Lutgart Braeckman

Rotating shift work and the metabolic syndrome: a prospective study

BACKGROUNDnSeveral studies have documented on the elevated cardiovascular risk among shift workers. In order to further explore this relation, we aimed at assessing the association between rotating shift work and the incidence of the metabolic syndrome (MetS).nnnMETHODSnIn this population-based prospective study, 1529 employees from several large Belgian companies were followed for a median observation period of 6.6 years with respect to the onset of the MetS and its separate components.nnnRESULTSnAt baseline, 309 men (20.2%) were rotating shift workers. The MetS incidence rate in these shift workers (60.6 per 1000 person-years) was increased in comparison with day workers (37.2 per 1000 person-years) with an odds ratio (95% CI) of 1.77 (1.34-2.32). Multivariate adjustment for potential lifestyle and work-related confounders did only marginally affect the strength of the association. The risk for the development of MetS gradually increased independently with accumulated years of shift work. Rotating shift work not only had an impact on MetS as a cluster of conditions but on each of its individual components as well.nnnCONCLUSIONSnHence, prospective evidence was found that rotating shift work increases the risk for developing the MetS over a period of 6 years.

A century of trends in adult human height

Being taller is associated with enhanced longevity, and higher education and earnings. We reanalysed 1472 population-based studies, with measurement of height on more than 18.6 million participants to estimate mean height for people born between 1896 and 1996 in 200 countries. The largest gain in adult height over the past century has occurred in South Korean women and Iranian men, who became 20.2 cm (95% credible interval 17.5–22.7) and 16.5 cm (13.3–19.7) taller, respectively. In contrast, there was little change in adult height in some sub-Saharan African countries and in South Asia over the century of analysis. The tallest people over these 100 years are men born in the Netherlands in the last quarter of 20th century, whose average heights surpassed 182.5 cm, and the shortest were women born in Guatemala in 1896 (140.3 cm; 135.8–144.8). The height differential between the tallest and shortest populations was 19-20 cm a century ago, and has remained the same for women and increased for men a century later despite substantial changes in the ranking of countries. DOI: http://dx.doi.org/10.7554/eLife.13410.001

Prevalence and Correlates of Poor Sleep Quality and Daytime Sleepiness in Belgian Truck Drivers

Sleepiness and sleep complaints are common among professional drivers. Sleepiness is a considerable problem not only because it affects the drivers well-being, but also because of the consequences for performance and safety. Assessment of the (self-reported) prevalence and research into the risk factors are thus an important health issue and are also indispensable to prevent productivity loss and work-related accidents and injuries. Therefore, the aim of this study was to describe sleeping, driving, and health characteristics of Belgian truck drivers and to determine occupational and individual factors associated with poor sleep quality and daytime sleepiness. Cross-sectional data were collected using a self-administered questionnaire that included the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and Berlin Questionnaire (BQ). The mean (SD) age of the 476 studied truck drivers was 42.7 (10.2) yrs and the mean (SD) body mass index was 27.3 (5.1) kg/m2. Approximately 47% declared that they drove >50 h/wk and found their work schedule unrealistic. The mean (SD) PSQI score was 4.45 (2.7); poor quality of sleep (PSQI >5) was found in 27.2%. The mean (SD) ESS score was 6.79 (4.17); 18% had a score >10. The BQ indicated that 21.5% had a higher risk on obstructive sleep apnea. In multiple logistic regression analysis, low educational level (odds ratio [OR] 1.86), current smoking (OR 1.75), unrealistic work schedule (OR 1.75), and risk for obstructive sleep apnea (OR 2.97) were found to be independent correlates of daytime sleepiness. Poor sleep quality was significantly associated with poor self-perceived health (OR 1.95), unrealistic work schedule (OR 2.85), low job satisfaction (OR 1.91), and less driving experience (OR 1.73). These results show that poor sleep quality and daytime sleepiness were prevalent in Belgian truck drivers. Taking into account that several significant correlates with respect to these sleep problems were identified both at the individual and the occupational level, comprehensive countermeasures to improve working conditions and organization are needed, as well as health promotion interventions, to ensure the safety and well-being of truck drivers. (Author correspondence: lutgart.braeckman@ugent.be)

The association between leisure time physical activity and coronary heart disease among men with different physical work demands: a prospective cohort study

The interplay of occupational and leisure time physical activity (LTPA) in affecting cardiovascular health is subject to debate. This study aimed to examine the independent and interacting associations of leisure time and occupational physical activity (OPA) with the incidence of coronary events within the BELSTRESS cohort. The study included 14,337 middle-aged men free from coronary heart disease at baseline. Standardized questionnaires and clinical examinations were used to assess socio-demographic factors, level of physical activity, job strain and classical coronary risk factors. The incidence of clinical coronary events was monitored during a mean follow-up time of 3.15xa0years. Results demonstrated overall a beneficial relation of LTPA and an adverse relation of physical work demands with cardiovascular health. However, an interaction effect between both physical activity types was observed, showing that men with high physical job demands who also engaged in physical activity during leisure time had an almost four times increased incidence of coronary events after adjusting for socio-demographic and classical coronary risk factors (HR 3.82; 95xa0% CI 1.41–10.36). Stratified analyses revealed that moderate to high physical activity during leisure time was associated with a 60xa0% reduced incidence rate of coronary events in men with low OPA (age adjusted HR 0.40; 95xa0% CI 0.21–0.76), while this protective association was not observed in workers being exposed to high physical work demands (age adjusted HR 1.67; 95xa0% CI 0.63–4.48). These findings suggest that recommendations regarding LTPA should be tailored according to the level of occupational physical activity.

Evaluation of bioaerosol sampling techniques for the detection of Chlamydophila psittaci in contaminated air

Chlamydophila (C.) psittaci, a category B bioterrorism agent, causes respiratory disease in birds and psittacosis or parrot fever in man. The disease spreads aerogenically and no vaccines are available for either birds or man. Highly sensitive C. psittaci bioaerosol monitoring methods are unavailable. We evaluated: (1) dry filtration for collecting C. psittaci from contaminated air using different samplers and membrane filters, (2) impingement into different liquid collection media by use of the AGI-30 impinger and the BioSampler and (3) impaction into newly designed C. psittaci media utilizing the MAS-100 aerosol impactor. For personal bioaerosol sampling, we recommend the use of a gelatin filter in combination with the IOM inhalable dust sampler at an airflow rate of 2L/min. This allowed the detection of 10 organisms of C. psittaci by both PCR and culture. For stationary bioaerosol monitoring, sampling 1000L of air in 10min with the MAS-100 impactor and ChlamyTrap 1 impaction medium was most efficient and made it possible to detect 1 and 10 C. psittaci organisms by PCR and culture, respectively. ChlamyTrap 1 in combination with the MAS-100 impactor might also be applicable for bioaerosol monitoring of viruses.

The relation between psychosocial risk factors and cause-specific long-term sickness absence

BACKGROUNDnThe aim was to study the impact of psychosocial risk factors on long-term sickness absence due to mental health problems (LSA-MH) or musculoskeletal disorders (LSA-MSD) in 2983 Belgian middle-aged workers.nnnMETHODSnData were collected from 1372 male and 1611 female workers in the Belstress III study. Considered psychosocial risk factors were job demands, job control, social support, job strain, efforts, rewards, effort-reward imbalance and bullying. Prospective registered sickness absence data were collected during 12 months follow-up; the causes for long-term sickness absence episodes of at least 15 consecutive days were obtained by contacting the general practitioner of the worker. Multiple logistic regression models were used to investigate the relationship between the psychosocial risk factors and LSA-MH and LSA-MSD.nnnRESULTSnHigher levels of rewards at baseline were independently and significantly associated with a lower risk for LSA-MH. Higher levels of control were associated with a lower risk for LSA-MSD during follow-up. Higher job demands and efforts were significantly related to a lower risk for LSA-MSD. Finally, bullying was significantly and independently related to both LSA-MH and LSA-MSD during the follow-up period.nnnCONCLUSIONSnThese results suggest that psychosocial risk factors are related to LSA-MH and LSA-MSD, of which especially bullying seems to be a potent stressor.

The association between body mass index class, sickness absence, and presenteeism

Objective: To examine the relationship between body mass index class, presenteeism, and prospective registered sickness absence. Methods: Data were collected from 2983 Belgian workers. Presenteeism was assessed by a single question, evaluating the frequency of being at work, despite illness, during the preceding year. Sickness absence data were registered during 12 months follow-up. Multiple logistic regression analysis was conducted. Results: Body mass index class was positively and significantly associated with presenteeism (at least two occasions of working despite illness) in the male employees and was a significant predictor of high sickness absence (at least 10 sick leave days) in the female population. A final multivariate model demonstrated that these relations were only partly mediated by self-rated health. Conclusion: The results of this study suggest a gender difference concerning absenteeism and presenteeism in overweight and obese employees.

Job-Related Stress and Sickness Absence Among Belgian Nurses: A Prospective Study

PURPOSEnThe purpose of this study was to investigate the influence of job stress on sickness absence of nurses and determine the predictive power of the Demand-Control-Support (DCS) model, the Effort-Reward Imbalance-Overcommitment (ERI-OC) model, and a combination of both.nnnDESIGNnA survey was conducted to measure job stress in a sample of 527 Belgian nurses, followed by prospective data collection of sickness absence (long-term, short-term, and multiple episodes).nnnFINDINGSnPerceptions of job strain and ERI increased the odds for long-term (adjusted odds ratio [OR]xa0= 2.26; 99% confidence interval [CI; 1.27-4.04]) and multiple episodes of sickness absence (adjusted ORxa0= 1.64; 95% CI [1.01-2.65]). Iso-strain and ERI-OC increased the odds for long-term (ORxa0= 1.75; 95% CI [0.98-3.11]), multiple episode (adjusted ORxa0= 1.93; 95% CI [1.14-3.26]), and short-term (adjusted ORxa0= 1.69; 95% CI [1.03-2.76]) sickness absence.nnnCONCLUSIONSnThe combined model of DCS and ERI-OC predicts the odds for long-term and short-term sickness absence and multiple episodes.nnnCLINICAL RELEVANCEnThis study has implications for human resources management in nursing organizations. Nursing administrators are advised to monitor and balance nurses job demands and efforts. They should recognize the importance of social support, job control, job rewards, and overcommitment in order to reduce the job stress of nurses.

Assessment of Chlamydia suis Infection in Pig Farmers

Chlamydia suis infections are endemic in domestic pigs in Europe and can lead to conjunctivitis, pneumonia, enteritis and reproductive failure. Currently, the knowledge on the zoonotic potential of C.xa0suis is limited. Moreover, the last decades, porcine tetracycline resistant C.xa0suis strains have been isolated, which interfere with treatment of chlamydial infections. In this study, the presence of C.xa0suis was examined on nine Belgian pig farms, using Chlamydia culture and a C.xa0suis specific real-time PCR in both pigs and farmers. In addition to diagnosis for C.xa0suis, the farmers samples were examined using a Chlamydia trachomatis PCR. Additionally, the Chlamydia isolates were tested for the presence of the tet(C) resistance gene. C. DNA was demonstrated in pigs on all farms, and eight of nine farmers were positive in at least one anatomical site. None of the farmers tested positive for C. trachomatis. Chlamydia suis isolates were obtained from pigs of eight farms. Nine porcine C.xa0suis isolates possessing a tet(C) gene were retrieved, originating from three farms. Moreover, C.xa0suis isolates were identified in three human samples, including one pharyngeal and two rectal samples. These findings suggest further research on the zoonotic transfer of C.xa0suis from pigs to humans is needed.

Association between psychosocial characteristics of work and presenteeism: a cross-sectional study

OBJECTIVESnThis study aimed at investigating cross-sectional relationships between psychosocial characteristics of work and presenteeism in a sample of Belgian middle-aged workers.nnnMATERIAL AND METHODSnData were collected from 1372 male and 1611 female workers in the Belstress III study. Psychosocial characteristics assessed by the use of self-administered questionnaires were: job demands, job control, social support, efforts, rewards, bullying, home-to-work conflict and work-to-home conflict. Presenteeism was measured using a single item question, and it was defined as going to work despite illness at least 2 times in the preceding year. Logistic regression models were used to investigate the relationship between psychosocial characteristics and presenteeism, while adjusting for several socio-demographic, health-related variables and neuroticism. An additional analysis in a subgroup of workers with good self-rated health and low neuroticism was conducted.nnnRESULTSnThe prevalence of presenteeism was 50.6%. Overall results, adjusted for major confounders, revealed that high job demands, high efforts, low support and low rewards were associated with presenteeism. Furthermore, a significant association could be observed for both bullying and work-to-home conflict in relation to presenteeism. The subgroup analysis on a selection of workers with good self-rated health and low neuroticism generally confirmed these results.nnnCONCLUSIONSnBoth job content related factors as well as work contextual psychosocial factors were significantly related to presenteeism. These results suggest that presenteeism is not purely driven by the health status of a worker, but that psychosocial work characteristics also play a role.