A growing body of literature has documented that job stress is associated with the development of work-related musculoskeletal disorders (WMSDs). However, the association of WMSDs with job stress has not yet been fully studied in Korean male firefighters. The purpose of this study was to determine the status of WMSDs in almost all Korean male firefighters and to clarify the effect of job stress on the occurrence of WMSDs. The study design was cross-sectional, and 21,466 firefighters were recruited. The study design included a structured questionnaire to assess general characteristics, the Korean Occupational Stress Scale (optional KOSS-26), Center for Epidemiologic Studies-Depression Scale (CES-D), and WMSDs. The chi-square test, and univariate and multivariate logistic regression analyses were used to look for a correlation between general characteristics and job stress, and the occurrence of WMSD. Back pain is the most common WMSD. Among the job stress subgroup, physical environment, job demands, organizational system, occupational climate, lack of reward and job insecurity were related to the occurrence of WMSDs. However, insufficient job control and interpersonal conflict were not related to the occurrence of WMSDs. Job stress was related to the occurrence of WMSDs in Korean male firefighters. To reduce the occurrence of WMSDs, a job stress management program may be required.

Ryoo JH, et al. J Korean Med Sci. 2013 Jun;28(6):855-860. http://dx.doi.org/10.3346/jkms.2013.28.6.855

Resilient individuals have a comprehensive ability to adapt to various life circumstances. Psychological resilience predicts an individual’s physiological response to stress. The 10-item Connor-Davidson Resilience Scale (CD-RISC) is a widely used measure to quantify the level of self-perceived resilience. This study examined the psychometric properties of a Korean version of the 10-item Connor-Davidson Resilience Scale (10-item K-CD-RISC) on workers in Gumi, South Korea, exposed to hydrofluoric acid (HF). The questionnaires included the 10-item K-CD-RISC and Beck Anxiety Inventor (BAI), the Impact of Event Scale-Revised-Korean version (IES-R-K), the Rosen-berg Self Esteem Scale (RSES), the Center for Epidemiologic Studies-Depression Scale (CES-D), and the Perceived Stress Scale (PSS). These were randomly distributed at 237 workplaces near the HF-spill site, in the Gumi 4 complex. The responses of 991 (67.3%) workers were analyzed. The exploratory factor analysis shown that a single-factor model was consistent with the original design of the 10-item CD-RISC. The scale also demonstrated good internal consistency (Cronbach’s alpha = 0.95). Scores on the scale reflected different levels of resilience with respect to personal factors (age, gender, marital status, and education and income levels) that are thought to be differentiated. Differences of resilience were also reflected by psychiatric symptoms (anxiety and depression). Moreover, the total score of scale positively correlated with RSES, whereas the IES-R-K, BAI, CES-D, and the PSS negatively correlated with the 10-item K-CD-RISC. The 10-item K-CD-RISC has good psychometric properties and is applicable for victims exposed to noxious chemical such as HF.

Objectives Historically, little was known about the effects of low blood lead level (BLL < 10 μg/dL) on hypertension (HTN). The purpose of this study was to assess the effects of low BLL on blood pressure (BP) and HTN in lead‐exposed male workers in the Republic of Korea. Methods From the year 2000 to 2004, 12,060 male workers underwent an Annual Specialised Medical Check‐up for lead; 7,341 subjects had a peak BLL < 10 μg/dL and were selected for the study. The quartiles of peak BLL in lead‐exposed workers were as follows: first (0.01‐3.68 μg/dL), second (3.69‐5.19 μg/dL), third (5.20‐6.86 μg/dL), and fourth (6.87‐10.00 μg/dL). To examine the relationship between BLL and pre‐HTN (systolic BP [SBP] ≥120‐140 mmHg; diastolic BP [DBP] ≥80‐90 mmHg) and between BLL and HTN (SBP ≥ 140 mmHg; DBP ≥ 90 mmHg), the quartiles of BLL were used as independent variables in multiple logistic regression analysis. Results In multiple linear regression analyses, SBP (β 0.04, P < .01) and DBP (β 0.06, P < .01) increased in line with a 1 μg/dL increase in BLL. The odds ratio (OR) of HTN in the fourth versus first BLL quartile (1.54; 95% confidence interval [CI]: 1.26, 1.89) was statistically significant. Conclusion SBP and DBP were statistically significantly associated with peak BLL. A BLL ≥ 6.87 μg/dL was associated with HTN; thus, even in workers with low BLLs (<10 μg/dL), management of BP is likely to be necessary. Modulation of the current safety standards for BLLs in workers will be needed.

The main objective of this study was to assess the prevalence of lower back pain (LBP) and clarify the effect of work-related psychological factors on LBP. Nationwide survey data collected from male Korean firefighters (FIFS) were used. To identify the risk factors (work-related psychological factors such as job stress and depression) affecting LBP, the χ² test and multivariate logistic regression analyses were conducted. The prevalence of LBP was 19.3% and was highest in the emergency medical service (31.8%) part of FF job types. Within job stress, an uncomfortable physical environment, high mental job demand and organizational injustice were associated with LBP. However, inadequate social support inversely associated with LBP. Depression and high-risk alcohol drinking were related to LBP. LBP was closely related to job stress, depression and alcohol intake. Proper interventions of psychological factors should therefore be addressed to control LBP in FIFS.