fast-food and healthy food outlets within 1 kilometre (km) of participants’ residential addresses (each categorised into null, one, or at least two). Participants underwent objective BMI measurements. We linked data to Statistics Netherlands to compute NSES. Frequency of fast-food consumption and amount of fat intake were measured through questionnaires in Lifelines. Multivariable multilevel linear regression analyses were performed to investigate associations between fast-food outlet presence and BMI, adjusting for individual and environmental potential confounders. When exposure-moderator interactions had p-value < 0.10 or improved model fit (∆AIC ≥ 2), we conducted stratified analyses. We used causal mediation methods to assess mediation.

Results

Participants with one fast-food outlet within 1 km had a higher BMI than participants with no fast-food outlet within 1 km (B = 0.11, 95% CI: 0.01, 0.21). Effect sizes for at least two fast-food outlets were larger in low NSES areas (B = 0.29, 95% CI: 0.01, 0.57), and especially in low NSES areas where at least two healthy food outlets within 1 km were available (B = 0.75, 95% CI: 0.19, 1.31). Amount of fat intake, but not frequency of fast-food consumption, explained this association for 3.1%.

Conclusions

Participants living in low SES neighbourhoods with at least two fast-food outlets within 1 km of their residential address had a higher BMI than their peers with no fast-food outlets within 1 km. Among these participants, healthy food outlets did not buffer the potentially unhealthy impact of fast-food outlets. Amount of fat intake partly explained this association. This study highlights neighbourhood socio-economic inequalities regarding fast-food outlets and BMI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-13826-1.

Do chronic diseases moderate the association between psychosocial working conditions and work exit? Longitudinal results from 55 950 Dutch workers

BACKGROUND

This study aims to examine whether the presence of chronic diseases or multimorbidity moderates the associations between psychosocial working conditions and work exit through unemployment, work disability or early retirement.

METHODS

Data from Lifelines (n=55 950), a prospective population-based cohort study, were enriched with monthly information on employment status from Statistics Netherlands. Working conditions were measured with the Copenhagen Psychosocial Questionnaire. Work exit was defined as unemployment, work disability and early retirement. Participants were classified as having no chronic disease, one chronic disease or multimorbidity. Cause-specific Cox proportional hazard regression models, adjusted for age, gender, education and partnership status, were used to analyse associations between working conditions and work exit. Interaction terms were used to examine moderation by chronic disease status.

RESULTS

Higher social support decreased the risk for unemployment, work disability and early retirement. Higher meaning of work decreased the risk of unemployment, and more possibilities for development decreased the risk for work disability. Chronic disease status did generally not moderate associations between working conditions and work exit. Only among workers without a chronic disease, more possibilities for development was associated with a lower risk for unemployment (HR: 0.89; 95% CI: 0.85 to 0.94).

CONCLUSION

While efforts to retain workers with chronic diseases in the labour market should continue, favourable psychosocial working conditions are important for all workers.

Transitioning out of work and metabolic syndrome incidence: a longitudinal study among 13 303 older workers from the Lifelines Cohort Study and Biobank

BACKGROUND

This study investigates (1) whether different employment transition types (ie, unemployment, work disability, early retirement and regular retirement) are associated with metabolic syndrome (MetS) incidence among older workers (50-64 years) and (2) whether occupational group moderates the association between employment transition type and MetS incidence.

METHODS

A sample of 13 303 older Dutch workers from the Lifelines Cohort Study and Biobank was examined using longitudinal data from two comprehensive measurement waves with a mean follow-up time of 3.7 years. MetS components were based on physical measures, blood markers and medication use. Employment transitions were determined using questionnaires. Logistic regression analysis was performed to examine the association between employment transition type and MetS incidence.

RESULTS

Older workers who transitioned from employment to unemployment (adjusted OR 1.39, 95% CI 1.05 to 1.82) or work disability (adjusted OR 1.89, 95% CI 1.15 to 3.10) had a significantly higher MetS incidence than the working control group. No association between early retirement or regular retirement with MetS incidence was found after adjusting for sociodemographic, educational and occupational factors. Occupational group did not moderate the association between employment transition type and MetS incidence.

CONCLUSION

The results suggest that older workers who transition from employment to unemployment or work disability are at risk for developing MetS. More awareness among occupational physicians and general practitioners about MetS incidence in late working life is needed in general and more specific among older workers who transition into unemployment or work disability.

Development and validation of a prediction model for unemployment and work disability among 55 950 Dutch workers

Background

This study developed prediction models for involuntary exit from paid employment through unemployment and disability benefits and examined if predictors and discriminative ability of these models differ between five common chronic diseases.

Methods

Data from workers in the Lifelines Cohort Study (n = 55 950) were enriched with monthly information on employment status from Statistics Netherlands. Potential predictors included sociodemographic factors, chronic diseases, unhealthy behaviours and working conditions. Data were analyzed using cause-specific Cox regression analyses. Models were evaluated with the C-index and the positive and negative predictive values (PPV and NPV, respectively). The developed models were externally validated using data from the Study on Transitions in Employment, Ability and Motivation.

Results

Being female, low education, depression, smoking, obesity, low development possibilities and low social support were predictors of unemployment and disability. Low meaning of work and low physical activity increased the risk for unemployment, while all chronic diseases increased the risk of disability benefits. The discriminative ability of the models of the development and validation cohort were low for unemployment (c = 0.62; c = 0.60) and disability benefits (c = 0.68; c = 0.75). After stratification for specific chronic diseases, the discriminative ability of models predicting disability benefits improved for cardiovascular disease (c = 0.81), chronic obstructive pulmonary disease (c = 0.74) and diabetes mellitus type 2 (c = 0.74). The PPV was low while the NPV was high for all models.

Conclusion

Taking workers’ particular disease into account may contribute to an improved prediction of disability benefits, yet risk factors are better examined at the population level rather than at the individual level.

Multimorbidity and exit from paid employment: the effect of specific combinations of chronic health conditions

Background

This study aimed to assess the association between multimorbidity and exit from paid employment, and which combinations of chronic health conditions (CHCs) have the strongest association with exit from paid employment.

Methods

Data from 111 208 workers aged 18–64 years from Lifelines were enriched with monthly employment data from Statistics Netherlands. Exit from paid employment during follow-up was defined as a change from paid employment to unemployment, disability benefits, economic inactivity or early retirement. CHCs included cardiovascular diseases (CVD), chronic obstructive pulmonary disease (COPD), rheumatoid arthritis (RA), type 2 diabetes (T2DM) and depression. Cox-proportional hazards models were used to examine the impact of multimorbidity and combinations of CHCs on exit from paid employment.

Results

Multimorbidity increased the risk of exiting paid employment compared with workers without CHCs (hazard ratio (HR): 1.52; 95% confidence interval (CI): 1.35–1.71) or one CHC (HR: 1.14; 95% CI: 1.01–1.28). The risk for exit from paid employment increased among workers with COPD if they additionally had CVD (HR: 1.39; 95% CI: 1.03–1.88), depression (HR: 1.46; 95% CI: 1.10–1.93) or RA (HR: 1.44; 95% CI: 1.08–1.91), for workers with T2DM if they additionally had CVD (HR: 1.43; 95% CI: 1.07–1.91) or depression (HR: 2.09; 95% CI: 1.51–2.91) and for workers with depression who also had T2DM (HR: 1.68; 95% CI: 1.21–2.32).

Conclusion

This study showed that workers with multimorbidity, especially having a combination of COPD and depression or T2DM and depression, have a higher risk for early exit from paid employment and, therefore, may need tailored support at the workplace.

The association between fast-food outlet proximity and density and Body Mass Index: Findings from 147,027 Lifelines Cohort Study participants

Unhealthy food environments may contribute to an elevated Body Mass Index (BMI), which is a chronic disease risk factor. We examined the association between residential fast-food outlet exposure, in terms of proximity and density, and BMI in the Dutch adult general population. Additionally, we investigated to what extent this association was modified by urbanisation level. In this cross-sectional study, we linked residential addresses of baseline adult Lifelines Cohort participants (n = 147,027) to fast-food outlet locations using geo-coding. We computed residential fast-food outlet proximity, and density within 500 m, 1, 3, and 5 km. We used stratified (urban versus rural areas) multilevel linear regression models, adjusting for age, sex, partner status, education, employment, neighbourhood deprivation, and address density. The mean BMI of participants was 26.1 (SD 4.3) kg/m². Participants had a mean (SD) age of 44.9 (13.0), 57.3% was female, and 67.0% lived in a rural area. Having two or more (urban areas) or five or more (rural areas) fast-food outlets within 1 km was associated with a higher BMI (B = 0.32, 95% confidence interval (CI): 0.03, 0.62; B = 0.23, 95% CI: 0.10, 0.36, respectively). Participants in urban and rural areas with a fast-food outlet within <250 m had a higher BMI (B = 0.30, 95% CI: 0.03, 0.57; B = 0.20, 95% CI: 0.09, 0.31, respectively). In rural areas, participants also had a higher BMI when having at least one fast-food outlet within 500 m (B = 0.10, 95% CI: 0.02, 0.18). In conclusion, fast-food outlet exposure within 1 km from the residential address was associated with BMI in urban and rural areas. Also, fast-food outlet exposure within 500 m was associated with BMI in rural areas, but not in urban areas. In the future, natural experiments should investigate changes in the fast-food environment over time.

Occupational Differences in Metabolic Syndrome Incidence Among Older Workers

This study investigates whether the incidence of metabolic syndrome (MetS), and its components, differs by occupational group among older workers (45-65 years) and whether health behaviors (smoking, leisure-time physical activity, diet quality) can explain these differences. We analyzed data from older workers (N=23 051) from two comprehensive measurement waves of the Lifelines Cohort Study and Biobank. MetS components were determined by physical measurements, blood markers, medication use, and self-reports. Occupational group and health behaviors were assessed by questionnaires. The association between occupational groups and MetS incidence was examined using Cox regression analysis. Health behaviors were subsequently added to the model to examine whether they can explain differences in MetS incidence between occupational groups. Low skilled white-collar (HR: 1.25, 95% CI: 1.13, 1.39) and low skilled blue-collar (HR: 1.45, 95% CI: 1.25, 1.69) workers had a significantly higher MetS incidence risk during 3.65 years follow-up than high skilled white-collar workers. Health behaviors reduced the strength of the association between occupational group and MetS incidence most among low skilled blue-collar workers (i.e. 10.3% reduction) as unhealthy behaviors were more prevalent in this occupational group. Similar occupational differences were observed on MetS component level. To conclude, MetS incidence in older workers differs between occupational groups and health behaviors only explain a small part of these differences. Health promotion tailored to occupational groups may be beneficial specifically among older low skilled blue-collar workers. Research into other factors that contribute to occupational differences is needed, as well as studies spanning the entire working life course.

Does social support at home moderate the association between social support at work and work functioning among cancer patients?

PURPOSE

The aims of this study were to examine (1) the longitudinal associations of supervisor and colleague social support with work functioning in cancer patients who have returned to work and (2) the moderating role of social support at home.

METHODS

Data from the longitudinal Work Life after Cancer study were used (n = 384). Work functioning (low versus moderate to high work functioning) was measured with the validated Work Role Functioning Questionnaire 2.0. Social support at work was measured from both supervisor and colleagues with the Copenhagen Psychosocial Questionnaire. Social support at home was measured with the Social Support List-Discrepancies. Logistic generalized estimating equations were used to analyse associations between supervisor and colleague social support and work functioning, and to examine the possible moderating effect of social support at home.

RESULTS

More supervisor (OR: 1.21; 95% CI: 1.10, 1.32) and colleague (1.13; 1.03, 1.24) social support were significantly associated with moderate to high work functioning. The association between colleague social support and work functioning was attenuated for those who did not experience enough social support at home but remained almost significant for supervisor social support (1.17; 1.00, 1.37).

CONCLUSIONS

Supervisor social support is associated with better work functioning regardless of social support at home, while colleague social support is only associated with better work functioning when cancer patients experience enough social support at home.

IMPLICATIONS FOR CANCER SURVIVORS

Occupational physicians may play a key role in creating awareness that social support at work and at home are beneficial for cancer patients' work functioning.

Process evaluation of a complex workplace intervention to prevent musculoskeletal pain in nursing staff: results from INTEVAL_Spain

Background

INTEVAL_Spain was a complex workplace intervention to prevent and manage musculoskeletal pain among nursing staff. Process evaluations can be especially useful for complex and multifaceted interventions through identifying the success or failure factors of an intervention to improve the intervention implementation.

Objectives

This study performed a process evaluation of INTEVAL_Spain and aimed to examine whether the intervention was conducted according to the protocol, to investigate the fulfilment of expectations and the satisfaction of workers.

Methods

The intervention was a two-armed cluster randomized controlled trial and lasted 1 year. The process evaluation included quantitative and qualitative methods. Quantitative methods were used to address the indicators of Steckler and Linnan’s framework. Data on recruitment was collected through a baseline questionnaire for the intervention and the control group. Reach and dose received were collected through participation sheets, dose delivered and fidelity through internal registries, and fulfilment of expectations and satisfaction were collected with two questions at 12-months follow-up. Qualitative methods were used for a content analysis of discussion groups at the end of the intervention led by an external moderator to explore satisfaction and recommendations. The general communication and activities were discussed, and final recommendations were agreed on. Data were synthesized and results were reported thematically.

Results

The study was performed in two Spanish hospitals during 2016-2017 and 257 workers participated. Recruitment was 62 and 51% for the intervention and the control group, respectively. The reach of the activities ranged from 96% for participatory ergonomics to 5% for healthy diet. The number of sessions offered ranged from 60 sessions for Nordic walking to one session for healthy diet. Fidelity of workers ranged from 100% for healthy diet and 79% for participatory ergonomics, to 42 and 39% for Nordic walking and case management, respectively. Lowest fidelity of providers was 75% for case management and 82% for Nordic walking. Fulfilment of expectations and satisfaction ranged from 6.6/10 and 7.6/10, respectively, for case management to 10/10 together for the healthy diet session. Discussion groups revealed several limitations for most of the activities, mainly focused on a lack of communication between the Champion (coordinator) and the workers.

Conclusions

This process evaluation showed that the implementation of INTEVAL_Spain was predominantly carried out as intended. Process indicators differed depending on the activity. Several recommendations to improve the intervention implementation process are proposed.

Trial registration

ISRCTN15780649.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12912-021-00716-x.

Associations of Genetic Factors, Educational Attainment, and Their Interaction With Kidney Function Outcomes

Both genetic predisposition and low educational attainment (EA) are associated with higher risk of chronic kidney disease. We examined the interaction of EA and genetic risk in kidney function outcomes. We included 3,597 participants from the Prevention of Renal and Vascular End-Stage Disease Cohort Study, a longitudinal study in a community-based sample from Groningen, the Netherlands (median follow-up, 11 years; 1997–2012). Kidney function was approximated by obtaining estimated glomerular filtration rate (eGFR) from serum creatinine and cystatin C. Individual longitudinal linear eGFR trajectories were derived from linear mixed models. Genotype data on 63 single-nucleotide polymorphisms, with known associations with eGFR, were used to calculate an allele-weighted genetic score (WGS). EA was categorized into high, medium, and low. In ordinary least squares analysis, higher WGS and lower EA showed additive effects on reduced baseline eGFR; the interaction term was nonsignificant. In analysis of eGFR decline, the significant interaction term suggested amplification of genetic risk by low EA. Adjustment for known renal risk factors did not affect our results. This study presents the first evidence of gene-environment interaction between EA and a WGS for eGFR decline and provides population-level insights into the mechanisms underlying socioeconomic disparities in chronic kidney disease.

Depressive Symptom Trajectories and Early Adult Education and Employment: Comparing Longitudinal Cohorts in Canada and the United States

Adolescent depressive symptoms are risk factors for lower education and unemployment in early adulthood. This study examines how the course of symptoms from ages 16–25 influences early adult education and employment in Canada and the USA. Using data from the National Longitudinal Survey of Children and Youth (n = 2348) and the National Longitudinal Survey of Youth 79 Child/Young Adult (n = 3961), four trajectories (low-stable; increasing; decreasing; and increasing then decreasing, i.e., mid-peak) were linked to five outcomes (working with a post-secondary degree; a high school degree; no degree; in school; and NEET, i.e., not in employment, education, or training). In both countries, increasing, decreasing, and mid-peak trajectories were associated with higher odds of working with low educational credentials, and/or NEET relative to low-stable trajectories. In Canada, however, all trajectories had a higher predicted probability of either being in school or working with a post-secondary degree than the other outcomes; in the USA, all trajectory groups were most likely to be working with a high school degree. Higher depressive symptom levels at various points between adolescent and adulthood are associated with working with low education and NEET in Canada and the USA, but Canadians are more likely to have better education and employment outcomes.

Geriatric Syndromes and Incident Chronic Health Conditions Among 9094 Older Community-Dwellers: Findings from the Lifelines Cohort Study

OBJECTIVES

To determine the association between geriatric syndromes and any specific incident chronic health conditions among older community-dwellers.

DESIGN

Population-based cohort study over a median follow-up period of 43 months.

SETTING AND PARTICIPANTS

Participants from the Lifelines Cohort Study aged 60 years and older without presence of the studied chronic health conditions at baseline (n = 9094).

METHODS

Baseline assessment took place between November 2006 and December 2013 and included information on socioeconomic (age, sex, level of education and income), social contact, and health-related factors [eg, self-rated health, body mass index, chronic health conditions, and health behavior (alcohol consumption and smoking)]. Participants also reported the presence of geriatric syndromes (ie, included falls, incontinence, vision impairment, hearing impairment, depressive symptoms, and frailty at baseline). Three follow-up questionnaires were used to examine the incidence of any and specific chronic health conditions (ie, pulmonary and cardiovascular diseases, diabetes, cancer, and neurological diseases). Cox regression was used to analyze the longitudinal associations between geriatric syndromes and incident chronic health conditions.

RESULTS

Older community-dwelling individuals with at least one geriatric syndrome (44.7%, n = 4038) had an increased risk of developing any new chronic health condition [hazard ratio (HR) 1.35; 95% confidence interval (CI) 1.21-1.51]. The association was attenuated but remained significant after adjustment for socioeconomic factors, social contact, health status, and health behavior (HR 1.27; 95% CI 1.12-1.43). Analyses for specific chronic health conditions showed that compared with older community-dwellers without geriatric syndromes, those with geriatric syndromes had an increased risk to develop a cardiovascular health condition (HR 1.42; 95% CI 1.13-1.79) or diabetes (HR 1.53; 95% CI 1.11-2.11). They had no increased risk to develop pulmonary conditions, cancer, or neurological conditions.

CONCLUSION AND IMPLICATIONS

The presence of geriatric syndromes is associated with incident chronic health conditions, specifically cardiovascular conditions and diabetes. Increased awareness is needed among older people with geriatric syndromes and their physicians. Comprehensive assessments of geriatric syndromes may help to prevent or at least delay the development of chronic health conditions.

Childhood Socioeconomic Status and Depressive Symptom Trajectories in the Transition to Adulthood in the United States and Canada

PURPOSE

We examined whether young people in the U.S. and Canada exhibit similar depressive symptom trajectories in the transition to adulthood and compared the effect of childhood socioeconomic status on trajectory membership.

METHODS

We used the American National Longitudinal Survey of Youth 1979 Child/Young Adult (n = 6,315) and the Canadian National Longitudinal Survey of Children and Youth (n = 3,666). Depressive symptoms were measured using five items from the Center for Epidemiological Studies on Depression scale. Latent trajectories of depressive symptoms from ages 16-25 years were identified using growth mixture models. We estimated the effect of childhood family income, parental education, and parental unemployment on trajectory membership using multivariable Poisson regression models with robust variances.

RESULTS

We identified four similar trajectories in the two countries: (1) low stable; (2) mid-peak; (3) increasing; and (4) decreasing. Relatively more Americans were in the low-stable trajectory group than Canadians (77.6% vs. 64.9%), and fewer Americans were in the decreasing group (7.1% vs. 19.1%). In the U.S., childhood family income in the bottom two quartiles was related to higher rates of increasing trajectory membership compared with income in the top quartile (incidence rate ratios: 1.59-1.79, p < .05), but not in Canada. In the U.S., parental education at a high school level was associated with higher rates of decreasing trajectory membership compared with higher education (incidence rate ratio = 1.45, confidence interval: 1.10-1.91; p = .01), but not in Canada.

CONCLUSIONS

Depressive symptoms may take a similar course in the transition to adulthood within these two countries. Country differences may modify the degree to which childhood socioeconomic status determines trajectory membership.

Multimorbidity and the Transition Out of Full-Time Paid Employment: A Longitudinal Analysis of the Health and Retirement Study

Objectives

This study aims to examine whether older workers aged 50–64 years with multimorbidity are at increased risk to transition from full-time paid employment to part-time employment, partial retirement, unemployment, disability, economic inactivity, full retirement or die than workers without a chronic health condition and workers with one chronic health condition, and whether socioeconomic position (SEP) modifies these transitions.

Method

Using data from the Health and Retirement Study (1992–2014; n = 10,719), sub-distribution hazard ratios with 95% confidence intervals were calculated with a time-varying Fine and Gray competing-risks survival regression model to examine exit from full-time paid employment. We investigated the modifying effect of SEP by examining its interaction with multimorbidity.

Results

Workers with multimorbidity had a higher risk of transitioning to partial retirement (1.45; 1.22, 1.72), disability (1.84; 1.21, 2.78) and full retirement (1.63; 1.47, 1.81), and they had a higher mortality risk (2.58; 1.71, 3.88) than workers without chronic disorders. Compared to workers with one chronic health condition, workers with multimorbidity had an increased risk for partial (1.19; 1.02, 1.40) and full retirement (1.29; 1.17, 1.42), and mortality (1.49; 1.09, 2.04). Only SEP measured as educational level modified the relationship between multimorbidity and mortality.

Discussion

Workers with multimorbidity seem more prone to leave full-time paid employment than workers without or with one a chronic health condition. Personalized work accommodations may be necessary to help workers with multimorbidity prolong their working life.

The influence of unhealthy behaviours on early exit from paid employment among workers with a chronic disease: A prospective study using the Lifelines cohort

OBJECTIVES

This study examined the risk of unhealthy behaviours and the additive effects of multiple unhealthy behaviours on exit from paid employment among workers with a chronic disease and investigated effect modification by gender and educational level.

METHODS

Data from the Lifelines cohort, collected between 2006 and 2013, were enriched with registry data from Statistics Netherlands with up to 11 years follow-up. Workers with a chronic disease were selected (n = 11,467). The influence of unhealthy behaviours (physical inactivity, smoking, unhealthy diet, high alcohol intake, and obesity) on exit from paid employment (unemployment, disability benefits, early retirement, and economic inactivity) was examined using competing risk models. To examine effect modification by gender and educational level, interaction terms were added.

RESULTS

Smoking and low fruit intake increased the risk to exit paid employment through unemployment and disability benefits. Low vegetable intake increased the risk of unemployment, obesity the risk of receiving disability benefits, and high alcohol intake the risk of early retirement. Physical inactivity was not associated with any exit from paid employment. Having multiple unhealthy behaviours increased the risk of both unemployment and of receiving disability. No consistent effect modification for gender or educational level was found.

CONCLUSIONS

Unhealthy behaviours increased the risk to exit paid employment through unemployment and disability benefits among workers with a chronic disease, and this risk increased when having multiple unhealthy behaviours. Health promotion to support workers with chronic diseases to make healthier choices may help to extend their working life.

Occupational distribution of metabolic syndrome prevalence and incidence differs by sex and is not explained by age and health behavior: results from 75 000 Dutch workers from 40 occupational groups

INTRODUCTION

This study examines the association between 40 occupational groups and prevalence and incidence of metabolic syndrome (MetS), separately for male and female workers, and whether age and health behaviors can explain the association.

RESEARCH DESIGN AND METHODS

Data from 74 857 Lifelines Cohort and Biobank Study participants were used to regress occupational group membership, coded by Statistics Netherlands, on the prevalence and incidence of MetS using logistic and Cox regression analyses. MetS diagnosis was based on physical examinations, blood analysis, and recorded medication use. Information on age, smoking status, physical activity, diet and alcohol consumption was acquired using questionnaires.

RESULTS

Baseline MetS prevalence was 17.5% for males and 10.6% for females. During a median 3.8 years of follow-up, MetS incidence was 7.8% for males and 13.2% for females. One occupational group was associated with an increased MetS risk in both sexes. Six additional occupational groups had an increased risk for MetS among men, four among women. Highest risks were found for male 'stationary plant and machine operators' (HR: 1.94; 95% CI 1.26 to 3.00) and female 'food preparation assistants' (HR: 1.80; 95% CI 1.01 to 3.22).

CONCLUSIONS

Findings suggest that occupational group matters for men and women in MetS development, and that differences in MetS prevalence across occupations are not merely a reflection of selection of metabolically unhealthy workers into specific occupations. The striking sex differences in the occupational distribution of MetS indicate that preventive measures should, with some exceptions, target men and women separately.

Influence of changing working conditions on exit from paid employment among workers with a chronic disease

Objectives

To investigate the relation between changes in working conditions and exit from paid employment among workers with a chronic disease.

Methods

Six waves from the longitudinal Study on Transitions in Employment, Ability and Motivation (2010–2016), enriched with tax-based employment information from Statistics Netherlands (2011–2017), were available for 4820 chronically ill workers aged 45–63 years (mean 55.3 years, SD 5.1). A change in working conditions (physical workload, psychological job demands, job autonomy, emotional job demands and social support) was defined as an increase or decrease between two consecutive waves of at least one SD. Discrete-time survival models with repeated measurements were used to estimate the relative risk (RR) of a change in working conditions on exiting paid employment in the following year compared with no change and consecutive favourable working conditions.

Results

A favourable change in physical workload lowered the risk to exit paid employment (RR 0.46, 95% CI 0.22 to 0.94). An adverse change in psychosocial working conditions, especially a decrease in social support (RR 2.07, 95% CI 1.52 to 2.81), increased the likelihood to exit paid employment. In contrast, a favourable change in psychological job demands increased the risk to exit paid employment (RR 1.57, 95% CI 1.09 to 2.24). Multiple adverse changes increased the risk to exit paid employment up to six times (RR 6.06, 95% CI 2.83 to 12.98).

Conclusions

Changes in working conditions among workers with chronic diseases influence exit from paid employment. Ensuring that working conditions can be adapted to the needs of workers with a chronic disease may help to extend working life.

Multifaceted intervention for the prevention and management of musculoskeletal pain in nursing staff: Results of a cluster randomized controlled trial

BACKGROUND

Nurses and nursing aides are at high risk of developing musculoskeletal pain (MSP). This study aimed to evaluate a multifaceted intervention to prevent and manage MSP in two hospitals.

MATERIAL AND METHODS

We performed a two-armed cluster randomized controlled trial, with a late intervention control group. Clusters were independent hospital units with nursing staff as participants. The intervention comprised three evidence-based components: participatory ergonomics, health promotion activities and case management. Both the intervention and the control group received usual occupational health care. The intervention lasted one year. MSP and work functioning data was collected at baseline, six and 12-month follow-up. Odds ratios (OR) and their 95% confidence intervals (95%CI) were calculated for MSP risk in the intervention group compared to the control group using logistic regression through GEE. Differences in work functioning between the intervention and control group were analyzed using linear regression through GEE. The incidence of sickness absence was calculated through logistic regression and Cox proportional hazard modeling was used to analyze the effect of the intervention on sickness absence duration.

RESULTS

Eight clusters were randomized including 473 nurses and nursing aides. At 12 months, the intervention group showed a statistically significant decrease of the risk in neck, shoulders and upper back pain, compared to the control group (OR = 0.37; 95%CI = 0.14-0.96). A reduction of low back pain was also observed, though non statistically significant. We found no differences regarding work functioning and the incidence and duration of sickness absence.

CONCLUSIONS

The intervention was effective to reduce neck, shoulder and upper back pain. Our results, though modest, suggests that interventions to prevent and manage MSP need a multifactorial approach including the three levels of prevention, and framed within the biopsychosocial model.

Investigating young adults' mental health and early working life trajectories from a life course perspective: the role of transitions

BACKGROUND

Many young adults leave the labour market because of mental health problems or never really enter it, through early moves onto disability benefits. Across many countries of the Organisation for Economic Co-operation and Development, between 30% and 50% of all new disability benefit claims are due to mental health problems; among young adults this moves up to 50%-80%.

OUTLINE

We propose a research agenda focused on transitions in building young adults' mental health and early working life trajectories, considering varying views for subgroups of a society. First, we briefly review five transition characteristics, then we elaborate a research agenda with specific research questions.

RESEARCH AGENDA

Our research agenda focuses on transitions as processes, in time and place and as sensitive periods, when examining young adults' mental health and early working life trajectories from a life course perspective. As more and more childhood and adolescent cohorts mature and facilitate research on later life labour market, work and health outcomes, transition research can help guide policy and practice interventions.

FUTURE CROSS-DISCIPLINARY RESEARCH

In view of the many challenges young adults face when entering the changing world of work and labour markets, future research on transitions in young adults related to their mental health and early working life trajectories will provide ample opportunities for collaborative cross-disciplinary research and stimulate debate on this important challenge.

Correction to: The impact of low education and poor health on unemployment varies by work life stage

During the calculation of the physical component score and the mental component score, the score of the RAND 1 was erroneously coded in the opposite direction. After correcting this mistake, the interaction between low education and poor physical health on unemployment in early work life becomes statistically significant.

SES, Chronic Kidney Disease, and Race in the U.S.: A Systematic Review and Meta-analysis

CONTEXT

The risk of chronic kidney disease (CKD) in the U.S. is higher in individuals with low SES than in those with high SES. However, differences in these risks between African Americans and whites are unclear.

EVIDENCE ACQUISITION

Studies published through August 30, 2016 in Medline and EMBASE were searched. From the seven studies (1,775,267 participants) that met inclusion criteria, association estimates were pooled by race in meta-analysis. The ratio of association estimates and the corresponding 95% CIs for African Americans and whites were also pooled in meta-analysis. Additionally, meta-regression analysis was used to explore whether race is related to the strength of SES-CKD association. The analysis was conducted in September 2016.

EVIDENCE SYNTHESIS

The risk of CKD in low-SES people was 58% higher in African Americans (relative risk=1.58, 95% CI=1.33, 1.84) and 91% higher in whites (relative risk=1.91, 95% CI=1.47, 2.35) compared with their high-SES counterparts. The relative risk of CKD in low SES (versus high SES) was lower in African Americans than in whites (relative risk ratio=0.71, 95% CI=0.65, 0.77). Results from meta-regression analyses also indicated that race is potentially related to the strength of the association between low SES and CKD (p for difference between whites and African Americans=0.001).

CONCLUSIONS

The risk of CKD in low SES (versus high SES) is higher in whites than in African Americans.

The impact of low education and poor health on unemployment varies by work life stage

Objectives

The aim of this study is to examine associations and interactions of education, and physical and mental health with unemployment in early, mid, and late work life.

Methods

This cross-sectional study uses data from 69,118 respondents from Lifelines. Health status was measured with the RAND-36, education was self-reported, and participants working <12 h per week or indicating to be unemployed were considered unemployed. The relative excess risk due to interaction (RERI) was calculated to measure interaction on the additive scale.

Results

Interactions of low education and poor mental health were found in early [RERI: 2.14; 95% confidence interval (CI): 0.63, 3.65], mid (1.41; 0.61, 2.20) and late (0.63; 0.09, 1.17) work life. Interaction between low education and poor physical health was only found in mid-work life (1.27; 0.61, 1.93).

Conclusions

Low education and poor physical and mental health exacerbate each other’s impact on unemployment varying by work life stage. Policies addressing unemployment may become more effective if they better account for the physical and mental health status of adults in certain stages of their work life.

Electronic supplementary material

The online version of this article (doi:10.1007/s00038-017-0972-7) contains supplementary material, which is available to authorized users.

The interaction of socioeconomic position and type 2 diabetes mellitus family history: a cross-sectional analysis of the Lifelines Cohort and Biobank Study

BACKGROUND

Low socioeconomic position (SEP) and family history of type 2 diabetes mellitus (T2DM) contribute to increased T2DM risk, but it is unclear whether they exacerbate each other's effect. This study examined whether SEP reinforces the association of T2DM family history with T2DM, and whether behavioural and clinical risk factors can explain this reinforcement.

METHODS

We used cross-sectional data on 51 725 participants from Lifelines. SEP was measured as educational level and was self-reported, just as family history of T2DM. T2DM was diagnosed based on measured fasting plasma glucose and glycated haemoglobin, combined with self-reported disease and recorded medication use. We assessed interaction on the additive scale by calculating the relative excess risk due to interaction (RERI).

RESULTS

ORs of T2DM were highest for males (4.37; 95% CI 3.47 to 5.51) and females (7.77; 5.71 to 10.56) with the combination of low SEP and a family history of T2DM. The RERIs of low SEP and a family history of T2DM were 0.64 (-0.33 to 1.62) for males and 3.07 (1.53 to 4.60) for females. Adjustment for behavioural and clinical risk factors attenuated associations and interactions, but risks remained increased.

CONCLUSION

Low SEP and family history of T2DM are associated with T2DM, but they also exacerbate each other's impact in females but not in males. Behavioural and clinical risk factors partly explain these gender differences, as well as the associations underlying the interaction in females. The exacerbation by low SEP of T2DM risks in T2DM families deserves attention in prevention and community care.

Active recruitment and limited participant-load related to high participation in large population-based biobank studies

OBJECTIVES

Insight into baseline participation rates and their determinants is crucial for designing future population-based biobank studies. We therefore conducted a systematic review and meta-analysis of baseline participation rates and their determinants in large longitudinal population-based biobank studies.

STUDY DESIGN AND SETTING

We screened studies registered within the Public Population Project in Genomics and Society and in the Biobanking and Biomolecular Resources Research Infrastructure catalogues to find potentially eligible studies. We retrieved data with regard to participation rate, biobank design, performed measurements, and specific strategies for improving participation. We calculated weighted pooled proportions for each determinant using random-effects models.

RESULTS

We included 25 studies (participation rates 5-96%). Participation rates were highest for studies involving face-to-face recruitment [82.6%; 95% confidence interval (CI): 72.2%, 90.9%], for studies in which participants were visited for an examination (77.5%; 95% CI: 64.0%, 88.6%) and for studies in which at maximum four measurements were performed (78.2%; 95% CI: 69.7%, 85.7%). Specific strategies to improve participation were not found to be associated with higher participation rates.

CONCLUSION

Specific choices of recruitment methods and design have consequences for participation rates. These insights may help to increase participation in future studies, thereby enhancing the validity of their findings.

Absolute and Relative Socioeconomic Health Inequalities across Age Groups

Background

The magnitude of socioeconomic health inequalities differs across age groups. It is less clear whether socioeconomic health inequalities differ across age groups by other factors that are known to affect the relation between socioeconomic position and health, like the indicator of socioeconomic position, the health outcome, gender, and as to whether socioeconomic health inequalities are measured in absolute or in relative terms. The aim is to investigate whether absolute and relative socioeconomic health inequalities differ across age groups by indicator of socioeconomic position, health outcome and gender.

Methods

The study sample was derived from the baseline measurement of the LifeLines Cohort Study and consisted of 95,432 participants. Socioeconomic position was measured as educational level and household income. Physical and mental health were measured with the RAND-36. Age concerned eleven 5-years age groups. Absolute inequalities were examined by comparing means. Relative inequalities were examined by comparing Gini-coefficients. Analyses were performed for both health outcomes by both educational level and household income. Analyses were performed for all age groups, and stratified by gender.

Results

Absolute and relative socioeconomic health inequalities differed across age groups by indicator of socioeconomic position, health outcome, and gender. Absolute inequalities were most pronounced for mental health by household income. They were larger in younger than older age groups. Relative inequalities were most pronounced for physical health by educational level. Gini-coefficients were largest in young age groups and smallest in older age groups.

Conclusions

Absolute and relative socioeconomic health inequalities differed cross-sectionally across age groups by indicator of socioeconomic position, health outcome and gender. Researchers should critically consider the implications of choosing a specific age group, in addition to the indicator of socioeconomic position and health outcome, as findings on socioeconomic health inequalities may differ between them.

Joint Effect of Hypertension and Elevated Serum Phosphorus on the Risk of Mortality in National Health and Nutrition Examination Survey-III

Background

Elevated serum phosphorus might aggravate the effect of hypertension on mortality. The objective of this study was to examine the joint effect of hypertension and serum phosphorus on the risk of mortality.

Methods and Results

A large prospective (n=15 833), population-based cohort of participants from the National Health and Nutritional Examination Survey III was examined to test potential synergism between hypertension, elevated serum phosphorus, and the risk of mortality. Interaction on additive scale and multiplicative scale was estimated. After a median follow-up of 14.3 years, 1691 cases of cardiovascular mortality and 3875 cases of all-cause mortality were identified. Interaction was observed between hypertension and elevated serum phosphorus on the additive scale for cardiovascular mortality (relative excess risk due to interaction, 0.99, 95% CI: 0.06; 1.92, adjusted for age, gender, race, and estimated glomerular filtration rate). No statistically significant interaction was found between hypertension and serum phosphorus for all-cause mortality on the additive scale. No significant interaction was detected on the multiplicative scale. In sensitivity analysis, excluding participants who died in first 2 years and adjustment for additional confounders resulted in essentially similar findings.

Conclusions

The joint effect of hypertension and elevated serum phosphorus was larger than the sum of the independent effects on cardiovascular mortality but not on all-cause mortality. Future studies should investigate whether controlling elevated serum phosphorus in hypertensive individuals helps in prevention of extra risk of cardiovascular mortality.