Development and validation of a risk prediction model for work disability: multicohort study

The effect of improving psychosocial stressors on psychological distress: a quasi-experiment of Finnish health and social care workers

AIMS

To examine how a positive change in one to three psychosocial stressors (job demands, job rewards, and workplace social capital) influenced psychological distress.

METHODS

The analysis included 3605 Finnish health and social services workers who completed surveys in 2019, 2020 and 2021. A logistic regression model was used to estimate the propensity score of experiencing a positive change in one to three psychosocial stressors between 2019 and 2020. We balanced the baseline characteristics with propensity scoring. A generalised linear model with a binomial distribution and a log link function was used to compare the quasi-intervention and quasi-control groups for the risk of psychological distress in 2021.

RESULTS

Among the total sample, neither improving a single stressor nor two or three stressors affected psychological distress. However, among employees younger than 50 years, improving two or three psychosocial stressors in 2019-2020 decreased the risk of moderate to severe psychological distress in 2021 by 41% (risk ratio 0.59, 95% confidence interval 0.36-0.96). Among employees aged 50 years or older, improving job rewards lowered the risk of mild to severe psychological distress by 23% (risk ratio 0.77, 95% confidence interval 0.62-0.96).

CONCLUSIONS

The results of this quasi-experiment suggest that the positive effect of improving psychosocial stressors is stronger among younger than older workers. Future interventions should be customised for different ages and aim to improve accumulated work stressors and individual stress-coping skills.

Predicting long-term sickness absence with employee questionnaires and administrative records: a prospective cohort study of hospital employees

OBJECTIVE

This study aimed to compare the utility of risk estimation derived from questionnaires and administrative records in predicting long-term sickness absence among shift workers.

METHODS

This prospective cohort study comprised 3197 shift-working hospital employees (mean age 44.5 years, 88.0% women) who responded to a brief 8-item questionnaire on work disability risk factors and were linked to 28 variables on their working hour and workplace characteristics obtained from administrative registries at study baseline. The primary outcome was the first sickness absence lasting ≥90 days during a 4-year follow-up.

RESULTS

The C-index of 0.73 [95% confidence interval (CI) 0.70-0.77] for a questionnaire-only based prediction model, 0.71 (95% CI 0.67-0.75) for an administrative records-only model, and 0.79 (95% CI 0.76-0.82) for a model combining variables from both data sources indicated good discriminatory ability. For a 5%-estimated risk as a threshold for positive test results, the detection rates were 76%, 74%, and 75% and the false positive rates were 40%, 45% and 34% for the three models. For a 20%-risk threshold, the corresponding detection rates were 14%, 8%, and 27% and the false positive rates were 2%, 2%, and 4%. To detect one true positive case with these models, the number of false positive cases accompanied varied between 7 and 10 using the 5%-estimated risk, and between 2 and 3 using the 20%-estimated risk cut-off. The pattern of results was similar using 30-day sickness absence as the outcome.

CONCLUSIONS

The best predictive performance was reached with a model including both questionnaire responses and administrative records. Prediction was almost as accurate with models using only variables from one of these data sources. Further research is needed to examine the generalizability of these findings.

Predicting work disability among people with chronic conditions: a prospective cohort study

Few risk prediction scores are available to identify people at increased risk of work disability, particularly for those with an existing morbidity. We examined the predictive performance of disability risk scores for employees with chronic disease. We used prospective data from 88,521 employed participants (mean age 43.1) in the Finnish Public Sector Study including people with chronic disorders: musculoskeletal disorder, depression, migraine, respiratory disease, hypertension, cancer, coronary heart disease, diabetes, comorbid depression and cardiometabolic disease. A total of 105 predictors were assessed at baseline. During a mean follow-up of 8.6 years, 6836 (7.7%) participants were granted a disability pension. C-statistics for the 8-item Finnish Institute of Occupational Health (FIOH) risk score, comprising age, self-rated health, number of sickness absences, socioeconomic position, number of chronic illnesses, sleep problems, BMI, and smoking at baseline, exceeded 0.72 for all disease groups and was 0.80 (95% CI 0.80-0.81) for participants with musculoskeletal disorders, 0.83 (0.82-0.84) for those with migraine, and 0.82 (0.81-0.83) for individuals with respiratory disease. Predictive performance was not significantly improved in models with re-estimated coefficients or a new set of predictors. These findings suggest that the 8-item FIOH work disability risk score may serve as a scalable screening tool in identifying individuals with increased risk for work disability.

Association of poor perceived work ability and psychosocial work-related factors in health and social service worker age groups: a cross-sectional study

OBJECTIVE

Previous work ability studies have primarily focused on old workers and physical health. This study investigated how poor perceived work ability (PPWA) is associated with work-related factors in different health and social service (HSS) worker age groups.

DESIGN

Cross-sectional survey in 2020.

SETTING

HSS employees (general HSS and eldercare) in nine Finnish public sector organisations.

PARTICIPANTS

All employees who were employed in the organisation completed self-reported questionnaires. Of the original sample (N=24 459, response rate 67%), 22 528 gave consent for research use.

PRIMARY AND SECONDARY OUTCOME MEASURES

Participants evaluated their psychosocial work environment and work ability. Lowest decile of work ability was categorised as poor. The association between psychosocial work-related factors and PPWA in different age-groups of HSS workers, adjusting for perceived health, was analysed with logistic regression.

RESULTS

The proportion of PPWA was highest in shift workers, eldercare employees, practical nurses and registered nurses. Considerable variation between age groups exists in the work-related psychosocial factors associated with PPWA. Among young employees engaging leadership and working time and work task autonomy were statistically significant, whereas in middle-aged and old employees procedural justice and ethical strain were highlighted. The strength of the association with perceived health also differs in age groups (young: OR=3.77, 95% CI 3.30 to 4.30; middle-aged: OR=4.66, 95% CI 4.22 to 5.14; old: OR=6.16, 95% CI 5.20 to 7.18).

CONCLUSIONS

Young employees would benefit from engaging leadership and mentoring, and from more working time and work task autonomy. As employees get older they would benefit more from job modification and from ethical and just organisation culture.

A randomized controlled trial protocol for persistent physical symptoms associated with indoor environment or chronic fatigue: Effectiveness of video-based functional case conceptualization and web-program for improving quality of life

Introduction

Persistent physical symptoms (PPS) refer to symptoms that cannot be fully explained by structural bodily pathology or by environmental factors. Their impact on daily functioning varies from mild to severe disability. So far, evidence-based treatments for PPS have resulted in only small to moderate effects. Treatment protocols with a stronger orientation toward personalized approaches are needed to improve the efficacy and applicability of treatment. In this study, we aim to assess the effect of an online individual case conceptualization with web-based program for PPS. This study is conducted among two focus groups: patients with indoor air-related symptoms and patients with chronic fatigue syndrome.

Methods and analyses

Using a randomized controlled design (RCT) with two parallel groups in a 1:1 ratio, we will compare individual video-based case conceptualization with a web-based program based on Acceptance and Commitment Therapy (ACT), combined with treatment as usual, with treatment as usual only. The web-based program consists of ten modules, each lasting 1 week and including training. The planned sample size is 124 eligible patients without attrition. The primary outcome will be the health-related quality of life as measured by the 15D questionnaire. The secondary outcome measures will include questionnaires on psychiatric and physical symptoms, illness perceptions, psychological flexibility, and work ability. We will also use national registers to obtain information on the use of healthcare and social benefits to complete patient-reported outcomes. Data collection began in August 2020 and will continue until 2023.

Discussion

This trial will provide information on the effects and usefulness of an online administrated individual case conceptualization and an ACT-based web-program on PPS.

Ethics and dissemination

The Ethics Committee of the Hospital District of Helsinki and Uusimaa, Finland, has granted approval for the study. The results will be published in peer-reviewed journals.

Clinical Trial Registration

Clinicaltrials.gov, identifier NCT04532827 preresults.

Prediction of bullying at work: A data-driven analysis of the Finnish public sector cohort study

AIM

To determine the extent to which change in (i.e., start and end of) workplace bullying can be predicted by employee responses to standard workplace surveys.

METHODS

Responses to an 87-item survey from 48,537 Finnish public sector employees at T1 (2017-2018) and T2 (2019-2020) were analyzed with least-absolute-shrinkage-and-selection-operator (LASSO) regression. The predictors were modelled both at the individual- and the work unit level. Outcomes included both the start and the end of bullying. Predictive performance was evaluated with C-indices and density plots.

RESULTS

The model with best predictive ability predicted the start of bullying with individual-level predictors, had a C-index of 0.68 and included 25 variables, of which 6 remained in a more parsimonious model: discrimination at work unit, unreasonably high workload, threat that some work tasks will be terminated, working in a work unit where everyone did not feel they are understood and accepted, having a supervisor who was not highly trusted, and a shorter time in current position. Other models performed even worse, either from the point of view of predictive performance, or practical useability.

DISCUSSION

While many bivariate associations between socioeconomic characteristics, work characteristics, leadership, team climate, and job satisfaction were observed, reliable individualized detection of individuals at risk of becoming bullied at workplace was not successful. The predictive performance of the developed risk scores was suboptimal, and we do not recommend their use as an individual-level risk prediction tool. However, they might be useful tool to inform decision-making when planning the contents of interventions to prevent bullying at an organizational level.

Return to work following anterior cruciate ligament reconstruction

BACKGROUND AND PURPOSE

Amongst people of working age, the return to work (RTW) after anterior cruciate ligament (ACL) reconstruction is an important marker of success of surgery. We determined when patients are able to return to work after ACL reconstruction and identified factors that are associated with the timing of RTW.

PATIENTS AND METHODS

We used logistic regression analyses to examine patient-related factors that may be associated with the length of RTW (above vs. below the median 59 days) after arthroscopic ACLR in a large cohort of patients working in the public sector in Finland (n = 803; n = 334 male, n = 469 female; mean age 41 years [SD 8.6]).

RESULTS

The mean length of RTW was 65 days (SD 41). Higher odds ratios (OR) were observed for age groups 40-49 and ≥ 50 years compared with ≤ 30 years old (OR 2.0, 95% confidence interval 1.3-3.1 and 2.0, 1.2-3.4, respectively); for lower level non-manual and manual work compared with higher level non-manual work (3.0, 2.0-4.3 and 4.9, 3.4-7.0, respectively); and for those who had been on sick leave > 30 days in the preceding year (2.0, 1.4-2.9). Sex, comorbid conditions, preceding antidepressant treatment and concomitant procedures were not associated with the length of RTW.

INTERPRETATION

Factors associated with prolonged sick leave beyond the median time of 59 days are higher age, lower occupational status, and preoperative sick leaves.

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.

Association between work ability and work stressors: cross-sectional survey of elderly services and health and social care service employees

BACKGROUND

Work in the health and social care services (HSS) is very stressful and sickness absences are high. Nevertheless, little is known about their work stressors and work ability. The first aim of this study is to describe the prevalence of different work stressors and their accumulation among eldercare workers compared to general HSS workers. Second aim is to analyze associations between different work stressors and work ability and thus provide information on factors that are important in enhancing work ability.

METHODS

This cross-sectional survey examined HSS employees in Finland in 2020. The response rate was 67% (N = 22,502). Descriptive analyses were used to describe the control variables and the differences between the work stressors of general HSS and eldercare employees. After this, multinomial logistic regression analysis revealed the association between work stressors and work ability.

RESULTS

Eldercare employees experienced more often moral distress than HSS employees in general, and this further lowers their work ability. Single work stressors--Karasek's strain, Siegrist's ERI, organizational injustice and moral distress--increased the odds of low work ability (OR range 1.4-2.5) in comparison to no work stressors. However, the association with single stressors was roughly one third of that with the accumulation of all four work stressors (OR = 6.8). Thus, the accumulation of several stressors was most harmful for work ability.

CONCLUSIONS

This study provides novel information on the accumulation of work stressors in relation to work ability. The results suggest that in order to enhance work ability, HSS organizations should pay more attention to preventing several stressors from accumulating. Eldercare organizations in particular need to develop effective measures for lowering moral distress.

Return to work after lumbar disc herniation surgery: an occupational cohort study

Background and purpose - Lumbar disc herniation is a common surgically treated condition in the working-age population. We assessed health-related risk factors for return to work (RTW) after excision of lumbar disc herniation. Previous studies on the subject have had partly contradictory findings.Patients and methods - RTW of 389 (n = 111 male, n = 278 female; mean age 46 years, SD 8.9) employees who underwent excision of lumbar disc herniation was assessed based on the Finnish Public Sector Study (FPS). Baseline information on occupation, preceding health, and health-risk behaviors was derived from linkage to national health registers and FPS surveys before the operation. The likelihood of RTW was analyzed using Cox proportional hazard univariable and multivariable modelling.Results - 95% of the patients had returned to work at 12 months after surgery, after on average 78 days of sickness absence. Faster RTW in the univariable Cox model was associated with a small number of sick leave days (< 30 days) before operation (HR 1.3, 95% CI 1.1-1.6); high occupational position (HR 1.6, CI 1.2-2.1); and age under 40 years (HR 1.5, CI 1.1-1.9). RTW was not associated with sex or the health-related risk factors obesity, physical inactivity, smoking, heavy alcohol consumption, poor self-rated health, psychological distress, comorbid conditions, or purchases of pain or antidepressant medications in either the univariable or multivariable model.Interpretation - Almost all employees returned to work after excision of lumbar disc herniation. Older age, manual job, and prolonged sick leave before the excision of lumbar disc herniation were risk factors for delayed return to work after the surgery.

Labor Market Participation Before and After Long-Term Part-Time Sickness Absence in Finland: A Population-Based Cohort Study

OBJECTIVE

To examine trends in labor market participation among those with long-term part-time or long-term full-time sickness absence.

METHODS

Finnish population-based cohort study including 3406 individuals with greater than 30-day part-time sickness absence in 2011 and 42,944 individuals with greater than 30-day full-time sickness absence in 2011.

RESULTS

Compared to previous years, the rates of sickness absence and vocational rehabilitation increased after 2011 in both groups. Sickness absence rate was higher in 2012 in the full-time sickness absence group than in the part-time sickness absence group. An increasing trend in unemployment after 2011 was observed in both groups, but the absolute level of unemployment was higher in the full-time sickness absence group.

CONCLUSION

Long-term part-time sickness absence seems to mark a decline in labor market participation, but the decline is smaller than that in employees with full-time sickness absence.

Quality improvement activity in occupational healthcare associated with reduced need for disability retirement: A Bayesian mixed effects modelling study in Finland

Objectives There is evidence that occupational healthcare (OHC) may improve employees' work ability. This research was designed to study whether common quality improvement (QI) activities in the OHC quality network (OQN) - a voluntary collaborative forum - can reduce the need for disability pensions. Methods The study population comprised employees under the care of 19 OHC units in Finland affiliated with the OQN. The association of 12 QI activities with new disability pensions during the years 2011-2017 was analyzed by Bayesian mixed effects modelling. Results Patients of OHC units affiliated with the OQN have fewer full permanent disability pensions [odds ratio (OR) 0.77, 95% credible interval (CI) 0.60-0.98] and full provisional disability pensions (OR 0.68, 95% CI 0.53-0.87) than patients of unaffiliated units. Of the studied QI activities, the measurements of intervening in excessive use of alcohol had the strongest association with the incidence of all disability pensions (OR 0.53, 95% CI 0.41-0.68). Participation in the focus of work measurements and quality facilitator training was also associated with the reduced incidence of disability pensions (OR 0.84, 95% CI 0.71-0.98, and OR 0.92, 95 CI 0.84-0.99, respectively). Conclusions Affiliation with a quality network seemed to improve outcomes by reducing full disability pensions or replacing them by partial disability pensions. Some QI activities in the OQN were associated with a reduction of disability pensions.

Pre-Existing and New-Onset Depression and Anxiety Among Workers With Injury or Illness Work Leaves

To examine the influence of depression and/or anxiety on work leaves and the impact of work leaves on experiencing a new-onset depression and/or anxiety disorder.

The influence of antidepressant and psychotherapy treatment adherence on future work leaves for patients with major depressive disorder

BACKGROUND

Depression is the greatest contributor to worldwide disability. The purpose of this study was to understand the influence of antidepressant and psychotherapy treatment adherence on future work leaves for patients with major depressive disorder.

METHODS

Patients with a newly diagnosed major depressive disorder (n = 26,256) were identified in IBM® Watson™ MarketScan® medical and disability claims databases. Antidepressant and psychotherapy adherence metrics were evaluated in the acute phase of treatment, defined as the 114 days following the depression diagnosis. Multiple variable Cox proportional hazards regression models evaluated the influence of antidepressant and/or psychotherapy adherence on future injury or illness work leaves.

RESULTS

The majority of work leaves in the 2-year follow-up period occurred in the acute phase of treatment (71.2%). Among patients without a work leave in the acute phase and who received antidepressants and/or psychotherapy (n = 19,994), those who were adherent to antidepressant or psychotherapy treatment in the acute phase had a 16% (HR = 0.84, 95% CI = 0.77-0.91) reduced risk of a future work leave compared to treatment non-adherent patients. Patients who were non-adherent or adherent to antidepressant treatment had a 22% (HR = 1.22, 95% CI = 1.11-1.35) and 13% (HR = 1.13, 95% CI = 1.01-1.27) greater risk of a future work leave, respectively, than patients not receiving antidepressant treatment. Conversely, patients who were non-adherent or adherent to psychotherapy treatment had a 9% (HR = 0.91, 95% CI = 0.81-1.02) and 28% (HR = 0.72, 95% CI = 0.64-0.82) reduced risk of a future work leave, respectively, than patients not receiving psychotherapy treatment.

CONCLUSIONS

This analysis suggests that treatment adherence may reduce the likelihood of a future work leave for patients with newly diagnosed major depressive disorder. Psychotherapy appears more effective than antidepressants in reducing the risk of a future work leave.

Networking of occupational health care units promotes reduction of permanent disability pensions among workers they care: A register-based study controlled by benchmarking with a 5-year follow-up

OBJECTIVES

Early retirement due to disability is a problem in Finland. That causes pension costs that are heavy for the society. This study was designed to find out whether a quality network can support the reduction in incident disability pensions and promote a shift from full to partial disability pensions.

METHODS

The study population (N = 41 472 in 2016) consisted of municipal employees whose occupational health care (OHC) was provided by the members of the Finnish Occupational Health Quality Network (OQN). The comparison population consisted of all municipality employees whose OHC was provided by non-members of the OQN (N = 340 479 in 2016). The outcomes were measured by comparing the trends in incident disability pensions of full and partial permanent pension and full and partial provisional pension, partial/full pension indexes from 2011 to 2016 according to the principles of Benchmarking Controlled Trials. Linear regression models were used to explore the dynamics of different pension forms. Regression coefficients were calculated to show the average change per year.

RESULTS

The incidence of permanent disability pensions decreased faster in the study population (P for trend .03) and the study group showed a stronger shift from full to partial permanent pensions (P for trend <.001).

CONCLUSION

Quality networking between OHC units including common goal setting, systematic quality improvement, and repeated quality measurements decreased new permanent disability pensions and increased partial permanent pensions. Such changes are important while thriving for increased work participation.

Predicting the duration of sickness absence spells due to back pain: a population-based study from Sweden

Objectives

We aimed to develop and validate a prediction model for the duration of sickness absence (SA) spells due to back pain (International Statistical Classification of Diseases and Related Health Problems 10th Revision: M54), using Swedish nationwide register microdata.

Methods

Information on all new SA spells >14 days from 1 January 2010 to 30 June 2012 and on possible predictors were obtained. The duration of SA was predicted by using piecewise constant hazard models. Nine predictors were selected for the final model based on a priori decision and log-likelihood loss. The final model was estimated in a random sample of 70% of the SA spells and later validated in the remaining 30%.

Results

Overall, 64 048 SA spells due to back pain were identified during the 2.5 years; 74% lasted ≤90 days, and 9% >365 days. The predictors included in the final model were age, sex, geographical region, employment status, multimorbidity, SA extent at the start of the spell, initiation of SA spell in primary healthcare and number of SA days and specialised outpatient healthcare visits from the preceding year. The overall c-statistic (0.547, 95% CI 0.542 to 0.552) suggested a low discriminatory capacity at the individual level. The c-statistic was 0.643 (95% CI 0.634 to 0.652) to predict >90 days spells, 0.686 (95% CI 0.676 to 0.697) to predict >180 spells and 0.753 (95% CI 0.740 to 0.766) to predict >365 days spells.

Conclusions

The model discriminates SA spells >365 days from shorter SA spells with good discriminatory accuracy.

Are patient-related pre-operative factors influencing return to work after total knee arthroplasty

BACKGROUND

Osteoarthritis is one of the leading causes of disability in working-age patients. The total number of working-age patients undergoing total-knee arthroplasty (TKA) is continuously increasing. The purpose of this study was to identify predictive factors related to general health, health risk behaviors and socioeconomic status influencing the rate of return to work after a TKA.

METHODS

Overall there were 151,901 patients included in the Finnish Public Sector (FPS) study. The response rate varied between 65 and 73% during the study period. We used Cox proportional hazard models to examine patient-related predictive factors that may influence the rate of return to work after TKA in a cohort of patients (n = 452; n = 362 female; mean age 56.4 years). Predictive factors were measured on average 3.6 years before the operation.

RESULTS

Of the patients, 87% returned to work within one year after TKA at a mean of 116 calendar days. In multivariate analysis, patients at sick-leave ≤30 days during the last year before surgery were 2.2 times (95% confidence interval 1.72-2.92) more likely to return to work compared with those with >30 days of sick-leave. Compared with patients in manual work, those in higher or lower level non-manual work showed a 2.6-fold (1.95-3.52) and 1.5-fold (1.15-1.92) increased probability of returning to work. Age, sex, health risk behaviors, obesity, physical comorbidities, common mental disorders, and other studied health-related factors were not associated with the rate of return to work.

CONCLUSIONS

Non-manual job, good self-rated general health and preoperative sick leave ≤30 days are associated with a higher rate of return to work.

Prediction of pre-eclampsia: review of reviews

OBJECTIVE

Primary studies and systematic reviews provide estimates of varying accuracy for different factors in the prediction of pre-eclampsia. The aim of this study was to review published systematic reviews to collate evidence on the ability of available tests to predict pre-eclampsia, to identify high-value avenues for future research and to minimize future research waste in this field.

METHODS

MEDLINE, EMBASE and The Cochrane Library including DARE (Database of Abstracts of Reviews of Effects) databases, from database inception to March 2017, and bibliographies of relevant articles were searched, without language restrictions, for systematic reviews and meta-analyses on the prediction of pre-eclampsia. The quality of the included reviews was assessed using the AMSTAR tool and a modified version of the QUIPS tool. We evaluated the comprehensiveness of search, sample size, tests and outcomes evaluated, data synthesis methods, predictive ability estimates, risk of bias related to the population studied, measurement of predictors and outcomes, study attrition and adjustment for confounding.

RESULTS

From 2444 citations identified, 126 reviews were included, reporting on over 90 predictors and 52 prediction models for pre-eclampsia. Around a third (n = 37 (29.4%)) of all reviews investigated solely biochemical markers for predicting pre-eclampsia, 31 (24.6%) investigated genetic associations with pre-eclampsia, 46 (36.5%) reported on clinical characteristics, four (3.2%) evaluated only ultrasound markers and six (4.8%) studied a combination of tests; two (1.6%) additional reviews evaluated primary studies investigating any screening test for pre-eclampsia. Reviews included between two and 265 primary studies, including up to 25 356 688 women in the largest review. Only approximately half (n = 67 (53.2%)) of the reviews assessed the quality of the included studies. There was a high risk of bias in many of the included reviews, particularly in relation to population representativeness and study attrition. Over 80% (n = 106 (84.1%)) summarized the findings using meta-analysis. Thirty-two (25.4%) studies lacked a formal statement on funding. The predictors with the best test performance were body mass index (BMI) > 35 kg/m² , with a specificity of 92% (95% CI, 89-95%) and a sensitivity of 21% (95% CI, 12-31%); BMI > 25 kg/m² , with a specificity of 73% (95% CI, 64-83%) and a sensitivity of 47% (95% CI, 33-61%); first-trimester uterine artery pulsatility index or resistance index > 90^th centile (specificity 93% (95% CI, 90-96%) and sensitivity 26% (95% CI, 23-31%)); placental growth factor (specificity 89% (95% CI, 89-89%) and sensitivity 65% (95% CI, 63-67%)); and placental protein 13 (specificity 88% (95% CI, 87-89%) and sensitivity 37% (95% CI, 33-41%)). No single marker had a test performance suitable for routine clinical use. Models combining markers showed promise, but none had undergone external validation.

CONCLUSIONS

This review of reviews calls into question the need for further aggregate meta-analysis in this area given the large number of published reviews subject to the common limitations of primary predictive studies. Prospective, well-designed studies of predictive markers, preferably randomized intervention studies, and combined through individual-patient data meta-analysis are needed to develop and validate new prediction models to facilitate the prediction of pre-eclampsia and minimize further research waste in this field. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Work Loss Before and After Diagnosis of Crohn's Disease

BACKGROUND

The aim of this study was to examine work loss in patients with Crohn's disease.

METHODS

Using nationwide registers, we identified incident patients with Crohn's disease (2007-2010) and population comparator subjects without inflammatory bowel disease, matched by age, sex, calendar year, health care region, and education level. We assessed the number of lost workdays due to sick leave and disability pension from 5 years before to 5 years after first diagnosis of Crohn's disease or end of follow-up (September 30, 2015).

RESULTS

Among the 2015 incident Crohn's disease patients (median age, 35 years; 50% women), both the proportion with work loss and the mean annual number of lost workdays were larger 5 years before diagnosis (25%; mean, 45 days) than in the 10,067 comparators (17%; mean, 29 days). Increased work loss was seen during the year of diagnosis, after which it declined to levels similar to before diagnosis. Of all patients, 75% had no work loss 24-12 months before diagnosis. Of them, 84% had full work ability also 12-24 months after diagnosis. In patients with total work loss (8.3% of all) before diagnosis, 83% did not work after. Among those with full work ability before diagnosis, the absolute risk of having total work loss after diagnosis was 1.4% (0.43% in the comparators). Our results were consistent across several sensitivity analyses using alternative definitions for date of diagnosis.

CONCLUSIONS

Patients with Crohn's disease had increased work loss several years before diagnosis, possibly explained by comorbidity or by diagnostic delay.

Return to work after primary total hip arthroplasty: a nationwide cohort study

Background and purpose - While the number of working-age patients undergoing total hip arthroplasty (THA) is increasing, the effect of the surgery on patients' return to work (RTW) is not thoroughly studied. We aimed to identify risk factors of RTW after THA among factors related to demographic variables, general health, health risk behaviors, and socioeconomic status. Patients and methods - We studied 408 employees from the Finnish Public Sector (FPS) cohort (mean age 54 years, 73% women) who underwent THA. Information on demographic and socioeconomic variables, preceding health, and health-risk behaviors was derived from linkage to national health registers and FPS surveys before the operation. The likelihood of return to work was examined using Cox proportional hazard modeling. Results - 94% of the patients returned to work after THA on average after 3 months (10 days to 1 year) of sickness absence. The observed risk factors of successful return to work were: having < 30 sick leave days during the last year (HR 1.8; 95% CI 1.4-2.3); higher occupational position (HR 2.2; CI 1.6-2.9); and BMI < 30 (HR 1.4; CI 1.1-1.7). Age, sex, preceding health status, and health-risk behaviors were not correlated with RTW after the surgery. Interpretation - Most employees return to work after total hip arthroplasty. Obese manual workers with prolonged sick leave before the total hip replacement were at increased risk of not returning to work after the surgery.

The effect of smoking cessation on work disability risk: a longitudinal study analysing observational data as non-randomized nested pseudo-trials

BACKGROUND

Smoking increases disability risk, but the extent to which smoking cessation reduces the risk of work disability is unclear. We used non-randomized nested pseudo-trials to estimate the benefits of smoking cessation for preventing work disability.

METHODS

We analysed longitudinal data on smoking status and work disability [long-term sickness absence (≥90 days) or disability pension] from two independent prospective cohort studies-the Finnish Public Sector study (FPS) (n = 7393) and the Health and Social Support study (HeSSup) (n = 2701)-as 'nested pseudo-trials'. All the 10 094 participants were smokers at Time 1 and free of long-term work disability at Time 2. We compared the work disability risk after Time 2 of the participants who smoked at Time 1 and Time 2 with that of those who quit smoking between these times.

RESULTS

Of the participants in pseudo-trials, 2964 quit smoking between Times 1 and 2. During the mean follow-up of 4.8 to 8.6 years after Time 2, there were 2197 incident cases of work disability across the trials. Quitting smoking was associated with a reduced risk of any work disability [summary hazard ratio = 0.89, 95% confidence interval (CI) 0.81-0.98]. The hazard ratio for the association between quitting smoking and permanent disability pension (928 cases) was of similar magnitude, but less precisely estimated (0.91, 95% CI 0.81-1.02). Among the participants with high scores on the work disability risk score (top third), smoking cessation reduced the risk of disability pension by three percentage points. Among those with a low risk score (bottom third), smoking cessation reduced the risk by half a percentage point.

CONCLUSIONS

Our results suggest an approximately 10% hazard reduction of work disability as a result of quitting smoking.

Sick Leave and Disability Pension in Prevalent Patients With Crohn's Disease

BACKGROUND AND AIMS

Crohn's disease may affect the ability to work and lead to permanent disability. We aimed to investigate work loss in prevalent patients.

METHODS

We identified patients with Crohn's disease and general population comparators matched by sex, birth year, healthcare region and education. We assessed days of sick leave and disability pension retrieved from the Swedish Social Insurance Agency and estimated the absolute and relative risk of receiving disability pension [minimum 25% work impairment].

RESULTS

In 2014, the 20638 Crohn's disease patients [median age 44 years] had more than twice as many mean lost workdays [disability pension: 44; sick leave: 19] as the 102038 comparators [disability pension: 20; sick leave: 8], mean difference 35 days [95% confidence interval 33-37]. However, the majority had no lost workdays [68% of patients and 85% of comparators]. The proportion of patients receiving disability pension was 15% (6.5% in the comparators, risk ratio 2.34 [2.25-2.43]) and was higher in all subgroups, especially in female patients [28% vs 13% in the comparators], in those with ≤9 years of education [41% vs 23%] and in ages 60-64 years [46% vs 25%]. The relative risk of disability pension within the patient cohort [adjusted for age, sex, region and education] was higher in patients with complicated disease behaviour, extraintestinal manifestations, need of surgery or treatment with biologics. The differences between patients and comparators remained when comparing other calendar years [2006-2013].

CONCLUSION

Work loss was found in approximately one-third of patients. The mean number of lost workdays was twice as high as in the comparators.