The objective of this 2nd phase of a 2-year study among female nurses was to provide further empirical validation of the demands-control and social support model. The association of job strain with psychological problems and the potential modifying role of social support at work were examined. A questionnaire was sent at the workplace to 1,741 nurses. The same associations were found between psychological demands, decision latitude, and a combination of the 2 with psychological distress and emotional exhaustion for current exposure and for cumulative exposure. Social support had a direct effect on these psychological symptoms but did not modify their association with job strain. Longitudinal and prospective data are needed to study the occurrence and persistence of health problems when exposure is maintained or retrieved.

Background Using Karasek's job strain model, the objective of the study was to determine whether nurses exposed to job strain had a higher incidence of sick leave than nurses not exposed. Methods The design was longitudinal. Data on sick leave were collected for 1,793 nurses for a 20‐month period: short‐term leaves and certified sick leaves. The Job Content Questionnaire was used to measure psychological demands, job decision latitude, and social support at work. Results Short‐term sick leaves were associated with job strain (incidence density ratio (IDR) = 1.20) and with low social support at work (IDR = 1.26). Certified sick leaves were also significantly associated with low social support at work (IDR = 1.27 for all diagnoses and IDR = 1.78 for mental health diagnoses). Conclusions Our results support the association between job strain and short‐term sick leaves. The association with certified sick leaves is also significant for subgroups of nurses with specific job characteristics. Social support at work, although associated with all types of sick leaves measured, does not modify the association between job strain and absence. Am. J. Ind. Med. 39:194–202, 2001. © 2001 Wiley‐Liss, Inc.

T HAS BEEN SHOWN IN SEVERAL 1-6 BUT not all studies 7-9 that job strain, a combination of high psychological demands and low decision latitude, 10 increases the risk of a first coronary heart disease (CHD) event. However, the association of job strain with the risk of recurrent CHD events after a first myocardial infarction (MI) has been documented in only 2 prospective studies whose findings were inconsistent. 11,12 Two major limitations of these previous studies were that they did not assess the duration of psychosocial work exposure 11-13 and were conducted with a limited number of participants (n=62, 11 n=200 12). Our study was undertaken to determine whether job strain increases the risk of recurrent CHD events when the duration of psychosocial work exposure is taken into account in a large cohort who returned to work after a first recent MI. METHODS Patients and Data Collection A total of 1191 patients younger than 60 years were recruited from 30 hospitals in the province of Quebec, Canada, between November 1995 and October 1997. Eligible patients had a first acute MI, held a paid job in the 12 months before their MI, and planned to return to work at least 10 hours per week within 18 months after their MI. The ethics board of each hospital approved the study. Written informed consent was obtained before hospital discharge. The final study population included 972 patients (FIGURE 1). Medical information regarding the acute MI and past medical history was documented during the first hospitalization. Participants were interviewed 3 times by telephone: at baseline in 1996-1998, an average of 6 weeks after their return to work, 2.2 years later in 1998-2000, and after 6.9 years in 2003-2005. Validated questionnaires for the first 2 inter-See also p 1693 and Patient Page.

Objectives: To assess the effectiveness of a workplace intervention aimed at reducing adverse psychosocial work factors (psychological demands, decision latitude, social support, and effort-reward imbalance) and mental health problems among care providers. Methods: A quasi-experimental design with a control group was used. Pre-intervention (71% response rate), and one-year post-intervention measures (69% response rate) were collected by telephone interviews. Results: One year after the intervention, there was a reduction of several adverse psychosocial factors in the experimental group, whereas no such reduction was found in the control group. However, there was a significant deterioration of decision latitude and social support from supervisors in both experimental and control groups. There was also a significant reduction in sleeping problems and work related burnout in the experimental hospital, whereas only sleeping problems decreased in the control group while both client related and personal burnout increased in this hospital. The comparison between the experimental and control groups, after adjusting for pre-intervention measures, showed a significant difference in the means of all psychosocial factors except decision latitude. All other factors were better in the experimental group. Conclusion: Results suggest positive effects of the intervention, even though only 12 months have passed since the beginning of the intervention. Follow up at 36 months is necessary to evaluate whether observed effects are maintained over time. In light of these results, we believe that continuing the participative process in the experimental hospital will foster the achievement of a more important reduction of adverse psychosocial factors at work. It is expected that the intensity of the intervention will be directly related to its beneficial effects. Long term effects will however depend on the willingness of management and of staff to appropriate the process of identifying what contributes to adverse psychosocial factors at work and to adopt means to reduce them.

These results support the long-term effectiveness of the intervention. The reduction in many psychosocial factors in the experimental hospital may have clinical significance since most health indicators also improved in this hospital. These results support the whole process of the intervention given that significant improvements in psychosocial factors and health problems were observed in the experimental hospital but not in the control hospital.