Infant mortality in the Flemish Region of Belgium 1999-2008: a time-to-event analysis.

BACKGROUND: When calculating life expectancy, it is usually assumed that deaths are uniformly distributed within each of the age intervals. As most of the infant deaths are neonatal deaths, this calls for a better assessment for that age group. METHODS: The Flemish unified death and birth certificates database for all calendar years between 1999 and 2008 was used. A Kaplan-Meier survival analysis on a yearly basis was performed to assess the mean time-to-event and to compare survival curves between both genders. RESULTS: Over the last years, a slight though not steady decrease of the infant mortality rate is observed. In 2008, the probability among live births of dying before their first anniversary is 4.6‰ in boys and 3.5‰ in girls. The large majority (about 85%) of these have died in their year of birth. The mean survival time of deaths in their year of birth was found to centre around 1 month (about 30 days), which results in a 'mean proportion of the calendar year lived' (k1) close to 0.09. Among those who died in the year after their year of birth yet before their first anniversary, no such concentration in time of the deaths is observed. Differences between the gender groups are small and generally not statistically significant. CONCLUSION: Statistics Belgium, the federal statistics office, imputes a value for k1 equal to 0.1 for infant deaths in their year of birth when calculating life expectancy. Our data fully support this value. We think such refinement is generally feasible in calculating life expectancy.

Job stress and major coronary events: results from the Job Stress, Absenteeism and Coronary Heart Disease in Europe study.

AIMS: The intention of this study is to investigate the relationship of the demands/control/strain model with hard coronary events in an epidemiological, prospective, multicenter, European study. METHODS AND RESULTS: Six cohorts (Brussels, Ghent, Lille, Barcelona, Göteborg and Malmö) from four European countries (Belgium, France, Spain and Sweden) consisting of 21 111 middle-aged male subjects participated between 1993 and 1996 in the baseline survey of the Job Stress, Absenteeism and Coronary Heart Disease in Europe (JACE) study. The Karasek strain model of psychological demands (five items)/control (nine items) was used. During a mean follow-up of 40 months 185 acute coronary events or coronary deaths were observed. Age-adjusted hazard ratios (HRs) for developing an acute coronary event were 1.46 [CI 95% confidence interval (1.08-1.97)] for high against low psychological demands and 1.53 (95% CI 1.0-2.35) for strained (high demands plus low control) against relaxed (low demands plus high control) groups. After adjustment for standard cardiovascular risk factors the HR for developing a coronary event for those above or equal to the median against those below the median of psychological demands was 1.46 (95% CI 1.08-1.97) whereas the HR for strained against relaxed groups is 1.46 (95% CI 0.96-2.25). Sensitivity analyses confirmed the robustness of the results. CONCLUSION: In this European, multicenter, prospective, epidemiological study the Karasek job strain model was an independent predictor of acute coronary events, with the psychological demands scale emerging as the important component.

Increased absenteeism from work among aware and treated hypertensive and hypercholesterolaemic patients.

AIM: The 'labelling hypothesis' was introduced on the basis of the observation that labelling subjects with blood pressure elevation as hypertensive was associated with an increase in sickness absence. In the Belstress I study this hypothesis was analysed in the same way for the possible influence on sick leave of labelling persons with elevated cholesterol as hypercholesterolaemic. METHODS AND RESULTS: The Belstress I cohort concerns a sample of more than 16,000 men and 5,000 women at work in 24 Belgian industries in various sectors. Baseline data were collected by questionnaire and clinical examination. Awareness was defined as answering positively to the question 'did a physician ever tell you that your blood pressure/serum cholesterol was too high?' Sick leave data were independently and objectively recorded during 1 year following the screening. Sick leave was treated in a dichotomous way whereby the event was defined as being in the highest quartile of the annual number of days of sick leave (10 days or more for men and 15 days or more for women) or as being in the highest quartile of the annual number of spells of sick leave (two spells or more for both sexes). Gender-specific logistic regression analyses were performed, with adjustment for a large set of covariates. A positive association was observed between both awareness of hypertension and awareness of hypercholesterolaemia and the various definitions of sick leave, in both sexes and after adjustment for different covariates. When dividing up aware subjects into treated versus untreated, we observed in men the highest sick leave incidence in aware and treated hypertensive patients as well as in aware and treated hypercholesterolaemic patients. In women findings were less consistent, probably due to the smaller sample size. When looking at cumulative effects by examining participants with both hypertension and hypercholesterolaemia and their level of awareness for one or both risk factors, a statistically significant gradient was noticed in men, with the highest sick leave incidence, whatever the definition, in men aware for both risk factors, followed by men aware for one. In women the same trends were observed, but no level of statistical significance was reached. CONCLUSION: Without being able to test the effect of 'labelling' as such, our study provides support for the association between awareness of two different coronary risk factors and incidence of sick leave. Probably a common mechanism is at the base of these findings. Further research is needed, in order to reduce potential negative effects of screening on human wellbeing as well as on productivity.

Use of benzodiazepine drugs and perceived job stress in a cohort of working men and women in Belgium. Results from the BELSTRESS-study.

The aim of the Belstress Study was to see whether use of benzodiazepines is associated with perceived job stress as measured by Karasek's job-strain model. This model has as its central tenet that the most adverse health outcomes are to be expected in high strain jobs characterized by high job demands and low job control. An extension of the model states that the most noxious combination is high job demands, low control and low social support at work. Sample subjects were recruited from 25 Belgian companies between 1994 and 1998, and cover a wide range of occupations. A 5.6% of 16,094 men and 9.3% of 5012 women aged 35-59 years report use of benzodiazepines during the last month. A clear association is displayed between self-reported use of benzodiazepines and a high strain job compared to a low strain job (men: OR=1.93, 99% CI=1.4-2.6; women: OR=1.66, 99% CI=1.0-2.7), after adjustment is made for socio-demographic confounders (age, level of education, occupational group, employment sector, living situation). The independent association with quartile level of job demands is a striking feature (men: OR of highest quartile compared to lowest quartile group=1.91, 99% CI=1.4-2.6; women: OR=1.99, 99% CI=1.3-3.1). In men, an inverse association with quartile level of job control is observed (OR= 0.65, 99% CI=0.5-0.9) whereas in women a clear tendency in that direction is displayed (OR=0.62, 99% CI=0.4-1.1). The association with low social support is less clear; an independent association between use of benzodiazepines and iso-strain was observed particularly in men.

Relationship of perceived job stress to total coronary risk in a cohort of working men and women in Belgium.

OBJECTIVE: To examine the relationships of job strain and iso-strain psychosocial work environment exposures to 'total coronary risk' (TCR) in a cohort of male and female workers in Belgium. METHODS: The sample consists of 15,079 men and 4639 women aged 35-59 years employed in a wide range of occupations and free of any self-reported personal history of CHD. Karasek's job strain model was used to define high strain (high demands and low control), low strain, active and passive jobs. Iso-strain was defined as the combination of a high strain job with low worksite social support, and is compared to the other combinations. Total coronary risk is a composite measure based on a Framingham function assessing the risk of developing coronary heart disease (CHD) within the next 10 years; high and low levels of TCR were defined. Logistic regressions in each gender were applied to explore relationships, adjusting for age, level of education, occupational class and sector of employment. RESULTS: In male workers, the age-adjusted prevalence of high TCR is highest in (1) in the lowest quartile group of job control and (2) in the 'high strain' group. The multivariate logistic regressions comparing high strain, active and passive work exposures to low strain work did not indicate a significant association with high TCR. Likewise, iso-strain jobs were neither found to be associated with high TCR. CONCLUSION: Our cross-sectional analysis provides no support for the hypothesis that the psychosocial work environment is strongly associated with the TCR estimate in healthy workers.